[PATCH v6 0/10] Exynos5 Dynamic Memory Controller driver

[PATCH v6 0/10] Exynos5 Dynamic Memory Controller driver

[Lukasz Luba]

Hi all,

This is v6 of the patch set which adds support of Dynamic Memory Controller
for Exynos5422 SoC.
The driver supports Dynamic Voltage and Frequency Scalling
for the DMC and DRAM. It also provides needed timings for different
speed operations of the DRAM memory.

The patch set depends on changes to Exynos PPMU posted on LKLM as:
[PATCH v3 0/4] Exynos Performance Monitoring Counters enhancements

changes:
v6:
- driver code has been converted to use generic code which parses DT memory
  definition in drivers/memory/of_memory.c
- extended of_memory by LPDDR3 support (there was LPDDR2 made by TI)
- extended jedec_lpddr.h by the needed structures for LPDDR3 (AC timings)
- driver file moved to proper directory, where other memory controllers
  live, which is in this case drivers/memory/samsung/
- driver code now uses regmap_{read|write} to access registers for pausing
  and changing timings set, as suggested by Chanwoo
- DT contains simple definition of memory device, similar to LPDDR2 made by TI
- driver code generates the needed timings for registered OPPs, based on
  memory description in DT
- patch 1 contains Rob's ACK,
- simplified memory bandwidth calculation
- added debug information files with timings, raw counters and statistics
- updated dt-bindings files accordingly
- based on v5.1-rc5 (+ PPMU patches)
v5:
- removed unneeded wrapper functions i.e. for regulator_set_voltage
- removed unused defines
- removed direct access to clock register base and used CCF for
  pause and timing set usage
- switched to OPP comming from DT according to Chanowoo's comments
- switched to timings comming from DT, added parsing function
- extended dt-binding with description of OPPs and timings
- according to Rob Herring comment, moved dt-binding file before driver code
  in the patch set.
- rebased on top of v5.0
v4:
- removed unneeded DPLL and G3D clocks IDs
- changed names of parent clocks for mout_mx_mspll_ccore_phy_p
  and added one more parent: mout_sclk_epll
- removed 933Mhz and 138MHz from the BPLL ratio table
v3:
- in DTS align to proper indent the clocks and clock-names entries
v2:
- changed file name exynos5-dmc.c -> exynos5422-dmc.c
  and related entries in other files
- changed dt-binding file name
- changed config entry to CONFIG_ARM_EXYNOS5422_DMC_DEVFREQ
- removed sysfs and print info messages (print only one line)
- removed function exynos5_read_chip_info and compact code
- changed dt-binding patch and move it up in the patch set
- new entries in MAINTAINERS are added with the driver c code
- clean-up in DTS file: renamed nodes to 'ppmu' and 'memory-controller',
  entries moved to suggested location (before nocp nodes or after),
  moved according to alfabetical order, compacted clocks names with right indent.

Regards,
Lukasz Luba

Lukasz Luba (10):
  clk: samsung: add needed IDs for DMC clocks in Exynos5420
  clk: samsung: add new clocks for DMC for Exynos5422 SoC
  clk: samsung: add BPLL rate table for Exynos 5422 SoC
  Documentation: dt: device tree bindings for LPDDR3 memories
  drivers: memory: extend of_memory by LPDDR3 support
  dt-bindings: memory-controllers: add Exynos5422 DMC device description
  drivers: memory: add DMC driver for Exynos5422
  drivers: devfreq: events: add Exynos PPMU new events
  ARM: dts: exynos: add DMC device for exynos5422
  ARM: exynos_defconfig: enable DMC driver

 .../devicetree/bindings/lpddr3/lpddr3-timings.txt  |   57 +
 .../devicetree/bindings/lpddr3/lpddr3.txt          |   93 +
 .../bindings/memory-controllers/exynos5422-dmc.txt |   73 +
 MAINTAINERS                                        |    8 +
 arch/arm/boot/dts/exynos5420.dtsi                  |  120 ++
 arch/arm/boot/dts/exynos5422-odroid-core.dtsi      |  120 ++
 arch/arm/configs/exynos_defconfig                  |    1 +
 drivers/clk/samsung/clk-exynos5420.c               |   59 +-
 drivers/devfreq/event/exynos-ppmu.c                |    6 +
 drivers/memory/of_memory.c                         |  125 ++
 drivers/memory/of_memory.h                         |   20 +-
 drivers/memory/samsung/Kconfig                     |   17 +
 drivers/memory/samsung/Makefile                    |    1 +
 drivers/memory/samsung/exynos5422-dmc.c            | 1793 ++++++++++++++++++++
 include/dt-bindings/clock/exynos5420.h             |   18 +-
 include/memory/jedec_ddr.h                         |   62 +
 16 files changed, 2566 insertions(+), 7 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
 create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3.txt
 create mode 100644 Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
 create mode 100644 drivers/memory/samsung/exynos5422-dmc.c

-- 
2.7.4

[PATCH v6 01/10] clk: samsung: add needed IDs for DMC clocks in Exynos5420

[Lukasz Luba]

Define new IDs for clocks used by Dynamic Memory Controller in
Exynos5422 SoC.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 include/dt-bindings/clock/exynos5420.h | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/include/dt-bindings/clock/exynos5420.h b/include/dt-bindings/clock/exynos5420.h
index 355f469..abb1842 100644
--- a/include/dt-bindings/clock/exynos5420.h
+++ b/include/dt-bindings/clock/exynos5420.h
@@ -60,6 +60,7 @@
 #define CLK_MAU_EPLL		159
 #define CLK_SCLK_HSIC_12M	160
 #define CLK_SCLK_MPHY_IXTAL24	161
+#define CLK_SCLK_BPLL		162
 
 /* gate clocks */
 #define CLK_UART0		257
@@ -195,6 +196,18 @@
 #define CLK_ACLK432_CAM		518
 #define CLK_ACLK_FL1550_CAM	519
 #define CLK_ACLK550_CAM		520
+#define CLK_CLKM_PHY0		521
+#define CLK_CLKM_PHY1		522
+#define CLK_ACLK_PPMU_DREX0_0	523
+#define CLK_ACLK_PPMU_DREX0_1	524
+#define CLK_ACLK_PPMU_DREX1_0	525
+#define CLK_ACLK_PPMU_DREX1_1	526
+#define CLK_PCLK_PPMU_DREX0_0	527
+#define CLK_PCLK_PPMU_DREX0_1	528
+#define CLK_PCLK_PPMU_DREX1_0	529
+#define CLK_PCLK_PPMU_DREX1_1	530
+#define CLK_CDREX_PAUSE		531
+#define CLK_CDREX_TIMING_SET	532
 
 /* mux clocks */
 #define CLK_MOUT_HDMI		640
@@ -217,6 +230,8 @@
 #define CLK_MOUT_EPLL		657
 #define CLK_MOUT_MAU_EPLL	658
 #define CLK_MOUT_USER_MAU_EPLL	659
+#define CLK_MOUT_SCLK_SPLL	660
+#define CLK_MOUT_MX_MSPLL_CCORE_PHY	661
 
 /* divider clocks */
 #define CLK_DOUT_PIXEL		768
@@ -248,8 +263,9 @@
 #define CLK_DOUT_CCLK_DREX0	794
 #define CLK_DOUT_CLK2X_PHY0	795
 #define CLK_DOUT_PCLK_CORE_MEM	796
+#define CLK_FF_DOUT_SPLL2	797
 
 /* must be greater than maximal clock id */
-#define CLK_NR_CLKS		797
+#define CLK_NR_CLKS		798
 
 #endif /* _DT_BINDINGS_CLOCK_EXYNOS_5420_H */
-- 
2.7.4

Re: [PATCH v6 01/10] clk: samsung: add needed IDs for DMC clocks in Exynos5420

[Chanwoo Choi]

Hi,

On 19. 4. 19. 오후 11:19, Lukasz Luba wrote:
> Define new IDs for clocks used by Dynamic Memory Controller in
> Exynos5422 SoC.
> 
> Acked-by: Rob Herring <robh@kernel.org>
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  include/dt-bindings/clock/exynos5420.h | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
> 
> diff --git a/include/dt-bindings/clock/exynos5420.h b/include/dt-bindings/clock/exynos5420.h
> index 355f469..abb1842 100644
> --- a/include/dt-bindings/clock/exynos5420.h
> +++ b/include/dt-bindings/clock/exynos5420.h
> @@ -60,6 +60,7 @@
>  #define CLK_MAU_EPLL		159
>  #define CLK_SCLK_HSIC_12M	160
>  #define CLK_SCLK_MPHY_IXTAL24	161
> +#define CLK_SCLK_BPLL		162
>  
>  /* gate clocks */
>  #define CLK_UART0		257
> @@ -195,6 +196,18 @@
>  #define CLK_ACLK432_CAM		518
>  #define CLK_ACLK_FL1550_CAM	519
>  #define CLK_ACLK550_CAM		520
> +#define CLK_CLKM_PHY0		521
> +#define CLK_CLKM_PHY1		522
> +#define CLK_ACLK_PPMU_DREX0_0	523
> +#define CLK_ACLK_PPMU_DREX0_1	524
> +#define CLK_ACLK_PPMU_DREX1_0	525
> +#define CLK_ACLK_PPMU_DREX1_1	526
> +#define CLK_PCLK_PPMU_DREX0_0	527
> +#define CLK_PCLK_PPMU_DREX0_1	528
> +#define CLK_PCLK_PPMU_DREX1_0	529
> +#define CLK_PCLK_PPMU_DREX1_1	530
> +#define CLK_CDREX_PAUSE		531
> +#define CLK_CDREX_TIMING_SET	532

I cannot find the usage code of both CLK_CDREX_PAUSE
and CLK_CDREX_TIMING_SET in these patchset. 

Please remove them.

(snip)

-- 
Best Regards,
Chanwoo Choi
Samsung Electronics

Re: [PATCH v6 01/10] clk: samsung: add needed IDs for DMC clocks in Exynos5420

[Lukasz Luba]

Hi Chanwoo,

On 4/30/19 6:47 AM, Chanwoo Choi wrote:
> Hi,
> 
> On 19. 4. 19. 오후 11:19, Lukasz Luba wrote:
>> Define new IDs for clocks used by Dynamic Memory Controller in
>> Exynos5422 SoC.
>>
>> Acked-by: Rob Herring <robh@kernel.org>
>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>> ---
>>   include/dt-bindings/clock/exynos5420.h | 18 +++++++++++++++++-
>>   1 file changed, 17 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/dt-bindings/clock/exynos5420.h b/include/dt-bindings/clock/exynos5420.h
>> index 355f469..abb1842 100644
>> --- a/include/dt-bindings/clock/exynos5420.h
>> +++ b/include/dt-bindings/clock/exynos5420.h
>> @@ -60,6 +60,7 @@
>>   #define CLK_MAU_EPLL		159
>>   #define CLK_SCLK_HSIC_12M	160
>>   #define CLK_SCLK_MPHY_IXTAL24	161
>> +#define CLK_SCLK_BPLL		162
>>   
>>   /* gate clocks */
>>   #define CLK_UART0		257
>> @@ -195,6 +196,18 @@
>>   #define CLK_ACLK432_CAM		518
>>   #define CLK_ACLK_FL1550_CAM	519
>>   #define CLK_ACLK550_CAM		520
>> +#define CLK_CLKM_PHY0		521
>> +#define CLK_CLKM_PHY1		522
>> +#define CLK_ACLK_PPMU_DREX0_0	523
>> +#define CLK_ACLK_PPMU_DREX0_1	524
>> +#define CLK_ACLK_PPMU_DREX1_0	525
>> +#define CLK_ACLK_PPMU_DREX1_1	526
>> +#define CLK_PCLK_PPMU_DREX0_0	527
>> +#define CLK_PCLK_PPMU_DREX0_1	528
>> +#define CLK_PCLK_PPMU_DREX1_0	529
>> +#define CLK_PCLK_PPMU_DREX1_1	530
>> +#define CLK_CDREX_PAUSE		531
>> +#define CLK_CDREX_TIMING_SET	532
> 
> I cannot find the usage code of both CLK_CDREX_PAUSE
> and CLK_CDREX_TIMING_SET in these patchset.
Thank you for this catch. I will remove them.

Regards,
Lukasz
> 
> Please remove them.
> 
> (snip)
> 

[PATCH v6 02/10] clk: samsung: add new clocks for DMC for Exynos5422 SoC

[Lukasz Luba]

This patch provides support for clocks needed for Dynamic Memory Controller
in Exynos5422 SoC. It adds CDREX base register addresses, new DIV, MUX and
GATE entries.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 drivers/clk/samsung/clk-exynos5420.c | 46 ++++++++++++++++++++++++++++++++----
 1 file changed, 42 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
index 34cce3c..d9e6653 100644
--- a/drivers/clk/samsung/clk-exynos5420.c
+++ b/drivers/clk/samsung/clk-exynos5420.c
@@ -134,6 +134,8 @@
 #define SRC_CDREX		0x20200
 #define DIV_CDREX0		0x20500
 #define DIV_CDREX1		0x20504
+#define GATE_BUS_CDREX0		0x20700
+#define GATE_BUS_CDREX1		0x20704
 #define KPLL_LOCK		0x28000
 #define KPLL_CON0		0x28100
 #define SRC_KFC			0x28200
@@ -248,6 +250,8 @@ static const unsigned long exynos5x_clk_regs[] __initconst = {
 	DIV_CDREX1,
 	SRC_KFC,
 	DIV_KFC0,
+	GATE_BUS_CDREX0,
+	GATE_BUS_CDREX1,
 };
 
 static const unsigned long exynos5800_clk_regs[] __initconst = {
@@ -425,6 +429,9 @@ PNAME(mout_group13_5800_p)	= { "dout_osc_div", "mout_sw_aclkfl1_550_cam" };
 PNAME(mout_group14_5800_p)	= { "dout_aclk550_cam", "dout_sclk_sw" };
 PNAME(mout_group15_5800_p)	= { "dout_osc_div", "mout_sw_aclk550_cam" };
 PNAME(mout_group16_5800_p)	= { "dout_osc_div", "mout_mau_epll_clk" };
+PNAME(mout_mx_mspll_ccore_phy_p) = { "sclk_bpll", "mout_sclk_dpll",
+					"mout_sclk_mpll", "ff_dout_spll2",
+					"mout_sclk_spll", "mout_sclk_epll"};
 
 /* fixed rate clocks generated outside the soc */
 static struct samsung_fixed_rate_clock
@@ -450,7 +457,7 @@ static const struct samsung_fixed_factor_clock
 static const struct samsung_fixed_factor_clock
 		exynos5800_fixed_factor_clks[] __initconst = {
 	FFACTOR(0, "ff_dout_epll2", "mout_sclk_epll", 1, 2, 0),
-	FFACTOR(0, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
+	FFACTOR(CLK_FF_DOUT_SPLL2, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
 };
 
 static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
@@ -472,11 +479,14 @@ static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
 	MUX(0, "mout_aclk300_disp1", mout_group5_5800_p, SRC_TOP2, 24, 2),
 	MUX(0, "mout_aclk300_gscl", mout_group5_5800_p, SRC_TOP2, 28, 2),
 
+	MUX(CLK_MOUT_MX_MSPLL_CCORE_PHY, "mout_mx_mspll_ccore_phy",
+		mout_mx_mspll_ccore_phy_p, SRC_TOP7, 0, 3),
+
 	MUX(CLK_MOUT_MX_MSPLL_CCORE, "mout_mx_mspll_ccore",
-			mout_mx_mspll_ccore_p, SRC_TOP7, 16, 2),
+			mout_mx_mspll_ccore_p, SRC_TOP7, 16, 3),
 	MUX_F(CLK_MOUT_MAU_EPLL, "mout_mau_epll_clk", mout_mau_epll_clk_5800_p,
 			SRC_TOP7, 20, 2, CLK_SET_RATE_PARENT, 0),
-	MUX(0, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
+	MUX(CLK_SCLK_BPLL, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
 	MUX(0, "mout_epll2", mout_epll2_5800_p, SRC_TOP7, 28, 1),
 
 	MUX(0, "mout_aclk550_cam", mout_group3_5800_p, SRC_TOP8, 16, 3),
@@ -648,7 +658,7 @@ static const struct samsung_mux_clock exynos5x_mux_clks[] __initconst = {
 
 	MUX(0, "mout_sclk_mpll", mout_mpll_p, SRC_TOP6, 0, 1),
 	MUX(CLK_MOUT_VPLL, "mout_sclk_vpll", mout_vpll_p, SRC_TOP6, 4, 1),
-	MUX(0, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
+	MUX(CLK_MOUT_SCLK_SPLL, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
 	MUX(0, "mout_sclk_ipll", mout_ipll_p, SRC_TOP6, 12, 1),
 	MUX(0, "mout_sclk_rpll", mout_rpll_p, SRC_TOP6, 16, 1),
 	MUX_F(CLK_MOUT_EPLL, "mout_sclk_epll", mout_epll_p, SRC_TOP6, 20, 1,
@@ -817,6 +827,8 @@ static const struct samsung_div_clock exynos5x_div_clks[] __initconst = {
 	DIV(CLK_DOUT_CLK2X_PHY0, "dout_clk2x_phy0", "dout_sclk_cdrex",
 			DIV_CDREX0, 3, 5),
 
+	DIV(0, "dout_pclk_drex0", "dout_cclk_drex0", DIV_CDREX0, 28, 3),
+
 	DIV(CLK_DOUT_PCLK_CORE_MEM, "dout_pclk_core_mem", "mout_mclk_cdrex",
 			DIV_CDREX1, 8, 3),
 
@@ -1170,6 +1182,32 @@ static const struct samsung_gate_clock exynos5x_gate_clks[] __initconst = {
 			GATE_TOP_SCLK_ISP, 12, CLK_SET_RATE_PARENT, 0),
 
 	GATE(CLK_G3D, "g3d", "mout_user_aclk_g3d", GATE_IP_G3D, 9, 0, 0),
+
+	/* CDREX */
+	GATE(CLK_CLKM_PHY0, "clkm_phy0", "dout_sclk_cdrex",
+			GATE_BUS_CDREX0, 0, 0, 0),
+	GATE(CLK_CLKM_PHY1, "clkm_phy1", "dout_sclk_cdrex",
+			GATE_BUS_CDREX0, 1, 0, 0),
+	GATE(0, "mx_mspll_ccore_phy", "mout_mx_mspll_ccore_phy",
+			SRC_MASK_TOP7, 0, CLK_IGNORE_UNUSED, 0),
+
+	GATE(CLK_ACLK_PPMU_DREX1_1, "aclk_ppmu_drex1_1", "dout_aclk_cdrex1",
+			GATE_BUS_CDREX1, 12, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_ACLK_PPMU_DREX1_0, "aclk_ppmu_drex1_0", "dout_aclk_cdrex1",
+			GATE_BUS_CDREX1, 13, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_ACLK_PPMU_DREX0_1, "aclk_ppmu_drex0_1", "dout_aclk_cdrex1",
+			GATE_BUS_CDREX1, 14, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_ACLK_PPMU_DREX0_0, "aclk_ppmu_drex0_0", "dout_aclk_cdrex1",
+			GATE_BUS_CDREX1, 15, CLK_IGNORE_UNUSED, 0),
+
+	GATE(CLK_PCLK_PPMU_DREX1_1, "pclk_ppmu_drex1_1", "dout_pclk_cdrex",
+			GATE_BUS_CDREX1, 26, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_PCLK_PPMU_DREX1_0, "pclk_ppmu_drex1_0", "dout_pclk_cdrex",
+			GATE_BUS_CDREX1, 27, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_PCLK_PPMU_DREX0_1, "pclk_ppmu_drex0_1", "dout_pclk_cdrex",
+			GATE_BUS_CDREX1, 28, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_PCLK_PPMU_DREX0_0, "pclk_ppmu_drex0_0", "dout_pclk_cdrex",
+			GATE_BUS_CDREX1, 29, CLK_IGNORE_UNUSED, 0),
 };
 
 static const struct samsung_div_clock exynos5x_disp_div_clks[] __initconst = {
-- 
2.7.4

Re: [PATCH v6 02/10] clk: samsung: add new clocks for DMC for Exynos5422 SoC

[Chanwoo Choi]

Hi Lukasz,

I have no objection about this patch. 
Instead, as I commented on v4, in order to reduce the confusion
about multiple clock definitions with same bit range of DIV_CDREX0,

You need to add the additional comment and you better to
define the three clocks at the nearby in this driver.
(CLKDIV_PCLK_CDREX, CLKDIV_PCLK_DREX0, CLKDIV_PCLK_DREX1)
If they are scattered, it is difficult for understanding
why they are developed like this.

[1] [v4,2/8] clk: samsung: add new clocks for DMC for Exynos5422 SoC
- https://lkml.org/lkml/2019/2/12/12

Regards,
Chanwoo Choi


On 19. 4. 19. 오후 11:19, Lukasz Luba wrote:
> This patch provides support for clocks needed for Dynamic Memory Controller
> in Exynos5422 SoC. It adds CDREX base register addresses, new DIV, MUX and
> GATE entries.
> 
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  drivers/clk/samsung/clk-exynos5420.c | 46 ++++++++++++++++++++++++++++++++----
>  1 file changed, 42 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
> index 34cce3c..d9e6653 100644
> --- a/drivers/clk/samsung/clk-exynos5420.c
> +++ b/drivers/clk/samsung/clk-exynos5420.c
> @@ -134,6 +134,8 @@
>  #define SRC_CDREX		0x20200
>  #define DIV_CDREX0		0x20500
>  #define DIV_CDREX1		0x20504
> +#define GATE_BUS_CDREX0		0x20700
> +#define GATE_BUS_CDREX1		0x20704
>  #define KPLL_LOCK		0x28000
>  #define KPLL_CON0		0x28100
>  #define SRC_KFC			0x28200
> @@ -248,6 +250,8 @@ static const unsigned long exynos5x_clk_regs[] __initconst = {
>  	DIV_CDREX1,
>  	SRC_KFC,
>  	DIV_KFC0,
> +	GATE_BUS_CDREX0,
> +	GATE_BUS_CDREX1,
>  };
>  
>  static const unsigned long exynos5800_clk_regs[] __initconst = {
> @@ -425,6 +429,9 @@ PNAME(mout_group13_5800_p)	= { "dout_osc_div", "mout_sw_aclkfl1_550_cam" };
>  PNAME(mout_group14_5800_p)	= { "dout_aclk550_cam", "dout_sclk_sw" };
>  PNAME(mout_group15_5800_p)	= { "dout_osc_div", "mout_sw_aclk550_cam" };
>  PNAME(mout_group16_5800_p)	= { "dout_osc_div", "mout_mau_epll_clk" };
> +PNAME(mout_mx_mspll_ccore_phy_p) = { "sclk_bpll", "mout_sclk_dpll",
> +					"mout_sclk_mpll", "ff_dout_spll2",
> +					"mout_sclk_spll", "mout_sclk_epll"};
>  
>  /* fixed rate clocks generated outside the soc */
>  static struct samsung_fixed_rate_clock
> @@ -450,7 +457,7 @@ static const struct samsung_fixed_factor_clock
>  static const struct samsung_fixed_factor_clock
>  		exynos5800_fixed_factor_clks[] __initconst = {
>  	FFACTOR(0, "ff_dout_epll2", "mout_sclk_epll", 1, 2, 0),
> -	FFACTOR(0, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
> +	FFACTOR(CLK_FF_DOUT_SPLL2, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
>  };
>  
>  static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
> @@ -472,11 +479,14 @@ static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
>  	MUX(0, "mout_aclk300_disp1", mout_group5_5800_p, SRC_TOP2, 24, 2),
>  	MUX(0, "mout_aclk300_gscl", mout_group5_5800_p, SRC_TOP2, 28, 2),
>  
> +	MUX(CLK_MOUT_MX_MSPLL_CCORE_PHY, "mout_mx_mspll_ccore_phy",
> +		mout_mx_mspll_ccore_phy_p, SRC_TOP7, 0, 3),
> +
>  	MUX(CLK_MOUT_MX_MSPLL_CCORE, "mout_mx_mspll_ccore",
> -			mout_mx_mspll_ccore_p, SRC_TOP7, 16, 2),
> +			mout_mx_mspll_ccore_p, SRC_TOP7, 16, 3),
>  	MUX_F(CLK_MOUT_MAU_EPLL, "mout_mau_epll_clk", mout_mau_epll_clk_5800_p,
>  			SRC_TOP7, 20, 2, CLK_SET_RATE_PARENT, 0),
> -	MUX(0, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
> +	MUX(CLK_SCLK_BPLL, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
>  	MUX(0, "mout_epll2", mout_epll2_5800_p, SRC_TOP7, 28, 1),
>  
>  	MUX(0, "mout_aclk550_cam", mout_group3_5800_p, SRC_TOP8, 16, 3),
> @@ -648,7 +658,7 @@ static const struct samsung_mux_clock exynos5x_mux_clks[] __initconst = {
>  
>  	MUX(0, "mout_sclk_mpll", mout_mpll_p, SRC_TOP6, 0, 1),
>  	MUX(CLK_MOUT_VPLL, "mout_sclk_vpll", mout_vpll_p, SRC_TOP6, 4, 1),
> -	MUX(0, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
> +	MUX(CLK_MOUT_SCLK_SPLL, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
>  	MUX(0, "mout_sclk_ipll", mout_ipll_p, SRC_TOP6, 12, 1),
>  	MUX(0, "mout_sclk_rpll", mout_rpll_p, SRC_TOP6, 16, 1),
>  	MUX_F(CLK_MOUT_EPLL, "mout_sclk_epll", mout_epll_p, SRC_TOP6, 20, 1,
> @@ -817,6 +827,8 @@ static const struct samsung_div_clock exynos5x_div_clks[] __initconst = {
>  	DIV(CLK_DOUT_CLK2X_PHY0, "dout_clk2x_phy0", "dout_sclk_cdrex",
>  			DIV_CDREX0, 3, 5),
>  
> +	DIV(0, "dout_pclk_drex0", "dout_cclk_drex0", DIV_CDREX0, 28, 3),
> +
>  	DIV(CLK_DOUT_PCLK_CORE_MEM, "dout_pclk_core_mem", "mout_mclk_cdrex",
>  			DIV_CDREX1, 8, 3),
>  
> @@ -1170,6 +1182,32 @@ static const struct samsung_gate_clock exynos5x_gate_clks[] __initconst = {
>  			GATE_TOP_SCLK_ISP, 12, CLK_SET_RATE_PARENT, 0),
>  
>  	GATE(CLK_G3D, "g3d", "mout_user_aclk_g3d", GATE_IP_G3D, 9, 0, 0),
> +
> +	/* CDREX */
> +	GATE(CLK_CLKM_PHY0, "clkm_phy0", "dout_sclk_cdrex",
> +			GATE_BUS_CDREX0, 0, 0, 0),
> +	GATE(CLK_CLKM_PHY1, "clkm_phy1", "dout_sclk_cdrex",
> +			GATE_BUS_CDREX0, 1, 0, 0),
> +	GATE(0, "mx_mspll_ccore_phy", "mout_mx_mspll_ccore_phy",
> +			SRC_MASK_TOP7, 0, CLK_IGNORE_UNUSED, 0),
> +
> +	GATE(CLK_ACLK_PPMU_DREX1_1, "aclk_ppmu_drex1_1", "dout_aclk_cdrex1",
> +			GATE_BUS_CDREX1, 12, CLK_IGNORE_UNUSED, 0),
> +	GATE(CLK_ACLK_PPMU_DREX1_0, "aclk_ppmu_drex1_0", "dout_aclk_cdrex1",
> +			GATE_BUS_CDREX1, 13, CLK_IGNORE_UNUSED, 0),
> +	GATE(CLK_ACLK_PPMU_DREX0_1, "aclk_ppmu_drex0_1", "dout_aclk_cdrex1",
> +			GATE_BUS_CDREX1, 14, CLK_IGNORE_UNUSED, 0),
> +	GATE(CLK_ACLK_PPMU_DREX0_0, "aclk_ppmu_drex0_0", "dout_aclk_cdrex1",
> +			GATE_BUS_CDREX1, 15, CLK_IGNORE_UNUSED, 0),
> +
> +	GATE(CLK_PCLK_PPMU_DREX1_1, "pclk_ppmu_drex1_1", "dout_pclk_cdrex",
> +			GATE_BUS_CDREX1, 26, CLK_IGNORE_UNUSED, 0),
> +	GATE(CLK_PCLK_PPMU_DREX1_0, "pclk_ppmu_drex1_0", "dout_pclk_cdrex",
> +			GATE_BUS_CDREX1, 27, CLK_IGNORE_UNUSED, 0),
> +	GATE(CLK_PCLK_PPMU_DREX0_1, "pclk_ppmu_drex0_1", "dout_pclk_cdrex",
> +			GATE_BUS_CDREX1, 28, CLK_IGNORE_UNUSED, 0),
> +	GATE(CLK_PCLK_PPMU_DREX0_0, "pclk_ppmu_drex0_0", "dout_pclk_cdrex",
> +			GATE_BUS_CDREX1, 29, CLK_IGNORE_UNUSED, 0),
>  };
>  
>  static const struct samsung_div_clock exynos5x_disp_div_clks[] __initconst = {
> 


-- 
Best Regards,
Chanwoo Choi
Samsung Electronics

Re: [PATCH v6 02/10] clk: samsung: add new clocks for DMC for Exynos5422 SoC

[Lukasz Luba]

Hi Chanwoo,

On 4/30/19 3:31 AM, Chanwoo Choi wrote:
> Hi Lukasz,
> 
> I have no objection about this patch.
> Instead, as I commented on v4, in order to reduce the confusion
> about multiple clock definitions with same bit range of DIV_CDREX0,
> 
> You need to add the additional comment and you better to
> define the three clocks at the nearby in this driver.
> (CLKDIV_PCLK_CDREX, CLKDIV_PCLK_DREX0, CLKDIV_PCLK_DREX1)
> If they are scattered, it is difficult for understanding
> why they are developed like this.
> 
> [1] [v4,2/8] clk: samsung: add new clocks for DMC for Exynos5422 SoC
> - https://lkml.org/lkml/2019/2/12/12
> 
OK, I will put these three clocks in one place (below 
CLK_DOUT_PCLK_CDREX definition and ad proper comment regarding
this HW assumption. I will also add these two new IDs
  #define CLK_DOUT_PCLK_CDREX    791
+#define CLK_DOUT_PCLK_DREX0    792
+#define CLK_DOUT_PCLK_DREX1    793
To the header file near the CLK_DOUT_PCLK_CDREX declaration.

After that they will be grouped and commented properly.

Thank you for the review.

Regards,
Lukasz

> Regards,
> Chanwoo Choi
> 
> 
> On 19. 4. 19. 오후 11:19, Lukasz Luba wrote:
>> This patch provides support for clocks needed for Dynamic Memory Controller
>> in Exynos5422 SoC. It adds CDREX base register addresses, new DIV, MUX and
>> GATE entries.
>>
>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>> ---
>>   drivers/clk/samsung/clk-exynos5420.c | 46 ++++++++++++++++++++++++++++++++----
>>   1 file changed, 42 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
>> index 34cce3c..d9e6653 100644
>> --- a/drivers/clk/samsung/clk-exynos5420.c
>> +++ b/drivers/clk/samsung/clk-exynos5420.c
>> @@ -134,6 +134,8 @@
>>   #define SRC_CDREX		0x20200
>>   #define DIV_CDREX0		0x20500
>>   #define DIV_CDREX1		0x20504
>> +#define GATE_BUS_CDREX0		0x20700
>> +#define GATE_BUS_CDREX1		0x20704
>>   #define KPLL_LOCK		0x28000
>>   #define KPLL_CON0		0x28100
>>   #define SRC_KFC			0x28200
>> @@ -248,6 +250,8 @@ static const unsigned long exynos5x_clk_regs[] __initconst = {
>>   	DIV_CDREX1,
>>   	SRC_KFC,
>>   	DIV_KFC0,
>> +	GATE_BUS_CDREX0,
>> +	GATE_BUS_CDREX1,
>>   };
>>   
>>   static const unsigned long exynos5800_clk_regs[] __initconst = {
>> @@ -425,6 +429,9 @@ PNAME(mout_group13_5800_p)	= { "dout_osc_div", "mout_sw_aclkfl1_550_cam" };
>>   PNAME(mout_group14_5800_p)	= { "dout_aclk550_cam", "dout_sclk_sw" };
>>   PNAME(mout_group15_5800_p)	= { "dout_osc_div", "mout_sw_aclk550_cam" };
>>   PNAME(mout_group16_5800_p)	= { "dout_osc_div", "mout_mau_epll_clk" };
>> +PNAME(mout_mx_mspll_ccore_phy_p) = { "sclk_bpll", "mout_sclk_dpll",
>> +					"mout_sclk_mpll", "ff_dout_spll2",
>> +					"mout_sclk_spll", "mout_sclk_epll"};
>>   
>>   /* fixed rate clocks generated outside the soc */
>>   static struct samsung_fixed_rate_clock
>> @@ -450,7 +457,7 @@ static const struct samsung_fixed_factor_clock
>>   static const struct samsung_fixed_factor_clock
>>   		exynos5800_fixed_factor_clks[] __initconst = {
>>   	FFACTOR(0, "ff_dout_epll2", "mout_sclk_epll", 1, 2, 0),
>> -	FFACTOR(0, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
>> +	FFACTOR(CLK_FF_DOUT_SPLL2, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
>>   };
>>   
>>   static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
>> @@ -472,11 +479,14 @@ static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
>>   	MUX(0, "mout_aclk300_disp1", mout_group5_5800_p, SRC_TOP2, 24, 2),
>>   	MUX(0, "mout_aclk300_gscl", mout_group5_5800_p, SRC_TOP2, 28, 2),
>>   
>> +	MUX(CLK_MOUT_MX_MSPLL_CCORE_PHY, "mout_mx_mspll_ccore_phy",
>> +		mout_mx_mspll_ccore_phy_p, SRC_TOP7, 0, 3),
>> +
>>   	MUX(CLK_MOUT_MX_MSPLL_CCORE, "mout_mx_mspll_ccore",
>> -			mout_mx_mspll_ccore_p, SRC_TOP7, 16, 2),
>> +			mout_mx_mspll_ccore_p, SRC_TOP7, 16, 3),
>>   	MUX_F(CLK_MOUT_MAU_EPLL, "mout_mau_epll_clk", mout_mau_epll_clk_5800_p,
>>   			SRC_TOP7, 20, 2, CLK_SET_RATE_PARENT, 0),
>> -	MUX(0, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
>> +	MUX(CLK_SCLK_BPLL, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
>>   	MUX(0, "mout_epll2", mout_epll2_5800_p, SRC_TOP7, 28, 1),
>>   
>>   	MUX(0, "mout_aclk550_cam", mout_group3_5800_p, SRC_TOP8, 16, 3),
>> @@ -648,7 +658,7 @@ static const struct samsung_mux_clock exynos5x_mux_clks[] __initconst = {
>>   
>>   	MUX(0, "mout_sclk_mpll", mout_mpll_p, SRC_TOP6, 0, 1),
>>   	MUX(CLK_MOUT_VPLL, "mout_sclk_vpll", mout_vpll_p, SRC_TOP6, 4, 1),
>> -	MUX(0, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
>> +	MUX(CLK_MOUT_SCLK_SPLL, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
>>   	MUX(0, "mout_sclk_ipll", mout_ipll_p, SRC_TOP6, 12, 1),
>>   	MUX(0, "mout_sclk_rpll", mout_rpll_p, SRC_TOP6, 16, 1),
>>   	MUX_F(CLK_MOUT_EPLL, "mout_sclk_epll", mout_epll_p, SRC_TOP6, 20, 1,
>> @@ -817,6 +827,8 @@ static const struct samsung_div_clock exynos5x_div_clks[] __initconst = {
>>   	DIV(CLK_DOUT_CLK2X_PHY0, "dout_clk2x_phy0", "dout_sclk_cdrex",
>>   			DIV_CDREX0, 3, 5),
>>   
>> +	DIV(0, "dout_pclk_drex0", "dout_cclk_drex0", DIV_CDREX0, 28, 3),
>> +
>>   	DIV(CLK_DOUT_PCLK_CORE_MEM, "dout_pclk_core_mem", "mout_mclk_cdrex",
>>   			DIV_CDREX1, 8, 3),
>>   
>> @@ -1170,6 +1182,32 @@ static const struct samsung_gate_clock exynos5x_gate_clks[] __initconst = {
>>   			GATE_TOP_SCLK_ISP, 12, CLK_SET_RATE_PARENT, 0),
>>   
>>   	GATE(CLK_G3D, "g3d", "mout_user_aclk_g3d", GATE_IP_G3D, 9, 0, 0),
>> +
>> +	/* CDREX */
>> +	GATE(CLK_CLKM_PHY0, "clkm_phy0", "dout_sclk_cdrex",
>> +			GATE_BUS_CDREX0, 0, 0, 0),
>> +	GATE(CLK_CLKM_PHY1, "clkm_phy1", "dout_sclk_cdrex",
>> +			GATE_BUS_CDREX0, 1, 0, 0),
>> +	GATE(0, "mx_mspll_ccore_phy", "mout_mx_mspll_ccore_phy",
>> +			SRC_MASK_TOP7, 0, CLK_IGNORE_UNUSED, 0),
>> +
>> +	GATE(CLK_ACLK_PPMU_DREX1_1, "aclk_ppmu_drex1_1", "dout_aclk_cdrex1",
>> +			GATE_BUS_CDREX1, 12, CLK_IGNORE_UNUSED, 0),
>> +	GATE(CLK_ACLK_PPMU_DREX1_0, "aclk_ppmu_drex1_0", "dout_aclk_cdrex1",
>> +			GATE_BUS_CDREX1, 13, CLK_IGNORE_UNUSED, 0),
>> +	GATE(CLK_ACLK_PPMU_DREX0_1, "aclk_ppmu_drex0_1", "dout_aclk_cdrex1",
>> +			GATE_BUS_CDREX1, 14, CLK_IGNORE_UNUSED, 0),
>> +	GATE(CLK_ACLK_PPMU_DREX0_0, "aclk_ppmu_drex0_0", "dout_aclk_cdrex1",
>> +			GATE_BUS_CDREX1, 15, CLK_IGNORE_UNUSED, 0),
>> +
>> +	GATE(CLK_PCLK_PPMU_DREX1_1, "pclk_ppmu_drex1_1", "dout_pclk_cdrex",
>> +			GATE_BUS_CDREX1, 26, CLK_IGNORE_UNUSED, 0),
>> +	GATE(CLK_PCLK_PPMU_DREX1_0, "pclk_ppmu_drex1_0", "dout_pclk_cdrex",
>> +			GATE_BUS_CDREX1, 27, CLK_IGNORE_UNUSED, 0),
>> +	GATE(CLK_PCLK_PPMU_DREX0_1, "pclk_ppmu_drex0_1", "dout_pclk_cdrex",
>> +			GATE_BUS_CDREX1, 28, CLK_IGNORE_UNUSED, 0),
>> +	GATE(CLK_PCLK_PPMU_DREX0_0, "pclk_ppmu_drex0_0", "dout_pclk_cdrex",
>> +			GATE_BUS_CDREX1, 29, CLK_IGNORE_UNUSED, 0),
>>   };
>>   
>>   static const struct samsung_div_clock exynos5x_disp_div_clks[] __initconst = {
>>
> 
> 

[PATCH v6 03/10] clk: samsung: add BPLL rate table for Exynos 5422 SoC

[Lukasz Luba]

Add new table rate for BPLL for Exynos5422 SoC supporting Dynamic Memory
Controller frequencies for driver's DRAM timings.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 drivers/clk/samsung/clk-exynos5420.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
index d9e6653..ddee8bd 100644
--- a/drivers/clk/samsung/clk-exynos5420.c
+++ b/drivers/clk/samsung/clk-exynos5420.c
@@ -1323,6 +1323,17 @@ static const struct samsung_pll_rate_table exynos5420_pll2550x_24mhz_tbl[] __ini
 	PLL_35XX_RATE(24 * MHZ, 200000000,  200, 3, 3),
 };
 
+static const struct samsung_pll_rate_table exynos5422_bpll_rate_table[] = {
+	PLL_35XX_RATE(24 * MHZ, 825000000, 275, 4, 1),
+	PLL_35XX_RATE(24 * MHZ, 728000000, 182, 3, 1),
+	PLL_35XX_RATE(24 * MHZ, 633000000, 211, 4, 1),
+	PLL_35XX_RATE(24 * MHZ, 543000000, 181, 2, 2),
+	PLL_35XX_RATE(24 * MHZ, 413000000, 413, 6, 2),
+	PLL_35XX_RATE(24 * MHZ, 275000000, 275, 3, 3),
+	PLL_35XX_RATE(24 * MHZ, 206000000, 206, 3, 3),
+	PLL_35XX_RATE(24 * MHZ, 165000000, 110, 2, 3),
+};
+
 static const struct samsung_pll_rate_table exynos5420_epll_24mhz_tbl[] = {
 	PLL_36XX_RATE(24 * MHZ, 600000000U, 100, 2, 1, 0),
 	PLL_36XX_RATE(24 * MHZ, 400000000U, 200, 3, 2, 0),
@@ -1465,7 +1476,7 @@ static void __init exynos5x_clk_init(struct device_node *np,
 		exynos5x_plls[apll].rate_table = exynos5420_pll2550x_24mhz_tbl;
 		exynos5x_plls[epll].rate_table = exynos5420_epll_24mhz_tbl;
 		exynos5x_plls[kpll].rate_table = exynos5420_pll2550x_24mhz_tbl;
-		exynos5x_plls[bpll].rate_table = exynos5420_pll2550x_24mhz_tbl;
+		exynos5x_plls[bpll].rate_table = exynos5422_bpll_rate_table;
 	}
 
 	samsung_clk_register_pll(ctx, exynos5x_plls, ARRAY_SIZE(exynos5x_plls),
-- 
2.7.4

Re: [PATCH v6 03/10] clk: samsung: add BPLL rate table for Exynos 5422 SoC

[Chanwoo Choi]

Hi Lukasz,

On 19. 4. 19. 오후 11:19, Lukasz Luba wrote:
> Add new table rate for BPLL for Exynos5422 SoC supporting Dynamic Memory
> Controller frequencies for driver's DRAM timings.
> 
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  drivers/clk/samsung/clk-exynos5420.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
> index d9e6653..ddee8bd 100644
> --- a/drivers/clk/samsung/clk-exynos5420.c
> +++ b/drivers/clk/samsung/clk-exynos5420.c
> @@ -1323,6 +1323,17 @@ static const struct samsung_pll_rate_table exynos5420_pll2550x_24mhz_tbl[] __ini
>  	PLL_35XX_RATE(24 * MHZ, 200000000,  200, 3, 3),
>  };
>  
> +static const struct samsung_pll_rate_table exynos5422_bpll_rate_table[] = {
> +	PLL_35XX_RATE(24 * MHZ, 825000000, 275, 4, 1),
> +	PLL_35XX_RATE(24 * MHZ, 728000000, 182, 3, 1),
> +	PLL_35XX_RATE(24 * MHZ, 633000000, 211, 4, 1),
> +	PLL_35XX_RATE(24 * MHZ, 543000000, 181, 2, 2),
> +	PLL_35XX_RATE(24 * MHZ, 413000000, 413, 6, 2),
> +	PLL_35XX_RATE(24 * MHZ, 275000000, 275, 3, 3),
> +	PLL_35XX_RATE(24 * MHZ, 206000000, 206, 3, 3),
> +	PLL_35XX_RATE(24 * MHZ, 165000000, 110, 2, 3),
> +};
> +
>  static const struct samsung_pll_rate_table exynos5420_epll_24mhz_tbl[] = {
>  	PLL_36XX_RATE(24 * MHZ, 600000000U, 100, 2, 1, 0),
>  	PLL_36XX_RATE(24 * MHZ, 400000000U, 200, 3, 2, 0),
> @@ -1465,7 +1476,7 @@ static void __init exynos5x_clk_init(struct device_node *np,
>  		exynos5x_plls[apll].rate_table = exynos5420_pll2550x_24mhz_tbl;
>  		exynos5x_plls[epll].rate_table = exynos5420_epll_24mhz_tbl;
>  		exynos5x_plls[kpll].rate_table = exynos5420_pll2550x_24mhz_tbl;
> -		exynos5x_plls[bpll].rate_table = exynos5420_pll2550x_24mhz_tbl;
> +		exynos5x_plls[bpll].rate_table = exynos5422_bpll_rate_table;

According to your previous reply, the released odroid-xu3 board by hardkernel
might be only CONFIG_SOC_EXYNOS5422_REV_0. Because the kernel configurattion
from hardkernel has 'CONFIG_SOC_EXYNOS5422_REV_0=y'. I'm ok about adding bpll rate_table.

But, just I have one question. I think that this bpll rate_table is for
only Exynos5422 series. Because the kernel of hardkernel used
driver/clk/samsung/clk-exynos5422.c instead of clk-exynos5420.c commonn driver.
It means that the clk-exynos5422.c of hardkernel's kernel support only Exynos5422
without any considering the Exynos5420 series. 

I think that it might need to check the soc version to use
bpll rate_table as following:

--- a/drivers/clk/samsung/clk-exynos5420.c
+++ b/drivers/clk/samsung/clk-exynos5420.c
@@ -1438,7 +1438,10 @@ static void __init exynos5x_clk_init(struct device_node *np,
                exynos5x_plls[apll].rate_table = exynos5420_pll2550x_24mhz_tbl;
                exynos5x_plls[epll].rate_table = exynos5420_epll_24mhz_tbl;
                exynos5x_plls[kpll].rate_table = exynos5420_pll2550x_24mhz_tbl;
-               exynos5x_plls[bpll].rate_table = exynos5422_bpll_rate_table;
+
+               if (soc == EXYNOS5800)
+                       exynos5x_plls[bpll].rate_table
+                               = exynos5422_bpll_rate_table;
        }


>  	}
>  
>  	samsung_clk_register_pll(ctx, exynos5x_plls, ARRAY_SIZE(exynos5x_plls),
> 


-- 
Best Regards,
Chanwoo Choi
Samsung Electronics

Re: [PATCH v6 03/10] clk: samsung: add BPLL rate table for Exynos 5422 SoC

[Lukasz Luba]

Hi Chanwoo,

On 5/2/19 7:15 AM, Chanwoo Choi wrote:
> Hi Lukasz,
> 
> On 19. 4. 19. 오후 11:19, Lukasz Luba wrote:
>> Add new table rate for BPLL for Exynos5422 SoC supporting Dynamic Memory
>> Controller frequencies for driver's DRAM timings.
>>
>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>> ---
>>   drivers/clk/samsung/clk-exynos5420.c | 13 ++++++++++++-
>>   1 file changed, 12 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
>> index d9e6653..ddee8bd 100644
>> --- a/drivers/clk/samsung/clk-exynos5420.c
>> +++ b/drivers/clk/samsung/clk-exynos5420.c
>> @@ -1323,6 +1323,17 @@ static const struct samsung_pll_rate_table exynos5420_pll2550x_24mhz_tbl[] __ini
>>   	PLL_35XX_RATE(24 * MHZ, 200000000,  200, 3, 3),
>>   };
>>   
>> +static const struct samsung_pll_rate_table exynos5422_bpll_rate_table[] = {
>> +	PLL_35XX_RATE(24 * MHZ, 825000000, 275, 4, 1),
>> +	PLL_35XX_RATE(24 * MHZ, 728000000, 182, 3, 1),
>> +	PLL_35XX_RATE(24 * MHZ, 633000000, 211, 4, 1),
>> +	PLL_35XX_RATE(24 * MHZ, 543000000, 181, 2, 2),
>> +	PLL_35XX_RATE(24 * MHZ, 413000000, 413, 6, 2),
>> +	PLL_35XX_RATE(24 * MHZ, 275000000, 275, 3, 3),
>> +	PLL_35XX_RATE(24 * MHZ, 206000000, 206, 3, 3),
>> +	PLL_35XX_RATE(24 * MHZ, 165000000, 110, 2, 3),
>> +};
>> +
>>   static const struct samsung_pll_rate_table exynos5420_epll_24mhz_tbl[] = {
>>   	PLL_36XX_RATE(24 * MHZ, 600000000U, 100, 2, 1, 0),
>>   	PLL_36XX_RATE(24 * MHZ, 400000000U, 200, 3, 2, 0),
>> @@ -1465,7 +1476,7 @@ static void __init exynos5x_clk_init(struct device_node *np,
>>   		exynos5x_plls[apll].rate_table = exynos5420_pll2550x_24mhz_tbl;
>>   		exynos5x_plls[epll].rate_table = exynos5420_epll_24mhz_tbl;
>>   		exynos5x_plls[kpll].rate_table = exynos5420_pll2550x_24mhz_tbl;
>> -		exynos5x_plls[bpll].rate_table = exynos5420_pll2550x_24mhz_tbl;
>> +		exynos5x_plls[bpll].rate_table = exynos5422_bpll_rate_table;
> 
> According to your previous reply, the released odroid-xu3 board by hardkernel
> might be only CONFIG_SOC_EXYNOS5422_REV_0. Because the kernel configurattion
> from hardkernel has 'CONFIG_SOC_EXYNOS5422_REV_0=y'. I'm ok about adding bpll rate_table.
> 
> But, just I have one question. I think that this bpll rate_table is for
> only Exynos5422 series. Because the kernel of hardkernel used
> driver/clk/samsung/clk-exynos5422.c instead of clk-exynos5420.c commonn driver.
> It means that the clk-exynos5422.c of hardkernel's kernel support only Exynos5422
> without any considering the Exynos5420 series.
> 
> I think that it might need to check the soc version to use
> bpll rate_table as following:
Fair enough.
> 
> --- a/drivers/clk/samsung/clk-exynos5420.c
> +++ b/drivers/clk/samsung/clk-exynos5420.c
> @@ -1438,7 +1438,10 @@ static void __init exynos5x_clk_init(struct device_node *np,
>                  exynos5x_plls[apll].rate_table = exynos5420_pll2550x_24mhz_tbl;
>                  exynos5x_plls[epll].rate_table = exynos5420_epll_24mhz_tbl;
>                  exynos5x_plls[kpll].rate_table = exynos5420_pll2550x_24mhz_tbl;
> -               exynos5x_plls[bpll].rate_table = exynos5422_bpll_rate_table;
> +
> +               if (soc == EXYNOS5800)
> +                       exynos5x_plls[bpll].rate_table
> +                               = exynos5422_bpll_rate_table;
>          }
> 
I will add this check. Thank you.

Regards,
Lukasz
> 
>>   	}
>>   
>>   	samsung_clk_register_pll(ctx, exynos5x_plls, ARRAY_SIZE(exynos5x_plls),
>>
> 
> 

[PATCH v6 04/10] Documentation: dt: device tree bindings for LPDDR3 memories

[Lukasz Luba]

The device tree bindings for LPDDR3 SDRAM memories.

For specifying the AC timing parameters of the memory device
the 'lpddr3' binding uses binding 'lpddr2-timings'.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 .../devicetree/bindings/lpddr3/lpddr3-timings.txt  | 57 +++++++++++++
 .../devicetree/bindings/lpddr3/lpddr3.txt          | 93 ++++++++++++++++++++++
 2 files changed, 150 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
 create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3.txt

diff --git a/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt b/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
new file mode 100644
index 0000000..ebf3e00
--- /dev/null
+++ b/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
@@ -0,0 +1,57 @@
+* AC timing parameters of LPDDR3 memories for a given speed-bin.
+* The structures are based on LPDDR2 and extended where needed.
+
+Required properties:
+- compatible : Should be "jedec,lpddr3-timings"
+- min-freq : minimum DDR clock frequency for the speed-bin. Type is <u32>
+- max-freq : maximum DDR clock frequency for the speed-bin. Type is <u32>
+
+Optional properties:
+
+The following properties represent AC timing parameters from the memory
+data-sheet of the device for a given speed-bin. All these properties are
+of type <u32> and the default unit is ps (pico seconds).
+- tRFC
+- tRRD
+- tRPab
+- tRPpb
+- tRCD
+- tRC
+- tRAS
+- tWTR
+- tWR
+- tRTP
+- tW2W-C2C
+- tR2R-C2C
+- tFAW
+- tXSR
+- tXP
+- tCKE
+- tCKESR
+- tMRD
+
+Example:
+
+timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@0 {
+	compatible	= "jedec,lpddr3-timings";
+	min-freq	= <100000000>;
+	max-freq	= <800000000>;
+	tRFC		= <65000>;
+	tRRD		= <6000>;
+	tRPab		= <12000>;
+	tRPpb		= <12000>;
+	tRCD		= <10000>;
+	tRC		= <33750>;
+	tRAS		= <23000>;
+	tWTR		= <3750>;
+	tWR		= <7500>;
+	tRTP		= <3750>;
+	tW2W-C2C	= <0>;
+	tR2R-C2C	= <0>;
+	tFAW		= <25000>;
+	tXSR		= <70000>;
+	tXP		= <3750>;
+	tCKE		= <3750>;
+	tCKESR		= <3750>;
+	tMRD		= <7000>;
+};
diff --git a/Documentation/devicetree/bindings/lpddr3/lpddr3.txt b/Documentation/devicetree/bindings/lpddr3/lpddr3.txt
new file mode 100644
index 0000000..fc7875c
--- /dev/null
+++ b/Documentation/devicetree/bindings/lpddr3/lpddr3.txt
@@ -0,0 +1,93 @@
+* LPDDR3 SDRAM memories compliant to JEDEC JESD209-2
+
+Required properties:
+- compatible : Should be  - "jedec,lpddr3"
+- density  : <u32> representing density in Mb (Mega bits)
+- io-width : <u32> representing bus width. Possible values are 8, 16, 32, 64
+
+Optional properties:
+
+The following optional properties represent the minimum value of some AC
+timing parameters of the DDR device in terms of number of clock cycles.
+These values shall be obtained from the device data-sheet.
+- tRFC-min-tck
+- tRRD-min-tck
+- tRPab-min-tck
+- tRPpb-min-tck
+- tRCD-min-tck
+- tRC-min-tck
+- tRAS-min-tck
+- tWTR-min-tck
+- tWR-min-tck
+- tRTP-min-tck
+- tW2W-C2C-min-tck
+- tR2R-C2C-min-tck
+- tWL-min-tck
+- tDQSCK-min-tck
+- tRL-min-tck
+- tFAW-min-tck
+- tXSR-min-tck
+- tXP-min-tck
+- tCKE-min-tck
+- tCKESR-min-tck
+- tMRD-min-tck
+
+Child nodes:
+- The lpddr3 node may have one or more child nodes of type "lpddr3-timings".
+  "lpddr3-timings" provides AC timing parameters of the device for
+  a given speed-bin. Please see Documentation/devicetree/
+  bindings/lpddr3/lpddr3-timings.txt for more information on "lpddr3-timings"
+
+Example:
+
+samsung_K3QF2F20DB: lpddr3 {
+	compatible	= "Samsung,K3QF2F20DB","jedec,lpddr3";
+	density		= <16384>;
+	io-width	= <32>;
+
+	tRFC-min-tck		= <17>;
+	tRRD-min-tck		= <2>;
+	tRPab-min-tck		= <2>;
+	tRPpb-min-tck		= <2>;
+	tRCD-min-tck		= <3>;
+	tRC-min-tck		= <6>;
+	tRAS-min-tck		= <5>;
+	tWTR-min-tck		= <2>;
+	tWR-min-tck		= <7>;
+	tRTP-min-tck		= <2>;
+	tW2W-C2C-min-tck	= <0>;
+	tR2R-C2C-min-tck	= <0>;
+	tWL-min-tck		= <8>;
+	tDQSCK-min-tck		= <5>;
+	tRL-min-tck		= <14>;
+	tFAW-min-tck		= <5>;
+	tXSR-min-tck		= <12>;
+	tXP-min-tck		= <2>;
+	tCKE-min-tck		= <2>;
+	tCKESR-min-tck		= <2>;
+	tMRD-min-tck		= <5>;
+
+	timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@0 {
+		compatible	= "jedec,lpddr3-timings";
+		min-freq	= <100000000>;
+		max-freq	= <800000000>;
+		tRFC		= <65000>;
+		tRRD		= <6000>;
+		tRPab		= <12000>;
+		tRPpb		= <12000>;
+		tRCD		= <10000>;
+		tRC		= <33750>;
+		tRAS		= <23000>;
+		tWTR		= <3750>;
+		tWR		= <7500>;
+		tRTP		= <3750>;
+		tW2W-C2C	= <0>;
+		tR2R-C2C	= <0>;
+		tFAW		= <25000>;
+		tXSR		= <70000>;
+		tXP		= <3750>;
+		tCKE		= <3750>;
+		tCKESR		= <3750>;
+		tMRD		= <7000>;
+	};
+}
-- 
2.7.4

Re: [PATCH v6 04/10] Documentation: dt: device tree bindings for LPDDR3 memories

[Rob Herring]

On Fri, Apr 19, 2019 at 04:19:22PM +0200, Lukasz Luba wrote:
> The device tree bindings for LPDDR3 SDRAM memories.
> 
> For specifying the AC timing parameters of the memory device
> the 'lpddr3' binding uses binding 'lpddr2-timings'.
> 
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  .../devicetree/bindings/lpddr3/lpddr3-timings.txt  | 57 +++++++++++++
>  .../devicetree/bindings/lpddr3/lpddr3.txt          | 93 ++++++++++++++++++++++

Please rename the lpddr2 directory to 'ddr' and add these to it.

Maybe whatever properties are common should be put in a common doc.

>  2 files changed, 150 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
>  create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3.txt
> 
> diff --git a/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt b/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
> new file mode 100644
> index 0000000..ebf3e00
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
> @@ -0,0 +1,57 @@
> +* AC timing parameters of LPDDR3 memories for a given speed-bin.
> +* The structures are based on LPDDR2 and extended where needed.
> +
> +Required properties:
> +- compatible : Should be "jedec,lpddr3-timings"
> +- min-freq : minimum DDR clock frequency for the speed-bin. Type is <u32>
> +- max-freq : maximum DDR clock frequency for the speed-bin. Type is <u32>
> +
> +Optional properties:
> +
> +The following properties represent AC timing parameters from the memory
> +data-sheet of the device for a given speed-bin. All these properties are
> +of type <u32> and the default unit is ps (pico seconds).
> +- tRFC
> +- tRRD
> +- tRPab
> +- tRPpb
> +- tRCD
> +- tRC
> +- tRAS
> +- tWTR
> +- tWR
> +- tRTP
> +- tW2W-C2C
> +- tR2R-C2C
> +- tFAW
> +- tXSR
> +- tXP
> +- tCKE
> +- tCKESR
> +- tMRD
> +
> +Example:
> +
> +timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@0 {

Since the lpddr2 version was written, we've gotten stricter about 
allowing unit-address without reg property. Perhaps 'reg' should be the 
max-freq instead.

> +	compatible	= "jedec,lpddr3-timings";
> +	min-freq	= <100000000>;
> +	max-freq	= <800000000>;
> +	tRFC		= <65000>;
> +	tRRD		= <6000>;
> +	tRPab		= <12000>;
> +	tRPpb		= <12000>;
> +	tRCD		= <10000>;
> +	tRC		= <33750>;
> +	tRAS		= <23000>;
> +	tWTR		= <3750>;
> +	tWR		= <7500>;
> +	tRTP		= <3750>;
> +	tW2W-C2C	= <0>;
> +	tR2R-C2C	= <0>;
> +	tFAW		= <25000>;
> +	tXSR		= <70000>;
> +	tXP		= <3750>;
> +	tCKE		= <3750>;
> +	tCKESR		= <3750>;
> +	tMRD		= <7000>;
> +};
> diff --git a/Documentation/devicetree/bindings/lpddr3/lpddr3.txt b/Documentation/devicetree/bindings/lpddr3/lpddr3.txt
> new file mode 100644
> index 0000000..fc7875c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/lpddr3/lpddr3.txt
> @@ -0,0 +1,93 @@
> +* LPDDR3 SDRAM memories compliant to JEDEC JESD209-2

That's an LPDDR2 spec.

> +
> +Required properties:
> +- compatible : Should be  - "jedec,lpddr3"
> +- density  : <u32> representing density in Mb (Mega bits)
> +- io-width : <u32> representing bus width. Possible values are 8, 16, 32, 64
> +
> +Optional properties:
> +
> +The following optional properties represent the minimum value of some AC
> +timing parameters of the DDR device in terms of number of clock cycles.
> +These values shall be obtained from the device data-sheet.
> +- tRFC-min-tck
> +- tRRD-min-tck
> +- tRPab-min-tck
> +- tRPpb-min-tck
> +- tRCD-min-tck
> +- tRC-min-tck
> +- tRAS-min-tck
> +- tWTR-min-tck
> +- tWR-min-tck
> +- tRTP-min-tck
> +- tW2W-C2C-min-tck
> +- tR2R-C2C-min-tck
> +- tWL-min-tck
> +- tDQSCK-min-tck
> +- tRL-min-tck
> +- tFAW-min-tck
> +- tXSR-min-tck
> +- tXP-min-tck
> +- tCKE-min-tck
> +- tCKESR-min-tck
> +- tMRD-min-tck
> +
> +Child nodes:
> +- The lpddr3 node may have one or more child nodes of type "lpddr3-timings".
> +  "lpddr3-timings" provides AC timing parameters of the device for
> +  a given speed-bin. Please see Documentation/devicetree/
> +  bindings/lpddr3/lpddr3-timings.txt for more information on "lpddr3-timings"
> +
> +Example:
> +
> +samsung_K3QF2F20DB: lpddr3 {
> +	compatible	= "Samsung,K3QF2F20DB","jedec,lpddr3";
> +	density		= <16384>;
> +	io-width	= <32>;
> +
> +	tRFC-min-tck		= <17>;
> +	tRRD-min-tck		= <2>;
> +	tRPab-min-tck		= <2>;
> +	tRPpb-min-tck		= <2>;
> +	tRCD-min-tck		= <3>;
> +	tRC-min-tck		= <6>;
> +	tRAS-min-tck		= <5>;
> +	tWTR-min-tck		= <2>;
> +	tWR-min-tck		= <7>;
> +	tRTP-min-tck		= <2>;
> +	tW2W-C2C-min-tck	= <0>;
> +	tR2R-C2C-min-tck	= <0>;
> +	tWL-min-tck		= <8>;
> +	tDQSCK-min-tck		= <5>;
> +	tRL-min-tck		= <14>;
> +	tFAW-min-tck		= <5>;
> +	tXSR-min-tck		= <12>;
> +	tXP-min-tck		= <2>;
> +	tCKE-min-tck		= <2>;
> +	tCKESR-min-tck		= <2>;
> +	tMRD-min-tck		= <5>;
> +
> +	timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@0 {
> +		compatible	= "jedec,lpddr3-timings";
> +		min-freq	= <100000000>;
> +		max-freq	= <800000000>;
> +		tRFC		= <65000>;
> +		tRRD		= <6000>;
> +		tRPab		= <12000>;
> +		tRPpb		= <12000>;
> +		tRCD		= <10000>;
> +		tRC		= <33750>;
> +		tRAS		= <23000>;
> +		tWTR		= <3750>;
> +		tWR		= <7500>;
> +		tRTP		= <3750>;
> +		tW2W-C2C	= <0>;
> +		tR2R-C2C	= <0>;
> +		tFAW		= <25000>;
> +		tXSR		= <70000>;
> +		tXP		= <3750>;
> +		tCKE		= <3750>;
> +		tCKESR		= <3750>;
> +		tMRD		= <7000>;
> +	};
> +}
> -- 
> 2.7.4
> 

Re: [PATCH v6 04/10] Documentation: dt: device tree bindings for LPDDR3 memories

[Lukasz Luba]

Hi Rob,

On 4/25/19 9:51 PM, Rob Herring wrote:
> On Fri, Apr 19, 2019 at 04:19:22PM +0200, Lukasz Luba wrote:
>> The device tree bindings for LPDDR3 SDRAM memories.
>>
>> For specifying the AC timing parameters of the memory device
>> the 'lpddr3' binding uses binding 'lpddr2-timings'.
>>
>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>> ---
>>   .../devicetree/bindings/lpddr3/lpddr3-timings.txt  | 57 +++++++++++++
>>   .../devicetree/bindings/lpddr3/lpddr3.txt          | 93 ++++++++++++++++++++++
> 
> Please rename the lpddr2 directory to 'ddr' and add these to it.
OK, I will rename it in the nex patch set.
> 
> Maybe whatever properties are common should be put in a common doc.
There are maybe a few common properties, but I would not dare to merge
lpddr2 and lpddr3 before consulting it with TI engineers who made
LPDDR2 support.
Could we work on a common file after the patch set got merged?
> 
>>   2 files changed, 150 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
>>   create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3.txt
>>
>> diff --git a/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt b/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
>> new file mode 100644
>> index 0000000..ebf3e00
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
>> @@ -0,0 +1,57 @@
>> +* AC timing parameters of LPDDR3 memories for a given speed-bin.
>> +* The structures are based on LPDDR2 and extended where needed.
>> +
>> +Required properties:
>> +- compatible : Should be "jedec,lpddr3-timings"
>> +- min-freq : minimum DDR clock frequency for the speed-bin. Type is <u32>
>> +- max-freq : maximum DDR clock frequency for the speed-bin. Type is <u32>
>> +
>> +Optional properties:
>> +
>> +The following properties represent AC timing parameters from the memory
>> +data-sheet of the device for a given speed-bin. All these properties are
>> +of type <u32> and the default unit is ps (pico seconds).
>> +- tRFC
>> +- tRRD
>> +- tRPab
>> +- tRPpb
>> +- tRCD
>> +- tRC
>> +- tRAS
>> +- tWTR
>> +- tWR
>> +- tRTP
>> +- tW2W-C2C
>> +- tR2R-C2C
>> +- tFAW
>> +- tXSR
>> +- tXP
>> +- tCKE
>> +- tCKESR
>> +- tMRD
>> +
>> +Example:
>> +
>> +timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@0 {
> 
> Since the lpddr2 version was written, we've gotten stricter about
> allowing unit-address without reg property. Perhaps 'reg' should be the
> max-freq instead.
OK, so I will rename 'max-freq' to 'reg' and add a comment with:
'/* workaround: it shows max-freq */
Does it make sense?
> 
>> +	compatible	= "jedec,lpddr3-timings";
>> +	min-freq	= <100000000>;
>> +	max-freq	= <800000000>;
>> +	tRFC		= <65000>;
>> +	tRRD		= <6000>;
>> +	tRPab		= <12000>;
>> +	tRPpb		= <12000>;
>> +	tRCD		= <10000>;
>> +	tRC		= <33750>;
>> +	tRAS		= <23000>;
>> +	tWTR		= <3750>;
>> +	tWR		= <7500>;
>> +	tRTP		= <3750>;
>> +	tW2W-C2C	= <0>;
>> +	tR2R-C2C	= <0>;
>> +	tFAW		= <25000>;
>> +	tXSR		= <70000>;
>> +	tXP		= <3750>;
>> +	tCKE		= <3750>;
>> +	tCKESR		= <3750>;
>> +	tMRD		= <7000>;
>> +};
>> diff --git a/Documentation/devicetree/bindings/lpddr3/lpddr3.txt b/Documentation/devicetree/bindings/lpddr3/lpddr3.txt
>> new file mode 100644
>> index 0000000..fc7875c
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/lpddr3/lpddr3.txt
>> @@ -0,0 +1,93 @@
>> +* LPDDR3 SDRAM memories compliant to JEDEC JESD209-2
> 
> That's an LPDDR2 spec.
Right, should be JESD209-3C.

Thank you for the review.

Regards,
Lukasz
> 
>> +
>> +Required properties:
>> +- compatible : Should be  - "jedec,lpddr3"
>> +- density  : <u32> representing density in Mb (Mega bits)
>> +- io-width : <u32> representing bus width. Possible values are 8, 16, 32, 64
>> +
>> +Optional properties:
>> +
>> +The following optional properties represent the minimum value of some AC
>> +timing parameters of the DDR device in terms of number of clock cycles.
>> +These values shall be obtained from the device data-sheet.
>> +- tRFC-min-tck
>> +- tRRD-min-tck
>> +- tRPab-min-tck
>> +- tRPpb-min-tck
>> +- tRCD-min-tck
>> +- tRC-min-tck
>> +- tRAS-min-tck
>> +- tWTR-min-tck
>> +- tWR-min-tck
>> +- tRTP-min-tck
>> +- tW2W-C2C-min-tck
>> +- tR2R-C2C-min-tck
>> +- tWL-min-tck
>> +- tDQSCK-min-tck
>> +- tRL-min-tck
>> +- tFAW-min-tck
>> +- tXSR-min-tck
>> +- tXP-min-tck
>> +- tCKE-min-tck
>> +- tCKESR-min-tck
>> +- tMRD-min-tck
>> +
>> +Child nodes:
>> +- The lpddr3 node may have one or more child nodes of type "lpddr3-timings".
>> +  "lpddr3-timings" provides AC timing parameters of the device for
>> +  a given speed-bin. Please see Documentation/devicetree/
>> +  bindings/lpddr3/lpddr3-timings.txt for more information on "lpddr3-timings"
>> +
>> +Example:
>> +
>> +samsung_K3QF2F20DB: lpddr3 {
>> +	compatible	= "Samsung,K3QF2F20DB","jedec,lpddr3";
>> +	density		= <16384>;
>> +	io-width	= <32>;
>> +
>> +	tRFC-min-tck		= <17>;
>> +	tRRD-min-tck		= <2>;
>> +	tRPab-min-tck		= <2>;
>> +	tRPpb-min-tck		= <2>;
>> +	tRCD-min-tck		= <3>;
>> +	tRC-min-tck		= <6>;
>> +	tRAS-min-tck		= <5>;
>> +	tWTR-min-tck		= <2>;
>> +	tWR-min-tck		= <7>;
>> +	tRTP-min-tck		= <2>;
>> +	tW2W-C2C-min-tck	= <0>;
>> +	tR2R-C2C-min-tck	= <0>;
>> +	tWL-min-tck		= <8>;
>> +	tDQSCK-min-tck		= <5>;
>> +	tRL-min-tck		= <14>;
>> +	tFAW-min-tck		= <5>;
>> +	tXSR-min-tck		= <12>;
>> +	tXP-min-tck		= <2>;
>> +	tCKE-min-tck		= <2>;
>> +	tCKESR-min-tck		= <2>;
>> +	tMRD-min-tck		= <5>;
>> +
>> +	timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@0 {
>> +		compatible	= "jedec,lpddr3-timings";
>> +		min-freq	= <100000000>;
>> +		max-freq	= <800000000>;
>> +		tRFC		= <65000>;
>> +		tRRD		= <6000>;
>> +		tRPab		= <12000>;
>> +		tRPpb		= <12000>;
>> +		tRCD		= <10000>;
>> +		tRC		= <33750>;
>> +		tRAS		= <23000>;
>> +		tWTR		= <3750>;
>> +		tWR		= <7500>;
>> +		tRTP		= <3750>;
>> +		tW2W-C2C	= <0>;
>> +		tR2R-C2C	= <0>;
>> +		tFAW		= <25000>;
>> +		tXSR		= <70000>;
>> +		tXP		= <3750>;
>> +		tCKE		= <3750>;
>> +		tCKESR		= <3750>;
>> +		tMRD		= <7000>;
>> +	};
>> +}
>> -- 
>> 2.7.4
>>
> 
> 

Re: [PATCH v6 04/10] Documentation: dt: device tree bindings for LPDDR3 memories

[Rob Herring]

On Mon, Apr 29, 2019 at 7:05 AM Lukasz Luba <l.luba@partner.samsung.com> wrote:
>
> Hi Rob,
>
> On 4/25/19 9:51 PM, Rob Herring wrote:
> > On Fri, Apr 19, 2019 at 04:19:22PM +0200, Lukasz Luba wrote:
> >> The device tree bindings for LPDDR3 SDRAM memories.
> >>
> >> For specifying the AC timing parameters of the memory device
> >> the 'lpddr3' binding uses binding 'lpddr2-timings'.
> >>
> >> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> >> ---
> >>   .../devicetree/bindings/lpddr3/lpddr3-timings.txt  | 57 +++++++++++++
> >>   .../devicetree/bindings/lpddr3/lpddr3.txt          | 93 ++++++++++++++++++++++
> >
> > Please rename the lpddr2 directory to 'ddr' and add these to it.
> OK, I will rename it in the nex patch set.
> >
> > Maybe whatever properties are common should be put in a common doc.
> There are maybe a few common properties, but I would not dare to merge
> lpddr2 and lpddr3 before consulting it with TI engineers who made
> LPDDR2 support.

Why not. You aren't changing anything. Just rearranging.

> Could we work on a common file after the patch set got merged?

Yes, but please still move everything to a common directory.

> >
> >>   2 files changed, 150 insertions(+)
> >>   create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
> >>   create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3.txt
> >>
> >> diff --git a/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt b/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
> >> new file mode 100644
> >> index 0000000..ebf3e00
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
> >> @@ -0,0 +1,57 @@
> >> +* AC timing parameters of LPDDR3 memories for a given speed-bin.
> >> +* The structures are based on LPDDR2 and extended where needed.
> >> +
> >> +Required properties:
> >> +- compatible : Should be "jedec,lpddr3-timings"
> >> +- min-freq : minimum DDR clock frequency for the speed-bin. Type is <u32>
> >> +- max-freq : maximum DDR clock frequency for the speed-bin. Type is <u32>
> >> +
> >> +Optional properties:
> >> +
> >> +The following properties represent AC timing parameters from the memory
> >> +data-sheet of the device for a given speed-bin. All these properties are
> >> +of type <u32> and the default unit is ps (pico seconds).
> >> +- tRFC
> >> +- tRRD
> >> +- tRPab
> >> +- tRPpb
> >> +- tRCD
> >> +- tRC
> >> +- tRAS
> >> +- tWTR
> >> +- tWR
> >> +- tRTP
> >> +- tW2W-C2C
> >> +- tR2R-C2C
> >> +- tFAW
> >> +- tXSR
> >> +- tXP
> >> +- tCKE
> >> +- tCKESR
> >> +- tMRD
> >> +
> >> +Example:
> >> +
> >> +timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@0 {
> >
> > Since the lpddr2 version was written, we've gotten stricter about
> > allowing unit-address without reg property. Perhaps 'reg' should be the
> > max-freq instead.
> OK, so I will rename 'max-freq' to 'reg' and add a comment with:
> '/* workaround: it shows max-freq */
> Does it make sense?

Sure.

Rob

Re: [PATCH v6 04/10] Documentation: dt: device tree bindings for LPDDR3 memories

[Lukasz Luba]

Hi Rob,

On 4/29/19 6:36 PM, Rob Herring wrote:
> On Mon, Apr 29, 2019 at 7:05 AM Lukasz Luba <l.luba@partner.samsung.com> wrote:
>>
>> Hi Rob,
>>
>> On 4/25/19 9:51 PM, Rob Herring wrote:
>>> On Fri, Apr 19, 2019 at 04:19:22PM +0200, Lukasz Luba wrote:
>>>> The device tree bindings for LPDDR3 SDRAM memories.
>>>>
>>>> For specifying the AC timing parameters of the memory device
>>>> the 'lpddr3' binding uses binding 'lpddr2-timings'.
>>>>
>>>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>>>> ---
>>>>    .../devicetree/bindings/lpddr3/lpddr3-timings.txt  | 57 +++++++++++++
>>>>    .../devicetree/bindings/lpddr3/lpddr3.txt          | 93 ++++++++++++++++++++++
>>>
>>> Please rename the lpddr2 directory to 'ddr' and add these to it.
>> OK, I will rename it in the nex patch set.
>>>
>>> Maybe whatever properties are common should be put in a common doc.
>> There are maybe a few common properties, but I would not dare to merge
>> lpddr2 and lpddr3 before consulting it with TI engineers who made
>> LPDDR2 support.
> 
> Why not. You aren't changing anything. Just rearranging.
True.
> 
>> Could we work on a common file after the patch set got merged?
> 
> Yes, but please still move everything to a common directory.
OK, I am currently working on it and moving these lpddr* files into
Documentation/devicetree/bindings/ddr/
Then after acceptance I will find the common stuff and do the merge.
> 
>>>
>>>>    2 files changed, 150 insertions(+)
>>>>    create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
>>>>    create mode 100644 Documentation/devicetree/bindings/lpddr3/lpddr3.txt
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt b/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
>>>> new file mode 100644
>>>> index 0000000..ebf3e00
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/lpddr3/lpddr3-timings.txt
>>>> @@ -0,0 +1,57 @@
>>>> +* AC timing parameters of LPDDR3 memories for a given speed-bin.
>>>> +* The structures are based on LPDDR2 and extended where needed.
>>>> +
>>>> +Required properties:
>>>> +- compatible : Should be "jedec,lpddr3-timings"
>>>> +- min-freq : minimum DDR clock frequency for the speed-bin. Type is <u32>
>>>> +- max-freq : maximum DDR clock frequency for the speed-bin. Type is <u32>
>>>> +
>>>> +Optional properties:
>>>> +
>>>> +The following properties represent AC timing parameters from the memory
>>>> +data-sheet of the device for a given speed-bin. All these properties are
>>>> +of type <u32> and the default unit is ps (pico seconds).
>>>> +- tRFC
>>>> +- tRRD
>>>> +- tRPab
>>>> +- tRPpb
>>>> +- tRCD
>>>> +- tRC
>>>> +- tRAS
>>>> +- tWTR
>>>> +- tWR
>>>> +- tRTP
>>>> +- tW2W-C2C
>>>> +- tR2R-C2C
>>>> +- tFAW
>>>> +- tXSR
>>>> +- tXP
>>>> +- tCKE
>>>> +- tCKESR
>>>> +- tMRD
>>>> +
>>>> +Example:
>>>> +
>>>> +timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@0 {
>>>
>>> Since the lpddr2 version was written, we've gotten stricter about
>>> allowing unit-address without reg property. Perhaps 'reg' should be the
>>> max-freq instead.
>> OK, so I will rename 'max-freq' to 'reg' and add a comment with:
>> '/* workaround: it shows max-freq */
>> Does it make sense?
> 
> Sure.
OK. Thank you.

Regards,
Lukasz
> 
> Rob
> 
> 

Re: [PATCH v6 04/10] Documentation: dt: device tree bindings for LPDDR3 memories

[Rob Herring]

On Fri, Apr 19, 2019 at 04:19:22PM +0200, Lukasz Luba wrote:
> The device tree bindings for LPDDR3 SDRAM memories.

Also, 'dt-bindings: ddr: ' for the subject. You've got a mixture of 
subjects with no consistency.

> 
> For specifying the AC timing parameters of the memory device
> the 'lpddr3' binding uses binding 'lpddr2-timings'.
> 
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>

Re: [PATCH v6 04/10] Documentation: dt: device tree bindings for LPDDR3 memories

[Lukasz Luba]

On 4/25/19 9:53 PM, Rob Herring wrote:
> On Fri, Apr 19, 2019 at 04:19:22PM +0200, Lukasz Luba wrote:
>> The device tree bindings for LPDDR3 SDRAM memories.
> 
> Also, 'dt-bindings: ddr: ' for the subject. You've got a mixture of
> subjects with no consistency.
Right, I will change it.
> 
>>
>> For specifying the AC timing parameters of the memory device
>> the 'lpddr3' binding uses binding 'lpddr2-timings'.
>>
>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> 
> 

[PATCH v6 05/10] drivers: memory: extend of_memory by LPDDR3 support

[Lukasz Luba]

The patch adds AC timings information needed to support LPDDR3 and memory
controllers. The structure is used in of_memory and currently in Exynos
5422 DMC. Add parsing data needed for LPDDR3 support.
It is currently used in Exynos5422 Dynamic Memory Controller.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 drivers/memory/of_memory.c | 125 +++++++++++++++++++++++++++++++++++++++++++++
 drivers/memory/of_memory.h |  20 +++++++-
 include/memory/jedec_ddr.h |  62 ++++++++++++++++++++++
 3 files changed, 206 insertions(+), 1 deletion(-)

diff --git a/drivers/memory/of_memory.c b/drivers/memory/of_memory.c
index 2f5ed73..7a77174 100644
--- a/drivers/memory/of_memory.c
+++ b/drivers/memory/of_memory.c
@@ -152,3 +152,128 @@ const struct lpddr2_timings *of_get_ddr_timings(struct device_node *np_ddr,
 	return lpddr2_jedec_timings;
 }
 EXPORT_SYMBOL(of_get_ddr_timings);
+
+
+const struct lpddr3_min_tck *of_lpddr3_get_min_tck(struct device_node *np,
+						   struct device *dev)
+{
+	int			ret = 0;
+	struct lpddr3_min_tck	*min;
+
+	min = devm_kzalloc(dev, sizeof(*min), GFP_KERNEL);
+	if (!min)
+		goto default_min_tck;
+
+	ret |= of_property_read_u32(np, "tRFC-min-tck", &min->tRFC);
+	ret |= of_property_read_u32(np, "tRRD-min-tck", &min->tRRD);
+	ret |= of_property_read_u32(np, "tRPab-min-tck", &min->tRPab);
+	ret |= of_property_read_u32(np, "tRPpb-min-tck", &min->tRPpb);
+	ret |= of_property_read_u32(np, "tRCD-min-tck", &min->tRCD);
+	ret |= of_property_read_u32(np, "tRC-min-tck", &min->tRC);
+	ret |= of_property_read_u32(np, "tRAS-min-tck", &min->tRAS);
+	ret |= of_property_read_u32(np, "tWTR-min-tck", &min->tWTR);
+	ret |= of_property_read_u32(np, "tWR-min-tck", &min->tWR);
+	ret |= of_property_read_u32(np, "tRTP-min-tck", &min->tRTP);
+	ret |= of_property_read_u32(np, "tW2W-C2C-min-tck", &min->tW2W_C2C);
+	ret |= of_property_read_u32(np, "tR2R-C2C-min-tck", &min->tR2R_C2C);
+	ret |= of_property_read_u32(np, "tWL-min-tck", &min->tWL);
+	ret |= of_property_read_u32(np, "tDQSCK-min-tck", &min->tDQSCK);
+	ret |= of_property_read_u32(np, "tRL-min-tck", &min->tRL);
+	ret |= of_property_read_u32(np, "tFAW-min-tck", &min->tFAW);
+	ret |= of_property_read_u32(np, "tXSR-min-tck", &min->tXSR);
+	ret |= of_property_read_u32(np, "tXP-min-tck", &min->tXP);
+	ret |= of_property_read_u32(np, "tCKE-min-tck", &min->tCKE);
+	ret |= of_property_read_u32(np, "tCKESR-min-tck", &min->tCKESR);
+	ret |= of_property_read_u32(np, "tMRD-min-tck", &min->tMRD);
+
+	if (ret) {
+		dev_warn(dev, "%s: errors while parsing min-tck values\n",
+			 __func__);
+		devm_kfree(dev, min);
+		goto default_min_tck;
+	}
+
+	return min;
+
+default_min_tck:
+	dev_warn(dev, "%s: using default min-tck values\n", __func__);
+	return NULL;
+}
+EXPORT_SYMBOL(of_lpddr3_get_min_tck);
+
+static int of_lpddr3_do_get_timings(struct device_node *np,
+				    struct lpddr3_timings *tim)
+{
+	int ret;
+
+	ret = of_property_read_u32(np, "max-freq", &tim->max_freq);
+	ret |= of_property_read_u32(np, "min-freq", &tim->min_freq);
+	ret |= of_property_read_u32(np, "tRFC", &tim->tRFC);
+	ret |= of_property_read_u32(np, "tRRD", &tim->tRRD);
+	ret |= of_property_read_u32(np, "tRPab", &tim->tRPab);
+	ret |= of_property_read_u32(np, "tRPpb", &tim->tRPpb);
+	ret |= of_property_read_u32(np, "tRCD", &tim->tRCD);
+	ret |= of_property_read_u32(np, "tRC", &tim->tRC);
+	ret |= of_property_read_u32(np, "tRAS", &tim->tRAS);
+	ret |= of_property_read_u32(np, "tWTR", &tim->tWTR);
+	ret |= of_property_read_u32(np, "tWR", &tim->tWR);
+	ret |= of_property_read_u32(np, "tRTP", &tim->tRTP);
+	ret |= of_property_read_u32(np, "tW2W-C2C", &tim->tW2W_C2C);
+	ret |= of_property_read_u32(np, "tR2R-C2C", &tim->tR2R_C2C);
+	ret |= of_property_read_u32(np, "tFAW", &tim->tFAW);
+	ret |= of_property_read_u32(np, "tXSR", &tim->tXSR);
+	ret |= of_property_read_u32(np, "tXP", &tim->tXP);
+	ret |= of_property_read_u32(np, "tCKE", &tim->tCKE);
+	ret |= of_property_read_u32(np, "tCKESR", &tim->tCKESR);
+	ret |= of_property_read_u32(np, "tMRD", &tim->tMRD);
+
+	return ret;
+}
+
+const struct lpddr3_timings *of_lpddr3_get_ddr_timings(struct device_node *np_ddr,
+		struct device *dev, u32 device_type, u32 *nr_frequencies)
+{
+	struct lpddr3_timings	*timings = NULL;
+	u32			arr_sz = 0, i = 0;
+	struct device_node	*np_tim;
+	char			*tim_compat = NULL;
+
+	switch (device_type) {
+	case DDR_TYPE_LPDDR3:
+		tim_compat = "jedec,lpddr3-timings";
+		break;
+	default:
+		dev_warn(dev, "%s: un-supported memory type\n", __func__);
+	}
+
+	for_each_child_of_node(np_ddr, np_tim)
+		if (of_device_is_compatible(np_tim, tim_compat))
+			arr_sz++;
+
+	if (arr_sz)
+		timings = devm_kcalloc(dev, arr_sz, sizeof(*timings),
+				       GFP_KERNEL);
+
+	if (!timings)
+		goto default_timings;
+
+	for_each_child_of_node(np_ddr, np_tim) {
+		if (of_device_is_compatible(np_tim, tim_compat)) {
+			if (of_lpddr3_do_get_timings(np_tim, &timings[i])) {
+				devm_kfree(dev, timings);
+				goto default_timings;
+			}
+			i++;
+		}
+	}
+
+	*nr_frequencies = arr_sz;
+
+	return timings;
+
+default_timings:
+	dev_warn(dev, "%s: using default timings\n", __func__);
+	*nr_frequencies = 0;
+	return NULL;
+}
+EXPORT_SYMBOL(of_lpddr3_get_ddr_timings);
diff --git a/drivers/memory/of_memory.h b/drivers/memory/of_memory.h
index ef2514f..8cf2ce6 100644
--- a/drivers/memory/of_memory.h
+++ b/drivers/memory/of_memory.h
@@ -18,6 +18,11 @@ extern const struct lpddr2_min_tck *of_get_min_tck(struct device_node *np,
 extern const struct lpddr2_timings
 	*of_get_ddr_timings(struct device_node *np_ddr, struct device *dev,
 	u32 device_type, u32 *nr_frequencies);
+extern const struct lpddr3_min_tck
+	*of_lpddr3_get_min_tck(struct device_node *np, struct device *dev);
+extern const struct lpddr3_timings
+	*of_lpddr3_get_ddr_timings(struct device_node *np_ddr,
+	struct device *dev, u32 device_type, u32 *nr_frequencies);
 #else
 static inline const struct lpddr2_min_tck
 	*of_get_min_tck(struct device_node *np, struct device *dev)
@@ -31,6 +36,19 @@ static inline const struct lpddr2_timings
 {
 	return NULL;
 }
-#endif /* CONFIG_OF && CONFIG_DDR */
+
+static inline const struct lpddr3_min_tck
+	*of_lpddr3_get_min_tck(struct device_node *np, struct device *dev)
+{
+	return NULL;
+}
+
+static inline const struct lpddr3_timings
+	*of_lpddr3_get_ddr_timings(struct device_node *np_ddr,
+	struct device *dev, u32 device_type, u32 *nr_frequencies)
+{
+	return NULL;
+}
+#endif
 
 #endif /* __LINUX_MEMORY_OF_REG_ */
diff --git a/include/memory/jedec_ddr.h b/include/memory/jedec_ddr.h
index ddad0f8..3601825 100644
--- a/include/memory/jedec_ddr.h
+++ b/include/memory/jedec_ddr.h
@@ -32,6 +32,7 @@
 #define DDR_TYPE_LPDDR2_S4	3
 #define DDR_TYPE_LPDDR2_S2	4
 #define DDR_TYPE_LPDDR2_NVM	5
+#define DDR_TYPE_LPDDR3		6
 
 /* DDR IO width */
 #define DDR_IO_WIDTH_4		1
@@ -172,4 +173,65 @@ extern const struct lpddr2_timings
 	lpddr2_jedec_timings[NUM_DDR_TIMING_TABLE_ENTRIES];
 extern const struct lpddr2_min_tck lpddr2_jedec_min_tck;
 
+
+/*
+ * Structure for timings for LPDDR3 based on LPDDR2 plus additional fields.
+ * All parameters are in pico seconds(ps) unless explicitly indicated
+ * with a suffix like tRAS_max_ns below
+ */
+struct lpddr3_timings {
+	u32 max_freq;
+	u32 min_freq;
+	u32 tRFC;
+	u32 tRRD;
+	u32 tRPab;
+	u32 tRPpb;
+	u32 tRCD;
+	u32 tRC;
+	u32 tRAS;
+	u32 tWTR;
+	u32 tWR;
+	u32 tRTP;
+	u32 tW2W_C2C;
+	u32 tR2R_C2C;
+	u32 tWL;
+	u32 tDQSCK;
+	u32 tRL;
+	u32 tFAW;
+	u32 tXSR;
+	u32 tXP;
+	u32 tCKE;
+	u32 tCKESR;
+	u32 tMRD;
+};
+
+/*
+ * Min value for some parameters in terms of number of tCK cycles(nCK)
+ * Please set to zero parameters that are not valid for a given memory
+ * type
+ */
+struct lpddr3_min_tck {
+	u32 tRFC;
+	u32 tRRD;
+	u32 tRPab;
+	u32 tRPpb;
+	u32 tRCD;
+	u32 tRC;
+	u32 tRAS;
+	u32 tWTR;
+	u32 tWR;
+	u32 tRTP;
+	u32 tW2W_C2C;
+	u32 tR2R_C2C;
+	u32 tWL;
+	u32 tDQSCK;
+	u32 tRL;
+	u32 tFAW;
+	u32 tXSR;
+	u32 tXP;
+	u32 tCKE;
+	u32 tCKESR;
+	u32 tMRD;
+};
+
 #endif /* __LINUX_JEDEC_DDR_H */
-- 
2.7.4

[PATCH v6 06/10] dt-bindings: memory-controllers: add Exynos5422 DMC device description

[Lukasz Luba]

The patch adds description for DT binding for a new Exynos5422 Dynamic
Memory Controller device.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 .../bindings/memory-controllers/exynos5422-dmc.txt | 73 ++++++++++++++++++++++
 1 file changed, 73 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt

diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
new file mode 100644
index 0000000..133b3cc
--- /dev/null
+++ b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
@@ -0,0 +1,73 @@
+* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device
+
+The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM
+memory chips are connected. The driver is to monitor the controller in runtime
+and switch frequency and voltage. To monitor the usage of the controller in
+runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
+is able to measure the current load of the memory.
+When 'userspace' governor is used for the driver, an application is able to
+switch the DMC and memory frequency.
+
+Required properties for DMC device for Exynos5422:
+- compatible: Should be "samsung,exynos5422-bus".
+- clock-names : the name of clock used by the bus, "bus".
+- clocks : phandles for clock specified in "clock-names" property.
+- devfreq-events : phandles for PPMU devices connected to this DMC.
+- vdd-supply : phandle for voltage regulator which is connected.
+- reg : registers of two CDREX controllers, chip information, clocks subsystem.
+- operating-points-v2 : phandle for OPPs described in v2 definition.
+- device-handle : phandle of the connected DRAM memory device. For more
+	information please refer to Documentation
+- devfreq-events : phandles of the PPMU events used by the controller.
+
+Example:
+
+	ppmu_dmc0_0: ppmu@10d00000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x10d00000 0x2000>;
+		clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
+		clock-names = "ppmu";
+		status = "okay";
+		events {
+			ppmu_event_dmc0_0: ppmu-event3-dmc0_0 {
+				event-name = "ppmu-event3-dmc0_0";
+			};
+		};
+	};
+
+	dmc: memory-controller@10c20000 {
+		compatible = "samsung,exynos5422-dmc";
+		reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
+			<0x10000000 0x1000>, <0x10030000 0x1000>;
+		clocks = 	<&clock CLK_FOUT_SPLL>,
+				<&clock CLK_MOUT_SCLK_SPLL>,
+				<&clock CLK_FF_DOUT_SPLL2>,
+				<&clock CLK_FOUT_BPLL>,
+				<&clock CLK_MOUT_BPLL>,
+				<&clock CLK_SCLK_BPLL>,
+				<&clock CLK_MOUT_MX_MSPLL_CCORE>,
+				<&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
+				<&clock CLK_MOUT_MCLK_CDREX>,
+				<&clock CLK_DOUT_CLK2X_PHY0>,
+				<&clock CLK_CLKM_PHY0>,
+				<&clock CLK_CLKM_PHY1>;
+		clock-names =	"fout_spll",
+				"mout_sclk_spll",
+				"ff_dout_spll2",
+				"fout_bpll",
+				"mout_bpll",
+				"sclk_bpll",
+				"mout_mx_mspll_ccore",
+				"mout_mx_mspll_ccore_phy",
+				"mout_mclk_cdrex",
+				"dout_clk2x_phy0",
+				"clkm_phy0",
+			        "clkm_phy1";
+		status = "okay";
+		operating-points-v2 = <&dmc_opp_table>;
+		devfreq-events = <&ppmu_event3_dmc0_0>,	<&ppmu_event3_dmc0_1>,
+				<&ppmu_event3_dmc1_0>, <&ppmu_event3_dmc1_1>;
+		operating-points-v2 = <&dmc_opp_table>;
+		device-handle = <&samsung_K3QF2F20DB>;
+		vdd-supply = <&buck1_reg>;
+	};
-- 
2.7.4

Re: [PATCH v6 06/10] dt-bindings: memory-controllers: add Exynos5422 DMC device description

[Rob Herring]

On Fri, Apr 19, 2019 at 04:19:24PM +0200, Lukasz Luba wrote:
> The patch adds description for DT binding for a new Exynos5422 Dynamic
> Memory Controller device.
> 
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  .../bindings/memory-controllers/exynos5422-dmc.txt | 73 ++++++++++++++++++++++
>  1 file changed, 73 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
> 
> diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
> new file mode 100644
> index 0000000..133b3cc
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
> @@ -0,0 +1,73 @@
> +* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device
> +
> +The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM
> +memory chips are connected. The driver is to monitor the controller in runtime
> +and switch frequency and voltage. To monitor the usage of the controller in
> +runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
> +is able to measure the current load of the memory.
> +When 'userspace' governor is used for the driver, an application is able to
> +switch the DMC and memory frequency.
> +
> +Required properties for DMC device for Exynos5422:
> +- compatible: Should be "samsung,exynos5422-bus".
> +- clock-names : the name of clock used by the bus, "bus".
> +- clocks : phandles for clock specified in "clock-names" property.
> +- devfreq-events : phandles for PPMU devices connected to this DMC.
> +- vdd-supply : phandle for voltage regulator which is connected.
> +- reg : registers of two CDREX controllers, chip information, clocks subsystem.
> +- operating-points-v2 : phandle for OPPs described in v2 definition.
> +- device-handle : phandle of the connected DRAM memory device. For more
> +	information please refer to Documentation

The memory node(s) should be a child of the memory controller IMO.

> +- devfreq-events : phandles of the PPMU events used by the controller.
> +
> +Example:
> +
> +	ppmu_dmc0_0: ppmu@10d00000 {
> +		compatible = "samsung,exynos-ppmu";
> +		reg = <0x10d00000 0x2000>;
> +		clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
> +		clock-names = "ppmu";
> +		status = "okay";

Don't show 'status' in examples.

> +		events {
> +			ppmu_event_dmc0_0: ppmu-event3-dmc0_0 {
> +				event-name = "ppmu-event3-dmc0_0";
> +			};
> +		};
> +	};
> +
> +	dmc: memory-controller@10c20000 {
> +		compatible = "samsung,exynos5422-dmc";
> +		reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
> +			<0x10000000 0x1000>, <0x10030000 0x1000>;
> +		clocks = 	<&clock CLK_FOUT_SPLL>,
> +				<&clock CLK_MOUT_SCLK_SPLL>,
> +				<&clock CLK_FF_DOUT_SPLL2>,
> +				<&clock CLK_FOUT_BPLL>,
> +				<&clock CLK_MOUT_BPLL>,
> +				<&clock CLK_SCLK_BPLL>,
> +				<&clock CLK_MOUT_MX_MSPLL_CCORE>,
> +				<&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
> +				<&clock CLK_MOUT_MCLK_CDREX>,
> +				<&clock CLK_DOUT_CLK2X_PHY0>,
> +				<&clock CLK_CLKM_PHY0>,
> +				<&clock CLK_CLKM_PHY1>;
> +		clock-names =	"fout_spll",
> +				"mout_sclk_spll",
> +				"ff_dout_spll2",
> +				"fout_bpll",
> +				"mout_bpll",
> +				"sclk_bpll",
> +				"mout_mx_mspll_ccore",
> +				"mout_mx_mspll_ccore_phy",
> +				"mout_mclk_cdrex",
> +				"dout_clk2x_phy0",
> +				"clkm_phy0",
> +			        "clkm_phy1";
> +		status = "okay";
> +		operating-points-v2 = <&dmc_opp_table>;
> +		devfreq-events = <&ppmu_event3_dmc0_0>,	<&ppmu_event3_dmc0_1>,
> +				<&ppmu_event3_dmc1_0>, <&ppmu_event3_dmc1_1>;
> +		operating-points-v2 = <&dmc_opp_table>;
> +		device-handle = <&samsung_K3QF2F20DB>;
> +		vdd-supply = <&buck1_reg>;
> +	};
> -- 
> 2.7.4
> 

Re: [PATCH v6 06/10] dt-bindings: memory-controllers: add Exynos5422 DMC device description

[Lukasz Luba]

Hi Rob,

On 4/25/19 9:57 PM, Rob Herring wrote:
> On Fri, Apr 19, 2019 at 04:19:24PM +0200, Lukasz Luba wrote:
>> The patch adds description for DT binding for a new Exynos5422 Dynamic
>> Memory Controller device.
>>
>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>> ---
>>   .../bindings/memory-controllers/exynos5422-dmc.txt | 73 ++++++++++++++++++++++
>>   1 file changed, 73 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>>
>> diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>> new file mode 100644
>> index 0000000..133b3cc
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>> @@ -0,0 +1,73 @@
>> +* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device
>> +
>> +The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM
>> +memory chips are connected. The driver is to monitor the controller in runtime
>> +and switch frequency and voltage. To monitor the usage of the controller in
>> +runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
>> +is able to measure the current load of the memory.
>> +When 'userspace' governor is used for the driver, an application is able to
>> +switch the DMC and memory frequency.
>> +
>> +Required properties for DMC device for Exynos5422:
>> +- compatible: Should be "samsung,exynos5422-bus".
>> +- clock-names : the name of clock used by the bus, "bus".
>> +- clocks : phandles for clock specified in "clock-names" property.
>> +- devfreq-events : phandles for PPMU devices connected to this DMC.
>> +- vdd-supply : phandle for voltage regulator which is connected.
>> +- reg : registers of two CDREX controllers, chip information, clocks subsystem.
>> +- operating-points-v2 : phandle for OPPs described in v2 definition.
>> +- device-handle : phandle of the connected DRAM memory device. For more
>> +	information please refer to Documentation
> 
> The memory node(s) should be a child of the memory controller IMO.
I have followed the TI code for LPDDR2. They use 'device-handle'
probably because the memory controller can be moved into the common
.dtsi and taken by reference in .dts in a proper board file.
The board .dts files might specify different DRAM chips and timings.
In Exynos case we will also have such situation: one memory controller
and a few different DRAM chips.

> 
>> +- devfreq-events : phandles of the PPMU events used by the controller.
>> +
>> +Example:
>> +
>> +	ppmu_dmc0_0: ppmu@10d00000 {
>> +		compatible = "samsung,exynos-ppmu";
>> +		reg = <0x10d00000 0x2000>;
>> +		clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
>> +		clock-names = "ppmu";
>> +		status = "okay";
> 
> Don't show 'status' in examples.
Thank you, I accidentally copied it from dt file.

Regards,
Lukasz
> 
>> +		events {
>> +			ppmu_event_dmc0_0: ppmu-event3-dmc0_0 {
>> +				event-name = "ppmu-event3-dmc0_0";
>> +			};
>> +		};
>> +	};
>> +
>> +	dmc: memory-controller@10c20000 {
>> +		compatible = "samsung,exynos5422-dmc";
>> +		reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
>> +			<0x10000000 0x1000>, <0x10030000 0x1000>;
>> +		clocks = 	<&clock CLK_FOUT_SPLL>,
>> +				<&clock CLK_MOUT_SCLK_SPLL>,
>> +				<&clock CLK_FF_DOUT_SPLL2>,
>> +				<&clock CLK_FOUT_BPLL>,
>> +				<&clock CLK_MOUT_BPLL>,
>> +				<&clock CLK_SCLK_BPLL>,
>> +				<&clock CLK_MOUT_MX_MSPLL_CCORE>,
>> +				<&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
>> +				<&clock CLK_MOUT_MCLK_CDREX>,
>> +				<&clock CLK_DOUT_CLK2X_PHY0>,
>> +				<&clock CLK_CLKM_PHY0>,
>> +				<&clock CLK_CLKM_PHY1>;
>> +		clock-names =	"fout_spll",
>> +				"mout_sclk_spll",
>> +				"ff_dout_spll2",
>> +				"fout_bpll",
>> +				"mout_bpll",
>> +				"sclk_bpll",
>> +				"mout_mx_mspll_ccore",
>> +				"mout_mx_mspll_ccore_phy",
>> +				"mout_mclk_cdrex",
>> +				"dout_clk2x_phy0",
>> +				"clkm_phy0",
>> +			        "clkm_phy1";
>> +		status = "okay";
>> +		operating-points-v2 = <&dmc_opp_table>;
>> +		devfreq-events = <&ppmu_event3_dmc0_0>,	<&ppmu_event3_dmc0_1>,
>> +				<&ppmu_event3_dmc1_0>, <&ppmu_event3_dmc1_1>;
>> +		operating-points-v2 = <&dmc_opp_table>;
>> +		device-handle = <&samsung_K3QF2F20DB>;
>> +		vdd-supply = <&buck1_reg>;
>> +	};
>> -- 
>> 2.7.4
>>
> 
> 

Re: [PATCH v6 06/10] dt-bindings: memory-controllers: add Exynos5422 DMC device description

[Rob Herring]

On Mon, Apr 29, 2019 at 7:14 AM Lukasz Luba <l.luba@partner.samsung.com> wrote:
>
> Hi Rob,
>
> On 4/25/19 9:57 PM, Rob Herring wrote:
> > On Fri, Apr 19, 2019 at 04:19:24PM +0200, Lukasz Luba wrote:
> >> The patch adds description for DT binding for a new Exynos5422 Dynamic
> >> Memory Controller device.
> >>
> >> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> >> ---
> >>   .../bindings/memory-controllers/exynos5422-dmc.txt | 73 ++++++++++++++++++++++
> >>   1 file changed, 73 insertions(+)
> >>   create mode 100644 Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
> >>
> >> diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
> >> new file mode 100644
> >> index 0000000..133b3cc
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
> >> @@ -0,0 +1,73 @@
> >> +* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device
> >> +
> >> +The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM
> >> +memory chips are connected. The driver is to monitor the controller in runtime
> >> +and switch frequency and voltage. To monitor the usage of the controller in
> >> +runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
> >> +is able to measure the current load of the memory.
> >> +When 'userspace' governor is used for the driver, an application is able to
> >> +switch the DMC and memory frequency.
> >> +
> >> +Required properties for DMC device for Exynos5422:
> >> +- compatible: Should be "samsung,exynos5422-bus".
> >> +- clock-names : the name of clock used by the bus, "bus".
> >> +- clocks : phandles for clock specified in "clock-names" property.
> >> +- devfreq-events : phandles for PPMU devices connected to this DMC.
> >> +- vdd-supply : phandle for voltage regulator which is connected.
> >> +- reg : registers of two CDREX controllers, chip information, clocks subsystem.
> >> +- operating-points-v2 : phandle for OPPs described in v2 definition.
> >> +- device-handle : phandle of the connected DRAM memory device. For more
> >> +    information please refer to Documentation
> >
> > The memory node(s) should be a child of the memory controller IMO.
> I have followed the TI code for LPDDR2. They use 'device-handle'
> probably because the memory controller can be moved into the common
> .dtsi and taken by reference in .dts in a proper board file.

You'd still have to have the ctrlr node in the board file to add the
'device-handle' property.

> The board .dts files might specify different DRAM chips and timings.
> In Exynos case we will also have such situation: one memory controller
> and a few different DRAM chips.

You mean as in the case where there are multiple options and one chip
gets populated on the board? So 'device-handle' is selecting which
chip to use.

You can actually do both here. Keep 'device-handle' to select which
DRAM chip and have the chips as child nodes. But if you really don't
want to have them as child nodes, that's fine.

Rob

Re: [PATCH v6 06/10] dt-bindings: memory-controllers: add Exynos5422 DMC device description

[Lukasz Luba]

On 4/29/19 6:43 PM, Rob Herring wrote:
> On Mon, Apr 29, 2019 at 7:14 AM Lukasz Luba <l.luba@partner.samsung.com> wrote:
>>
>> Hi Rob,
>>
>> On 4/25/19 9:57 PM, Rob Herring wrote:
>>> On Fri, Apr 19, 2019 at 04:19:24PM +0200, Lukasz Luba wrote:
>>>> The patch adds description for DT binding for a new Exynos5422 Dynamic
>>>> Memory Controller device.
>>>>
>>>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>>>> ---
>>>>    .../bindings/memory-controllers/exynos5422-dmc.txt | 73 ++++++++++++++++++++++
>>>>    1 file changed, 73 insertions(+)
>>>>    create mode 100644 Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>>>> new file mode 100644
>>>> index 0000000..133b3cc
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>>>> @@ -0,0 +1,73 @@
>>>> +* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device
>>>> +
>>>> +The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM
>>>> +memory chips are connected. The driver is to monitor the controller in runtime
>>>> +and switch frequency and voltage. To monitor the usage of the controller in
>>>> +runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
>>>> +is able to measure the current load of the memory.
>>>> +When 'userspace' governor is used for the driver, an application is able to
>>>> +switch the DMC and memory frequency.
>>>> +
>>>> +Required properties for DMC device for Exynos5422:
>>>> +- compatible: Should be "samsung,exynos5422-bus".
>>>> +- clock-names : the name of clock used by the bus, "bus".
>>>> +- clocks : phandles for clock specified in "clock-names" property.
>>>> +- devfreq-events : phandles for PPMU devices connected to this DMC.
>>>> +- vdd-supply : phandle for voltage regulator which is connected.
>>>> +- reg : registers of two CDREX controllers, chip information, clocks subsystem.
>>>> +- operating-points-v2 : phandle for OPPs described in v2 definition.
>>>> +- device-handle : phandle of the connected DRAM memory device. For more
>>>> +    information please refer to Documentation
>>>
>>> The memory node(s) should be a child of the memory controller IMO.
>> I have followed the TI code for LPDDR2. They use 'device-handle'
>> probably because the memory controller can be moved into the common
>> .dtsi and taken by reference in .dts in a proper board file.
> 
> You'd still have to have the ctrlr node in the board file to add the
> 'device-handle' property.
> 
>> The board .dts files might specify different DRAM chips and timings.
>> In Exynos case we will also have such situation: one memory controller
>> and a few different DRAM chips.
> 
> You mean as in the case where there are multiple options and one chip
> gets populated on the board? So 'device-handle' is selecting which
> chip to use.
Yes. The 'device-handle' will point to different memories depending on
the board/SoCs. There are boards with Exynos 5420, 5422, 5800 which are
'almost' the same, but with different memories glued on top (the PoP
LPDDR3).
> 
> You can actually do both here. Keep 'device-handle' to select which
> DRAM chip and have the chips as child nodes. But if you really don't
> want to have them as child nodes, that's fine.
For now, I would like to keep it like this (if Krzysztof also agrees
with the implementation).

Regards,
Lukasz
> 
> Rob
> 
> 

Re: [PATCH v6 06/10] dt-bindings: memory-controllers: add Exynos5422 DMC device description

[Chanwoo Choi]

On 19. 4. 19. 오후 11:19, Lukasz Luba wrote:
> The patch adds description for DT binding for a new Exynos5422 Dynamic
> Memory Controller device.
> 
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  .../bindings/memory-controllers/exynos5422-dmc.txt | 73 ++++++++++++++++++++++
>  1 file changed, 73 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
> 
> diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
> new file mode 100644
> index 0000000..133b3cc
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
> @@ -0,0 +1,73 @@
> +* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device
> +
> +The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM
> +memory chips are connected. The driver is to monitor the controller in runtime
> +and switch frequency and voltage. To monitor the usage of the controller in
> +runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
> +is able to measure the current load of the memory.
> +When 'userspace' governor is used for the driver, an application is able to
> +switch the DMC and memory frequency.
> +
> +Required properties for DMC device for Exynos5422:
> +- compatible: Should be "samsung,exynos5422-bus".

As I already mentioned on many times, it is not fixed.
You have to fix it as following:
- exynos5422-bus -> exynos5422-dmc

> +- clock-names : the name of clock used by the bus, "bus".

The below examples doesn't contain the 'bus' clock name.

> +- clocks : phandles for clock specified in "clock-names" property.
> +- devfreq-events : phandles for PPMU devices connected to this DMC.
> +- vdd-supply : phandle for voltage regulator which is connected.
> +- reg : registers of two CDREX controllers, chip information, clocks subsystem.
> +- operating-points-v2 : phandle for OPPs described in v2 definition.
> +- device-handle : phandle of the connected DRAM memory device. For more
> +	information please refer to Documentation
> +- devfreq-events : phandles of the PPMU events used by the controller.
> +
> +Example:
> +
> +	ppmu_dmc0_0: ppmu@10d00000 {
> +		compatible = "samsung,exynos-ppmu";
> +		reg = <0x10d00000 0x2000>;
> +		clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
> +		clock-names = "ppmu";
> +		status = "okay";
> +		events {
> +			ppmu_event_dmc0_0: ppmu-event3-dmc0_0 {
> +				event-name = "ppmu-event3-dmc0_0";
> +			};
> +		};
> +	};
> +
> +	dmc: memory-controller@10c20000 {
> +		compatible = "samsung,exynos5422-dmc";
> +		reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
> +			<0x10000000 0x1000>, <0x10030000 0x1000>;
> +		clocks = 	<&clock CLK_FOUT_SPLL>,
> +				<&clock CLK_MOUT_SCLK_SPLL>,
> +				<&clock CLK_FF_DOUT_SPLL2>,
> +				<&clock CLK_FOUT_BPLL>,
> +				<&clock CLK_MOUT_BPLL>,
> +				<&clock CLK_SCLK_BPLL>,
> +				<&clock CLK_MOUT_MX_MSPLL_CCORE>,
> +				<&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
> +				<&clock CLK_MOUT_MCLK_CDREX>,
> +				<&clock CLK_DOUT_CLK2X_PHY0>,
> +				<&clock CLK_CLKM_PHY0>,
> +				<&clock CLK_CLKM_PHY1>;
> +		clock-names =	"fout_spll",
> +				"mout_sclk_spll",
> +				"ff_dout_spll2",
> +				"fout_bpll",
> +				"mout_bpll",
> +				"sclk_bpll",
> +				"mout_mx_mspll_ccore",
> +				"mout_mx_mspll_ccore_phy",
> +				"mout_mclk_cdrex",
> +				"dout_clk2x_phy0",
> +				"clkm_phy0",
> +			        "clkm_phy1";
> +		status = "okay";
> +		operating-points-v2 = <&dmc_opp_table>;
> +		devfreq-events = <&ppmu_event3_dmc0_0>,	<&ppmu_event3_dmc0_1>,
> +				<&ppmu_event3_dmc1_0>, <&ppmu_event3_dmc1_1>;
> +		operating-points-v2 = <&dmc_opp_table>;
> +		device-handle = <&samsung_K3QF2F20DB>;
> +		vdd-supply = <&buck1_reg>;
> +	};
> 


-- 
Best Regards,
Chanwoo Choi
Samsung Electronics

Re: [PATCH v6 06/10] dt-bindings: memory-controllers: add Exynos5422 DMC device description

[Lukasz Luba]

Hi Chanwoo,

On 4/30/19 6:46 AM, Chanwoo Choi wrote:
> On 19. 4. 19. 오후 11:19, Lukasz Luba wrote:
>> The patch adds description for DT binding for a new Exynos5422 Dynamic
>> Memory Controller device.
>>
>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>> ---
>>   .../bindings/memory-controllers/exynos5422-dmc.txt | 73 ++++++++++++++++++++++
>>   1 file changed, 73 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>>
>> diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>> new file mode 100644
>> index 0000000..133b3cc
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>> @@ -0,0 +1,73 @@
>> +* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device
>> +
>> +The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM
>> +memory chips are connected. The driver is to monitor the controller in runtime
>> +and switch frequency and voltage. To monitor the usage of the controller in
>> +runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
>> +is able to measure the current load of the memory.
>> +When 'userspace' governor is used for the driver, an application is able to
>> +switch the DMC and memory frequency.
>> +
>> +Required properties for DMC device for Exynos5422:
>> +- compatible: Should be "samsung,exynos5422-bus".
> 
> As I already mentioned on many times, it is not fixed.
> You have to fix it as following:
> - exynos5422-bus -> exynos5422-dmc
I don't know how I missed it on my list. My apologies.
> 
>> +- clock-names : the name of clock used by the bus, "bus".
> 
> The below examples doesn't contain the 'bus' clock name.
True. Thank you for pointing this out. I will it.

Regards,
Lukasz
> 
>> +- clocks : phandles for clock specified in "clock-names" property.
>> +- devfreq-events : phandles for PPMU devices connected to this DMC.
>> +- vdd-supply : phandle for voltage regulator which is connected.
>> +- reg : registers of two CDREX controllers, chip information, clocks subsystem.
>> +- operating-points-v2 : phandle for OPPs described in v2 definition.
>> +- device-handle : phandle of the connected DRAM memory device. For more
>> +	information please refer to Documentation
>> +- devfreq-events : phandles of the PPMU events used by the controller.
>> +
>> +Example:
>> +
>> +	ppmu_dmc0_0: ppmu@10d00000 {
>> +		compatible = "samsung,exynos-ppmu";
>> +		reg = <0x10d00000 0x2000>;
>> +		clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
>> +		clock-names = "ppmu";
>> +		status = "okay";
>> +		events {
>> +			ppmu_event_dmc0_0: ppmu-event3-dmc0_0 {
>> +				event-name = "ppmu-event3-dmc0_0";
>> +			};
>> +		};
>> +	};
>> +
>> +	dmc: memory-controller@10c20000 {
>> +		compatible = "samsung,exynos5422-dmc";
>> +		reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
>> +			<0x10000000 0x1000>, <0x10030000 0x1000>;
>> +		clocks = 	<&clock CLK_FOUT_SPLL>,
>> +				<&clock CLK_MOUT_SCLK_SPLL>,
>> +				<&clock CLK_FF_DOUT_SPLL2>,
>> +				<&clock CLK_FOUT_BPLL>,
>> +				<&clock CLK_MOUT_BPLL>,
>> +				<&clock CLK_SCLK_BPLL>,
>> +				<&clock CLK_MOUT_MX_MSPLL_CCORE>,
>> +				<&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
>> +				<&clock CLK_MOUT_MCLK_CDREX>,
>> +				<&clock CLK_DOUT_CLK2X_PHY0>,
>> +				<&clock CLK_CLKM_PHY0>,
>> +				<&clock CLK_CLKM_PHY1>;
>> +		clock-names =	"fout_spll",
>> +				"mout_sclk_spll",
>> +				"ff_dout_spll2",
>> +				"fout_bpll",
>> +				"mout_bpll",
>> +				"sclk_bpll",
>> +				"mout_mx_mspll_ccore",
>> +				"mout_mx_mspll_ccore_phy",
>> +				"mout_mclk_cdrex",
>> +				"dout_clk2x_phy0",
>> +				"clkm_phy0",
>> +			        "clkm_phy1";
>> +		status = "okay";
>> +		operating-points-v2 = <&dmc_opp_table>;
>> +		devfreq-events = <&ppmu_event3_dmc0_0>,	<&ppmu_event3_dmc0_1>,
>> +				<&ppmu_event3_dmc1_0>, <&ppmu_event3_dmc1_1>;
>> +		operating-points-v2 = <&dmc_opp_table>;
>> +		device-handle = <&samsung_K3QF2F20DB>;
>> +		vdd-supply = <&buck1_reg>;
>> +	};
>>
> 
> 

Re: [PATCH v6 06/10] dt-bindings: memory-controllers: add Exynos5422 DMC device description

[Chanwoo Choi]

Hi Lukasz,

On 19. 5. 1. 오전 5:30, Lukasz Luba wrote:
> Hi Chanwoo,
> 
> On 4/30/19 6:46 AM, Chanwoo Choi wrote:
>> On 19. 4. 19. 오후 11:19, Lukasz Luba wrote:
>>> The patch adds description for DT binding for a new Exynos5422 Dynamic
>>> Memory Controller device.
>>>
>>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>>> ---
>>>   .../bindings/memory-controllers/exynos5422-dmc.txt | 73 ++++++++++++++++++++++
>>>   1 file changed, 73 insertions(+)
>>>   create mode 100644 Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>>> new file mode 100644
>>> index 0000000..133b3cc
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>>> @@ -0,0 +1,73 @@
>>> +* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device
>>> +
>>> +The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM
>>> +memory chips are connected. The driver is to monitor the controller in runtime
>>> +and switch frequency and voltage. To monitor the usage of the controller in
>>> +runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
>>> +is able to measure the current load of the memory.
>>> +When 'userspace' governor is used for the driver, an application is able to
>>> +switch the DMC and memory frequency.
>>> +
>>> +Required properties for DMC device for Exynos5422:
>>> +- compatible: Should be "samsung,exynos5422-bus".
>>
>> As I already mentioned on many times, it is not fixed.
>> You have to fix it as following:
>> - exynos5422-bus -> exynos5422-dmc
> I don't know how I missed it on my list. My apologies.
>>
>>> +- clock-names : the name of clock used by the bus, "bus".
>>
>> The below examples doesn't contain the 'bus' clock name.
> True. Thank you for pointing this out. I will it.
> 
> Regards,
> Lukasz
>>
>>> +- clocks : phandles for clock specified in "clock-names" property.
>>> +- devfreq-events : phandles for PPMU devices connected to this DMC.
>>> +- vdd-supply : phandle for voltage regulator which is connected.
>>> +- reg : registers of two CDREX controllers, chip information, clocks subsystem.
>>> +- operating-points-v2 : phandle for OPPs described in v2 definition.
>>> +- device-handle : phandle of the connected DRAM memory device. For more
>>> +	information please refer to Documentation
>>> +- devfreq-events : phandles of the PPMU events used by the controller.
>>> +
>>> +Example:
>>> +
>>> +	ppmu_dmc0_0: ppmu@10d00000 {
>>> +		compatible = "samsung,exynos-ppmu";
>>> +		reg = <0x10d00000 0x2000>;
>>> +		clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
>>> +		clock-names = "ppmu";
>>> +		status = "okay";
>>> +		events {
>>> +			ppmu_event_dmc0_0: ppmu-event3-dmc0_0 {
>>> +				event-name = "ppmu-event3-dmc0_0";
>>> +			};
>>> +		};
>>> +	};
>>> +
>>> +	dmc: memory-controller@10c20000 {
>>> +		compatible = "samsung,exynos5422-dmc";
>>> +		reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
>>> +			<0x10000000 0x1000>, <0x10030000 0x1000>;

As I discussed about the register region of clock subsystem
with Sylwester on patch[1], I expected that you used the regmap
interface to control the register region of clock subsystem.

But, this dt-binding documents doesn't include any information
about regmap interface.

[1] https://lkml.org/lkml/2019/3/6/878

>>> +		clocks = 	<&clock CLK_FOUT_SPLL>,
>>> +				<&clock CLK_MOUT_SCLK_SPLL>,
>>> +				<&clock CLK_FF_DOUT_SPLL2>,
>>> +				<&clock CLK_FOUT_BPLL>,
>>> +				<&clock CLK_MOUT_BPLL>,
>>> +				<&clock CLK_SCLK_BPLL>,
>>> +				<&clock CLK_MOUT_MX_MSPLL_CCORE>,
>>> +				<&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
>>> +				<&clock CLK_MOUT_MCLK_CDREX>,
>>> +				<&clock CLK_DOUT_CLK2X_PHY0>,
>>> +				<&clock CLK_CLKM_PHY0>,
>>> +				<&clock CLK_CLKM_PHY1>;
>>> +		clock-names =	"fout_spll",
>>> +				"mout_sclk_spll",
>>> +				"ff_dout_spll2",
>>> +				"fout_bpll",
>>> +				"mout_bpll",
>>> +				"sclk_bpll",
>>> +				"mout_mx_mspll_ccore",
>>> +				"mout_mx_mspll_ccore_phy",
>>> +				"mout_mclk_cdrex",
>>> +				"dout_clk2x_phy0",
>>> +				"clkm_phy0",
>>> +			        "clkm_phy1";
>>> +		status = "okay";
>>> +		operating-points-v2 = <&dmc_opp_table>;
>>> +		devfreq-events = <&ppmu_event3_dmc0_0>,	<&ppmu_event3_dmc0_1>,
>>> +				<&ppmu_event3_dmc1_0>, <&ppmu_event3_dmc1_1>;
>>> +		operating-points-v2 = <&dmc_opp_table>;
>>> +		device-handle = <&samsung_K3QF2F20DB>;
>>> +		vdd-supply = <&buck1_reg>;
>>> +	};
>>>
>>
>>
> 
> 


-- 
Best Regards,
Chanwoo Choi
Samsung Electronics

Re: [PATCH v6 06/10] dt-bindings: memory-controllers: add Exynos5422 DMC device description

[Lukasz Luba]

Hi Chanwoo,

On 5/2/19 3:35 AM, Chanwoo Choi wrote:
> Hi Lukasz,
> 
> On 19. 5. 1. 오전 5:30, Lukasz Luba wrote:
>> Hi Chanwoo,
>>
>> On 4/30/19 6:46 AM, Chanwoo Choi wrote:
>>> On 19. 4. 19. 오후 11:19, Lukasz Luba wrote:
>>>> The patch adds description for DT binding for a new Exynos5422 Dynamic
>>>> Memory Controller device.
>>>>
>>>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>>>> ---
>>>>    .../bindings/memory-controllers/exynos5422-dmc.txt | 73 ++++++++++++++++++++++
>>>>    1 file changed, 73 insertions(+)
>>>>    create mode 100644 Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>>>> new file mode 100644
>>>> index 0000000..133b3cc
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>>>> @@ -0,0 +1,73 @@
>>>> +* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device
>>>> +
>>>> +The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM
>>>> +memory chips are connected. The driver is to monitor the controller in runtime
>>>> +and switch frequency and voltage. To monitor the usage of the controller in
>>>> +runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
>>>> +is able to measure the current load of the memory.
>>>> +When 'userspace' governor is used for the driver, an application is able to
>>>> +switch the DMC and memory frequency.
>>>> +
>>>> +Required properties for DMC device for Exynos5422:
>>>> +- compatible: Should be "samsung,exynos5422-bus".
>>>
>>> As I already mentioned on many times, it is not fixed.
>>> You have to fix it as following:
>>> - exynos5422-bus -> exynos5422-dmc
>> I don't know how I missed it on my list. My apologies.
>>>
>>>> +- clock-names : the name of clock used by the bus, "bus".
>>>
>>> The below examples doesn't contain the 'bus' clock name.
>> True. Thank you for pointing this out. I will it.
>>
>> Regards,
>> Lukasz
>>>
>>>> +- clocks : phandles for clock specified in "clock-names" property.
>>>> +- devfreq-events : phandles for PPMU devices connected to this DMC.
>>>> +- vdd-supply : phandle for voltage regulator which is connected.
>>>> +- reg : registers of two CDREX controllers, chip information, clocks subsystem.
>>>> +- operating-points-v2 : phandle for OPPs described in v2 definition.
>>>> +- device-handle : phandle of the connected DRAM memory device. For more
>>>> +	information please refer to Documentation
>>>> +- devfreq-events : phandles of the PPMU events used by the controller.
>>>> +
>>>> +Example:
>>>> +
>>>> +	ppmu_dmc0_0: ppmu@10d00000 {
>>>> +		compatible = "samsung,exynos-ppmu";
>>>> +		reg = <0x10d00000 0x2000>;
>>>> +		clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
>>>> +		clock-names = "ppmu";
>>>> +		status = "okay";
>>>> +		events {
>>>> +			ppmu_event_dmc0_0: ppmu-event3-dmc0_0 {
>>>> +				event-name = "ppmu-event3-dmc0_0";
>>>> +			};
>>>> +		};
>>>> +	};
>>>> +
>>>> +	dmc: memory-controller@10c20000 {
>>>> +		compatible = "samsung,exynos5422-dmc";
>>>> +		reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
>>>> +			<0x10000000 0x1000>, <0x10030000 0x1000>;
> 
> As I discussed about the register region of clock subsystem
> with Sylwester on patch[1], I expected that you used the regmap
> interface to control the register region of clock subsystem.
> 
> But, this dt-binding documents doesn't include any information
> about regmap interface.
Right. I will update the doc since the clock and chipid regs will use
phandle in DT and syscon_regmap in the driver code in the v7 patch set.

Regards,
Lukasz

> 
> [1] https://lkml.org/lkml/2019/3/6/878
> 
>>>> +		clocks = 	<&clock CLK_FOUT_SPLL>,
>>>> +				<&clock CLK_MOUT_SCLK_SPLL>,
>>>> +				<&clock CLK_FF_DOUT_SPLL2>,
>>>> +				<&clock CLK_FOUT_BPLL>,
>>>> +				<&clock CLK_MOUT_BPLL>,
>>>> +				<&clock CLK_SCLK_BPLL>,
>>>> +				<&clock CLK_MOUT_MX_MSPLL_CCORE>,
>>>> +				<&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
>>>> +				<&clock CLK_MOUT_MCLK_CDREX>,
>>>> +				<&clock CLK_DOUT_CLK2X_PHY0>,
>>>> +				<&clock CLK_CLKM_PHY0>,
>>>> +				<&clock CLK_CLKM_PHY1>;
>>>> +		clock-names =	"fout_spll",
>>>> +				"mout_sclk_spll",
>>>> +				"ff_dout_spll2",
>>>> +				"fout_bpll",
>>>> +				"mout_bpll",
>>>> +				"sclk_bpll",
>>>> +				"mout_mx_mspll_ccore",
>>>> +				"mout_mx_mspll_ccore_phy",
>>>> +				"mout_mclk_cdrex",
>>>> +				"dout_clk2x_phy0",
>>>> +				"clkm_phy0",
>>>> +			        "clkm_phy1";
>>>> +		status = "okay";
>>>> +		operating-points-v2 = <&dmc_opp_table>;
>>>> +		devfreq-events = <&ppmu_event3_dmc0_0>,	<&ppmu_event3_dmc0_1>,
>>>> +				<&ppmu_event3_dmc1_0>, <&ppmu_event3_dmc1_1>;
>>>> +		operating-points-v2 = <&dmc_opp_table>;
>>>> +		device-handle = <&samsung_K3QF2F20DB>;
>>>> +		vdd-supply = <&buck1_reg>;
>>>> +	};
>>>>
>>>
>>>
>>
>>
> 
> 

[PATCH v6 07/10] drivers: memory: add DMC driver for Exynos5422

[Lukasz Luba]

This patch adds driver for Exynos5422 Dynamic Memory Controller.
The driver provides support for dynamic frequency and voltage scaling for
DMC and DRAM. It supports changing timings of DRAM running with different
frequency. There is also an algorithm to calculate timigns based on
memory description provided in DT.
The patch also contains needed MAINTAINERS file update.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 MAINTAINERS                             |    8 +
 drivers/memory/samsung/Kconfig          |   17 +
 drivers/memory/samsung/Makefile         |    1 +
 drivers/memory/samsung/exynos5422-dmc.c | 1793 +++++++++++++++++++++++++++++++
 4 files changed, 1819 insertions(+)
 create mode 100644 drivers/memory/samsung/exynos5422-dmc.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 1ba4b9b..07e257d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3395,6 +3395,14 @@ S:	Maintained
 F:	drivers/devfreq/exynos-bus.c
 F:	Documentation/devicetree/bindings/devfreq/exynos-bus.txt
 
+DMC FREQUENCY DRIVER FOR SAMSUNG EXYNOS5422
+M:	Lukasz Luba <l.luba@partner.samsung.com>
+L:	linux-pm@vger.kernel.org
+L:	linux-samsung-soc@vger.kernel.org
+S:	Maintained
+F:	drivers/memory/samsung/exynos5422-dmc.c
+F:	Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
+
 BUSLOGIC SCSI DRIVER
 M:	Khalid Aziz <khalid@gonehiking.org>
 L:	linux-scsi@vger.kernel.org
diff --git a/drivers/memory/samsung/Kconfig b/drivers/memory/samsung/Kconfig
index 79ce7ea..202972b 100644
--- a/drivers/memory/samsung/Kconfig
+++ b/drivers/memory/samsung/Kconfig
@@ -5,6 +5,23 @@ config SAMSUNG_MC
 	  Support for the Memory Controller (MC) devices found on
 	  Samsung Exynos SoCs.
 
+config ARM_EXYNOS5422_DMC
+	tristate "ARM EXYNOS5422 Dynamic Memory Controller driver"
+	depends on ARCH_EXYNOS || COMPILE_TEST
+	select DDR
+	select PM_DEVFREQ
+	select DEVFREQ_GOV_SIMPLE_ONDEMAND
+	select DEVFREQ_GOV_USERSPACE
+	select PM_DEVFREQ_EVENT
+	select PM_OPP
+	help
+	  This adds driver for Exynos5422 DMC (Dynamic Memory Controller).
+	  The driver provides support for Dynamic Voltage and Frequency Scaling in
+	  DMC and DRAM. It also supports changing timings of DRAM running with
+	  different frequency. The timings are calculated based on DT memory
+	  information.
+
+
 if SAMSUNG_MC
 
 config EXYNOS_SROM
diff --git a/drivers/memory/samsung/Makefile b/drivers/memory/samsung/Makefile
index 00587be..4f6e438 100644
--- a/drivers/memory/samsung/Makefile
+++ b/drivers/memory/samsung/Makefile
@@ -1,2 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_ARM_EXYNOS5422_DMC)	+= exynos5422-dmc.o
 obj-$(CONFIG_EXYNOS_SROM)	+= exynos-srom.o
diff --git a/drivers/memory/samsung/exynos5422-dmc.c b/drivers/memory/samsung/exynos5422-dmc.c
new file mode 100644
index 0000000..fa4cd4c
--- /dev/null
+++ b/drivers/memory/samsung/exynos5422-dmc.c
@@ -0,0 +1,1793 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 Samsung Electronics Co., Ltd.
+ */
+
+#include <linux/clk.h>
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/devfreq.h>
+#include <linux/devfreq-event.h>
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pm_opp.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <memory/jedec_ddr.h>
+#include "../of_memory.h"
+
+#define EXYNOS5_DREXI_TIMINGAREF		(0x0030)
+#define EXYNOS5_DREXI_TIMINGROW0		(0x0034)
+#define EXYNOS5_DREXI_TIMINGDATA0		(0x0038)
+#define EXYNOS5_DREXI_TIMINGPOWER0		(0x003C)
+#define EXYNOS5_DREXI_TIMINGROW1		(0x00E4)
+#define EXYNOS5_DREXI_TIMINGDATA1		(0x00E8)
+#define EXYNOS5_DREXI_TIMINGPOWER1		(0x00EC)
+#define CDREX_PAUSE				(0x91c)
+#define CDREX_LPDDR3PHY_CON3			(0xa20)
+#define EXYNOS5_TIMING_SET_SWI                  (1UL << 28)
+#define USE_MX_MSPLL_TIMINGS			(1)
+#define USE_BPLL_TIMINGS			(0)
+
+#define EXYNOS5_AREF_NORMAL			(0x2e)
+
+#define IS_MEM_2GB(val) \
+	(						\
+	 (((val) & 0xf0) & 0x20) ? 1 :			\
+		(((val) & 0xf0) & 0x30) ? 1 : 0		\
+	)
+
+#define EXYNOS5_POP_OPTIONS(val)	(((val >> 4) & 0x3UL) << 4)
+#define EXYNOS5_DDR_TYPE(val)		(((val >> 14) & 0x1UL))
+
+#define EXYNOS5_CHIP_PROD_ID		(0)
+#define EXYNOS5_CHIP_PKG_ID		(4)
+
+#define PPMU_PMCNT_CONST_RATIO_MUL	15
+#define PPMU_PMCNT_CONST_RATIO_DIV	10
+
+#define AXI_BUS_WIDTH_BYTES (128 >> 3)
+
+/**
+ * enum dmc_slot_id - An enum with slots in DMC
+ */
+enum dmc_slot_id {
+	DMC0_0,
+	DMC0_1,
+	DMC1_0,
+	DMC1_1,
+	DMC_SLOTS_END
+};
+
+/**
+ * struct dmc_slot_info - Describes DMC's slot
+ *
+ * The structure holds DMC's slot name which is part of the device name
+ * provided in DT. Each slot has particular share of the DMC bandwidth.
+ * To abstract the model performance and values in performance counters,
+ * fields 'ratio_mul' and 'ratio_div' are used in calculation algorithm
+ * for each slot. Please check the corresponding function with the algorithm,
+ * to see how these variables are used.
+ */
+struct dmc_slot_info {
+	char *name;
+	int id;
+	int ratio_mul;
+	int ratio_div;
+};
+
+/**
+ * struct dmc_opp_table - Operating level desciption
+ *
+ * Covers frequency and voltage settings of the DMC operating mode.
+ */
+struct dmc_opp_table {
+	u32 freq_hz;
+	u32 volt_uv;
+};
+
+/**
+ * struct exynos5_dmc - main structure describing DMC device
+ *
+ * The main structure for the Dynamic Memory Controller which covers clocks,
+ * memory regions, HW information, parameters and current operating mode.
+ */
+struct exynos5_dmc {
+	struct device *dev;
+	struct devfreq *df;
+	struct devfreq_simple_ondemand_data gov_data;
+	void __iomem *base_drexi0;
+	void __iomem *base_drexi1;
+	void __iomem *chip_id;
+	struct regmap *clk_regmap;
+	struct mutex lock;
+	unsigned long curr_rate;
+	unsigned long curr_volt;
+	unsigned long bypass_rate;
+	struct dmc_opp_table *opp;
+	struct dmc_opp_table opp_bypass;
+	int opp_count;
+	u32 timings_arr_size;
+	u32 *timing_row;
+	u32 *timing_data;
+	u32 *timing_power;
+	const struct lpddr3_timings *timings;
+	const struct lpddr3_min_tck *min_tck;
+	u32 bypass_timing_row;
+	u32 bypass_timing_data;
+	u32 bypass_timing_power;
+	unsigned int prod_rev;
+	unsigned int pkg_rev;
+	unsigned int mem_info;
+	struct regulator *vdd_mif;
+	struct clk *fout_spll;
+	struct clk *fout_bpll;
+	struct clk *mout_spll;
+	struct clk *mout_bpll;
+	struct clk *mout_mclk_cdrex;
+	struct clk *dout_clk2x_phy0;
+	struct clk *mout_mx_mspll_ccore;
+	struct clk *mx_mspll_ccore_phy;
+	struct clk *mout_mx_mspll_ccore_phy;
+	struct devfreq_event_dev **counter;
+	int num_counters;
+	bool counters_enabled;
+#ifdef CONFIG_DEBUG_FS
+	struct dentry *dbg_root;
+#endif
+};
+
+#define TIMING_FIELD(t_name, t_bit_beg, t_bit_end) \
+	{ .name = t_name, .bit_beg = t_bit_beg, .bit_end = t_bit_end }
+
+#define TIMING_VAL(timing_array, id, t_val)			\
+({								\
+		u32 __val;				\
+		__val = t_val << timing_array[id].bit_beg;	\
+		__val;						\
+})
+
+#define TIMING_VAL2REG(timing, t_val)			\
+({								\
+		u32 __val;				\
+		__val = t_val << timing->bit_beg;	\
+		__val;						\
+})
+
+#define TIMING_REG2VAL(reg, timing)			\
+({								\
+		u32 __val;				\
+		reg <<= (31 - timing->bit_end);		\
+		reg >>= (31 - timing->bit_end);		\
+		__val = reg >> timing->bit_beg;	\
+		__val;						\
+})
+
+struct timing_reg {
+	char *name;
+	int bit_beg;
+	int bit_end;
+	unsigned int val;
+};
+
+static struct timing_reg timing_row[] = {
+	TIMING_FIELD("tRFC", 24, 31),
+	TIMING_FIELD("tRRD", 20, 23),
+	TIMING_FIELD("tRP", 16, 19),
+	TIMING_FIELD("tRCD", 12, 15),
+	TIMING_FIELD("tRC", 6, 11),
+	TIMING_FIELD("tRAS", 0, 5),
+};
+
+static struct timing_reg timing_data[] = {
+	TIMING_FIELD("tWTR", 28, 31),
+	TIMING_FIELD("tWR", 24, 27),
+	TIMING_FIELD("tRTP", 20, 23),
+	TIMING_FIELD("tW2W-C2C", 14, 14),
+	TIMING_FIELD("tR2R-C2C", 12, 12),
+	TIMING_FIELD("WL", 8, 11),
+	TIMING_FIELD("tDQSCK", 4, 7),
+	TIMING_FIELD("RL", 0, 3),
+};
+
+static struct timing_reg timing_power[] = {
+	TIMING_FIELD("tFAW", 26, 31),
+	TIMING_FIELD("tXSR", 16, 25),
+	TIMING_FIELD("tXP", 8, 15),
+	TIMING_FIELD("tCKE", 4, 7),
+	TIMING_FIELD("tMRD", 0, 3),
+};
+
+#define TIMING_COUNT (ARRAY_SIZE(timing_row) + ARRAY_SIZE(timing_data) + \
+		      ARRAY_SIZE(timing_power))
+
+/**
+ * exynos5_counters_fname() - Macro generating function for event devices
+ * @f:		function name suffix
+ *
+ * Macro which generates needed function for manipulation of event devices.
+ * It aims to avoid code duplication relaying on similar prefix and function
+ * parameters in the devfreq event device framework functions.
+ */
+#define exynos5_counters_fname(f)				\
+static int exynos5_counters_##f(struct exynos5_dmc *dmc)	\
+{								\
+	int i, ret;						\
+								\
+	for (i = 0; i < dmc->num_counters; i++) {		\
+		if (!dmc->counter[i])				\
+			continue;				\
+		ret = devfreq_event_##f(dmc->counter[i]);	\
+		if (ret < 0)					\
+			return ret;				\
+	}							\
+	return 0;						\
+}
+
+/* Declarations for the function generated by the macro above. */
+static int exynos5_counters_set_event(struct exynos5_dmc *dmc);
+static int exynos5_counters_enable_edev(struct exynos5_dmc *dmc);
+static int exynos5_counters_disable_edev(struct exynos5_dmc *dmc);
+
+/* Generate needed functions for managing event device. */
+exynos5_counters_fname(set_event);
+exynos5_counters_fname(enable_edev);
+exynos5_counters_fname(disable_edev);
+
+/* Event names to DMC channel and slot with proper data count type */
+static const char *event_name[] = {
+	/* Counters for DMC0 slot 0 */
+	"ppmu-event0-dmc0_0",
+	"DMC0_0-Read",
+	"ppmu-event1-dmc0_0",
+	"DMC0_0-Write",
+	"ppmu-event3-dmc0_0",
+	"DMC0_0-Read+Write",
+	/* Counters for DMC0 slot 1 */
+	"ppmu-event0-dmc0_1",
+	"DMC0_1-Read",
+	"ppmu-event1-dmc0_1",
+	"DMC0_1-Write",
+	"ppmu-event3-dmc0_1",
+	"DMC0_1-Read+Write",
+	/* Counters for DMC1 slot 0 */
+	"ppmu-event0-dmc1_0",
+	"DMC1_0-Read",
+	"ppmu-event1-dmc1_0",
+	"DMC1_0-Write",
+	"ppmu-event3-dmc1_0",
+	"DMC1_0-Read+Write",
+	/* Counters for DMC1 slot 0 */
+	"ppmu-event0-dmc1_1",
+	"DMC1_1-Read",
+	"ppmu-event1-dmc1_1",
+	"DMC1_1-Write",
+	"ppmu-event3-dmc1_1",
+	"DMC1_1-Read+Write",
+};
+
+/**
+ * find_target_freq_id() - Finds requested frequency in local DMC configuration
+ * @dmc:	device for which the information is checked
+ * @target_rate:	requested frequency in KHz
+ *
+ * Seeks in the local DMC driver structure for the requested frequency value
+ * and returns index or error value.
+ */
+static int find_target_freq_idx(struct exynos5_dmc *dmc,
+				unsigned long target_rate)
+{
+	int i;
+
+	for (i = dmc->opp_count - 1; i >= 0; i--)
+		if (dmc->opp[i].freq_hz <= target_rate)
+			return i;
+
+	return -EINVAL;
+}
+
+/**
+ * exynos5_dmc_chip_revision_settings() - Chooses proper DMC's configuration
+ * @dmc:	device for which is going to be checked and configured
+ *
+ * Function checks the HW product information in order to choose proper
+ * configuration for DMC frequency, voltage and DRAM timings.
+ */
+static int exynos5_dmc_chip_revision_settings(struct exynos5_dmc *dmc)
+{
+	unsigned int val;
+
+	val = readl(dmc->chip_id + EXYNOS5_CHIP_PROD_ID);
+	dmc->prod_rev = val;
+
+	val = readl(dmc->chip_id + EXYNOS5_CHIP_PKG_ID);
+	dmc->pkg_rev = val;
+
+	dmc->mem_info = EXYNOS5_POP_OPTIONS(val);
+	dmc->mem_info |= EXYNOS5_DDR_TYPE(val);
+
+	if (!IS_MEM_2GB(dmc->mem_info)) {
+		dev_warn(dmc->dev, "DRAM memory type not supported\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * exynos5_switch_timing_regs() - Changes bank register set for DRAM timings
+ * @dmc:	device for which the new settings is going to be applied
+ * @set:	boolean variable passing set value
+ *
+ * Changes the register set, which holds timing parameters.
+ * There is two register sets: 0 and 1. The register set 0
+ * is used in normal operation when the clock is provided from main PLL.
+ * The bank register set 1 is used when the main PLL frequency is going to be
+ * changed and the clock is taken from alternative, stable source.
+ * This function switches between these banks according to the
+ * currently used clock source.
+ */
+static void exynos5_switch_timing_regs(struct exynos5_dmc *dmc, bool set)
+{
+	unsigned int reg;
+	int ret;
+
+	ret = regmap_read(dmc->clk_regmap, CDREX_LPDDR3PHY_CON3, &reg);
+
+	if (set)
+		reg |= EXYNOS5_TIMING_SET_SWI;
+	else
+		reg &= ~EXYNOS5_TIMING_SET_SWI;
+
+	regmap_write(dmc->clk_regmap, CDREX_LPDDR3PHY_CON3, reg);
+}
+
+/**
+ * exynos5_init_freq_table() - Initialized PM OPP framework
+ * @dev:	devfreq device for which the OPP table is going to be
+ *		initialized
+ * @dmc:	DMC device for which the frequencies are used for OPP init
+ * @profile:	devfreq device's profile
+ *
+ * Populate the devfreq device's OPP table based on current frequency, voltage.
+ */
+static int exynos5_init_freq_table(struct device *dev, struct exynos5_dmc *dmc,
+				   struct devfreq_dev_profile *profile)
+{
+	int i, ret;
+	int idx;
+	unsigned long freq;
+
+	ret = dev_pm_opp_of_add_table(dev);
+	if (ret < 0) {
+		dev_err(dev, "Failed to get OPP table\n");
+		return ret;
+	}
+
+	dmc->opp_count = dev_pm_opp_get_opp_count(dev);
+
+	dmc->opp = devm_kmalloc_array(dmc->dev, dmc->opp_count,
+				      sizeof(struct dmc_opp_table), GFP_KERNEL);
+	if (!dmc->opp)
+		goto err_opp;
+
+	idx = dmc->opp_count - 1;
+	for (i = 0, freq = ULONG_MAX; i < dmc->opp_count; i++, freq--) {
+		struct dev_pm_opp *opp;
+
+		opp = dev_pm_opp_find_freq_floor(dev, &freq);
+		if (IS_ERR(opp))
+			goto err_free_tables;
+
+		dmc->opp[idx - i].freq_hz = freq;
+		dmc->opp[idx - i].volt_uv = dev_pm_opp_get_voltage(opp);
+
+		dev_pm_opp_put(opp);
+	}
+
+	return 0;
+
+err_free_tables:
+	kfree(dmc->opp);
+err_opp:
+	dev_pm_opp_of_remove_table(dev);
+
+	return -EINVAL;
+}
+
+/**
+ * exynos5_set_bypass_dram_timings() - Low-level changes of the DRAM timings
+ * @dmc:	device for which the new settings is going to be applied
+ * @param:	DRAM parameters which passes timing data
+ *
+ * Low-level function for changing timings for DRAM memory clocking from
+ * 'bypass' clock source (fixed frequency @400MHz).
+ * It uses timing bank registers set 1.
+ */
+static void exynos5_set_bypass_dram_timings(struct exynos5_dmc *dmc)
+{
+	writel(EXYNOS5_AREF_NORMAL,
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
+
+	writel(dmc->bypass_timing_row,
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW1);
+	writel(dmc->bypass_timing_row,
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW1);
+	writel(dmc->bypass_timing_data,
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA1);
+	writel(dmc->bypass_timing_data,
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA1);
+	writel(dmc->bypass_timing_power,
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER1);
+	writel(dmc->bypass_timing_power,
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER1);
+}
+
+/**
+ * exynos5_dram_change_timings() - Low-level changes of the DRAM final timings
+ * @dmc:	device for which the new settings is going to be applied
+ * @target_rate:	target frequency of the DMC
+ *
+ * Low-level function for changing timings for DRAM memory operating from main
+ * clock source (BPLL), which can have different frequencies. Thus, each
+ * frequency must have corresponding timings register values in order to keep
+ * the needed delays.
+ * It uses timing bank registers set 0.
+ */
+static int exynos5_dram_change_timings(struct exynos5_dmc *dmc,
+				       unsigned long target_rate)
+{
+	int idx;
+
+	for (idx = dmc->opp_count - 1; idx >= 0; idx--)
+		if (dmc->opp[idx].freq_hz <= target_rate)
+			break;
+
+	if (idx < 0)
+		return -EINVAL;
+
+	writel(EXYNOS5_AREF_NORMAL,
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
+
+	writel(dmc->timing_row[idx],
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW0);
+	writel(dmc->timing_row[idx],
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW0);
+	writel(dmc->timing_data[idx],
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA0);
+	writel(dmc->timing_data[idx],
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA0);
+	writel(dmc->timing_power[idx],
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER0);
+	writel(dmc->timing_power[idx],
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER0);
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_align_target_voltage() - Sets the final voltage for the DMC
+ * @dmc:	device for which it is going to be set
+ * @target_volt:	new voltage which is chosen to be final
+ *
+ * Function tries to align voltage to the safe level for 'normal' mode.
+ * It checks the need of higher voltage and changes the value. The target
+ * voltage might be lower that currently set and still the system will be
+ * stable.
+ */
+static int exynos5_dmc_align_target_voltage(struct exynos5_dmc *dmc,
+					    unsigned long target_volt)
+{
+	int ret = 0;
+
+	if (dmc->curr_volt > target_volt) {
+		ret = regulator_set_voltage(dmc->vdd_mif, target_volt,
+					    target_volt);
+		if (!ret)
+			dmc->curr_volt = target_volt;
+	}
+
+	return ret;
+}
+
+/**
+ * exynos5_dmc_align_bypass_voltage() - Sets the voltage for the DMC
+ * @dmc:	device for which it is going to be set
+ * @target_volt:	new voltage which is chosen to be final
+ *
+ * Function tries to align voltage to the safe level for the 'bypass' mode.
+ * It checks the need of higher voltage and changes the value.
+ * The target voltage must not be less than currently needed, because
+ * for current frequency the device might become unstable.
+ */
+static int exynos5_dmc_align_bypass_voltage(struct exynos5_dmc *dmc,
+					    unsigned long target_volt)
+{
+	int ret = 0;
+	unsigned long bypass_volt = dmc->opp_bypass.volt_uv;
+
+	target_volt = max(bypass_volt, target_volt);
+
+	if (dmc->curr_volt >= target_volt)
+		return 0;
+
+	ret = regulator_set_voltage(dmc->vdd_mif, target_volt,
+				    target_volt);
+	if (!ret)
+		dmc->curr_volt = target_volt;
+
+	return ret;
+}
+
+/**
+ * exynos5_dmc_align_bypass_dram_timings() - Chooses and sets DRAM timings
+ * @dmc:	device for which it is going to be set
+ * @target_rate:	new frequency which is chosen to be final
+ *
+ * Function changes the DRAM timings for the temporary 'bypass' mode.
+ */
+static int exynos5_dmc_align_bypass_dram_timings(struct exynos5_dmc *dmc,
+						 unsigned long target_rate)
+{
+	int idx = find_target_freq_idx(dmc, target_rate);
+
+	if (idx < 0)
+		return -EINVAL;
+
+	exynos5_set_bypass_dram_timings(dmc);
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_switch_to_bypass_configuration() - Switching to temporary clock
+ * @dmc:	DMC device for which the switching is going to happen
+ * @target_rate:	new frequency which is going to be set as a final
+ * @target_volt:	new voltage which is going to be set as a final
+ *
+ * Function configures DMC and clocks for operating in temporary 'bypass' mode.
+ * This mode is used only temporary but if required, changes voltage and timings
+ * for DRAM chips. It switches the main clock to stable clock source for the
+ * period of the main PLL reconfiguration.
+ */
+static int exynos5_dmc_switch_to_bypass_configuration(struct exynos5_dmc *dmc,
+				   unsigned long target_rate,
+				   unsigned long target_volt)
+{
+	int ret;
+
+	/*
+	 * Having higher voltage for a particular frequency does not harm
+	 * the chip. Use it for the temporary frequency change when one
+	 * voltage manipulation might be avoided.
+	 */
+	ret = exynos5_dmc_align_bypass_voltage(dmc, target_volt);
+	if (ret)
+		return ret;
+
+	/*
+	 * Longer delays for DRAM does not cause crash, the opposite does.
+	 */
+	ret = exynos5_dmc_align_bypass_dram_timings(dmc, target_rate);
+	if (ret)
+		return ret;
+
+	/*
+	 * Delays are long enough, so use them for the new coming clock.
+	 */
+	exynos5_switch_timing_regs(dmc, USE_MX_MSPLL_TIMINGS);
+
+	/*
+	 * Voltage is set at least to a level needed for this frequency,
+	 * so switching clock source is safe now.
+	 */
+	clk_prepare_enable(dmc->fout_spll);
+	clk_prepare_enable(dmc->mout_spll);
+	clk_prepare_enable(dmc->mout_mx_mspll_ccore);
+
+	ret = clk_set_parent(dmc->mout_mclk_cdrex, dmc->mout_mx_mspll_ccore);
+
+	return ret;
+}
+
+/**
+ * exynos5_dmc_change_freq_and_volt() - Changes voltage and frequency of the DMC
+ * using safe procedure
+ * @dmc:	device for which the frequency is going to be changed
+ * @target_rate:	requested new frequency
+ * @target_volt:	requested voltage which corresponds to the new frequency
+ *
+ * The DMC frequency change procedure requires a few steps.
+ * The main requirement is to change the clock source in the clk mux
+ * for the time of main clock PLL locking. The assumption is that the
+ * alternative clock source set as parent is stable.
+ * The second parent's clock frequency is fixed to 400MHz, it is named 'bypass'
+ * clock. This requires alignment in DRAM timing parameters for the new
+ * T-period. There is two bank sets for keeping DRAM
+ * timings: set 0 and set 1. The set 0 is used when main clock source is
+ * chosen. The 2nd set of regs is used for 'bypass' clock. Switching between
+ * the two bank sets is part of the process.
+ * The voltage must also be aligned to the minimum required level. There is
+ * this intermediate step with switching to 'bypass' parent clock source.
+ * if the old voltage is lower, it requires an increase of the voltage level.
+ * The complexity of the voltage manipulation is hidden in low level function.
+ * In this function there is last alignment of the voltage level at the end.
+ */
+static int
+exynos5_dmc_change_freq_and_volt(struct exynos5_dmc *dmc,
+				 unsigned long target_rate,
+				 unsigned long target_volt)
+{
+	int ret;
+
+	ret = exynos5_dmc_switch_to_bypass_configuration(dmc, target_rate,
+							 target_volt);
+	if (ret)
+		return ret;
+
+	/* We are safe to increase the timings for current bypass frequency.
+	 * Thanks to this the settings we be ready for the upcoming clock source
+	 * change.
+	 */
+	exynos5_dram_change_timings(dmc, target_rate);
+
+	clk_set_rate(dmc->fout_bpll, target_rate);
+
+	exynos5_switch_timing_regs(dmc, USE_BPLL_TIMINGS);
+
+	ret = clk_set_parent(dmc->mout_mclk_cdrex, dmc->mout_bpll);
+	if (ret)
+		return ret;
+
+	clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
+	clk_disable_unprepare(dmc->mout_spll);
+	clk_disable_unprepare(dmc->fout_spll);
+	/* Make sure if the voltage is not from 'bypass' settings and align to
+	 * the right level for power efficiency.
+	 */
+	ret = exynos5_dmc_align_target_voltage(dmc, target_volt);
+
+	return ret;
+}
+
+/**
+ * exynos5_dmc_get_volt_freq() - Gets the frequency and voltage from the OPP
+ * table.
+ * @dev:	device for which the frequency is going to be changed
+ * @freq:       requested frequency in KHz
+ * @target_rate:	returned frequency which is the same or lower than
+ *			requested
+ * @target_volt:	returned voltage which corresponds to the returned
+ *			frequency
+ *
+ * Function gets requested frequency and checks OPP framework for needed
+ * frequency and voltage. It populates the values 'target_rate' and
+ * 'target_volt' or returns error value when OPP framework fails.
+ */
+static int exynos5_dmc_get_volt_freq(struct device *dev, unsigned long *freq,
+				     unsigned long *target_rate,
+				     unsigned long *target_volt, u32 flags)
+{
+	struct dev_pm_opp *opp;
+
+	opp = devfreq_recommended_opp(dev, freq, flags);
+	if (IS_ERR(opp))
+		return PTR_ERR(opp);
+
+	*target_rate = dev_pm_opp_get_freq(opp);
+	*target_volt = dev_pm_opp_get_voltage(opp);
+	dev_pm_opp_put(opp);
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_target() - Function responsible for changing frequency of DMC
+ * @dev:	device for which the frequency is going to be changed
+ * @freq:	requested frequency in KHz
+ * @flags:	flags provided for this frequency change request
+ *
+ * An entry function provided to the devfreq framework which provides frequency
+ * change of the DMC. The function gets the possible rate from OPP table based
+ * on requested frequency. It calls the next function responsible for the
+ * frequency and voltage change. In case of failure, does not set 'curr_rate'
+ * and returns error value to the framework.
+ */
+static int exynos5_dmc_target(struct device *dev, unsigned long *freq,
+			      u32 flags)
+{
+	struct exynos5_dmc *dmc = dev_get_drvdata(dev);
+	unsigned long target_rate = 0;
+	unsigned long target_volt = 0;
+	int ret;
+
+	ret = exynos5_dmc_get_volt_freq(dev, freq, &target_rate, &target_volt,
+					flags);
+
+	if (ret)
+		return ret;
+
+	if (target_rate == dmc->curr_rate)
+		return 0;
+
+	mutex_lock(&dmc->lock);
+
+	ret = exynos5_dmc_change_freq_and_volt(dmc, target_rate, target_volt);
+
+	if (ret) {
+		mutex_unlock(&dmc->lock);
+		return ret;
+	}
+
+	dmc->curr_rate = target_rate;
+
+	mutex_unlock(&dmc->lock);
+	return 0;
+}
+
+/**
+ * exynos5_counters_get() - Gets the performance counters values.
+ * @dmc:	device for which the counters are going to be checked
+ * @load_count:	variable which is populated with counter value
+ * @total_count:	variable which is used as 'wall clock' reference
+ *
+ * Function which provides performance counters values. It sums up counters for
+ * two DMC channels. The 'total_count' is used as a reference and max value.
+ * The ratio 'load_count/total_count' shows the busy percentage [0%, 100%].
+ */
+static int exynos5_counters_get(struct exynos5_dmc *dmc,
+				unsigned long *load_count,
+				unsigned long *total_count)
+{
+	unsigned long total = 0;
+	struct devfreq_event_data event;
+	int ret, i;
+
+	*load_count = 0;
+
+	/* Take into account only read+write counters, but stop all */
+	for (i = 0; i < dmc->num_counters; i++) {
+		if (!dmc->counter[i])
+			continue;
+
+		ret = devfreq_event_get_event(dmc->counter[i], &event);
+		if (ret < 0)
+			return ret;
+
+		if (i % 3 != 2)
+			continue;
+
+		*load_count += event.load_count;
+
+		if (total < event.total_count)
+			total = event.total_count;
+	}
+
+	*total_count = total;
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_get_status() - Read current DMC performance statistics.
+ * @dev:	device for which the statistics are requested
+ * @stat:	structure which has statistic fields
+ *
+ * Function reads the DMC performance counters and calculates 'busy_time'
+ * and 'total_time'. To protect from overflow, the values are shifted right
+ * by 10. After read out the counters are setup to count again.
+ */
+static int exynos5_dmc_get_status(struct device *dev,
+				  struct devfreq_dev_status *stat)
+{
+	struct exynos5_dmc *dmc = dev_get_drvdata(dev);
+	unsigned long load, total;
+	int ret;
+	bool cnt_en;
+
+	mutex_lock(&dmc->lock);
+	cnt_en = dmc->counters_enabled;
+	mutex_unlock(&dmc->lock);
+	if (!cnt_en) {
+		dev_warn(dev, "performance counters needed, but not present\n");
+		return -EAGAIN;
+	}
+
+	ret = exynos5_counters_get(dmc, &load, &total);
+	if (ret < 0)
+		return -EINVAL;
+
+	/* To protect from overflow in calculation ratios, divide by 1024 */
+	stat->busy_time = load >> 10;
+	stat->total_time = total >> 10;
+
+	ret = exynos5_counters_set_event(dmc);
+	if (ret < 0) {
+		dev_err(dmc->dev, "could not set event counter\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_get_cur_freq() - Function returns current DMC frequency
+ * @dev:	device for which the framework checks operating frequency
+ * @freq:	returned frequency value
+ *
+ * It returns the currently used frequency of the DMC. The real operating
+ * frequency might be lower when the clock source value could not be divided
+ * to the requested value.
+ */
+static int exynos5_dmc_get_cur_freq(struct device *dev, unsigned long *freq)
+{
+	struct exynos5_dmc *dmc = dev_get_drvdata(dev);
+
+	mutex_lock(&dmc->lock);
+	*freq = dmc->curr_rate;
+	mutex_unlock(&dmc->lock);
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_df_profile - Devfreq governor's profile structure
+ *
+ * It provides to the devfreq framework needed functions and polling period.
+ */
+static struct devfreq_dev_profile exynos5_dmc_df_profile = {
+	.polling_ms = 500,
+	.target = exynos5_dmc_target,
+	.get_dev_status = exynos5_dmc_get_status,
+	.get_cur_freq = exynos5_dmc_get_cur_freq,
+};
+
+/**
+ * exynos5_dmc_align_initial_frequency() - Align initial frequency value
+ * @dmc:	device for which the frequency is going to be set
+ * @bootloader_init_freq:	initial frequency set by the bootloader in KHz
+ *
+ * The initial bootloader frequency, which is present during boot, might be
+ * different that supported frequency values in the driver. It is possible
+ * due to different PLL settings or used PLL as a source.
+ * This function provides the 'initial_freq' for the devfreq framework
+ * statistics engine which supports only registered values. Thus, some alignment
+ * must be made.
+ */
+unsigned long
+exynos5_dmc_align_init_freq(struct exynos5_dmc *dmc,
+			    unsigned long bootloader_init_freq)
+{
+	unsigned long aligned_freq;
+	int idx;
+
+	idx = find_target_freq_idx(dmc, bootloader_init_freq);
+	if (idx >= 0)
+		aligned_freq = dmc->opp[idx].freq_hz;
+	else
+		aligned_freq = dmc->opp[dmc->opp_count - 1].freq_hz;
+
+	return aligned_freq;
+}
+
+/**
+ * create_timings_aligned() - Create register values and align with standard
+ * @dmc:	device for which the frequency is going to be set
+ * @idx:	speed bin in the OPP table
+ * @clk_period_ps:	the period of the clock, known as tCK
+ *
+ * The function calculates timings and creates a register value ready for
+ * a frequency transition. The register contains a few timings. They are
+ * shifted by a known offset. The timing value is calculated based on memory
+ * specyfication: minimal time required and minimal cycles required.
+ */
+static int create_timings_aligned(struct exynos5_dmc *dmc, u32 *reg_timing_row,
+				  u32 *reg_timing_data, u32 *reg_timing_power,
+				  u32 clk_period_ps)
+{
+	u32 val;
+	struct timing_reg *reg;
+
+	if (clk_period_ps == 0)
+		return -EINVAL;
+
+	*reg_timing_row = 0;
+	*reg_timing_data = 0;
+	*reg_timing_power = 0;
+
+	val = dmc->timings->tRFC / clk_period_ps;
+	val += dmc->timings->tRFC % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tRFC);
+	reg = &timing_row[0];
+	*reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tRRD / clk_period_ps;
+	val += dmc->timings->tRRD % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tRRD);
+	reg = &timing_row[1];
+	*reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tRPab / clk_period_ps;
+	val += dmc->timings->tRPab % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tRPab);
+	reg = &timing_row[2];
+	*reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tRCD / clk_period_ps;
+	val += dmc->timings->tRCD % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tRCD);
+	reg = &timing_row[3];
+	*reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tRC / clk_period_ps;
+	val += dmc->timings->tRC % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tRC);
+	reg = &timing_row[4];
+	*reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tRAS / clk_period_ps;
+	val += dmc->timings->tRAS % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tRAS);
+	reg = &timing_row[5];
+	*reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+	/* data related timings */
+	val = dmc->timings->tWTR / clk_period_ps;
+	val += dmc->timings->tWTR % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tWTR);
+	reg = &timing_data[0];
+	*reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tWR / clk_period_ps;
+	val += dmc->timings->tWR % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tWR);
+	reg = &timing_data[1];
+	*reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tRTP / clk_period_ps;
+	val += dmc->timings->tRTP % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tRTP);
+	reg = &timing_data[2];
+	*reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tW2W_C2C / clk_period_ps;
+	val += dmc->timings->tW2W_C2C % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tW2W_C2C);
+	reg = &timing_data[3];
+	*reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tR2R_C2C / clk_period_ps;
+	val += dmc->timings->tR2R_C2C % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tR2R_C2C);
+	reg = &timing_data[4];
+	*reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tWL / clk_period_ps;
+	val += dmc->timings->tWL % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tWL);
+	reg = &timing_data[5];
+	*reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tDQSCK / clk_period_ps;
+	val += dmc->timings->tDQSCK % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tDQSCK);
+	reg = &timing_data[6];
+	*reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tRL / clk_period_ps;
+	val += dmc->timings->tRL % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tRL);
+	reg = &timing_data[7];
+	*reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+	/* power related timings */
+	val = dmc->timings->tFAW / clk_period_ps;
+	val += dmc->timings->tFAW % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tXP);
+	reg = &timing_power[0];
+	*reg_timing_power |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tXSR / clk_period_ps;
+	val += dmc->timings->tXSR % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tXSR);
+	reg = &timing_power[1];
+	*reg_timing_power |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tXP / clk_period_ps;
+	val += dmc->timings->tXP % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tXP);
+	reg = &timing_power[2];
+	*reg_timing_power |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tCKE / clk_period_ps;
+	val += dmc->timings->tCKE % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tCKE);
+	reg = &timing_power[3];
+	*reg_timing_power |= TIMING_VAL2REG(reg, val);
+
+	val = dmc->timings->tMRD / clk_period_ps;
+	val += dmc->timings->tMRD % clk_period_ps ? 1 : 0;
+	val = max(val, dmc->min_tck->tMRD);
+	reg = &timing_power[4];
+	*reg_timing_power |= TIMING_VAL2REG(reg, val);
+
+	return 0;
+}
+
+/**
+ * of_get_dram_timings() - helper function for parsing DT settings for DRAM
+ * @dmc:        device for which the frequency is going to be set
+ *
+ * The function parses DT entries with DRAM information.
+ */
+static int of_get_dram_timings(struct exynos5_dmc *dmc)
+{
+	int ret = 0;
+	struct device_node *np;
+	int idx;
+	struct device_node *np_ddr;
+	u32 freq_mhz, clk_period_ps;
+
+	np_ddr = of_parse_phandle(dmc->dev->of_node, "device-handle", 0);
+	if (!np_ddr) {
+		dev_warn(dmc->dev, "could not find 'device-handle' in DT\n");
+		return -EINVAL;
+	}
+
+	dmc->timing_row = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
+					     sizeof(u32), GFP_KERNEL);
+	if (!dmc->timing_row)
+		return -ENOMEM;
+
+	dmc->timing_data = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
+					      sizeof(u32), GFP_KERNEL);
+	if (!dmc->timing_data)
+		return -ENOMEM;
+
+	dmc->timing_power = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
+					       sizeof(u32), GFP_KERNEL);
+	if (!dmc->timing_power)
+		return -ENOMEM;
+
+	dmc->timings = of_lpddr3_get_ddr_timings(np_ddr, dmc->dev,
+						 DDR_TYPE_LPDDR3,
+						 &dmc->timings_arr_size);
+	if (!dmc->timings) {
+		of_node_put(np_ddr);
+		dev_warn(dmc->dev, "could not get timings from DT\n");
+		return -EINVAL;
+	}
+
+	dmc->min_tck = of_lpddr3_get_min_tck(np_ddr, dmc->dev);
+	if (!dmc->min_tck) {
+		of_node_put(np_ddr);
+		dev_warn(dmc->dev, "could not get tck from DT\n");
+		return -EINVAL;
+	}
+
+	/* Sorted array of OPPs with frequency ascending */
+	for (idx = 0; idx < dmc->opp_count; idx++) {
+		freq_mhz = dmc->opp[idx].freq_hz / 1000000;
+		clk_period_ps = 1000000 / freq_mhz;
+
+		ret = create_timings_aligned(dmc, &dmc->timing_row[idx],
+					     &dmc->timing_data[idx],
+					     &dmc->timing_power[idx],
+					     clk_period_ps);
+	}
+
+	of_node_put(np);
+
+	/* Take the highest frequency's timings as 'bypass' */
+	dmc->bypass_timing_row = dmc->timing_row[idx - 1];
+	dmc->bypass_timing_data = dmc->timing_data[idx - 1];
+	dmc->bypass_timing_power = dmc->timing_power[idx - 1];
+
+	return ret;
+}
+
+/**
+ * exynos5_dmc_init_clks() - Initialize clocks needed for DMC operation.
+ * @dev:	device for which the clocks are setup
+ * @dmc:	DMC structure containing needed fields
+ *
+ * Get the needed clocks defined in DT device, enable and set the right parents.
+ * Read current frequency and initialize the initial rate for governor.
+ */
+static int exynos5_dmc_init_clks(struct device *dev, struct exynos5_dmc *dmc)
+{
+	int ret;
+	unsigned long target_volt = 0;
+	unsigned long target_rate = 0;
+
+	dmc->fout_spll = devm_clk_get(dev, "fout_spll");
+	if (IS_ERR(dmc->fout_spll))
+		return PTR_ERR(dmc->fout_spll);
+
+	dmc->fout_bpll = devm_clk_get(dev, "fout_bpll");
+	if (IS_ERR(dmc->fout_bpll))
+		return PTR_ERR(dmc->fout_bpll);
+
+	dmc->mout_mclk_cdrex = devm_clk_get(dev, "mout_mclk_cdrex");
+	if (IS_ERR(dmc->mout_mclk_cdrex))
+		return PTR_ERR(dmc->mout_mclk_cdrex);
+
+	dmc->mout_bpll = devm_clk_get(dev, "mout_bpll");
+	if (IS_ERR(dmc->mout_bpll))
+		return PTR_ERR(dmc->mout_bpll);
+
+	dmc->mout_mx_mspll_ccore = devm_clk_get(dev, "mout_mx_mspll_ccore");
+	if (IS_ERR(dmc->mout_mx_mspll_ccore))
+		return PTR_ERR(dmc->mout_mx_mspll_ccore);
+
+	dmc->dout_clk2x_phy0 = devm_clk_get(dev, "dout_clk2x_phy0");
+	if (IS_ERR(dmc->dout_clk2x_phy0))
+		return PTR_ERR(dmc->dout_clk2x_phy0);
+
+	dmc->mout_spll = devm_clk_get(dev, "ff_dout_spll2");
+	if (IS_ERR(dmc->mout_spll)) {
+		dmc->mout_spll = devm_clk_get(dev, "mout_sclk_spll");
+		if (IS_ERR(dmc->mout_spll))
+			return PTR_ERR(dmc->mout_spll);
+	}
+
+	/*
+	 * Convert frequency to KHz values and set it for the governor.
+	 */
+	dmc->curr_rate = clk_get_rate(dmc->mout_mclk_cdrex);
+	dmc->curr_rate = exynos5_dmc_align_init_freq(dmc, dmc->curr_rate);
+	exynos5_dmc_df_profile.initial_freq = dmc->curr_rate;
+
+	ret = exynos5_dmc_get_volt_freq(dev, &dmc->curr_rate, &target_rate,
+					&target_volt, 0);
+	if (ret)
+		return ret;
+
+	dmc->curr_volt = target_volt;
+
+	clk_prepare_enable(dmc->mout_spll);
+	clk_set_parent(dmc->mout_mx_mspll_ccore, dmc->mout_spll);
+	clk_prepare_enable(dmc->mout_mx_mspll_ccore);
+
+	dmc->bypass_rate = clk_get_rate(dmc->mout_mx_mspll_ccore);
+
+	clk_prepare_enable(dmc->fout_bpll);
+	clk_prepare_enable(dmc->mout_bpll);
+
+	return 0;
+}
+
+/**
+ * exynos5_performance_counters_init() - Initializes performance DMC's counters
+ * @dmc:	DMC for which it does the setup
+ *
+ * Initialization of performance counters in DMC for estimating usage.
+ * The counter's values are used for calculation of a memory bandwidth and based
+ * on that the governor changes the frequency.
+ * The counters are not used when the governor is GOVERNOR_USERSPACE.
+ */
+static int exynos5_performance_counters_init(struct exynos5_dmc *dmc)
+{
+	int counters_size;
+	int ret, i;
+
+	dmc->num_counters = devfreq_event_get_edev_count(dmc->dev);
+	if (dmc->num_counters < 0) {
+		dev_err(dmc->dev, "could not get devfreq-event counters\n");
+		return dmc->num_counters;
+	}
+
+	counters_size = sizeof(struct devfreq_event_dev) * dmc->num_counters;
+	dmc->counter = devm_kzalloc(dmc->dev, counters_size, GFP_KERNEL);
+	if (!dmc->counter)
+		return -ENOMEM;
+
+	for (i = 0; i < dmc->num_counters; i++) {
+		dmc->counter[i] =
+			devfreq_event_get_edev_by_phandle(dmc->dev, i);
+		if (IS_ERR_OR_NULL(dmc->counter[i]))
+			return -EPROBE_DEFER;
+	}
+
+	ret = exynos5_counters_enable_edev(dmc);
+	if (ret < 0) {
+		dev_err(dmc->dev, "could not enable event counter\n");
+		return ret;
+	}
+
+	ret = exynos5_counters_set_event(dmc);
+	if (ret < 0) {
+		dev_err(dmc->dev, "counld not set event counter\n");
+		return ret;
+	}
+
+	mutex_lock(&dmc->lock);
+	dmc->counters_enabled = true;
+	mutex_unlock(&dmc->lock);
+
+	return 0;
+}
+
+static struct regmap_config exynos5_clk_regmap_cfg = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+};
+
+static int exynos5_dmc_init_clk_regmap(struct platform_device *pdev,
+				       struct exynos5_dmc *dmc)
+{
+	struct resource *res;
+	void __iomem *base;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
+	base = devm_ioremap_resource(dmc->dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	exynos5_clk_regmap_cfg.max_register = resource_size(res) - 4;
+	dmc->clk_regmap = devm_regmap_init_mmio(dmc->dev, base,
+					     &exynos5_clk_regmap_cfg);
+	if (IS_ERR(dmc->clk_regmap))
+		return PTR_ERR(dmc->clk_regmap);
+
+	return 0;
+}
+
+#ifdef CONFIG_DEBUG_FS
+
+static int dmc_dbg_show_timings(struct seq_file *seq, void *na)
+{
+	struct exynos5_dmc *dmc = seq->private;
+	int i, j;
+	u32 val;
+	struct timing_reg *reg;
+
+	seq_printf(seq, "timings for each frequency\n");
+	for (j = dmc->opp_count - 1; j >= 0; j--) {
+		seq_printf(seq, "frequency = %uMHz\n",
+				   dmc->opp[j].freq_hz / 1000000);
+		seq_printf(seq, "timing_row, timing_data, timing_power\n");
+		seq_printf(seq, "0x%08X, 0x%08X, 0x%08X\n", dmc->timing_row[j],
+			   dmc->timing_data[j], dmc->timing_power[j]);
+	}
+
+	for (j = dmc->opp_count - 1; j >= 0; j--) {
+		seq_printf(seq, "frequency [MHz] = %u\n",
+				   dmc->opp[j].freq_hz / 1000000);
+
+		for (i = 0; i < ARRAY_SIZE(timing_row); i++) {
+			reg = &timing_row[i];
+			val = TIMING_REG2VAL(dmc->timing_row[j], reg);
+			seq_printf(seq, "%s = %u\n", reg->name, val);
+		}
+
+		for (i = 0; i < ARRAY_SIZE(timing_data); i++) {
+			reg = &timing_data[i];
+			val = TIMING_REG2VAL(dmc->timing_data[j], reg);
+			seq_printf(seq, "%s = %u\n", reg->name, val);
+		}
+
+		for (i = 0; i < ARRAY_SIZE(timing_power); i++) {
+			reg = &timing_power[i];
+			val = TIMING_REG2VAL(dmc->timing_power[j], reg);
+			seq_printf(seq, "%s = %u\n", reg->name, val);
+		}
+	}
+
+	return 0;
+}
+
+static int dmc_dbg_open_timings(struct inode *inode, struct file *f)
+{
+	return single_open(f, dmc_dbg_show_timings, inode->i_private);
+}
+
+static const char *event_get_name(const char *evt)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(event_name); i += 2) {
+		if (!strcmp(event_name[i], evt))
+			return event_name[i + 1];
+	}
+
+	return "Unknown";
+}
+
+static int dmc_dbg_show_cnt(struct seq_file *seq, void *na)
+{
+	struct exynos5_dmc *dmc = seq->private;
+	int i;
+	struct devfreq_event_data event;
+	struct devfreq_event_dev *edev;
+	int ret;
+	const char *evt_name;
+	u64 ts_new, delta;
+	static u64 ts;
+
+	seq_printf(seq, "Performance based on PMU counters\n");
+	seq_printf(seq, "The counters could overflow every ~9.2 sec\n");
+
+	ts_new = ktime_get_ns();
+	delta = ts_new - ts;
+
+	for (i = 0; i < dmc->num_counters; i++) {
+		edev = dmc->counter[i];
+		if (!edev)
+			continue;
+
+		evt_name = event_get_name(edev->desc->name);
+
+		ret = devfreq_event_get_event(edev, &event);
+		if (ret < 0)
+			return ret;
+
+		seq_printf(seq, "%s = %lu / %lu\n", evt_name, event.load_count,
+			   event.total_count);
+	}
+
+	seq_printf(seq, "For last %llu ms\n",
+		   div64_u64(delta, 1000000UL));
+
+	ts = ktime_get_ns();
+	ret = exynos5_counters_set_event(dmc);
+	if (ret < 0) {
+		dev_err(dmc->dev, "could not set event counter\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int dmc_dbg_open_cnt(struct inode *inode, struct file *f)
+{
+	return single_open(f, dmc_dbg_show_cnt, inode->i_private);
+}
+
+struct counter {
+	u64 load;
+	u64 total;
+};
+
+static int dmc_dbg_show_cnt_100ms(struct seq_file *seq, void *na)
+{
+	struct exynos5_dmc *dmc = seq->private;
+	int i;
+	u64 bandwidth = 0;
+	struct devfreq_event_data event;
+	struct devfreq_event_dev *edev;
+	int ret;
+	const char *evt_name;
+	u64 ts_new, delta;
+	static u64 ts;
+	struct counter *cnt;
+	u64 total[3] = {0, 0, 0 }; /* read, write, read+write data*/
+	const char *type[3] = {"read", "write", "read+write"};
+	u64 bus_cyc_count = 0;
+	int offset = 0;
+	char *s;
+
+	s = kzalloc(PAGE_SIZE * sizeof(char), GFP_KERNEL);
+	if (!s)
+		return -ENOMEM;
+
+	cnt = kcalloc(dmc->num_counters, sizeof(struct counter), GFP_KERNEL);
+	if (!cnt)
+		return -ENOMEM;
+
+	ret = exynos5_counters_set_event(dmc);
+	if (ret < 0) {
+		dev_err(dmc->dev, "could not set event counter\n");
+		return ret;
+	}
+
+	ts = ktime_get_ns();
+	msleep(100);
+
+	/* Seprate data acquisition from presentation due to some
+	   overheads. */
+	for (i = 0; i < dmc->num_counters; i++) {
+		edev = dmc->counter[i];
+		if (!edev)
+			continue;
+
+		ret = devfreq_event_get_event(edev, &event);
+		if (ret < 0)
+			return ret;
+
+		total[i % 3] += event.load_count;
+		cnt[i].load = event.load_count;
+		cnt[i].total = event.total_count;
+
+		if (bus_cyc_count < event.total_count)
+			bus_cyc_count = event.total_count;
+	}
+
+	ts_new = ktime_get_ns();
+	delta = ts_new - ts;
+	if (delta == 0)
+		delta = 1;
+
+	for (i = 0; i < dmc->num_counters; i++) {
+		edev = dmc->counter[i];
+		if (!edev)
+			continue;
+
+		evt_name = event_get_name(edev->desc->name);
+
+		bandwidth = (u64)cnt[i].load * AXI_BUS_WIDTH_BYTES * 1000;
+		bandwidth = div64_u64(bandwidth, delta);
+
+		offset += sprintf(s + offset, "%s\t\t%llu MB/s\n",
+				  evt_name, bandwidth);
+	}
+
+	for (i = 0; i < 3; i++) {
+		bandwidth = (u64)total[i] * AXI_BUS_WIDTH_BYTES * 1000;
+		bandwidth = div64_u64(bandwidth, delta);
+
+		offset += sprintf(s + offset, "total\t%s\t\t%llu MB/s\n",
+				  type[i], bandwidth);
+	}
+
+	/* AXI speed is presented in MHz*/
+	bus_cyc_count *= 1000;
+
+	seq_printf(seq, "Performance based on PMU counters\n");
+	seq_printf(seq, "The counters will overflow every ~9.2 sec\n");
+	seq_printf(seq, "%s", s);
+	seq_printf(seq, "AXI bus frequency %llu MHz, width %u B, SDR mode\n",
+		   div64_u64(bus_cyc_count, delta), AXI_BUS_WIDTH_BYTES);
+	seq_printf(seq, "For last %llu ms\n",
+		   div64_u64(delta, 1000000UL));
+
+	kfree(cnt);
+	kfree(s);
+
+	return 0;
+}
+
+static int dmc_dbg_show_cnt_100ms_raw(struct seq_file *seq, void *na)
+{
+	struct exynos5_dmc *dmc = seq->private;
+	int i;
+	struct devfreq_event_data event;
+	struct devfreq_event_dev *edev;
+	int ret;
+	const char *evt_name;
+	u64 ts_new, delta;
+	static u64 ts;
+	struct counter *cnt;
+	const char *type[3] = {"read", "write", "read+write"};
+	int offset = 0;
+	char *s;
+
+	s = kzalloc(PAGE_SIZE * sizeof(char), GFP_KERNEL);
+	if (!s)
+		return -ENOMEM;
+
+	cnt = kcalloc(dmc->num_counters, sizeof(struct counter), GFP_KERNEL);
+	if (!cnt)
+		return -ENOMEM;
+
+	ret = exynos5_counters_set_event(dmc);
+	if (ret < 0) {
+		dev_err(dmc->dev, "could not set event counter\n");
+		return ret;
+	}
+
+	ts = ktime_get_ns();
+	msleep(100);
+
+	/* Seprate data acquisition from presentation due to some
+	   overheads. */
+	for (i = 0; i < dmc->num_counters; i++) {
+		edev = dmc->counter[i];
+		if (!edev)
+			continue;
+
+		ret = devfreq_event_get_event(edev, &event);
+		if (ret < 0)
+			return ret;
+
+		cnt[i].load = event.load_count;
+		cnt[i].total = event.total_count;
+	}
+
+	ts_new = ktime_get_ns();
+	delta = ts_new - ts;
+	if (delta == 0)
+		delta = 1;
+
+	for (i = 0; i < dmc->num_counters; i++) {
+		edev = dmc->counter[i];
+		if (!edev)
+			continue;
+
+		evt_name = event_get_name(edev->desc->name);
+
+		offset += sprintf(s + offset, "%s (%s)\t\t%llu / %llu\n",
+				  evt_name, type[i % 3], cnt[i].load,
+				  cnt[i].total);
+	}
+
+	seq_printf(seq, "Performance based on PMU counters ('load'/'total')\n");
+	seq_printf(seq, "The counters will overflow every ~9.2 sec\n");
+	seq_printf(seq, "%s", s);
+	seq_printf(seq, "For last %llu ms\n",
+		   div64_u64(delta, 1000000UL));
+
+	kfree(cnt);
+	kfree(s);
+
+	return 0;
+}
+
+static int dmc_dbg_open_cnt_100ms(struct inode *inode, struct file *f)
+{
+	return single_open(f, dmc_dbg_show_cnt_100ms, inode->i_private);
+}
+
+static int dmc_dbg_open_cnt_100ms_raw(struct inode *inode, struct file *f)
+{
+	return single_open(f, dmc_dbg_show_cnt_100ms_raw, inode->i_private);
+}
+
+static const struct file_operations dmc_debugfs_ops_timings = {
+	.open = dmc_dbg_open_timings,
+	.read = seq_read,
+	.release = single_release,
+};
+
+static const struct file_operations dmc_debugfs_ops_cnt = {
+	.open = dmc_dbg_open_cnt,
+	.read = seq_read,
+	.release = single_release,
+};
+
+static const struct file_operations dmc_debugfs_ops_cnt_100ms = {
+	.open = dmc_dbg_open_cnt_100ms,
+	.read = seq_read,
+	.release = single_release,
+};
+
+static const struct file_operations dmc_debugfs_ops_cnt_100ms_raw = {
+	.open = dmc_dbg_open_cnt_100ms_raw,
+	.read = seq_read,
+	.release = single_release,
+};
+
+static void exynos5_dmc_debugfs_init(struct exynos5_dmc *dmc)
+{
+	struct dentry *dentry;
+
+	dmc->dbg_root = debugfs_create_dir(dev_name(dmc->dev), NULL);
+	if (!dmc->dbg_root)
+		return;
+
+	dentry = debugfs_create_file("timings", 0444, dmc->dbg_root, dmc,
+				     &dmc_debugfs_ops_timings);
+	if (!dentry)
+		goto clean_debugfs;
+
+	dentry = debugfs_create_file("counters", 0444, dmc->dbg_root, dmc,
+				     &dmc_debugfs_ops_cnt);
+	if (!dentry)
+		goto clean_debugfs;
+
+	dentry = debugfs_create_file("100ms_counters", 0444, dmc->dbg_root, dmc,
+				     &dmc_debugfs_ops_cnt_100ms);
+	if (!dentry)
+		goto clean_debugfs;
+
+	dentry = debugfs_create_file("100ms_raw_counters", 0444, dmc->dbg_root,
+				     dmc, &dmc_debugfs_ops_cnt_100ms_raw);
+	if (!dentry)
+		goto clean_debugfs;
+
+	return;
+
+clean_debugfs:
+	debugfs_remove_recursive(dmc->dbg_root);
+}
+#else
+static void exynos5_dmc_debugfs_init(struct exynos5_dmc *dmc)
+{}
+#endif
+
+/**
+ * exynos5_dmc_set_pause_on_switching() - Controls a pause feature in DMC
+ * @dmc:	device which is used for changing this feature
+ * @set:	a boolean state passing enable/disable request
+ *
+ * There is a need of pausing DREX DMC when divider or MUX in clock tree
+ * changes its configuration. In such situation access to the memory is blocked
+ * in DMC automatically. This feature is used when clock frequency change
+ * request appears and touches clock tree.
+ */
+static inline int exynos5_dmc_set_pause_on_switching(struct exynos5_dmc *dmc)
+{
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(dmc->clk_regmap, CDREX_PAUSE, &val);
+	if (ret)
+		return ret;
+
+	val |= 1UL;
+	regmap_write(dmc->clk_regmap, CDREX_PAUSE, val);
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_probe() - Probe function for the DMC driver
+ * @pdev:	platform device for which the driver is going to be initialized
+ *
+ * Initialize basic components: clocks, regulators, performance counters, etc.
+ * Read out product version and based on the information setup
+ * internal structures for the controller (frequency and voltage) and for DRAM
+ * memory parameters: timings for each operating frequency.
+ * Register new devfreq device for controlling DVFS of the DMC.
+ */
+static int exynos5_dmc_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+	struct exynos5_dmc *dmc;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+
+	dmc = devm_kzalloc(dev, sizeof(*dmc), GFP_KERNEL);
+	if (!dmc)
+		return -ENOMEM;
+
+	mutex_init(&dmc->lock);
+
+	dmc->dev = dev;
+	platform_set_drvdata(pdev, dmc);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	dmc->base_drexi0 = devm_ioremap_resource(dev, res);
+	if (IS_ERR(dmc->base_drexi0))
+		return PTR_ERR(dmc->base_drexi0);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	dmc->base_drexi1 = devm_ioremap_resource(dev, res);
+	if (IS_ERR(dmc->base_drexi1))
+		return PTR_ERR(dmc->base_drexi1);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	dmc->chip_id = devm_ioremap_resource(dev, res);
+	if (IS_ERR(dmc->chip_id))
+		return PTR_ERR(dmc->chip_id);
+
+	ret = exynos5_dmc_chip_revision_settings(dmc);
+	if (ret)
+		return ret;
+
+	ret = exynos5_init_freq_table(dev, dmc, &exynos5_dmc_df_profile);
+	if (ret) {
+		dev_warn(dev, "couldn't initialize frequency settings\n");
+		return ret;
+	}
+
+	dmc->vdd_mif = devm_regulator_get(dev, "vdd");
+	if (IS_ERR(dmc->vdd_mif)) {
+		ret = PTR_ERR(dmc->vdd_mif);
+		dev_warn(dev, "couldn't get regulator\n");
+		return ret;
+	}
+
+	ret = exynos5_dmc_init_clks(dev, dmc);
+	if (ret) {
+		dev_warn(dev, "couldn't initialize clocks\n");
+		return ret;
+	}
+
+	ret = exynos5_dmc_init_clk_regmap(pdev, dmc);
+	if (ret) {
+		dev_warn(dev, "couldn't initialize clock regmap\n");
+		return ret;
+	}
+
+	ret = of_get_dram_timings(dmc);
+	if (ret) {
+		dev_warn(dev, "couldn't initialize timings settings\n");
+		return ret;
+	}
+
+	ret = exynos5_performance_counters_init(dmc);
+	if (ret) {
+		dev_warn(dev, "couldn't probe performance counters\n");
+		goto remove_clocks;
+	}
+
+	ret = exynos5_dmc_set_pause_on_switching(dmc);
+	if (ret) {
+		dev_warn(dev, "couldn't get access to PAUSE register\n");
+		goto remove_clocks;
+	}
+
+
+	/*
+	 * Setup default thresholds for the devfreq governor.
+	 * The values are chosen based on experiments.
+	 */
+	dmc->gov_data.upthreshold = 30;
+	dmc->gov_data.downdifferential = 5;
+
+	dmc->df = devm_devfreq_add_device(dev, &exynos5_dmc_df_profile,
+					  DEVFREQ_GOV_USERSPACE,
+					  &dmc->gov_data);
+
+	if (IS_ERR(dmc->df)) {
+		ret = PTR_ERR(dmc->df);
+		goto err_devfreq_add;
+	}
+
+	exynos5_dmc_debugfs_init(dmc);
+
+	dev_info(&pdev->dev, "DMC init for prod_id=0x%08x pkg_id=0x%08x\n",
+		 dmc->prod_rev, dmc->pkg_rev);
+
+	return 0;
+
+err_devfreq_add:
+	exynos5_counters_disable_edev(dmc);
+remove_clocks:
+	clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
+	clk_disable_unprepare(dmc->mout_spll);
+
+	return ret;
+}
+
+/**
+ * exynos5_dmc_remove() - Remove function for the platform device
+ * @pdev:	platform device which is going to be removed
+ *
+ * The function relies on 'devm' framework function which automatically
+ * clean the device's resources. It just calls explicitly disable function for
+ * the performance counters.
+ */
+static int exynos5_dmc_remove(struct platform_device *pdev)
+{
+	struct exynos5_dmc *dmc = dev_get_drvdata(&pdev->dev);
+
+	exynos5_counters_disable_edev(dmc);
+
+	clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
+	clk_disable_unprepare(dmc->mout_spll);
+
+	dev_pm_opp_remove_table(&pdev->dev);
+
+	dev_info(&pdev->dev, "DMC removed\n");
+
+	return 0;
+}
+
+static const struct of_device_id exynos5_dmc_of_match[] = {
+	{ .compatible = "samsung,exynos5422-dmc", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, exynos5_dmc_of_match);
+
+static struct platform_driver exynos5_dmc_platdrv = {
+	.probe	= exynos5_dmc_probe,
+	.remove = exynos5_dmc_remove,
+	.driver = {
+		.name	= "exynos5-dmc",
+		.of_match_table = exynos5_dmc_of_match,
+	},
+};
+module_platform_driver(exynos5_dmc_platdrv);
+MODULE_DESCRIPTION("Driver for Exynos5422 Dynamic Memory Controller dynamic frequency and voltage change"
+);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Samsung");
-- 
2.7.4

Re: [PATCH v6 07/10] drivers: memory: add DMC driver for Exynos5422

[Krzysztof Kozlowski]

On Fri, 19 Apr 2019 at 16:19, Lukasz Luba <l.luba@partner.samsung.com> wrote:
>
> This patch adds driver for Exynos5422 Dynamic Memory Controller.
> The driver provides support for dynamic frequency and voltage scaling for
> DMC and DRAM. It supports changing timings of DRAM running with different
> frequency. There is also an algorithm to calculate timigns based on
> memory description provided in DT.
> The patch also contains needed MAINTAINERS file update.
>
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  MAINTAINERS                             |    8 +
>  drivers/memory/samsung/Kconfig          |   17 +
>  drivers/memory/samsung/Makefile         |    1 +
>  drivers/memory/samsung/exynos5422-dmc.c | 1793 +++++++++++++++++++++++++++++++
>  4 files changed, 1819 insertions(+)
>  create mode 100644 drivers/memory/samsung/exynos5422-dmc.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 1ba4b9b..07e257d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -3395,6 +3395,14 @@ S:       Maintained
>  F:     drivers/devfreq/exynos-bus.c
>  F:     Documentation/devicetree/bindings/devfreq/exynos-bus.txt
>
> +DMC FREQUENCY DRIVER FOR SAMSUNG EXYNOS5422
> +M:     Lukasz Luba <l.luba@partner.samsung.com>
> +L:     linux-pm@vger.kernel.org
> +L:     linux-samsung-soc@vger.kernel.org
> +S:     Maintained
> +F:     drivers/memory/samsung/exynos5422-dmc.c
> +F:     Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
> +
>  BUSLOGIC SCSI DRIVER
>  M:     Khalid Aziz <khalid@gonehiking.org>
>  L:     linux-scsi@vger.kernel.org
> diff --git a/drivers/memory/samsung/Kconfig b/drivers/memory/samsung/Kconfig
> index 79ce7ea..202972b 100644
> --- a/drivers/memory/samsung/Kconfig
> +++ b/drivers/memory/samsung/Kconfig
> @@ -5,6 +5,23 @@ config SAMSUNG_MC
>           Support for the Memory Controller (MC) devices found on
>           Samsung Exynos SoCs.
>
> +config ARM_EXYNOS5422_DMC
> +       tristate "ARM EXYNOS5422 Dynamic Memory Controller driver"
> +       depends on ARCH_EXYNOS || COMPILE_TEST
> +       select DDR
> +       select PM_DEVFREQ
> +       select DEVFREQ_GOV_SIMPLE_ONDEMAND
> +       select DEVFREQ_GOV_USERSPACE
> +       select PM_DEVFREQ_EVENT
> +       select PM_OPP
> +       help
> +         This adds driver for Exynos5422 DMC (Dynamic Memory Controller).
> +         The driver provides support for Dynamic Voltage and Frequency Scaling in
> +         DMC and DRAM. It also supports changing timings of DRAM running with
> +         different frequency. The timings are calculated based on DT memory
> +         information.
> +
> +
>  if SAMSUNG_MC
>
>  config EXYNOS_SROM
> diff --git a/drivers/memory/samsung/Makefile b/drivers/memory/samsung/Makefile
> index 00587be..4f6e438 100644
> --- a/drivers/memory/samsung/Makefile
> +++ b/drivers/memory/samsung/Makefile
> @@ -1,2 +1,3 @@
>  # SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_ARM_EXYNOS5422_DMC)       += exynos5422-dmc.o
>  obj-$(CONFIG_EXYNOS_SROM)      += exynos-srom.o
> diff --git a/drivers/memory/samsung/exynos5422-dmc.c b/drivers/memory/samsung/exynos5422-dmc.c
> new file mode 100644
> index 0000000..fa4cd4c
> --- /dev/null
> +++ b/drivers/memory/samsung/exynos5422-dmc.c
> @@ -0,0 +1,1793 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2019 Samsung Electronics Co., Ltd.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/debugfs.h>
> +#include <linux/delay.h>
> +#include <linux/devfreq.h>
> +#include <linux/devfreq-event.h>
> +#include <linux/device.h>
> +#include <linux/export.h>

Do you use it?

> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/pm_opp.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/seq_file.h>
> +#include <linux/slab.h>
> +#include <memory/jedec_ddr.h>
> +#include "../of_memory.h"
> +
> +#define EXYNOS5_DREXI_TIMINGAREF               (0x0030)
> +#define EXYNOS5_DREXI_TIMINGROW0               (0x0034)
> +#define EXYNOS5_DREXI_TIMINGDATA0              (0x0038)
> +#define EXYNOS5_DREXI_TIMINGPOWER0             (0x003C)
> +#define EXYNOS5_DREXI_TIMINGROW1               (0x00E4)
> +#define EXYNOS5_DREXI_TIMINGDATA1              (0x00E8)
> +#define EXYNOS5_DREXI_TIMINGPOWER1             (0x00EC)
> +#define CDREX_PAUSE                            (0x91c)
> +#define CDREX_LPDDR3PHY_CON3                   (0xa20)
> +#define EXYNOS5_TIMING_SET_SWI                  (1UL << 28)
> +#define USE_MX_MSPLL_TIMINGS                   (1)
> +#define USE_BPLL_TIMINGS                       (0)
> +
> +#define EXYNOS5_AREF_NORMAL                    (0x2e)
> +
> +#define IS_MEM_2GB(val) \
> +       (                                               \
> +        (((val) & 0xf0) & 0x20) ? 1 :                  \
> +               (((val) & 0xf0) & 0x30) ? 1 : 0         \
> +       )
> +
> +#define EXYNOS5_POP_OPTIONS(val)       (((val >> 4) & 0x3UL) << 4)
> +#define EXYNOS5_DDR_TYPE(val)          (((val >> 14) & 0x1UL))

I would prefer to split out this and code related to chipid to chipid
driver. Sylwester was adding similar parts for ASV so please unify it
consistently. IOW, if you need data from chipid I would prefer to get
it from chipid driver. This way we keep given feature only in one
driver - less code duplication, less logic spread all over, no need to
map the same region in multiple drivers.

> +
> +#define EXYNOS5_CHIP_PROD_ID           (0)
> +#define EXYNOS5_CHIP_PKG_ID            (4)
> +
> +#define PPMU_PMCNT_CONST_RATIO_MUL     15
> +#define PPMU_PMCNT_CONST_RATIO_DIV     10
> +
> +#define AXI_BUS_WIDTH_BYTES (128 >> 3)
> +
> +/**
> + * enum dmc_slot_id - An enum with slots in DMC

The comment copies the name so please remove it. Comment should bring
new information, not copy the source code.

> + */
> +enum dmc_slot_id {
> +       DMC0_0,
> +       DMC0_1,
> +       DMC1_0,
> +       DMC1_1,
> +       DMC_SLOTS_END
> +};
> +
> +/**
> + * struct dmc_slot_info - Describes DMC's slot
> + *
> + * The structure holds DMC's slot name which is part of the device name
> + * provided in DT. Each slot has particular share of the DMC bandwidth.
> + * To abstract the model performance and values in performance counters,
> + * fields 'ratio_mul' and 'ratio_div' are used in calculation algorithm
> + * for each slot. Please check the corresponding function with the algorithm,
> + * to see how these variables are used.
> + */
> +struct dmc_slot_info {
> +       char *name;
> +       int id;
> +       int ratio_mul;
> +       int ratio_div;
> +};
> +
> +/**
> + * struct dmc_opp_table - Operating level desciption
> + *
> + * Covers frequency and voltage settings of the DMC operating mode.
> + */
> +struct dmc_opp_table {
> +       u32 freq_hz;
> +       u32 volt_uv;
> +};
> +
> +/**
> + * struct exynos5_dmc - main structure describing DMC device
> + *
> + * The main structure for the Dynamic Memory Controller which covers clocks,
> + * memory regions, HW information, parameters and current operating mode.
> + */
> +struct exynos5_dmc {
> +       struct device *dev;
> +       struct devfreq *df;
> +       struct devfreq_simple_ondemand_data gov_data;
> +       void __iomem *base_drexi0;
> +       void __iomem *base_drexi1;
> +       void __iomem *chip_id;
> +       struct regmap *clk_regmap;
> +       struct mutex lock;
> +       unsigned long curr_rate;
> +       unsigned long curr_volt;
> +       unsigned long bypass_rate;
> +       struct dmc_opp_table *opp;
> +       struct dmc_opp_table opp_bypass;
> +       int opp_count;
> +       u32 timings_arr_size;
> +       u32 *timing_row;
> +       u32 *timing_data;
> +       u32 *timing_power;
> +       const struct lpddr3_timings *timings;
> +       const struct lpddr3_min_tck *min_tck;
> +       u32 bypass_timing_row;
> +       u32 bypass_timing_data;
> +       u32 bypass_timing_power;
> +       unsigned int prod_rev;
> +       unsigned int pkg_rev;
> +       unsigned int mem_info;
> +       struct regulator *vdd_mif;
> +       struct clk *fout_spll;
> +       struct clk *fout_bpll;
> +       struct clk *mout_spll;
> +       struct clk *mout_bpll;
> +       struct clk *mout_mclk_cdrex;
> +       struct clk *dout_clk2x_phy0;
> +       struct clk *mout_mx_mspll_ccore;
> +       struct clk *mx_mspll_ccore_phy;
> +       struct clk *mout_mx_mspll_ccore_phy;
> +       struct devfreq_event_dev **counter;
> +       int num_counters;
> +       bool counters_enabled;
> +#ifdef CONFIG_DEBUG_FS
> +       struct dentry *dbg_root;
> +#endif
> +};
> +
> +#define TIMING_FIELD(t_name, t_bit_beg, t_bit_end) \
> +       { .name = t_name, .bit_beg = t_bit_beg, .bit_end = t_bit_end }
> +
> +#define TIMING_VAL(timing_array, id, t_val)                    \
> +({                                                             \
> +               u32 __val;                              \
> +               __val = t_val << timing_array[id].bit_beg;      \
> +               __val;                                          \
> +})
> +
> +#define TIMING_VAL2REG(timing, t_val)                  \
> +({                                                             \
> +               u32 __val;                              \
> +               __val = t_val << timing->bit_beg;       \
> +               __val;                                          \
> +})
> +
> +#define TIMING_REG2VAL(reg, timing)                    \
> +({                                                             \
> +               u32 __val;                              \
> +               reg <<= (31 - timing->bit_end);         \
> +               reg >>= (31 - timing->bit_end);         \
> +               __val = reg >> timing->bit_beg; \
> +               __val;                                          \
> +})
> +
> +struct timing_reg {
> +       char *name;
> +       int bit_beg;
> +       int bit_end;
> +       unsigned int val;
> +};
> +
> +static struct timing_reg timing_row[] = {
> +       TIMING_FIELD("tRFC", 24, 31),
> +       TIMING_FIELD("tRRD", 20, 23),
> +       TIMING_FIELD("tRP", 16, 19),
> +       TIMING_FIELD("tRCD", 12, 15),
> +       TIMING_FIELD("tRC", 6, 11),
> +       TIMING_FIELD("tRAS", 0, 5),
> +};
> +
> +static struct timing_reg timing_data[] = {
> +       TIMING_FIELD("tWTR", 28, 31),
> +       TIMING_FIELD("tWR", 24, 27),
> +       TIMING_FIELD("tRTP", 20, 23),
> +       TIMING_FIELD("tW2W-C2C", 14, 14),
> +       TIMING_FIELD("tR2R-C2C", 12, 12),
> +       TIMING_FIELD("WL", 8, 11),
> +       TIMING_FIELD("tDQSCK", 4, 7),
> +       TIMING_FIELD("RL", 0, 3),
> +};
> +
> +static struct timing_reg timing_power[] = {

All these looks like const. At least I could not see any writes to them.

> +       TIMING_FIELD("tFAW", 26, 31),
> +       TIMING_FIELD("tXSR", 16, 25),
> +       TIMING_FIELD("tXP", 8, 15),
> +       TIMING_FIELD("tCKE", 4, 7),
> +       TIMING_FIELD("tMRD", 0, 3),
> +};
> +
> +#define TIMING_COUNT (ARRAY_SIZE(timing_row) + ARRAY_SIZE(timing_data) + \
> +                     ARRAY_SIZE(timing_power))
> +
> +/**
> + * exynos5_counters_fname() - Macro generating function for event devices
> + * @f:         function name suffix
> + *
> + * Macro which generates needed function for manipulation of event devices.
> + * It aims to avoid code duplication relaying on similar prefix and function
> + * parameters in the devfreq event device framework functions.
> + */
> +#define exynos5_counters_fname(f)                              \
> +static int exynos5_counters_##f(struct exynos5_dmc *dmc)       \
> +{                                                              \
> +       int i, ret;                                             \
> +                                                               \
> +       for (i = 0; i < dmc->num_counters; i++) {               \
> +               if (!dmc->counter[i])                           \
> +                       continue;                               \
> +               ret = devfreq_event_##f(dmc->counter[i]);       \
> +               if (ret < 0)                                    \
> +                       return ret;                             \
> +       }                                                       \
> +       return 0;                                               \
> +}
> +
> +/* Declarations for the function generated by the macro above. */
> +static int exynos5_counters_set_event(struct exynos5_dmc *dmc);
> +static int exynos5_counters_enable_edev(struct exynos5_dmc *dmc);
> +static int exynos5_counters_disable_edev(struct exynos5_dmc *dmc);

You save some lines of code but make it more difficult to follow and
understand. I do not think it is worth the effort especially that
duplicated code is not difficult... so I prefer duplication than
obfuscation in such case. Define regular functions.

> +
> +/* Generate needed functions for managing event device. */
> +exynos5_counters_fname(set_event);
> +exynos5_counters_fname(enable_edev);
> +exynos5_counters_fname(disable_edev);
> +
> +/* Event names to DMC channel and slot with proper data count type */
> +static const char *event_name[] = {
> +       /* Counters for DMC0 slot 0 */
> +       "ppmu-event0-dmc0_0",
> +       "DMC0_0-Read",
> +       "ppmu-event1-dmc0_0",
> +       "DMC0_0-Write",
> +       "ppmu-event3-dmc0_0",
> +       "DMC0_0-Read+Write",
> +       /* Counters for DMC0 slot 1 */
> +       "ppmu-event0-dmc0_1",
> +       "DMC0_1-Read",
> +       "ppmu-event1-dmc0_1",
> +       "DMC0_1-Write",
> +       "ppmu-event3-dmc0_1",
> +       "DMC0_1-Read+Write",
> +       /* Counters for DMC1 slot 0 */
> +       "ppmu-event0-dmc1_0",
> +       "DMC1_0-Read",
> +       "ppmu-event1-dmc1_0",
> +       "DMC1_0-Write",
> +       "ppmu-event3-dmc1_0",
> +       "DMC1_0-Read+Write",
> +       /* Counters for DMC1 slot 0 */
> +       "ppmu-event0-dmc1_1",
> +       "DMC1_1-Read",
> +       "ppmu-event1-dmc1_1",
> +       "DMC1_1-Write",
> +       "ppmu-event3-dmc1_1",
> +       "DMC1_1-Read+Write",
> +};
> +
> +/**
> + * find_target_freq_id() - Finds requested frequency in local DMC configuration
> + * @dmc:       device for which the information is checked
> + * @target_rate:       requested frequency in KHz
> + *
> + * Seeks in the local DMC driver structure for the requested frequency value
> + * and returns index or error value.
> + */
> +static int find_target_freq_idx(struct exynos5_dmc *dmc,
> +                               unsigned long target_rate)
> +{
> +       int i;
> +
> +       for (i = dmc->opp_count - 1; i >= 0; i--)
> +               if (dmc->opp[i].freq_hz <= target_rate)
> +                       return i;
> +
> +       return -EINVAL;
> +}
> +
> +/**
> + * exynos5_dmc_chip_revision_settings() - Chooses proper DMC's configuration
> + * @dmc:       device for which is going to be checked and configured
> + *
> + * Function checks the HW product information in order to choose proper
> + * configuration for DMC frequency, voltage and DRAM timings.
> + */
> +static int exynos5_dmc_chip_revision_settings(struct exynos5_dmc *dmc)
> +{
> +       unsigned int val;
> +
> +       val = readl(dmc->chip_id + EXYNOS5_CHIP_PROD_ID);
> +       dmc->prod_rev = val;
> +
> +       val = readl(dmc->chip_id + EXYNOS5_CHIP_PKG_ID);
> +       dmc->pkg_rev = val;
> +
> +       dmc->mem_info = EXYNOS5_POP_OPTIONS(val);
> +       dmc->mem_info |= EXYNOS5_DDR_TYPE(val);
> +
> +       if (!IS_MEM_2GB(dmc->mem_info)) {
> +               dev_warn(dmc->dev, "DRAM memory type not supported\n");
> +               return -EINVAL;
> +       }
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_switch_timing_regs() - Changes bank register set for DRAM timings
> + * @dmc:       device for which the new settings is going to be applied
> + * @set:       boolean variable passing set value
> + *
> + * Changes the register set, which holds timing parameters.
> + * There is two register sets: 0 and 1. The register set 0
> + * is used in normal operation when the clock is provided from main PLL.
> + * The bank register set 1 is used when the main PLL frequency is going to be
> + * changed and the clock is taken from alternative, stable source.
> + * This function switches between these banks according to the
> + * currently used clock source.
> + */
> +static void exynos5_switch_timing_regs(struct exynos5_dmc *dmc, bool set)
> +{
> +       unsigned int reg;
> +       int ret;
> +
> +       ret = regmap_read(dmc->clk_regmap, CDREX_LPDDR3PHY_CON3, &reg);
> +
> +       if (set)
> +               reg |= EXYNOS5_TIMING_SET_SWI;
> +       else
> +               reg &= ~EXYNOS5_TIMING_SET_SWI;
> +
> +       regmap_write(dmc->clk_regmap, CDREX_LPDDR3PHY_CON3, reg);
> +}
> +
> +/**
> + * exynos5_init_freq_table() - Initialized PM OPP framework
> + * @dev:       devfreq device for which the OPP table is going to be
> + *             initialized
> + * @dmc:       DMC device for which the frequencies are used for OPP init
> + * @profile:   devfreq device's profile
> + *
> + * Populate the devfreq device's OPP table based on current frequency, voltage.
> + */
> +static int exynos5_init_freq_table(struct device *dev, struct exynos5_dmc *dmc,
> +                                  struct devfreq_dev_profile *profile)
> +{
> +       int i, ret;
> +       int idx;
> +       unsigned long freq;
> +
> +       ret = dev_pm_opp_of_add_table(dev);
> +       if (ret < 0) {
> +               dev_err(dev, "Failed to get OPP table\n");
> +               return ret;
> +       }
> +
> +       dmc->opp_count = dev_pm_opp_get_opp_count(dev);
> +
> +       dmc->opp = devm_kmalloc_array(dmc->dev, dmc->opp_count,
> +                                     sizeof(struct dmc_opp_table), GFP_KERNEL);
> +       if (!dmc->opp)
> +               goto err_opp;
> +
> +       idx = dmc->opp_count - 1;
> +       for (i = 0, freq = ULONG_MAX; i < dmc->opp_count; i++, freq--) {
> +               struct dev_pm_opp *opp;
> +
> +               opp = dev_pm_opp_find_freq_floor(dev, &freq);
> +               if (IS_ERR(opp))
> +                       goto err_free_tables;
> +
> +               dmc->opp[idx - i].freq_hz = freq;
> +               dmc->opp[idx - i].volt_uv = dev_pm_opp_get_voltage(opp);
> +
> +               dev_pm_opp_put(opp);
> +       }
> +
> +       return 0;
> +
> +err_free_tables:
> +       kfree(dmc->opp);
> +err_opp:
> +       dev_pm_opp_of_remove_table(dev);
> +
> +       return -EINVAL;
> +}
> +
> +/**
> + * exynos5_set_bypass_dram_timings() - Low-level changes of the DRAM timings
> + * @dmc:       device for which the new settings is going to be applied
> + * @param:     DRAM parameters which passes timing data
> + *
> + * Low-level function for changing timings for DRAM memory clocking from
> + * 'bypass' clock source (fixed frequency @400MHz).
> + * It uses timing bank registers set 1.
> + */
> +static void exynos5_set_bypass_dram_timings(struct exynos5_dmc *dmc)
> +{
> +       writel(EXYNOS5_AREF_NORMAL,
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
> +
> +       writel(dmc->bypass_timing_row,
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW1);
> +       writel(dmc->bypass_timing_row,
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW1);
> +       writel(dmc->bypass_timing_data,
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA1);
> +       writel(dmc->bypass_timing_data,
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA1);
> +       writel(dmc->bypass_timing_power,
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER1);
> +       writel(dmc->bypass_timing_power,
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER1);
> +}
> +
> +/**
> + * exynos5_dram_change_timings() - Low-level changes of the DRAM final timings
> + * @dmc:       device for which the new settings is going to be applied
> + * @target_rate:       target frequency of the DMC
> + *
> + * Low-level function for changing timings for DRAM memory operating from main
> + * clock source (BPLL), which can have different frequencies. Thus, each
> + * frequency must have corresponding timings register values in order to keep
> + * the needed delays.
> + * It uses timing bank registers set 0.
> + */
> +static int exynos5_dram_change_timings(struct exynos5_dmc *dmc,
> +                                      unsigned long target_rate)
> +{
> +       int idx;
> +
> +       for (idx = dmc->opp_count - 1; idx >= 0; idx--)
> +               if (dmc->opp[idx].freq_hz <= target_rate)
> +                       break;
> +
> +       if (idx < 0)
> +               return -EINVAL;
> +
> +       writel(EXYNOS5_AREF_NORMAL,
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
> +
> +       writel(dmc->timing_row[idx],
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW0);
> +       writel(dmc->timing_row[idx],
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW0);
> +       writel(dmc->timing_data[idx],
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA0);
> +       writel(dmc->timing_data[idx],
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA0);
> +       writel(dmc->timing_power[idx],
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER0);
> +       writel(dmc->timing_power[idx],
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER0);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_align_target_voltage() - Sets the final voltage for the DMC
> + * @dmc:       device for which it is going to be set
> + * @target_volt:       new voltage which is chosen to be final
> + *
> + * Function tries to align voltage to the safe level for 'normal' mode.
> + * It checks the need of higher voltage and changes the value. The target
> + * voltage might be lower that currently set and still the system will be
> + * stable.
> + */
> +static int exynos5_dmc_align_target_voltage(struct exynos5_dmc *dmc,
> +                                           unsigned long target_volt)
> +{
> +       int ret = 0;
> +
> +       if (dmc->curr_volt > target_volt) {
> +               ret = regulator_set_voltage(dmc->vdd_mif, target_volt,
> +                                           target_volt);
> +               if (!ret)
> +                       dmc->curr_volt = target_volt;
> +       }
> +
> +       return ret;
> +}
> +
> +/**
> + * exynos5_dmc_align_bypass_voltage() - Sets the voltage for the DMC
> + * @dmc:       device for which it is going to be set
> + * @target_volt:       new voltage which is chosen to be final
> + *
> + * Function tries to align voltage to the safe level for the 'bypass' mode.
> + * It checks the need of higher voltage and changes the value.
> + * The target voltage must not be less than currently needed, because
> + * for current frequency the device might become unstable.
> + */
> +static int exynos5_dmc_align_bypass_voltage(struct exynos5_dmc *dmc,
> +                                           unsigned long target_volt)
> +{
> +       int ret = 0;
> +       unsigned long bypass_volt = dmc->opp_bypass.volt_uv;
> +
> +       target_volt = max(bypass_volt, target_volt);
> +
> +       if (dmc->curr_volt >= target_volt)
> +               return 0;
> +
> +       ret = regulator_set_voltage(dmc->vdd_mif, target_volt,
> +                                   target_volt);
> +       if (!ret)
> +               dmc->curr_volt = target_volt;
> +
> +       return ret;
> +}
> +
> +/**
> + * exynos5_dmc_align_bypass_dram_timings() - Chooses and sets DRAM timings
> + * @dmc:       device for which it is going to be set
> + * @target_rate:       new frequency which is chosen to be final
> + *
> + * Function changes the DRAM timings for the temporary 'bypass' mode.
> + */
> +static int exynos5_dmc_align_bypass_dram_timings(struct exynos5_dmc *dmc,
> +                                                unsigned long target_rate)
> +{
> +       int idx = find_target_freq_idx(dmc, target_rate);
> +
> +       if (idx < 0)
> +               return -EINVAL;
> +
> +       exynos5_set_bypass_dram_timings(dmc);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_switch_to_bypass_configuration() - Switching to temporary clock
> + * @dmc:       DMC device for which the switching is going to happen
> + * @target_rate:       new frequency which is going to be set as a final
> + * @target_volt:       new voltage which is going to be set as a final
> + *
> + * Function configures DMC and clocks for operating in temporary 'bypass' mode.
> + * This mode is used only temporary but if required, changes voltage and timings
> + * for DRAM chips. It switches the main clock to stable clock source for the
> + * period of the main PLL reconfiguration.
> + */
> +static int exynos5_dmc_switch_to_bypass_configuration(struct exynos5_dmc *dmc,
> +                                  unsigned long target_rate,
> +                                  unsigned long target_volt)
> +{
> +       int ret;
> +
> +       /*
> +        * Having higher voltage for a particular frequency does not harm
> +        * the chip. Use it for the temporary frequency change when one
> +        * voltage manipulation might be avoided.
> +        */
> +       ret = exynos5_dmc_align_bypass_voltage(dmc, target_volt);
> +       if (ret)
> +               return ret;
> +
> +       /*
> +        * Longer delays for DRAM does not cause crash, the opposite does.
> +        */
> +       ret = exynos5_dmc_align_bypass_dram_timings(dmc, target_rate);
> +       if (ret)
> +               return ret;
> +
> +       /*
> +        * Delays are long enough, so use them for the new coming clock.
> +        */
> +       exynos5_switch_timing_regs(dmc, USE_MX_MSPLL_TIMINGS);
> +
> +       /*
> +        * Voltage is set at least to a level needed for this frequency,
> +        * so switching clock source is safe now.
> +        */
> +       clk_prepare_enable(dmc->fout_spll);
> +       clk_prepare_enable(dmc->mout_spll);
> +       clk_prepare_enable(dmc->mout_mx_mspll_ccore);

Move the clock handling to the same function when you disable them. It
makes it easy to review whether you have unbalanced enable/disable.

> +
> +       ret = clk_set_parent(dmc->mout_mclk_cdrex, dmc->mout_mx_mspll_ccore);
> +
> +       return ret;
> +}
> +
> +/**
> + * exynos5_dmc_change_freq_and_volt() - Changes voltage and frequency of the DMC
> + * using safe procedure
> + * @dmc:       device for which the frequency is going to be changed
> + * @target_rate:       requested new frequency
> + * @target_volt:       requested voltage which corresponds to the new frequency
> + *
> + * The DMC frequency change procedure requires a few steps.
> + * The main requirement is to change the clock source in the clk mux
> + * for the time of main clock PLL locking. The assumption is that the
> + * alternative clock source set as parent is stable.
> + * The second parent's clock frequency is fixed to 400MHz, it is named 'bypass'
> + * clock. This requires alignment in DRAM timing parameters for the new
> + * T-period. There is two bank sets for keeping DRAM
> + * timings: set 0 and set 1. The set 0 is used when main clock source is
> + * chosen. The 2nd set of regs is used for 'bypass' clock. Switching between
> + * the two bank sets is part of the process.
> + * The voltage must also be aligned to the minimum required level. There is
> + * this intermediate step with switching to 'bypass' parent clock source.
> + * if the old voltage is lower, it requires an increase of the voltage level.
> + * The complexity of the voltage manipulation is hidden in low level function.
> + * In this function there is last alignment of the voltage level at the end.
> + */
> +static int
> +exynos5_dmc_change_freq_and_volt(struct exynos5_dmc *dmc,
> +                                unsigned long target_rate,
> +                                unsigned long target_volt)
> +{
> +       int ret;
> +
> +       ret = exynos5_dmc_switch_to_bypass_configuration(dmc, target_rate,
> +                                                        target_volt);
> +       if (ret)
> +               return ret;
> +
> +       /* We are safe to increase the timings for current bypass frequency.

Start with /* alone.

> +        * Thanks to this the settings we be ready for the upcoming clock source
> +        * change.
> +        */
> +       exynos5_dram_change_timings(dmc, target_rate);
> +
> +       clk_set_rate(dmc->fout_bpll, target_rate);
> +
> +       exynos5_switch_timing_regs(dmc, USE_BPLL_TIMINGS);
> +
> +       ret = clk_set_parent(dmc->mout_mclk_cdrex, dmc->mout_bpll);
> +       if (ret)
> +               return ret;
> +
> +       clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
> +       clk_disable_unprepare(dmc->mout_spll);
> +       clk_disable_unprepare(dmc->fout_spll);
> +       /* Make sure if the voltage is not from 'bypass' settings and align to
> +        * the right level for power efficiency.
> +        */
> +       ret = exynos5_dmc_align_target_voltage(dmc, target_volt);
> +
> +       return ret;
> +}
> +
> +/**
> + * exynos5_dmc_get_volt_freq() - Gets the frequency and voltage from the OPP
> + * table.
> + * @dev:       device for which the frequency is going to be changed
> + * @freq:       requested frequency in KHz
> + * @target_rate:       returned frequency which is the same or lower than
> + *                     requested
> + * @target_volt:       returned voltage which corresponds to the returned
> + *                     frequency
> + *
> + * Function gets requested frequency and checks OPP framework for needed
> + * frequency and voltage. It populates the values 'target_rate' and
> + * 'target_volt' or returns error value when OPP framework fails.
> + */
> +static int exynos5_dmc_get_volt_freq(struct device *dev, unsigned long *freq,
> +                                    unsigned long *target_rate,
> +                                    unsigned long *target_volt, u32 flags)
> +{
> +       struct dev_pm_opp *opp;
> +
> +       opp = devfreq_recommended_opp(dev, freq, flags);
> +       if (IS_ERR(opp))
> +               return PTR_ERR(opp);
> +
> +       *target_rate = dev_pm_opp_get_freq(opp);
> +       *target_volt = dev_pm_opp_get_voltage(opp);
> +       dev_pm_opp_put(opp);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_target() - Function responsible for changing frequency of DMC
> + * @dev:       device for which the frequency is going to be changed
> + * @freq:      requested frequency in KHz
> + * @flags:     flags provided for this frequency change request
> + *
> + * An entry function provided to the devfreq framework which provides frequency
> + * change of the DMC. The function gets the possible rate from OPP table based
> + * on requested frequency. It calls the next function responsible for the
> + * frequency and voltage change. In case of failure, does not set 'curr_rate'
> + * and returns error value to the framework.
> + */
> +static int exynos5_dmc_target(struct device *dev, unsigned long *freq,
> +                             u32 flags)
> +{
> +       struct exynos5_dmc *dmc = dev_get_drvdata(dev);
> +       unsigned long target_rate = 0;
> +       unsigned long target_volt = 0;
> +       int ret;
> +
> +       ret = exynos5_dmc_get_volt_freq(dev, freq, &target_rate, &target_volt,
> +                                       flags);
> +
> +       if (ret)
> +               return ret;
> +
> +       if (target_rate == dmc->curr_rate)
> +               return 0;
> +
> +       mutex_lock(&dmc->lock);
> +
> +       ret = exynos5_dmc_change_freq_and_volt(dmc, target_rate, target_volt);
> +
> +       if (ret) {
> +               mutex_unlock(&dmc->lock);
> +               return ret;
> +       }
> +
> +       dmc->curr_rate = target_rate;
> +
> +       mutex_unlock(&dmc->lock);
> +       return 0;
> +}
> +
> +/**
> + * exynos5_counters_get() - Gets the performance counters values.
> + * @dmc:       device for which the counters are going to be checked
> + * @load_count:        variable which is populated with counter value
> + * @total_count:       variable which is used as 'wall clock' reference
> + *
> + * Function which provides performance counters values. It sums up counters for
> + * two DMC channels. The 'total_count' is used as a reference and max value.
> + * The ratio 'load_count/total_count' shows the busy percentage [0%, 100%].
> + */
> +static int exynos5_counters_get(struct exynos5_dmc *dmc,
> +                               unsigned long *load_count,
> +                               unsigned long *total_count)
> +{
> +       unsigned long total = 0;
> +       struct devfreq_event_data event;
> +       int ret, i;
> +
> +       *load_count = 0;
> +
> +       /* Take into account only read+write counters, but stop all */
> +       for (i = 0; i < dmc->num_counters; i++) {
> +               if (!dmc->counter[i])
> +                       continue;
> +
> +               ret = devfreq_event_get_event(dmc->counter[i], &event);
> +               if (ret < 0)
> +                       return ret;
> +
> +               if (i % 3 != 2)
> +                       continue;
> +
> +               *load_count += event.load_count;
> +
> +               if (total < event.total_count)
> +                       total = event.total_count;
> +       }
> +
> +       *total_count = total;
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_get_status() - Read current DMC performance statistics.
> + * @dev:       device for which the statistics are requested
> + * @stat:      structure which has statistic fields
> + *
> + * Function reads the DMC performance counters and calculates 'busy_time'
> + * and 'total_time'. To protect from overflow, the values are shifted right
> + * by 10. After read out the counters are setup to count again.
> + */
> +static int exynos5_dmc_get_status(struct device *dev,
> +                                 struct devfreq_dev_status *stat)
> +{
> +       struct exynos5_dmc *dmc = dev_get_drvdata(dev);
> +       unsigned long load, total;
> +       int ret;
> +       bool cnt_en;
> +
> +       mutex_lock(&dmc->lock);
> +       cnt_en = dmc->counters_enabled;
> +       mutex_unlock(&dmc->lock);
> +       if (!cnt_en) {
> +               dev_warn(dev, "performance counters needed, but not present\n");
> +               return -EAGAIN;
> +       }
> +
> +       ret = exynos5_counters_get(dmc, &load, &total);
> +       if (ret < 0)
> +               return -EINVAL;
> +
> +       /* To protect from overflow in calculation ratios, divide by 1024 */
> +       stat->busy_time = load >> 10;
> +       stat->total_time = total >> 10;
> +
> +       ret = exynos5_counters_set_event(dmc);
> +       if (ret < 0) {
> +               dev_err(dmc->dev, "could not set event counter\n");
> +               return ret;
> +       }
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_get_cur_freq() - Function returns current DMC frequency
> + * @dev:       device for which the framework checks operating frequency
> + * @freq:      returned frequency value
> + *
> + * It returns the currently used frequency of the DMC. The real operating
> + * frequency might be lower when the clock source value could not be divided
> + * to the requested value.
> + */
> +static int exynos5_dmc_get_cur_freq(struct device *dev, unsigned long *freq)
> +{
> +       struct exynos5_dmc *dmc = dev_get_drvdata(dev);
> +
> +       mutex_lock(&dmc->lock);
> +       *freq = dmc->curr_rate;
> +       mutex_unlock(&dmc->lock);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_df_profile - Devfreq governor's profile structure
> + *
> + * It provides to the devfreq framework needed functions and polling period.
> + */
> +static struct devfreq_dev_profile exynos5_dmc_df_profile = {
> +       .polling_ms = 500,
> +       .target = exynos5_dmc_target,
> +       .get_dev_status = exynos5_dmc_get_status,
> +       .get_cur_freq = exynos5_dmc_get_cur_freq,
> +};
> +
> +/**
> + * exynos5_dmc_align_initial_frequency() - Align initial frequency value
> + * @dmc:       device for which the frequency is going to be set
> + * @bootloader_init_freq:      initial frequency set by the bootloader in KHz
> + *
> + * The initial bootloader frequency, which is present during boot, might be
> + * different that supported frequency values in the driver. It is possible
> + * due to different PLL settings or used PLL as a source.
> + * This function provides the 'initial_freq' for the devfreq framework
> + * statistics engine which supports only registered values. Thus, some alignment
> + * must be made.
> + */
> +unsigned long
> +exynos5_dmc_align_init_freq(struct exynos5_dmc *dmc,
> +                           unsigned long bootloader_init_freq)
> +{
> +       unsigned long aligned_freq;
> +       int idx;
> +
> +       idx = find_target_freq_idx(dmc, bootloader_init_freq);
> +       if (idx >= 0)
> +               aligned_freq = dmc->opp[idx].freq_hz;
> +       else
> +               aligned_freq = dmc->opp[dmc->opp_count - 1].freq_hz;
> +
> +       return aligned_freq;
> +}
> +
> +/**
> + * create_timings_aligned() - Create register values and align with standard
> + * @dmc:       device for which the frequency is going to be set
> + * @idx:       speed bin in the OPP table
> + * @clk_period_ps:     the period of the clock, known as tCK
> + *
> + * The function calculates timings and creates a register value ready for
> + * a frequency transition. The register contains a few timings. They are
> + * shifted by a known offset. The timing value is calculated based on memory
> + * specyfication: minimal time required and minimal cycles required.
> + */
> +static int create_timings_aligned(struct exynos5_dmc *dmc, u32 *reg_timing_row,
> +                                 u32 *reg_timing_data, u32 *reg_timing_power,
> +                                 u32 clk_period_ps)
> +{
> +       u32 val;
> +       struct timing_reg *reg;
> +
> +       if (clk_period_ps == 0)
> +               return -EINVAL;
> +
> +       *reg_timing_row = 0;
> +       *reg_timing_data = 0;
> +       *reg_timing_power = 0;
> +
> +       val = dmc->timings->tRFC / clk_period_ps;
> +       val += dmc->timings->tRFC % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tRFC);
> +       reg = &timing_row[0];
> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tRRD / clk_period_ps;
> +       val += dmc->timings->tRRD % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tRRD);
> +       reg = &timing_row[1];
> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tRPab / clk_period_ps;
> +       val += dmc->timings->tRPab % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tRPab);
> +       reg = &timing_row[2];
> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tRCD / clk_period_ps;
> +       val += dmc->timings->tRCD % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tRCD);
> +       reg = &timing_row[3];
> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tRC / clk_period_ps;
> +       val += dmc->timings->tRC % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tRC);
> +       reg = &timing_row[4];
> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tRAS / clk_period_ps;
> +       val += dmc->timings->tRAS % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tRAS);
> +       reg = &timing_row[5];
> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
> +
> +       /* data related timings */
> +       val = dmc->timings->tWTR / clk_period_ps;
> +       val += dmc->timings->tWTR % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tWTR);
> +       reg = &timing_data[0];
> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tWR / clk_period_ps;
> +       val += dmc->timings->tWR % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tWR);
> +       reg = &timing_data[1];
> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tRTP / clk_period_ps;
> +       val += dmc->timings->tRTP % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tRTP);
> +       reg = &timing_data[2];
> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tW2W_C2C / clk_period_ps;
> +       val += dmc->timings->tW2W_C2C % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tW2W_C2C);
> +       reg = &timing_data[3];
> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tR2R_C2C / clk_period_ps;
> +       val += dmc->timings->tR2R_C2C % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tR2R_C2C);
> +       reg = &timing_data[4];
> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tWL / clk_period_ps;
> +       val += dmc->timings->tWL % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tWL);
> +       reg = &timing_data[5];
> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tDQSCK / clk_period_ps;
> +       val += dmc->timings->tDQSCK % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tDQSCK);
> +       reg = &timing_data[6];
> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tRL / clk_period_ps;
> +       val += dmc->timings->tRL % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tRL);
> +       reg = &timing_data[7];
> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
> +
> +       /* power related timings */
> +       val = dmc->timings->tFAW / clk_period_ps;
> +       val += dmc->timings->tFAW % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tXP);
> +       reg = &timing_power[0];
> +       *reg_timing_power |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tXSR / clk_period_ps;
> +       val += dmc->timings->tXSR % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tXSR);
> +       reg = &timing_power[1];
> +       *reg_timing_power |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tXP / clk_period_ps;
> +       val += dmc->timings->tXP % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tXP);
> +       reg = &timing_power[2];
> +       *reg_timing_power |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tCKE / clk_period_ps;
> +       val += dmc->timings->tCKE % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tCKE);
> +       reg = &timing_power[3];
> +       *reg_timing_power |= TIMING_VAL2REG(reg, val);
> +
> +       val = dmc->timings->tMRD / clk_period_ps;
> +       val += dmc->timings->tMRD % clk_period_ps ? 1 : 0;
> +       val = max(val, dmc->min_tck->tMRD);
> +       reg = &timing_power[4];
> +       *reg_timing_power |= TIMING_VAL2REG(reg, val);
> +
> +       return 0;
> +}
> +
> +/**
> + * of_get_dram_timings() - helper function for parsing DT settings for DRAM
> + * @dmc:        device for which the frequency is going to be set
> + *
> + * The function parses DT entries with DRAM information.
> + */
> +static int of_get_dram_timings(struct exynos5_dmc *dmc)
> +{
> +       int ret = 0;
> +       struct device_node *np;
> +       int idx;
> +       struct device_node *np_ddr;

Combine with previous definition.

> +       u32 freq_mhz, clk_period_ps;
> +
> +       np_ddr = of_parse_phandle(dmc->dev->of_node, "device-handle", 0);
> +       if (!np_ddr) {
> +               dev_warn(dmc->dev, "could not find 'device-handle' in DT\n");
> +               return -EINVAL;
> +       }
> +
> +       dmc->timing_row = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
> +                                            sizeof(u32), GFP_KERNEL);
> +       if (!dmc->timing_row)
> +               return -ENOMEM;
> +
> +       dmc->timing_data = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
> +                                             sizeof(u32), GFP_KERNEL);
> +       if (!dmc->timing_data)
> +               return -ENOMEM;
> +
> +       dmc->timing_power = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
> +                                              sizeof(u32), GFP_KERNEL);
> +       if (!dmc->timing_power)
> +               return -ENOMEM;
> +
> +       dmc->timings = of_lpddr3_get_ddr_timings(np_ddr, dmc->dev,
> +                                                DDR_TYPE_LPDDR3,
> +                                                &dmc->timings_arr_size);
> +       if (!dmc->timings) {
> +               of_node_put(np_ddr);
> +               dev_warn(dmc->dev, "could not get timings from DT\n");
> +               return -EINVAL;
> +       }
> +
> +       dmc->min_tck = of_lpddr3_get_min_tck(np_ddr, dmc->dev);
> +       if (!dmc->min_tck) {
> +               of_node_put(np_ddr);
> +               dev_warn(dmc->dev, "could not get tck from DT\n");
> +               return -EINVAL;
> +       }
> +
> +       /* Sorted array of OPPs with frequency ascending */
> +       for (idx = 0; idx < dmc->opp_count; idx++) {
> +               freq_mhz = dmc->opp[idx].freq_hz / 1000000;
> +               clk_period_ps = 1000000 / freq_mhz;
> +
> +               ret = create_timings_aligned(dmc, &dmc->timing_row[idx],
> +                                            &dmc->timing_data[idx],
> +                                            &dmc->timing_power[idx],
> +                                            clk_period_ps);
> +       }
> +
> +       of_node_put(np);

This looks weird. You do not assign np... or I missed something.

> +
> +       /* Take the highest frequency's timings as 'bypass' */
> +       dmc->bypass_timing_row = dmc->timing_row[idx - 1];
> +       dmc->bypass_timing_data = dmc->timing_data[idx - 1];
> +       dmc->bypass_timing_power = dmc->timing_power[idx - 1];
> +
> +       return ret;
> +}
> +
> +/**
> + * exynos5_dmc_init_clks() - Initialize clocks needed for DMC operation.
> + * @dev:       device for which the clocks are setup
> + * @dmc:       DMC structure containing needed fields
> + *
> + * Get the needed clocks defined in DT device, enable and set the right parents.
> + * Read current frequency and initialize the initial rate for governor.
> + */
> +static int exynos5_dmc_init_clks(struct device *dev, struct exynos5_dmc *dmc)
> +{
> +       int ret;
> +       unsigned long target_volt = 0;
> +       unsigned long target_rate = 0;
> +
> +       dmc->fout_spll = devm_clk_get(dev, "fout_spll");
> +       if (IS_ERR(dmc->fout_spll))
> +               return PTR_ERR(dmc->fout_spll);
> +
> +       dmc->fout_bpll = devm_clk_get(dev, "fout_bpll");
> +       if (IS_ERR(dmc->fout_bpll))
> +               return PTR_ERR(dmc->fout_bpll);
> +
> +       dmc->mout_mclk_cdrex = devm_clk_get(dev, "mout_mclk_cdrex");
> +       if (IS_ERR(dmc->mout_mclk_cdrex))
> +               return PTR_ERR(dmc->mout_mclk_cdrex);
> +
> +       dmc->mout_bpll = devm_clk_get(dev, "mout_bpll");
> +       if (IS_ERR(dmc->mout_bpll))
> +               return PTR_ERR(dmc->mout_bpll);
> +
> +       dmc->mout_mx_mspll_ccore = devm_clk_get(dev, "mout_mx_mspll_ccore");
> +       if (IS_ERR(dmc->mout_mx_mspll_ccore))
> +               return PTR_ERR(dmc->mout_mx_mspll_ccore);
> +
> +       dmc->dout_clk2x_phy0 = devm_clk_get(dev, "dout_clk2x_phy0");
> +       if (IS_ERR(dmc->dout_clk2x_phy0))
> +               return PTR_ERR(dmc->dout_clk2x_phy0);
> +
> +       dmc->mout_spll = devm_clk_get(dev, "ff_dout_spll2");
> +       if (IS_ERR(dmc->mout_spll)) {
> +               dmc->mout_spll = devm_clk_get(dev, "mout_sclk_spll");
> +               if (IS_ERR(dmc->mout_spll))
> +                       return PTR_ERR(dmc->mout_spll);
> +       }
> +
> +       /*
> +        * Convert frequency to KHz values and set it for the governor.
> +        */
> +       dmc->curr_rate = clk_get_rate(dmc->mout_mclk_cdrex);
> +       dmc->curr_rate = exynos5_dmc_align_init_freq(dmc, dmc->curr_rate);
> +       exynos5_dmc_df_profile.initial_freq = dmc->curr_rate;
> +
> +       ret = exynos5_dmc_get_volt_freq(dev, &dmc->curr_rate, &target_rate,
> +                                       &target_volt, 0);
> +       if (ret)
> +               return ret;
> +
> +       dmc->curr_volt = target_volt;
> +
> +       clk_prepare_enable(dmc->mout_spll);
> +       clk_set_parent(dmc->mout_mx_mspll_ccore, dmc->mout_spll);
> +       clk_prepare_enable(dmc->mout_mx_mspll_ccore);
> +
> +       dmc->bypass_rate = clk_get_rate(dmc->mout_mx_mspll_ccore);
> +
> +       clk_prepare_enable(dmc->fout_bpll);
> +       clk_prepare_enable(dmc->mout_bpll);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_performance_counters_init() - Initializes performance DMC's counters
> + * @dmc:       DMC for which it does the setup
> + *
> + * Initialization of performance counters in DMC for estimating usage.
> + * The counter's values are used for calculation of a memory bandwidth and based
> + * on that the governor changes the frequency.
> + * The counters are not used when the governor is GOVERNOR_USERSPACE.
> + */
> +static int exynos5_performance_counters_init(struct exynos5_dmc *dmc)
> +{
> +       int counters_size;
> +       int ret, i;
> +
> +       dmc->num_counters = devfreq_event_get_edev_count(dmc->dev);
> +       if (dmc->num_counters < 0) {
> +               dev_err(dmc->dev, "could not get devfreq-event counters\n");
> +               return dmc->num_counters;
> +       }
> +
> +       counters_size = sizeof(struct devfreq_event_dev) * dmc->num_counters;
> +       dmc->counter = devm_kzalloc(dmc->dev, counters_size, GFP_KERNEL);
> +       if (!dmc->counter)
> +               return -ENOMEM;
> +
> +       for (i = 0; i < dmc->num_counters; i++) {
> +               dmc->counter[i] =
> +                       devfreq_event_get_edev_by_phandle(dmc->dev, i);
> +               if (IS_ERR_OR_NULL(dmc->counter[i]))
> +                       return -EPROBE_DEFER;
> +       }
> +
> +       ret = exynos5_counters_enable_edev(dmc);
> +       if (ret < 0) {
> +               dev_err(dmc->dev, "could not enable event counter\n");
> +               return ret;
> +       }
> +
> +       ret = exynos5_counters_set_event(dmc);
> +       if (ret < 0) {
> +               dev_err(dmc->dev, "counld not set event counter\n");
> +               return ret;
> +       }
> +
> +       mutex_lock(&dmc->lock);
> +       dmc->counters_enabled = true;

I do not think it is useful (counters_enabled == false cannot happen).
You call this function before registering devfreq.

> +       mutex_unlock(&dmc->lock);
> +
> +       return 0;
> +}
> +
> +static struct regmap_config exynos5_clk_regmap_cfg = {
> +       .reg_bits = 32,
> +       .val_bits = 32,
> +       .reg_stride = 4,
> +};
> +
> +static int exynos5_dmc_init_clk_regmap(struct platform_device *pdev,
> +                                      struct exynos5_dmc *dmc)
> +{
> +       struct resource *res;
> +       void __iomem *base;
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
> +       base = devm_ioremap_resource(dmc->dev, res);
> +       if (IS_ERR(base))
> +               return PTR_ERR(base);
> +
> +       exynos5_clk_regmap_cfg.max_register = resource_size(res) - 4;
> +       dmc->clk_regmap = devm_regmap_init_mmio(dmc->dev, base,
> +                                            &exynos5_clk_regmap_cfg);
> +       if (IS_ERR(dmc->clk_regmap))
> +               return PTR_ERR(dmc->clk_regmap);
> +
> +       return 0;
> +}
> +
> +#ifdef CONFIG_DEBUG_FS
> +
> +static int dmc_dbg_show_timings(struct seq_file *seq, void *na)
> +{
> +       struct exynos5_dmc *dmc = seq->private;
> +       int i, j;
> +       u32 val;
> +       struct timing_reg *reg;
> +
> +       seq_printf(seq, "timings for each frequency\n");
> +       for (j = dmc->opp_count - 1; j >= 0; j--) {
> +               seq_printf(seq, "frequency = %uMHz\n",
> +                                  dmc->opp[j].freq_hz / 1000000);
> +               seq_printf(seq, "timing_row, timing_data, timing_power\n");
> +               seq_printf(seq, "0x%08X, 0x%08X, 0x%08X\n", dmc->timing_row[j],
> +                          dmc->timing_data[j], dmc->timing_power[j]);
> +       }
> +
> +       for (j = dmc->opp_count - 1; j >= 0; j--) {
> +               seq_printf(seq, "frequency [MHz] = %u\n",
> +                                  dmc->opp[j].freq_hz / 1000000);
> +
> +               for (i = 0; i < ARRAY_SIZE(timing_row); i++) {
> +                       reg = &timing_row[i];
> +                       val = TIMING_REG2VAL(dmc->timing_row[j], reg);
> +                       seq_printf(seq, "%s = %u\n", reg->name, val);
> +               }
> +
> +               for (i = 0; i < ARRAY_SIZE(timing_data); i++) {
> +                       reg = &timing_data[i];
> +                       val = TIMING_REG2VAL(dmc->timing_data[j], reg);
> +                       seq_printf(seq, "%s = %u\n", reg->name, val);
> +               }
> +
> +               for (i = 0; i < ARRAY_SIZE(timing_power); i++) {
> +                       reg = &timing_power[i];
> +                       val = TIMING_REG2VAL(dmc->timing_power[j], reg);
> +                       seq_printf(seq, "%s = %u\n", reg->name, val);
> +               }
> +       }
> +
> +       return 0;
> +}
> +
> +static int dmc_dbg_open_timings(struct inode *inode, struct file *f)
> +{
> +       return single_open(f, dmc_dbg_show_timings, inode->i_private);
> +}
> +
> +static const char *event_get_name(const char *evt)
> +{
> +       int i;
> +
> +       for (i = 0; i < ARRAY_SIZE(event_name); i += 2) {
> +               if (!strcmp(event_name[i], evt))
> +                       return event_name[i + 1];
> +       }
> +
> +       return "Unknown";
> +}
> +
> +static int dmc_dbg_show_cnt(struct seq_file *seq, void *na)
> +{
> +       struct exynos5_dmc *dmc = seq->private;
> +       int i;
> +       struct devfreq_event_data event;
> +       struct devfreq_event_dev *edev;
> +       int ret;
> +       const char *evt_name;
> +       u64 ts_new, delta;
> +       static u64 ts;
> +
> +       seq_printf(seq, "Performance based on PMU counters\n");
> +       seq_printf(seq, "The counters could overflow every ~9.2 sec\n");
> +
> +       ts_new = ktime_get_ns();
> +       delta = ts_new - ts;
> +
> +       for (i = 0; i < dmc->num_counters; i++) {
> +               edev = dmc->counter[i];
> +               if (!edev)
> +                       continue;
> +
> +               evt_name = event_get_name(edev->desc->name);
> +
> +               ret = devfreq_event_get_event(edev, &event);
> +               if (ret < 0)
> +                       return ret;
> +
> +               seq_printf(seq, "%s = %lu / %lu\n", evt_name, event.load_count,
> +                          event.total_count);
> +       }
> +
> +       seq_printf(seq, "For last %llu ms\n",
> +                  div64_u64(delta, 1000000UL));
> +
> +       ts = ktime_get_ns();
> +       ret = exynos5_counters_set_event(dmc);
> +       if (ret < 0) {
> +               dev_err(dmc->dev, "could not set event counter\n");
> +               return ret;
> +       }
> +
> +       return 0;
> +}
> +
> +static int dmc_dbg_open_cnt(struct inode *inode, struct file *f)
> +{
> +       return single_open(f, dmc_dbg_show_cnt, inode->i_private);
> +}
> +
> +struct counter {
> +       u64 load;
> +       u64 total;
> +};
> +
> +static int dmc_dbg_show_cnt_100ms(struct seq_file *seq, void *na)
> +{
> +       struct exynos5_dmc *dmc = seq->private;
> +       int i;
> +       u64 bandwidth = 0;
> +       struct devfreq_event_data event;
> +       struct devfreq_event_dev *edev;
> +       int ret;
> +       const char *evt_name;
> +       u64 ts_new, delta;
> +       static u64 ts;
> +       struct counter *cnt;
> +       u64 total[3] = {0, 0, 0 }; /* read, write, read+write data*/
> +       const char *type[3] = {"read", "write", "read+write"};
> +       u64 bus_cyc_count = 0;
> +       int offset = 0;
> +       char *s;
> +
> +       s = kzalloc(PAGE_SIZE * sizeof(char), GFP_KERNEL);
> +       if (!s)
> +               return -ENOMEM;
> +
> +       cnt = kcalloc(dmc->num_counters, sizeof(struct counter), GFP_KERNEL);
> +       if (!cnt)
> +               return -ENOMEM;
> +
> +       ret = exynos5_counters_set_event(dmc);
> +       if (ret < 0) {
> +               dev_err(dmc->dev, "could not set event counter\n");
> +               return ret;
> +       }
> +
> +       ts = ktime_get_ns();
> +       msleep(100);
> +
> +       /* Seprate data acquisition from presentation due to some
> +          overheads. */
> +       for (i = 0; i < dmc->num_counters; i++) {
> +               edev = dmc->counter[i];
> +               if (!edev)
> +                       continue;
> +
> +               ret = devfreq_event_get_event(edev, &event);
> +               if (ret < 0)
> +                       return ret;
> +
> +               total[i % 3] += event.load_count;
> +               cnt[i].load = event.load_count;
> +               cnt[i].total = event.total_count;
> +
> +               if (bus_cyc_count < event.total_count)
> +                       bus_cyc_count = event.total_count;
> +       }
> +
> +       ts_new = ktime_get_ns();
> +       delta = ts_new - ts;
> +       if (delta == 0)
> +               delta = 1;
> +
> +       for (i = 0; i < dmc->num_counters; i++) {
> +               edev = dmc->counter[i];
> +               if (!edev)
> +                       continue;
> +
> +               evt_name = event_get_name(edev->desc->name);
> +
> +               bandwidth = (u64)cnt[i].load * AXI_BUS_WIDTH_BYTES * 1000;
> +               bandwidth = div64_u64(bandwidth, delta);
> +
> +               offset += sprintf(s + offset, "%s\t\t%llu MB/s\n",
> +                                 evt_name, bandwidth);
> +       }
> +
> +       for (i = 0; i < 3; i++) {
> +               bandwidth = (u64)total[i] * AXI_BUS_WIDTH_BYTES * 1000;
> +               bandwidth = div64_u64(bandwidth, delta);
> +
> +               offset += sprintf(s + offset, "total\t%s\t\t%llu MB/s\n",
> +                                 type[i], bandwidth);
> +       }
> +
> +       /* AXI speed is presented in MHz*/
> +       bus_cyc_count *= 1000;
> +
> +       seq_printf(seq, "Performance based on PMU counters\n");
> +       seq_printf(seq, "The counters will overflow every ~9.2 sec\n");
> +       seq_printf(seq, "%s", s);
> +       seq_printf(seq, "AXI bus frequency %llu MHz, width %u B, SDR mode\n",
> +                  div64_u64(bus_cyc_count, delta), AXI_BUS_WIDTH_BYTES);
> +       seq_printf(seq, "For last %llu ms\n",
> +                  div64_u64(delta, 1000000UL));
> +
> +       kfree(cnt);
> +       kfree(s);
> +
> +       return 0;
> +}
> +
> +static int dmc_dbg_show_cnt_100ms_raw(struct seq_file *seq, void *na)
> +{
> +       struct exynos5_dmc *dmc = seq->private;
> +       int i;
> +       struct devfreq_event_data event;
> +       struct devfreq_event_dev *edev;
> +       int ret;
> +       const char *evt_name;
> +       u64 ts_new, delta;
> +       static u64 ts;
> +       struct counter *cnt;
> +       const char *type[3] = {"read", "write", "read+write"};
> +       int offset = 0;
> +       char *s;
> +
> +       s = kzalloc(PAGE_SIZE * sizeof(char), GFP_KERNEL);
> +       if (!s)
> +               return -ENOMEM;
> +
> +       cnt = kcalloc(dmc->num_counters, sizeof(struct counter), GFP_KERNEL);
> +       if (!cnt)
> +               return -ENOMEM;
> +
> +       ret = exynos5_counters_set_event(dmc);
> +       if (ret < 0) {
> +               dev_err(dmc->dev, "could not set event counter\n");
> +               return ret;
> +       }
> +
> +       ts = ktime_get_ns();
> +       msleep(100);
> +
> +       /* Seprate data acquisition from presentation due to some
> +          overheads. */
> +       for (i = 0; i < dmc->num_counters; i++) {
> +               edev = dmc->counter[i];
> +               if (!edev)
> +                       continue;
> +
> +               ret = devfreq_event_get_event(edev, &event);
> +               if (ret < 0)
> +                       return ret;
> +
> +               cnt[i].load = event.load_count;
> +               cnt[i].total = event.total_count;
> +       }
> +
> +       ts_new = ktime_get_ns();
> +       delta = ts_new - ts;
> +       if (delta == 0)
> +               delta = 1;
> +
> +       for (i = 0; i < dmc->num_counters; i++) {
> +               edev = dmc->counter[i];
> +               if (!edev)
> +                       continue;
> +
> +               evt_name = event_get_name(edev->desc->name);
> +
> +               offset += sprintf(s + offset, "%s (%s)\t\t%llu / %llu\n",
> +                                 evt_name, type[i % 3], cnt[i].load,
> +                                 cnt[i].total);
> +       }
> +
> +       seq_printf(seq, "Performance based on PMU counters ('load'/'total')\n");
> +       seq_printf(seq, "The counters will overflow every ~9.2 sec\n");
> +       seq_printf(seq, "%s", s);
> +       seq_printf(seq, "For last %llu ms\n",
> +                  div64_u64(delta, 1000000UL));
> +
> +       kfree(cnt);
> +       kfree(s);
> +
> +       return 0;
> +}
> +
> +static int dmc_dbg_open_cnt_100ms(struct inode *inode, struct file *f)
> +{
> +       return single_open(f, dmc_dbg_show_cnt_100ms, inode->i_private);
> +}
> +
> +static int dmc_dbg_open_cnt_100ms_raw(struct inode *inode, struct file *f)
> +{
> +       return single_open(f, dmc_dbg_show_cnt_100ms_raw, inode->i_private);
> +}
> +
> +static const struct file_operations dmc_debugfs_ops_timings = {
> +       .open = dmc_dbg_open_timings,
> +       .read = seq_read,
> +       .release = single_release,
> +};
> +
> +static const struct file_operations dmc_debugfs_ops_cnt = {
> +       .open = dmc_dbg_open_cnt,
> +       .read = seq_read,
> +       .release = single_release,
> +};
> +
> +static const struct file_operations dmc_debugfs_ops_cnt_100ms = {
> +       .open = dmc_dbg_open_cnt_100ms,
> +       .read = seq_read,
> +       .release = single_release,
> +};
> +
> +static const struct file_operations dmc_debugfs_ops_cnt_100ms_raw = {
> +       .open = dmc_dbg_open_cnt_100ms_raw,
> +       .read = seq_read,
> +       .release = single_release,
> +};
> +
> +static void exynos5_dmc_debugfs_init(struct exynos5_dmc *dmc)
> +{
> +       struct dentry *dentry;
> +
> +       dmc->dbg_root = debugfs_create_dir(dev_name(dmc->dev), NULL);
> +       if (!dmc->dbg_root)
> +               return;
> +
> +       dentry = debugfs_create_file("timings", 0444, dmc->dbg_root, dmc,
> +                                    &dmc_debugfs_ops_timings);
> +       if (!dentry)
> +               goto clean_debugfs;
> +
> +       dentry = debugfs_create_file("counters", 0444, dmc->dbg_root, dmc,
> +                                    &dmc_debugfs_ops_cnt);
> +       if (!dentry)
> +               goto clean_debugfs;
> +
> +       dentry = debugfs_create_file("100ms_counters", 0444, dmc->dbg_root, dmc,
> +                                    &dmc_debugfs_ops_cnt_100ms);
> +       if (!dentry)
> +               goto clean_debugfs;
> +
> +       dentry = debugfs_create_file("100ms_raw_counters", 0444, dmc->dbg_root,
> +                                    dmc, &dmc_debugfs_ops_cnt_100ms_raw);
> +       if (!dentry)
> +               goto clean_debugfs;
> +
> +       return;
> +
> +clean_debugfs:
> +       debugfs_remove_recursive(dmc->dbg_root);
> +}
> +#else
> +static void exynos5_dmc_debugfs_init(struct exynos5_dmc *dmc)
> +{}
> +#endif
> +
> +/**
> + * exynos5_dmc_set_pause_on_switching() - Controls a pause feature in DMC
> + * @dmc:       device which is used for changing this feature
> + * @set:       a boolean state passing enable/disable request
> + *
> + * There is a need of pausing DREX DMC when divider or MUX in clock tree
> + * changes its configuration. In such situation access to the memory is blocked
> + * in DMC automatically. This feature is used when clock frequency change
> + * request appears and touches clock tree.
> + */
> +static inline int exynos5_dmc_set_pause_on_switching(struct exynos5_dmc *dmc)
> +{
> +       unsigned int val;
> +       int ret;
> +
> +       ret = regmap_read(dmc->clk_regmap, CDREX_PAUSE, &val);
> +       if (ret)
> +               return ret;
> +
> +       val |= 1UL;
> +       regmap_write(dmc->clk_regmap, CDREX_PAUSE, val);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_probe() - Probe function for the DMC driver
> + * @pdev:      platform device for which the driver is going to be initialized
> + *
> + * Initialize basic components: clocks, regulators, performance counters, etc.
> + * Read out product version and based on the information setup
> + * internal structures for the controller (frequency and voltage) and for DRAM
> + * memory parameters: timings for each operating frequency.
> + * Register new devfreq device for controlling DVFS of the DMC.
> + */
> +static int exynos5_dmc_probe(struct platform_device *pdev)
> +{
> +       int ret = 0;
> +       struct exynos5_dmc *dmc;
> +       struct device *dev = &pdev->dev;
> +       struct resource *res;
> +
> +       dmc = devm_kzalloc(dev, sizeof(*dmc), GFP_KERNEL);
> +       if (!dmc)
> +               return -ENOMEM;
> +
> +       mutex_init(&dmc->lock);
> +
> +       dmc->dev = dev;
> +       platform_set_drvdata(pdev, dmc);
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +       dmc->base_drexi0 = devm_ioremap_resource(dev, res);
> +       if (IS_ERR(dmc->base_drexi0))
> +               return PTR_ERR(dmc->base_drexi0);
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +       dmc->base_drexi1 = devm_ioremap_resource(dev, res);
> +       if (IS_ERR(dmc->base_drexi1))
> +               return PTR_ERR(dmc->base_drexi1);
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
> +       dmc->chip_id = devm_ioremap_resource(dev, res);
> +       if (IS_ERR(dmc->chip_id))
> +               return PTR_ERR(dmc->chip_id);
> +
> +       ret = exynos5_dmc_chip_revision_settings(dmc);
> +       if (ret)
> +               return ret;
> +
> +       ret = exynos5_init_freq_table(dev, dmc, &exynos5_dmc_df_profile);
> +       if (ret) {
> +               dev_warn(dev, "couldn't initialize frequency settings\n");
> +               return ret;
> +       }
> +
> +       dmc->vdd_mif = devm_regulator_get(dev, "vdd");
> +       if (IS_ERR(dmc->vdd_mif)) {
> +               ret = PTR_ERR(dmc->vdd_mif);
> +               dev_warn(dev, "couldn't get regulator\n");
> +               return ret;
> +       }
> +
> +       ret = exynos5_dmc_init_clks(dev, dmc);
> +       if (ret) {
> +               dev_warn(dev, "couldn't initialize clocks\n");
> +               return ret;
> +       }
> +
> +       ret = exynos5_dmc_init_clk_regmap(pdev, dmc);
> +       if (ret) {
> +               dev_warn(dev, "couldn't initialize clock regmap\n");
> +               return ret;
> +       }
> +
> +       ret = of_get_dram_timings(dmc);
> +       if (ret) {
> +               dev_warn(dev, "couldn't initialize timings settings\n");
> +               return ret;
> +       }
> +
> +       ret = exynos5_performance_counters_init(dmc);
> +       if (ret) {
> +               dev_warn(dev, "couldn't probe performance counters\n");
> +               goto remove_clocks;
> +       }
> +
> +       ret = exynos5_dmc_set_pause_on_switching(dmc);
> +       if (ret) {
> +               dev_warn(dev, "couldn't get access to PAUSE register\n");
> +               goto remove_clocks;
> +       }
> +
> +
> +       /*
> +        * Setup default thresholds for the devfreq governor.
> +        * The values are chosen based on experiments.
> +        */
> +       dmc->gov_data.upthreshold = 30;
> +       dmc->gov_data.downdifferential = 5;
> +
> +       dmc->df = devm_devfreq_add_device(dev, &exynos5_dmc_df_profile,
> +                                         DEVFREQ_GOV_USERSPACE,
> +                                         &dmc->gov_data);
> +
> +       if (IS_ERR(dmc->df)) {
> +               ret = PTR_ERR(dmc->df);
> +               goto err_devfreq_add;
> +       }
> +
> +       exynos5_dmc_debugfs_init(dmc);
> +
> +       dev_info(&pdev->dev, "DMC init for prod_id=0x%08x pkg_id=0x%08x\n",
> +                dmc->prod_rev, dmc->pkg_rev);
> +
> +       return 0;
> +
> +err_devfreq_add:
> +       exynos5_counters_disable_edev(dmc);
> +remove_clocks:
> +       clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
> +       clk_disable_unprepare(dmc->mout_spll);
> +
> +       return ret;
> +}
> +
> +/**
> + * exynos5_dmc_remove() - Remove function for the platform device
> + * @pdev:      platform device which is going to be removed
> + *
> + * The function relies on 'devm' framework function which automatically
> + * clean the device's resources. It just calls explicitly disable function for
> + * the performance counters.
> + */
> +static int exynos5_dmc_remove(struct platform_device *pdev)
> +{
> +       struct exynos5_dmc *dmc = dev_get_drvdata(&pdev->dev);
> +
> +       exynos5_counters_disable_edev(dmc);
> +
> +       clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
> +       clk_disable_unprepare(dmc->mout_spll);
> +
> +       dev_pm_opp_remove_table(&pdev->dev);
> +
> +       dev_info(&pdev->dev, "DMC removed\n");
> +
> +       return 0;
> +}
> +
> +static const struct of_device_id exynos5_dmc_of_match[] = {
> +       { .compatible = "samsung,exynos5422-dmc", },
> +       { },
> +};
> +MODULE_DEVICE_TABLE(of, exynos5_dmc_of_match);
> +
> +static struct platform_driver exynos5_dmc_platdrv = {
> +       .probe  = exynos5_dmc_probe,
> +       .remove = exynos5_dmc_remove,
> +       .driver = {
> +               .name   = "exynos5-dmc",
> +               .of_match_table = exynos5_dmc_of_match,
> +       },
> +};
> +module_platform_driver(exynos5_dmc_platdrv);
> +MODULE_DESCRIPTION("Driver for Exynos5422 Dynamic Memory Controller dynamic frequency and voltage change"

Unneeded empty line.

Best regards,
Krzysztof

Re: [PATCH v6 07/10] drivers: memory: add DMC driver for Exynos5422

[Lukasz Luba]

Hi Krzysztof,

On 4/23/19 1:27 PM, Krzysztof Kozlowski wrote:
> On Fri, 19 Apr 2019 at 16:19, Lukasz Luba <l.luba@partner.samsung.com> wrote:
>>
>> This patch adds driver for Exynos5422 Dynamic Memory Controller.
>> The driver provides support for dynamic frequency and voltage scaling for
>> DMC and DRAM. It supports changing timings of DRAM running with different
>> frequency. There is also an algorithm to calculate timigns based on
>> memory description provided in DT.
>> The patch also contains needed MAINTAINERS file update.
>>
>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>> ---
>>   MAINTAINERS                             |    8 +
>>   drivers/memory/samsung/Kconfig          |   17 +
>>   drivers/memory/samsung/Makefile         |    1 +
>>   drivers/memory/samsung/exynos5422-dmc.c | 1793 +++++++++++++++++++++++++++++++
>>   4 files changed, 1819 insertions(+)
>>   create mode 100644 drivers/memory/samsung/exynos5422-dmc.c
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index 1ba4b9b..07e257d 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -3395,6 +3395,14 @@ S:       Maintained
>>   F:     drivers/devfreq/exynos-bus.c
>>   F:     Documentation/devicetree/bindings/devfreq/exynos-bus.txt
>>
>> +DMC FREQUENCY DRIVER FOR SAMSUNG EXYNOS5422
>> +M:     Lukasz Luba <l.luba@partner.samsung.com>
>> +L:     linux-pm@vger.kernel.org
>> +L:     linux-samsung-soc@vger.kernel.org
>> +S:     Maintained
>> +F:     drivers/memory/samsung/exynos5422-dmc.c
>> +F:     Documentation/devicetree/bindings/memory-controllers/exynos5422-dmc.txt
>> +
>>   BUSLOGIC SCSI DRIVER
>>   M:     Khalid Aziz <khalid@gonehiking.org>
>>   L:     linux-scsi@vger.kernel.org
>> diff --git a/drivers/memory/samsung/Kconfig b/drivers/memory/samsung/Kconfig
>> index 79ce7ea..202972b 100644
>> --- a/drivers/memory/samsung/Kconfig
>> +++ b/drivers/memory/samsung/Kconfig
>> @@ -5,6 +5,23 @@ config SAMSUNG_MC
>>            Support for the Memory Controller (MC) devices found on
>>            Samsung Exynos SoCs.
>>
>> +config ARM_EXYNOS5422_DMC
>> +       tristate "ARM EXYNOS5422 Dynamic Memory Controller driver"
>> +       depends on ARCH_EXYNOS || COMPILE_TEST
>> +       select DDR
>> +       select PM_DEVFREQ
>> +       select DEVFREQ_GOV_SIMPLE_ONDEMAND
>> +       select DEVFREQ_GOV_USERSPACE
>> +       select PM_DEVFREQ_EVENT
>> +       select PM_OPP
>> +       help
>> +         This adds driver for Exynos5422 DMC (Dynamic Memory Controller).
>> +         The driver provides support for Dynamic Voltage and Frequency Scaling in
>> +         DMC and DRAM. It also supports changing timings of DRAM running with
>> +         different frequency. The timings are calculated based on DT memory
>> +         information.
>> +
>> +
>>   if SAMSUNG_MC
>>
>>   config EXYNOS_SROM
>> diff --git a/drivers/memory/samsung/Makefile b/drivers/memory/samsung/Makefile
>> index 00587be..4f6e438 100644
>> --- a/drivers/memory/samsung/Makefile
>> +++ b/drivers/memory/samsung/Makefile
>> @@ -1,2 +1,3 @@
>>   # SPDX-License-Identifier: GPL-2.0
>> +obj-$(CONFIG_ARM_EXYNOS5422_DMC)       += exynos5422-dmc.o
>>   obj-$(CONFIG_EXYNOS_SROM)      += exynos-srom.o
>> diff --git a/drivers/memory/samsung/exynos5422-dmc.c b/drivers/memory/samsung/exynos5422-dmc.c
>> new file mode 100644
>> index 0000000..fa4cd4c
>> --- /dev/null
>> +++ b/drivers/memory/samsung/exynos5422-dmc.c
>> @@ -0,0 +1,1793 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (c) 2019 Samsung Electronics Co., Ltd.
>> + */
>> +
>> +#include <linux/clk.h>
>> +#include <linux/debugfs.h>
>> +#include <linux/delay.h>
>> +#include <linux/devfreq.h>
>> +#include <linux/devfreq-event.h>
>> +#include <linux/device.h>
>> +#include <linux/export.h>
> 
> Do you use it?
Good point, I have deleted some code but forgot to check includes.
> 
>> +#include <linux/io.h>
>> +#include <linux/module.h>
>> +#include <linux/of_device.h>
>> +#include <linux/pm_opp.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/regmap.h>
>> +#include <linux/regulator/consumer.h>
>> +#include <linux/seq_file.h>
>> +#include <linux/slab.h>
>> +#include <memory/jedec_ddr.h>
>> +#include "../of_memory.h"
>> +
>> +#define EXYNOS5_DREXI_TIMINGAREF               (0x0030)
>> +#define EXYNOS5_DREXI_TIMINGROW0               (0x0034)
>> +#define EXYNOS5_DREXI_TIMINGDATA0              (0x0038)
>> +#define EXYNOS5_DREXI_TIMINGPOWER0             (0x003C)
>> +#define EXYNOS5_DREXI_TIMINGROW1               (0x00E4)
>> +#define EXYNOS5_DREXI_TIMINGDATA1              (0x00E8)
>> +#define EXYNOS5_DREXI_TIMINGPOWER1             (0x00EC)
>> +#define CDREX_PAUSE                            (0x91c)
>> +#define CDREX_LPDDR3PHY_CON3                   (0xa20)
>> +#define EXYNOS5_TIMING_SET_SWI                  (1UL << 28)
>> +#define USE_MX_MSPLL_TIMINGS                   (1)
>> +#define USE_BPLL_TIMINGS                       (0)
>> +
>> +#define EXYNOS5_AREF_NORMAL                    (0x2e)
>> +
>> +#define IS_MEM_2GB(val) \
>> +       (                                               \
>> +        (((val) & 0xf0) & 0x20) ? 1 :                  \
>> +               (((val) & 0xf0) & 0x30) ? 1 : 0         \
>> +       )
>> +
>> +#define EXYNOS5_POP_OPTIONS(val)       (((val >> 4) & 0x3UL) << 4)
>> +#define EXYNOS5_DDR_TYPE(val)          (((val >> 14) & 0x1UL))
> 
> I would prefer to split out this and code related to chipid to chipid
> driver. Sylwester was adding similar parts for ASV so please unify it
> consistently. IOW, if you need data from chipid I would prefer to get
> it from chipid driver. This way we keep given feature only in one
> driver - less code duplication, less logic spread all over, no need to
> map the same region in multiple drivers.
Right, I have talked with Sylwester and I will align to the common code.
It will use regmap to access the register. In DT there will be phandle
to the 'chipid' node in memory-controller.
> 
>> +
>> +#define EXYNOS5_CHIP_PROD_ID           (0)
>> +#define EXYNOS5_CHIP_PKG_ID            (4)
>> +
>> +#define PPMU_PMCNT_CONST_RATIO_MUL     15
>> +#define PPMU_PMCNT_CONST_RATIO_DIV     10
>> +
>> +#define AXI_BUS_WIDTH_BYTES (128 >> 3)
>> +
>> +/**
>> + * enum dmc_slot_id - An enum with slots in DMC
> 
> The comment copies the name so please remove it. Comment should bring
> new information, not copy the source code.
Comment will be removed.
> 
>> + */
>> +enum dmc_slot_id {
>> +       DMC0_0,
>> +       DMC0_1,
>> +       DMC1_0,
>> +       DMC1_1,
>> +       DMC_SLOTS_END
>> +};
>> +
>> +/**
>> + * struct dmc_slot_info - Describes DMC's slot
>> + *
>> + * The structure holds DMC's slot name which is part of the device name
>> + * provided in DT. Each slot has particular share of the DMC bandwidth.
>> + * To abstract the model performance and values in performance counters,
>> + * fields 'ratio_mul' and 'ratio_div' are used in calculation algorithm
>> + * for each slot. Please check the corresponding function with the algorithm,
>> + * to see how these variables are used.
>> + */
>> +struct dmc_slot_info {
>> +       char *name;
>> +       int id;
>> +       int ratio_mul;
>> +       int ratio_div;
>> +};
>> +
>> +/**
>> + * struct dmc_opp_table - Operating level desciption
>> + *
>> + * Covers frequency and voltage settings of the DMC operating mode.
>> + */
>> +struct dmc_opp_table {
>> +       u32 freq_hz;
>> +       u32 volt_uv;
>> +};
>> +
>> +/**
>> + * struct exynos5_dmc - main structure describing DMC device
>> + *
>> + * The main structure for the Dynamic Memory Controller which covers clocks,
>> + * memory regions, HW information, parameters and current operating mode.
>> + */
>> +struct exynos5_dmc {
>> +       struct device *dev;
>> +       struct devfreq *df;
>> +       struct devfreq_simple_ondemand_data gov_data;
>> +       void __iomem *base_drexi0;
>> +       void __iomem *base_drexi1;
>> +       void __iomem *chip_id;
>> +       struct regmap *clk_regmap;
>> +       struct mutex lock;
>> +       unsigned long curr_rate;
>> +       unsigned long curr_volt;
>> +       unsigned long bypass_rate;
>> +       struct dmc_opp_table *opp;
>> +       struct dmc_opp_table opp_bypass;
>> +       int opp_count;
>> +       u32 timings_arr_size;
>> +       u32 *timing_row;
>> +       u32 *timing_data;
>> +       u32 *timing_power;
>> +       const struct lpddr3_timings *timings;
>> +       const struct lpddr3_min_tck *min_tck;
>> +       u32 bypass_timing_row;
>> +       u32 bypass_timing_data;
>> +       u32 bypass_timing_power;
>> +       unsigned int prod_rev;
>> +       unsigned int pkg_rev;
>> +       unsigned int mem_info;
>> +       struct regulator *vdd_mif;
>> +       struct clk *fout_spll;
>> +       struct clk *fout_bpll;
>> +       struct clk *mout_spll;
>> +       struct clk *mout_bpll;
>> +       struct clk *mout_mclk_cdrex;
>> +       struct clk *dout_clk2x_phy0;
>> +       struct clk *mout_mx_mspll_ccore;
>> +       struct clk *mx_mspll_ccore_phy;
>> +       struct clk *mout_mx_mspll_ccore_phy;
>> +       struct devfreq_event_dev **counter;
>> +       int num_counters;
>> +       bool counters_enabled;
>> +#ifdef CONFIG_DEBUG_FS
>> +       struct dentry *dbg_root;
>> +#endif
>> +};
>> +
>> +#define TIMING_FIELD(t_name, t_bit_beg, t_bit_end) \
>> +       { .name = t_name, .bit_beg = t_bit_beg, .bit_end = t_bit_end }
>> +
>> +#define TIMING_VAL(timing_array, id, t_val)                    \
>> +({                                                             \
>> +               u32 __val;                              \
>> +               __val = t_val << timing_array[id].bit_beg;      \
>> +               __val;                                          \
>> +})
>> +
>> +#define TIMING_VAL2REG(timing, t_val)                  \
>> +({                                                             \
>> +               u32 __val;                              \
>> +               __val = t_val << timing->bit_beg;       \
>> +               __val;                                          \
>> +})
>> +
>> +#define TIMING_REG2VAL(reg, timing)                    \
>> +({                                                             \
>> +               u32 __val;                              \
>> +               reg <<= (31 - timing->bit_end);         \
>> +               reg >>= (31 - timing->bit_end);         \
>> +               __val = reg >> timing->bit_beg; \
>> +               __val;                                          \
>> +})
>> +
>> +struct timing_reg {
>> +       char *name;
>> +       int bit_beg;
>> +       int bit_end;
>> +       unsigned int val;
>> +};
>> +
>> +static struct timing_reg timing_row[] = {
>> +       TIMING_FIELD("tRFC", 24, 31),
>> +       TIMING_FIELD("tRRD", 20, 23),
>> +       TIMING_FIELD("tRP", 16, 19),
>> +       TIMING_FIELD("tRCD", 12, 15),
>> +       TIMING_FIELD("tRC", 6, 11),
>> +       TIMING_FIELD("tRAS", 0, 5),
>> +};
>> +
>> +static struct timing_reg timing_data[] = {
>> +       TIMING_FIELD("tWTR", 28, 31),
>> +       TIMING_FIELD("tWR", 24, 27),
>> +       TIMING_FIELD("tRTP", 20, 23),
>> +       TIMING_FIELD("tW2W-C2C", 14, 14),
>> +       TIMING_FIELD("tR2R-C2C", 12, 12),
>> +       TIMING_FIELD("WL", 8, 11),
>> +       TIMING_FIELD("tDQSCK", 4, 7),
>> +       TIMING_FIELD("RL", 0, 3),
>> +};
>> +
>> +static struct timing_reg timing_power[] = {
> 
> All these looks like const. At least I could not see any writes to them.
They will be changed to const.
> 
>> +       TIMING_FIELD("tFAW", 26, 31),
>> +       TIMING_FIELD("tXSR", 16, 25),
>> +       TIMING_FIELD("tXP", 8, 15),
>> +       TIMING_FIELD("tCKE", 4, 7),
>> +       TIMING_FIELD("tMRD", 0, 3),
>> +};
>> +
>> +#define TIMING_COUNT (ARRAY_SIZE(timing_row) + ARRAY_SIZE(timing_data) + \
>> +                     ARRAY_SIZE(timing_power))
>> +
>> +/**
>> + * exynos5_counters_fname() - Macro generating function for event devices
>> + * @f:         function name suffix
>> + *
>> + * Macro which generates needed function for manipulation of event devices.
>> + * It aims to avoid code duplication relaying on similar prefix and function
>> + * parameters in the devfreq event device framework functions.
>> + */
>> +#define exynos5_counters_fname(f)                              \
>> +static int exynos5_counters_##f(struct exynos5_dmc *dmc)       \
>> +{                                                              \
>> +       int i, ret;                                             \
>> +                                                               \
>> +       for (i = 0; i < dmc->num_counters; i++) {               \
>> +               if (!dmc->counter[i])                           \
>> +                       continue;                               \
>> +               ret = devfreq_event_##f(dmc->counter[i]);       \
>> +               if (ret < 0)                                    \
>> +                       return ret;                             \
>> +       }                                                       \
>> +       return 0;                                               \
>> +}
>> +
>> +/* Declarations for the function generated by the macro above. */
>> +static int exynos5_counters_set_event(struct exynos5_dmc *dmc);
>> +static int exynos5_counters_enable_edev(struct exynos5_dmc *dmc);
>> +static int exynos5_counters_disable_edev(struct exynos5_dmc *dmc);
> 
> You save some lines of code but make it more difficult to follow and
> understand. I do not think it is worth the effort especially that
> duplicated code is not difficult... so I prefer duplication than
> obfuscation in such case. Define regular functions.
I agree, these functions will be written in normal way.
> 
>> +
>> +/* Generate needed functions for managing event device. */
>> +exynos5_counters_fname(set_event);
>> +exynos5_counters_fname(enable_edev);
>> +exynos5_counters_fname(disable_edev);
>> +
>> +/* Event names to DMC channel and slot with proper data count type */
>> +static const char *event_name[] = {
>> +       /* Counters for DMC0 slot 0 */
>> +       "ppmu-event0-dmc0_0",
>> +       "DMC0_0-Read",
>> +       "ppmu-event1-dmc0_0",
>> +       "DMC0_0-Write",
>> +       "ppmu-event3-dmc0_0",
>> +       "DMC0_0-Read+Write",
>> +       /* Counters for DMC0 slot 1 */
>> +       "ppmu-event0-dmc0_1",
>> +       "DMC0_1-Read",
>> +       "ppmu-event1-dmc0_1",
>> +       "DMC0_1-Write",
>> +       "ppmu-event3-dmc0_1",
>> +       "DMC0_1-Read+Write",
>> +       /* Counters for DMC1 slot 0 */
>> +       "ppmu-event0-dmc1_0",
>> +       "DMC1_0-Read",
>> +       "ppmu-event1-dmc1_0",
>> +       "DMC1_0-Write",
>> +       "ppmu-event3-dmc1_0",
>> +       "DMC1_0-Read+Write",
>> +       /* Counters for DMC1 slot 0 */
>> +       "ppmu-event0-dmc1_1",
>> +       "DMC1_1-Read",
>> +       "ppmu-event1-dmc1_1",
>> +       "DMC1_1-Write",
>> +       "ppmu-event3-dmc1_1",
>> +       "DMC1_1-Read+Write",
>> +};
>> +
>> +/**
>> + * find_target_freq_id() - Finds requested frequency in local DMC configuration
>> + * @dmc:       device for which the information is checked
>> + * @target_rate:       requested frequency in KHz
>> + *
>> + * Seeks in the local DMC driver structure for the requested frequency value
>> + * and returns index or error value.
>> + */
>> +static int find_target_freq_idx(struct exynos5_dmc *dmc,
>> +                               unsigned long target_rate)
>> +{
>> +       int i;
>> +
>> +       for (i = dmc->opp_count - 1; i >= 0; i--)
>> +               if (dmc->opp[i].freq_hz <= target_rate)
>> +                       return i;
>> +
>> +       return -EINVAL;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_chip_revision_settings() - Chooses proper DMC's configuration
>> + * @dmc:       device for which is going to be checked and configured
>> + *
>> + * Function checks the HW product information in order to choose proper
>> + * configuration for DMC frequency, voltage and DRAM timings.
>> + */
>> +static int exynos5_dmc_chip_revision_settings(struct exynos5_dmc *dmc)
>> +{
>> +       unsigned int val;
>> +
>> +       val = readl(dmc->chip_id + EXYNOS5_CHIP_PROD_ID);
>> +       dmc->prod_rev = val;
>> +
>> +       val = readl(dmc->chip_id + EXYNOS5_CHIP_PKG_ID);
>> +       dmc->pkg_rev = val;
>> +
>> +       dmc->mem_info = EXYNOS5_POP_OPTIONS(val);
>> +       dmc->mem_info |= EXYNOS5_DDR_TYPE(val);
>> +
>> +       if (!IS_MEM_2GB(dmc->mem_info)) {
>> +               dev_warn(dmc->dev, "DRAM memory type not supported\n");
>> +               return -EINVAL;
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * exynos5_switch_timing_regs() - Changes bank register set for DRAM timings
>> + * @dmc:       device for which the new settings is going to be applied
>> + * @set:       boolean variable passing set value
>> + *
>> + * Changes the register set, which holds timing parameters.
>> + * There is two register sets: 0 and 1. The register set 0
>> + * is used in normal operation when the clock is provided from main PLL.
>> + * The bank register set 1 is used when the main PLL frequency is going to be
>> + * changed and the clock is taken from alternative, stable source.
>> + * This function switches between these banks according to the
>> + * currently used clock source.
>> + */
>> +static void exynos5_switch_timing_regs(struct exynos5_dmc *dmc, bool set)
>> +{
>> +       unsigned int reg;
>> +       int ret;
>> +
>> +       ret = regmap_read(dmc->clk_regmap, CDREX_LPDDR3PHY_CON3, &reg);
>> +
>> +       if (set)
>> +               reg |= EXYNOS5_TIMING_SET_SWI;
>> +       else
>> +               reg &= ~EXYNOS5_TIMING_SET_SWI;
>> +
>> +       regmap_write(dmc->clk_regmap, CDREX_LPDDR3PHY_CON3, reg);
>> +}
>> +
>> +/**
>> + * exynos5_init_freq_table() - Initialized PM OPP framework
>> + * @dev:       devfreq device for which the OPP table is going to be
>> + *             initialized
>> + * @dmc:       DMC device for which the frequencies are used for OPP init
>> + * @profile:   devfreq device's profile
>> + *
>> + * Populate the devfreq device's OPP table based on current frequency, voltage.
>> + */
>> +static int exynos5_init_freq_table(struct device *dev, struct exynos5_dmc *dmc,
>> +                                  struct devfreq_dev_profile *profile)
>> +{
>> +       int i, ret;
>> +       int idx;
>> +       unsigned long freq;
>> +
>> +       ret = dev_pm_opp_of_add_table(dev);
>> +       if (ret < 0) {
>> +               dev_err(dev, "Failed to get OPP table\n");
>> +               return ret;
>> +       }
>> +
>> +       dmc->opp_count = dev_pm_opp_get_opp_count(dev);
>> +
>> +       dmc->opp = devm_kmalloc_array(dmc->dev, dmc->opp_count,
>> +                                     sizeof(struct dmc_opp_table), GFP_KERNEL);
>> +       if (!dmc->opp)
>> +               goto err_opp;
>> +
>> +       idx = dmc->opp_count - 1;
>> +       for (i = 0, freq = ULONG_MAX; i < dmc->opp_count; i++, freq--) {
>> +               struct dev_pm_opp *opp;
>> +
>> +               opp = dev_pm_opp_find_freq_floor(dev, &freq);
>> +               if (IS_ERR(opp))
>> +                       goto err_free_tables;
>> +
>> +               dmc->opp[idx - i].freq_hz = freq;
>> +               dmc->opp[idx - i].volt_uv = dev_pm_opp_get_voltage(opp);
>> +
>> +               dev_pm_opp_put(opp);
>> +       }
>> +
>> +       return 0;
>> +
>> +err_free_tables:
>> +       kfree(dmc->opp);
>> +err_opp:
>> +       dev_pm_opp_of_remove_table(dev);
>> +
>> +       return -EINVAL;
>> +}
>> +
>> +/**
>> + * exynos5_set_bypass_dram_timings() - Low-level changes of the DRAM timings
>> + * @dmc:       device for which the new settings is going to be applied
>> + * @param:     DRAM parameters which passes timing data
>> + *
>> + * Low-level function for changing timings for DRAM memory clocking from
>> + * 'bypass' clock source (fixed frequency @400MHz).
>> + * It uses timing bank registers set 1.
>> + */
>> +static void exynos5_set_bypass_dram_timings(struct exynos5_dmc *dmc)
>> +{
>> +       writel(EXYNOS5_AREF_NORMAL,
>> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
>> +
>> +       writel(dmc->bypass_timing_row,
>> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW1);
>> +       writel(dmc->bypass_timing_row,
>> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW1);
>> +       writel(dmc->bypass_timing_data,
>> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA1);
>> +       writel(dmc->bypass_timing_data,
>> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA1);
>> +       writel(dmc->bypass_timing_power,
>> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER1);
>> +       writel(dmc->bypass_timing_power,
>> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER1);
>> +}
>> +
>> +/**
>> + * exynos5_dram_change_timings() - Low-level changes of the DRAM final timings
>> + * @dmc:       device for which the new settings is going to be applied
>> + * @target_rate:       target frequency of the DMC
>> + *
>> + * Low-level function for changing timings for DRAM memory operating from main
>> + * clock source (BPLL), which can have different frequencies. Thus, each
>> + * frequency must have corresponding timings register values in order to keep
>> + * the needed delays.
>> + * It uses timing bank registers set 0.
>> + */
>> +static int exynos5_dram_change_timings(struct exynos5_dmc *dmc,
>> +                                      unsigned long target_rate)
>> +{
>> +       int idx;
>> +
>> +       for (idx = dmc->opp_count - 1; idx >= 0; idx--)
>> +               if (dmc->opp[idx].freq_hz <= target_rate)
>> +                       break;
>> +
>> +       if (idx < 0)
>> +               return -EINVAL;
>> +
>> +       writel(EXYNOS5_AREF_NORMAL,
>> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
>> +
>> +       writel(dmc->timing_row[idx],
>> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW0);
>> +       writel(dmc->timing_row[idx],
>> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW0);
>> +       writel(dmc->timing_data[idx],
>> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA0);
>> +       writel(dmc->timing_data[idx],
>> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA0);
>> +       writel(dmc->timing_power[idx],
>> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER0);
>> +       writel(dmc->timing_power[idx],
>> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER0);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_align_target_voltage() - Sets the final voltage for the DMC
>> + * @dmc:       device for which it is going to be set
>> + * @target_volt:       new voltage which is chosen to be final
>> + *
>> + * Function tries to align voltage to the safe level for 'normal' mode.
>> + * It checks the need of higher voltage and changes the value. The target
>> + * voltage might be lower that currently set and still the system will be
>> + * stable.
>> + */
>> +static int exynos5_dmc_align_target_voltage(struct exynos5_dmc *dmc,
>> +                                           unsigned long target_volt)
>> +{
>> +       int ret = 0;
>> +
>> +       if (dmc->curr_volt > target_volt) {
>> +               ret = regulator_set_voltage(dmc->vdd_mif, target_volt,
>> +                                           target_volt);
>> +               if (!ret)
>> +                       dmc->curr_volt = target_volt;
>> +       }
>> +
>> +       return ret;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_align_bypass_voltage() - Sets the voltage for the DMC
>> + * @dmc:       device for which it is going to be set
>> + * @target_volt:       new voltage which is chosen to be final
>> + *
>> + * Function tries to align voltage to the safe level for the 'bypass' mode.
>> + * It checks the need of higher voltage and changes the value.
>> + * The target voltage must not be less than currently needed, because
>> + * for current frequency the device might become unstable.
>> + */
>> +static int exynos5_dmc_align_bypass_voltage(struct exynos5_dmc *dmc,
>> +                                           unsigned long target_volt)
>> +{
>> +       int ret = 0;
>> +       unsigned long bypass_volt = dmc->opp_bypass.volt_uv;
>> +
>> +       target_volt = max(bypass_volt, target_volt);
>> +
>> +       if (dmc->curr_volt >= target_volt)
>> +               return 0;
>> +
>> +       ret = regulator_set_voltage(dmc->vdd_mif, target_volt,
>> +                                   target_volt);
>> +       if (!ret)
>> +               dmc->curr_volt = target_volt;
>> +
>> +       return ret;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_align_bypass_dram_timings() - Chooses and sets DRAM timings
>> + * @dmc:       device for which it is going to be set
>> + * @target_rate:       new frequency which is chosen to be final
>> + *
>> + * Function changes the DRAM timings for the temporary 'bypass' mode.
>> + */
>> +static int exynos5_dmc_align_bypass_dram_timings(struct exynos5_dmc *dmc,
>> +                                                unsigned long target_rate)
>> +{
>> +       int idx = find_target_freq_idx(dmc, target_rate);
>> +
>> +       if (idx < 0)
>> +               return -EINVAL;
>> +
>> +       exynos5_set_bypass_dram_timings(dmc);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_switch_to_bypass_configuration() - Switching to temporary clock
>> + * @dmc:       DMC device for which the switching is going to happen
>> + * @target_rate:       new frequency which is going to be set as a final
>> + * @target_volt:       new voltage which is going to be set as a final
>> + *
>> + * Function configures DMC and clocks for operating in temporary 'bypass' mode.
>> + * This mode is used only temporary but if required, changes voltage and timings
>> + * for DRAM chips. It switches the main clock to stable clock source for the
>> + * period of the main PLL reconfiguration.
>> + */
>> +static int exynos5_dmc_switch_to_bypass_configuration(struct exynos5_dmc *dmc,
>> +                                  unsigned long target_rate,
>> +                                  unsigned long target_volt)
>> +{
>> +       int ret;
>> +
>> +       /*
>> +        * Having higher voltage for a particular frequency does not harm
>> +        * the chip. Use it for the temporary frequency change when one
>> +        * voltage manipulation might be avoided.
>> +        */
>> +       ret = exynos5_dmc_align_bypass_voltage(dmc, target_volt);
>> +       if (ret)
>> +               return ret;
>> +
>> +       /*
>> +        * Longer delays for DRAM does not cause crash, the opposite does.
>> +        */
>> +       ret = exynos5_dmc_align_bypass_dram_timings(dmc, target_rate);
>> +       if (ret)
>> +               return ret;
>> +
>> +       /*
>> +        * Delays are long enough, so use them for the new coming clock.
>> +        */
>> +       exynos5_switch_timing_regs(dmc, USE_MX_MSPLL_TIMINGS);
>> +
>> +       /*
>> +        * Voltage is set at least to a level needed for this frequency,
>> +        * so switching clock source is safe now.
>> +        */
>> +       clk_prepare_enable(dmc->fout_spll);
>> +       clk_prepare_enable(dmc->mout_spll);
>> +       clk_prepare_enable(dmc->mout_mx_mspll_ccore);
> 
> Move the clock handling to the same function when you disable them. It
> makes it easy to review whether you have unbalanced enable/disable.
OK, I will move it below this function call.
> 
>> +
>> +       ret = clk_set_parent(dmc->mout_mclk_cdrex, dmc->mout_mx_mspll_ccore);
>> +
>> +       return ret;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_change_freq_and_volt() - Changes voltage and frequency of the DMC
>> + * using safe procedure
>> + * @dmc:       device for which the frequency is going to be changed
>> + * @target_rate:       requested new frequency
>> + * @target_volt:       requested voltage which corresponds to the new frequency
>> + *
>> + * The DMC frequency change procedure requires a few steps.
>> + * The main requirement is to change the clock source in the clk mux
>> + * for the time of main clock PLL locking. The assumption is that the
>> + * alternative clock source set as parent is stable.
>> + * The second parent's clock frequency is fixed to 400MHz, it is named 'bypass'
>> + * clock. This requires alignment in DRAM timing parameters for the new
>> + * T-period. There is two bank sets for keeping DRAM
>> + * timings: set 0 and set 1. The set 0 is used when main clock source is
>> + * chosen. The 2nd set of regs is used for 'bypass' clock. Switching between
>> + * the two bank sets is part of the process.
>> + * The voltage must also be aligned to the minimum required level. There is
>> + * this intermediate step with switching to 'bypass' parent clock source.
>> + * if the old voltage is lower, it requires an increase of the voltage level.
>> + * The complexity of the voltage manipulation is hidden in low level function.
>> + * In this function there is last alignment of the voltage level at the end.
>> + */
>> +static int
>> +exynos5_dmc_change_freq_and_volt(struct exynos5_dmc *dmc,
>> +                                unsigned long target_rate,
>> +                                unsigned long target_volt)
>> +{
>> +       int ret;
>> +
>> +       ret = exynos5_dmc_switch_to_bypass_configuration(dmc, target_rate,
>> +                                                        target_volt);
>> +       if (ret)
>> +               return ret;
>> +
>> +       /* We are safe to increase the timings for current bypass frequency.
> 
> Start with /* alone.
OK
> 
>> +        * Thanks to this the settings we be ready for the upcoming clock source
>> +        * change.
>> +        */
>> +       exynos5_dram_change_timings(dmc, target_rate);
>> +
>> +       clk_set_rate(dmc->fout_bpll, target_rate);
>> +
>> +       exynos5_switch_timing_regs(dmc, USE_BPLL_TIMINGS);
>> +
>> +       ret = clk_set_parent(dmc->mout_mclk_cdrex, dmc->mout_bpll);
>> +       if (ret)
>> +               return ret;
>> +
>> +       clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
>> +       clk_disable_unprepare(dmc->mout_spll);
>> +       clk_disable_unprepare(dmc->fout_spll);
>> +       /* Make sure if the voltage is not from 'bypass' settings and align to
>> +        * the right level for power efficiency.
>> +        */
>> +       ret = exynos5_dmc_align_target_voltage(dmc, target_volt);
>> +
>> +       return ret;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_get_volt_freq() - Gets the frequency and voltage from the OPP
>> + * table.
>> + * @dev:       device for which the frequency is going to be changed
>> + * @freq:       requested frequency in KHz
>> + * @target_rate:       returned frequency which is the same or lower than
>> + *                     requested
>> + * @target_volt:       returned voltage which corresponds to the returned
>> + *                     frequency
>> + *
>> + * Function gets requested frequency and checks OPP framework for needed
>> + * frequency and voltage. It populates the values 'target_rate' and
>> + * 'target_volt' or returns error value when OPP framework fails.
>> + */
>> +static int exynos5_dmc_get_volt_freq(struct device *dev, unsigned long *freq,
>> +                                    unsigned long *target_rate,
>> +                                    unsigned long *target_volt, u32 flags)
>> +{
>> +       struct dev_pm_opp *opp;
>> +
>> +       opp = devfreq_recommended_opp(dev, freq, flags);
>> +       if (IS_ERR(opp))
>> +               return PTR_ERR(opp);
>> +
>> +       *target_rate = dev_pm_opp_get_freq(opp);
>> +       *target_volt = dev_pm_opp_get_voltage(opp);
>> +       dev_pm_opp_put(opp);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_target() - Function responsible for changing frequency of DMC
>> + * @dev:       device for which the frequency is going to be changed
>> + * @freq:      requested frequency in KHz
>> + * @flags:     flags provided for this frequency change request
>> + *
>> + * An entry function provided to the devfreq framework which provides frequency
>> + * change of the DMC. The function gets the possible rate from OPP table based
>> + * on requested frequency. It calls the next function responsible for the
>> + * frequency and voltage change. In case of failure, does not set 'curr_rate'
>> + * and returns error value to the framework.
>> + */
>> +static int exynos5_dmc_target(struct device *dev, unsigned long *freq,
>> +                             u32 flags)
>> +{
>> +       struct exynos5_dmc *dmc = dev_get_drvdata(dev);
>> +       unsigned long target_rate = 0;
>> +       unsigned long target_volt = 0;
>> +       int ret;
>> +
>> +       ret = exynos5_dmc_get_volt_freq(dev, freq, &target_rate, &target_volt,
>> +                                       flags);
>> +
>> +       if (ret)
>> +               return ret;
>> +
>> +       if (target_rate == dmc->curr_rate)
>> +               return 0;
>> +
>> +       mutex_lock(&dmc->lock);
>> +
>> +       ret = exynos5_dmc_change_freq_and_volt(dmc, target_rate, target_volt);
>> +
>> +       if (ret) {
>> +               mutex_unlock(&dmc->lock);
>> +               return ret;
>> +       }
>> +
>> +       dmc->curr_rate = target_rate;
>> +
>> +       mutex_unlock(&dmc->lock);
>> +       return 0;
>> +}
>> +
>> +/**
>> + * exynos5_counters_get() - Gets the performance counters values.
>> + * @dmc:       device for which the counters are going to be checked
>> + * @load_count:        variable which is populated with counter value
>> + * @total_count:       variable which is used as 'wall clock' reference
>> + *
>> + * Function which provides performance counters values. It sums up counters for
>> + * two DMC channels. The 'total_count' is used as a reference and max value.
>> + * The ratio 'load_count/total_count' shows the busy percentage [0%, 100%].
>> + */
>> +static int exynos5_counters_get(struct exynos5_dmc *dmc,
>> +                               unsigned long *load_count,
>> +                               unsigned long *total_count)
>> +{
>> +       unsigned long total = 0;
>> +       struct devfreq_event_data event;
>> +       int ret, i;
>> +
>> +       *load_count = 0;
>> +
>> +       /* Take into account only read+write counters, but stop all */
>> +       for (i = 0; i < dmc->num_counters; i++) {
>> +               if (!dmc->counter[i])
>> +                       continue;
>> +
>> +               ret = devfreq_event_get_event(dmc->counter[i], &event);
>> +               if (ret < 0)
>> +                       return ret;
>> +
>> +               if (i % 3 != 2)
>> +                       continue;
>> +
>> +               *load_count += event.load_count;
>> +
>> +               if (total < event.total_count)
>> +                       total = event.total_count;
>> +       }
>> +
>> +       *total_count = total;
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_get_status() - Read current DMC performance statistics.
>> + * @dev:       device for which the statistics are requested
>> + * @stat:      structure which has statistic fields
>> + *
>> + * Function reads the DMC performance counters and calculates 'busy_time'
>> + * and 'total_time'. To protect from overflow, the values are shifted right
>> + * by 10. After read out the counters are setup to count again.
>> + */
>> +static int exynos5_dmc_get_status(struct device *dev,
>> +                                 struct devfreq_dev_status *stat)
>> +{
>> +       struct exynos5_dmc *dmc = dev_get_drvdata(dev);
>> +       unsigned long load, total;
>> +       int ret;
>> +       bool cnt_en;
>> +
>> +       mutex_lock(&dmc->lock);
>> +       cnt_en = dmc->counters_enabled;
>> +       mutex_unlock(&dmc->lock);
>> +       if (!cnt_en) {
>> +               dev_warn(dev, "performance counters needed, but not present\n");
>> +               return -EAGAIN;
>> +       }
>> +
>> +       ret = exynos5_counters_get(dmc, &load, &total);
>> +       if (ret < 0)
>> +               return -EINVAL;
>> +
>> +       /* To protect from overflow in calculation ratios, divide by 1024 */
>> +       stat->busy_time = load >> 10;
>> +       stat->total_time = total >> 10;
>> +
>> +       ret = exynos5_counters_set_event(dmc);
>> +       if (ret < 0) {
>> +               dev_err(dmc->dev, "could not set event counter\n");
>> +               return ret;
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_get_cur_freq() - Function returns current DMC frequency
>> + * @dev:       device for which the framework checks operating frequency
>> + * @freq:      returned frequency value
>> + *
>> + * It returns the currently used frequency of the DMC. The real operating
>> + * frequency might be lower when the clock source value could not be divided
>> + * to the requested value.
>> + */
>> +static int exynos5_dmc_get_cur_freq(struct device *dev, unsigned long *freq)
>> +{
>> +       struct exynos5_dmc *dmc = dev_get_drvdata(dev);
>> +
>> +       mutex_lock(&dmc->lock);
>> +       *freq = dmc->curr_rate;
>> +       mutex_unlock(&dmc->lock);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_df_profile - Devfreq governor's profile structure
>> + *
>> + * It provides to the devfreq framework needed functions and polling period.
>> + */
>> +static struct devfreq_dev_profile exynos5_dmc_df_profile = {
>> +       .polling_ms = 500,
>> +       .target = exynos5_dmc_target,
>> +       .get_dev_status = exynos5_dmc_get_status,
>> +       .get_cur_freq = exynos5_dmc_get_cur_freq,
>> +};
>> +
>> +/**
>> + * exynos5_dmc_align_initial_frequency() - Align initial frequency value
>> + * @dmc:       device for which the frequency is going to be set
>> + * @bootloader_init_freq:      initial frequency set by the bootloader in KHz
>> + *
>> + * The initial bootloader frequency, which is present during boot, might be
>> + * different that supported frequency values in the driver. It is possible
>> + * due to different PLL settings or used PLL as a source.
>> + * This function provides the 'initial_freq' for the devfreq framework
>> + * statistics engine which supports only registered values. Thus, some alignment
>> + * must be made.
>> + */
>> +unsigned long
>> +exynos5_dmc_align_init_freq(struct exynos5_dmc *dmc,
>> +                           unsigned long bootloader_init_freq)
>> +{
>> +       unsigned long aligned_freq;
>> +       int idx;
>> +
>> +       idx = find_target_freq_idx(dmc, bootloader_init_freq);
>> +       if (idx >= 0)
>> +               aligned_freq = dmc->opp[idx].freq_hz;
>> +       else
>> +               aligned_freq = dmc->opp[dmc->opp_count - 1].freq_hz;
>> +
>> +       return aligned_freq;
>> +}
>> +
>> +/**
>> + * create_timings_aligned() - Create register values and align with standard
>> + * @dmc:       device for which the frequency is going to be set
>> + * @idx:       speed bin in the OPP table
>> + * @clk_period_ps:     the period of the clock, known as tCK
>> + *
>> + * The function calculates timings and creates a register value ready for
>> + * a frequency transition. The register contains a few timings. They are
>> + * shifted by a known offset. The timing value is calculated based on memory
>> + * specyfication: minimal time required and minimal cycles required.
>> + */
>> +static int create_timings_aligned(struct exynos5_dmc *dmc, u32 *reg_timing_row,
>> +                                 u32 *reg_timing_data, u32 *reg_timing_power,
>> +                                 u32 clk_period_ps)
>> +{
>> +       u32 val;
>> +       struct timing_reg *reg;
>> +
>> +       if (clk_period_ps == 0)
>> +               return -EINVAL;
>> +
>> +       *reg_timing_row = 0;
>> +       *reg_timing_data = 0;
>> +       *reg_timing_power = 0;
>> +
>> +       val = dmc->timings->tRFC / clk_period_ps;
>> +       val += dmc->timings->tRFC % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tRFC);
>> +       reg = &timing_row[0];
>> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tRRD / clk_period_ps;
>> +       val += dmc->timings->tRRD % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tRRD);
>> +       reg = &timing_row[1];
>> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tRPab / clk_period_ps;
>> +       val += dmc->timings->tRPab % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tRPab);
>> +       reg = &timing_row[2];
>> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tRCD / clk_period_ps;
>> +       val += dmc->timings->tRCD % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tRCD);
>> +       reg = &timing_row[3];
>> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tRC / clk_period_ps;
>> +       val += dmc->timings->tRC % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tRC);
>> +       reg = &timing_row[4];
>> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tRAS / clk_period_ps;
>> +       val += dmc->timings->tRAS % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tRAS);
>> +       reg = &timing_row[5];
>> +       *reg_timing_row |= TIMING_VAL2REG(reg, val);
>> +
>> +       /* data related timings */
>> +       val = dmc->timings->tWTR / clk_period_ps;
>> +       val += dmc->timings->tWTR % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tWTR);
>> +       reg = &timing_data[0];
>> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tWR / clk_period_ps;
>> +       val += dmc->timings->tWR % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tWR);
>> +       reg = &timing_data[1];
>> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tRTP / clk_period_ps;
>> +       val += dmc->timings->tRTP % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tRTP);
>> +       reg = &timing_data[2];
>> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tW2W_C2C / clk_period_ps;
>> +       val += dmc->timings->tW2W_C2C % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tW2W_C2C);
>> +       reg = &timing_data[3];
>> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tR2R_C2C / clk_period_ps;
>> +       val += dmc->timings->tR2R_C2C % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tR2R_C2C);
>> +       reg = &timing_data[4];
>> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tWL / clk_period_ps;
>> +       val += dmc->timings->tWL % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tWL);
>> +       reg = &timing_data[5];
>> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tDQSCK / clk_period_ps;
>> +       val += dmc->timings->tDQSCK % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tDQSCK);
>> +       reg = &timing_data[6];
>> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tRL / clk_period_ps;
>> +       val += dmc->timings->tRL % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tRL);
>> +       reg = &timing_data[7];
>> +       *reg_timing_data |= TIMING_VAL2REG(reg, val);
>> +
>> +       /* power related timings */
>> +       val = dmc->timings->tFAW / clk_period_ps;
>> +       val += dmc->timings->tFAW % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tXP);
>> +       reg = &timing_power[0];
>> +       *reg_timing_power |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tXSR / clk_period_ps;
>> +       val += dmc->timings->tXSR % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tXSR);
>> +       reg = &timing_power[1];
>> +       *reg_timing_power |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tXP / clk_period_ps;
>> +       val += dmc->timings->tXP % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tXP);
>> +       reg = &timing_power[2];
>> +       *reg_timing_power |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tCKE / clk_period_ps;
>> +       val += dmc->timings->tCKE % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tCKE);
>> +       reg = &timing_power[3];
>> +       *reg_timing_power |= TIMING_VAL2REG(reg, val);
>> +
>> +       val = dmc->timings->tMRD / clk_period_ps;
>> +       val += dmc->timings->tMRD % clk_period_ps ? 1 : 0;
>> +       val = max(val, dmc->min_tck->tMRD);
>> +       reg = &timing_power[4];
>> +       *reg_timing_power |= TIMING_VAL2REG(reg, val);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * of_get_dram_timings() - helper function for parsing DT settings for DRAM
>> + * @dmc:        device for which the frequency is going to be set
>> + *
>> + * The function parses DT entries with DRAM information.
>> + */
>> +static int of_get_dram_timings(struct exynos5_dmc *dmc)
>> +{
>> +       int ret = 0;
>> +       struct device_node *np;
>> +       int idx;
>> +       struct device_node *np_ddr;
> 
> Combine with previous definition.
The 'np' will be removed.
> 
>> +       u32 freq_mhz, clk_period_ps;
>> +
>> +       np_ddr = of_parse_phandle(dmc->dev->of_node, "device-handle", 0);
>> +       if (!np_ddr) {
>> +               dev_warn(dmc->dev, "could not find 'device-handle' in DT\n");
>> +               return -EINVAL;
>> +       }
>> +
>> +       dmc->timing_row = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
>> +                                            sizeof(u32), GFP_KERNEL);
>> +       if (!dmc->timing_row)
>> +               return -ENOMEM;
>> +
>> +       dmc->timing_data = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
>> +                                             sizeof(u32), GFP_KERNEL);
>> +       if (!dmc->timing_data)
>> +               return -ENOMEM;
>> +
>> +       dmc->timing_power = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
>> +                                              sizeof(u32), GFP_KERNEL);
>> +       if (!dmc->timing_power)
>> +               return -ENOMEM;
>> +
>> +       dmc->timings = of_lpddr3_get_ddr_timings(np_ddr, dmc->dev,
>> +                                                DDR_TYPE_LPDDR3,
>> +                                                &dmc->timings_arr_size);
>> +       if (!dmc->timings) {
>> +               of_node_put(np_ddr);
>> +               dev_warn(dmc->dev, "could not get timings from DT\n");
>> +               return -EINVAL;
>> +       }
>> +
>> +       dmc->min_tck = of_lpddr3_get_min_tck(np_ddr, dmc->dev);
>> +       if (!dmc->min_tck) {
>> +               of_node_put(np_ddr);
>> +               dev_warn(dmc->dev, "could not get tck from DT\n");
>> +               return -EINVAL;
>> +       }
>> +
>> +       /* Sorted array of OPPs with frequency ascending */
>> +       for (idx = 0; idx < dmc->opp_count; idx++) {
>> +               freq_mhz = dmc->opp[idx].freq_hz / 1000000;
>> +               clk_period_ps = 1000000 / freq_mhz;
>> +
>> +               ret = create_timings_aligned(dmc, &dmc->timing_row[idx],
>> +                                            &dmc->timing_data[idx],
>> +                                            &dmc->timing_power[idx],
>> +                                            clk_period_ps);
>> +       }
>> +
>> +       of_node_put(np);
> 
> This looks weird. You do not assign np... or I missed something.
Right, it should be 'np_ddr'. I will fix it.
> 
>> +
>> +       /* Take the highest frequency's timings as 'bypass' */
>> +       dmc->bypass_timing_row = dmc->timing_row[idx - 1];
>> +       dmc->bypass_timing_data = dmc->timing_data[idx - 1];
>> +       dmc->bypass_timing_power = dmc->timing_power[idx - 1];
>> +
>> +       return ret;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_init_clks() - Initialize clocks needed for DMC operation.
>> + * @dev:       device for which the clocks are setup
>> + * @dmc:       DMC structure containing needed fields
>> + *
>> + * Get the needed clocks defined in DT device, enable and set the right parents.
>> + * Read current frequency and initialize the initial rate for governor.
>> + */
>> +static int exynos5_dmc_init_clks(struct device *dev, struct exynos5_dmc *dmc)
>> +{
>> +       int ret;
>> +       unsigned long target_volt = 0;
>> +       unsigned long target_rate = 0;
>> +
>> +       dmc->fout_spll = devm_clk_get(dev, "fout_spll");
>> +       if (IS_ERR(dmc->fout_spll))
>> +               return PTR_ERR(dmc->fout_spll);
>> +
>> +       dmc->fout_bpll = devm_clk_get(dev, "fout_bpll");
>> +       if (IS_ERR(dmc->fout_bpll))
>> +               return PTR_ERR(dmc->fout_bpll);
>> +
>> +       dmc->mout_mclk_cdrex = devm_clk_get(dev, "mout_mclk_cdrex");
>> +       if (IS_ERR(dmc->mout_mclk_cdrex))
>> +               return PTR_ERR(dmc->mout_mclk_cdrex);
>> +
>> +       dmc->mout_bpll = devm_clk_get(dev, "mout_bpll");
>> +       if (IS_ERR(dmc->mout_bpll))
>> +               return PTR_ERR(dmc->mout_bpll);
>> +
>> +       dmc->mout_mx_mspll_ccore = devm_clk_get(dev, "mout_mx_mspll_ccore");
>> +       if (IS_ERR(dmc->mout_mx_mspll_ccore))
>> +               return PTR_ERR(dmc->mout_mx_mspll_ccore);
>> +
>> +       dmc->dout_clk2x_phy0 = devm_clk_get(dev, "dout_clk2x_phy0");
>> +       if (IS_ERR(dmc->dout_clk2x_phy0))
>> +               return PTR_ERR(dmc->dout_clk2x_phy0);
>> +
>> +       dmc->mout_spll = devm_clk_get(dev, "ff_dout_spll2");
>> +       if (IS_ERR(dmc->mout_spll)) {
>> +               dmc->mout_spll = devm_clk_get(dev, "mout_sclk_spll");
>> +               if (IS_ERR(dmc->mout_spll))
>> +                       return PTR_ERR(dmc->mout_spll);
>> +       }
>> +
>> +       /*
>> +        * Convert frequency to KHz values and set it for the governor.
>> +        */
>> +       dmc->curr_rate = clk_get_rate(dmc->mout_mclk_cdrex);
>> +       dmc->curr_rate = exynos5_dmc_align_init_freq(dmc, dmc->curr_rate);
>> +       exynos5_dmc_df_profile.initial_freq = dmc->curr_rate;
>> +
>> +       ret = exynos5_dmc_get_volt_freq(dev, &dmc->curr_rate, &target_rate,
>> +                                       &target_volt, 0);
>> +       if (ret)
>> +               return ret;
>> +
>> +       dmc->curr_volt = target_volt;
>> +
>> +       clk_prepare_enable(dmc->mout_spll);
>> +       clk_set_parent(dmc->mout_mx_mspll_ccore, dmc->mout_spll);
>> +       clk_prepare_enable(dmc->mout_mx_mspll_ccore);
>> +
>> +       dmc->bypass_rate = clk_get_rate(dmc->mout_mx_mspll_ccore);
>> +
>> +       clk_prepare_enable(dmc->fout_bpll);
>> +       clk_prepare_enable(dmc->mout_bpll);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * exynos5_performance_counters_init() - Initializes performance DMC's counters
>> + * @dmc:       DMC for which it does the setup
>> + *
>> + * Initialization of performance counters in DMC for estimating usage.
>> + * The counter's values are used for calculation of a memory bandwidth and based
>> + * on that the governor changes the frequency.
>> + * The counters are not used when the governor is GOVERNOR_USERSPACE.
>> + */
>> +static int exynos5_performance_counters_init(struct exynos5_dmc *dmc)
>> +{
>> +       int counters_size;
>> +       int ret, i;
>> +
>> +       dmc->num_counters = devfreq_event_get_edev_count(dmc->dev);
>> +       if (dmc->num_counters < 0) {
>> +               dev_err(dmc->dev, "could not get devfreq-event counters\n");
>> +               return dmc->num_counters;
>> +       }
>> +
>> +       counters_size = sizeof(struct devfreq_event_dev) * dmc->num_counters;
>> +       dmc->counter = devm_kzalloc(dmc->dev, counters_size, GFP_KERNEL);
>> +       if (!dmc->counter)
>> +               return -ENOMEM;
>> +
>> +       for (i = 0; i < dmc->num_counters; i++) {
>> +               dmc->counter[i] =
>> +                       devfreq_event_get_edev_by_phandle(dmc->dev, i);
>> +               if (IS_ERR_OR_NULL(dmc->counter[i]))
>> +                       return -EPROBE_DEFER;
>> +       }
>> +
>> +       ret = exynos5_counters_enable_edev(dmc);
>> +       if (ret < 0) {
>> +               dev_err(dmc->dev, "could not enable event counter\n");
>> +               return ret;
>> +       }
>> +
>> +       ret = exynos5_counters_set_event(dmc);
>> +       if (ret < 0) {
>> +               dev_err(dmc->dev, "counld not set event counter\n");
>> +               return ret;
>> +       }
>> +
>> +       mutex_lock(&dmc->lock);
>> +       dmc->counters_enabled = true;
> 
> I do not think it is useful (counters_enabled == false cannot happen).
> You call this function before registering devfreq.
Yes, in this implementation the counters_enabled are not needed.
It will be removed in the next version.
> 
>> +       mutex_unlock(&dmc->lock);
>> +
>> +       return 0;
>> +}
>> +
>> +static struct regmap_config exynos5_clk_regmap_cfg = {
>> +       .reg_bits = 32,
>> +       .val_bits = 32,
>> +       .reg_stride = 4,
>> +};
>> +
>> +static int exynos5_dmc_init_clk_regmap(struct platform_device *pdev,
>> +                                      struct exynos5_dmc *dmc)
>> +{
>> +       struct resource *res;
>> +       void __iomem *base;
>> +
>> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
>> +       base = devm_ioremap_resource(dmc->dev, res);
>> +       if (IS_ERR(base))
>> +               return PTR_ERR(base);
>> +
>> +       exynos5_clk_regmap_cfg.max_register = resource_size(res) - 4;
>> +       dmc->clk_regmap = devm_regmap_init_mmio(dmc->dev, base,
>> +                                            &exynos5_clk_regmap_cfg);
>> +       if (IS_ERR(dmc->clk_regmap))
>> +               return PTR_ERR(dmc->clk_regmap);
>> +
>> +       return 0;
>> +}
>> +
>> +#ifdef CONFIG_DEBUG_FS
>> +
>> +static int dmc_dbg_show_timings(struct seq_file *seq, void *na)
>> +{
>> +       struct exynos5_dmc *dmc = seq->private;
>> +       int i, j;
>> +       u32 val;
>> +       struct timing_reg *reg;
>> +
>> +       seq_printf(seq, "timings for each frequency\n");
>> +       for (j = dmc->opp_count - 1; j >= 0; j--) {
>> +               seq_printf(seq, "frequency = %uMHz\n",
>> +                                  dmc->opp[j].freq_hz / 1000000);
>> +               seq_printf(seq, "timing_row, timing_data, timing_power\n");
>> +               seq_printf(seq, "0x%08X, 0x%08X, 0x%08X\n", dmc->timing_row[j],
>> +                          dmc->timing_data[j], dmc->timing_power[j]);
>> +       }
>> +
>> +       for (j = dmc->opp_count - 1; j >= 0; j--) {
>> +               seq_printf(seq, "frequency [MHz] = %u\n",
>> +                                  dmc->opp[j].freq_hz / 1000000);
>> +
>> +               for (i = 0; i < ARRAY_SIZE(timing_row); i++) {
>> +                       reg = &timing_row[i];
>> +                       val = TIMING_REG2VAL(dmc->timing_row[j], reg);
>> +                       seq_printf(seq, "%s = %u\n", reg->name, val);
>> +               }
>> +
>> +               for (i = 0; i < ARRAY_SIZE(timing_data); i++) {
>> +                       reg = &timing_data[i];
>> +                       val = TIMING_REG2VAL(dmc->timing_data[j], reg);
>> +                       seq_printf(seq, "%s = %u\n", reg->name, val);
>> +               }
>> +
>> +               for (i = 0; i < ARRAY_SIZE(timing_power); i++) {
>> +                       reg = &timing_power[i];
>> +                       val = TIMING_REG2VAL(dmc->timing_power[j], reg);
>> +                       seq_printf(seq, "%s = %u\n", reg->name, val);
>> +               }
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +static int dmc_dbg_open_timings(struct inode *inode, struct file *f)
>> +{
>> +       return single_open(f, dmc_dbg_show_timings, inode->i_private);
>> +}
>> +
>> +static const char *event_get_name(const char *evt)
>> +{
>> +       int i;
>> +
>> +       for (i = 0; i < ARRAY_SIZE(event_name); i += 2) {
>> +               if (!strcmp(event_name[i], evt))
>> +                       return event_name[i + 1];
>> +       }
>> +
>> +       return "Unknown";
>> +}
>> +
>> +static int dmc_dbg_show_cnt(struct seq_file *seq, void *na)
>> +{
>> +       struct exynos5_dmc *dmc = seq->private;
>> +       int i;
>> +       struct devfreq_event_data event;
>> +       struct devfreq_event_dev *edev;
>> +       int ret;
>> +       const char *evt_name;
>> +       u64 ts_new, delta;
>> +       static u64 ts;
>> +
>> +       seq_printf(seq, "Performance based on PMU counters\n");
>> +       seq_printf(seq, "The counters could overflow every ~9.2 sec\n");
>> +
>> +       ts_new = ktime_get_ns();
>> +       delta = ts_new - ts;
>> +
>> +       for (i = 0; i < dmc->num_counters; i++) {
>> +               edev = dmc->counter[i];
>> +               if (!edev)
>> +                       continue;
>> +
>> +               evt_name = event_get_name(edev->desc->name);
>> +
>> +               ret = devfreq_event_get_event(edev, &event);
>> +               if (ret < 0)
>> +                       return ret;
>> +
>> +               seq_printf(seq, "%s = %lu / %lu\n", evt_name, event.load_count,
>> +                          event.total_count);
>> +       }
>> +
>> +       seq_printf(seq, "For last %llu ms\n",
>> +                  div64_u64(delta, 1000000UL));
>> +
>> +       ts = ktime_get_ns();
>> +       ret = exynos5_counters_set_event(dmc);
>> +       if (ret < 0) {
>> +               dev_err(dmc->dev, "could not set event counter\n");
>> +               return ret;
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +static int dmc_dbg_open_cnt(struct inode *inode, struct file *f)
>> +{
>> +       return single_open(f, dmc_dbg_show_cnt, inode->i_private);
>> +}
>> +
>> +struct counter {
>> +       u64 load;
>> +       u64 total;
>> +};
>> +
>> +static int dmc_dbg_show_cnt_100ms(struct seq_file *seq, void *na)
>> +{
>> +       struct exynos5_dmc *dmc = seq->private;
>> +       int i;
>> +       u64 bandwidth = 0;
>> +       struct devfreq_event_data event;
>> +       struct devfreq_event_dev *edev;
>> +       int ret;
>> +       const char *evt_name;
>> +       u64 ts_new, delta;
>> +       static u64 ts;
>> +       struct counter *cnt;
>> +       u64 total[3] = {0, 0, 0 }; /* read, write, read+write data*/
>> +       const char *type[3] = {"read", "write", "read+write"};
>> +       u64 bus_cyc_count = 0;
>> +       int offset = 0;
>> +       char *s;
>> +
>> +       s = kzalloc(PAGE_SIZE * sizeof(char), GFP_KERNEL);
>> +       if (!s)
>> +               return -ENOMEM;
>> +
>> +       cnt = kcalloc(dmc->num_counters, sizeof(struct counter), GFP_KERNEL);
>> +       if (!cnt)
>> +               return -ENOMEM;
>> +
>> +       ret = exynos5_counters_set_event(dmc);
>> +       if (ret < 0) {
>> +               dev_err(dmc->dev, "could not set event counter\n");
>> +               return ret;
>> +       }
>> +
>> +       ts = ktime_get_ns();
>> +       msleep(100);
>> +
>> +       /* Seprate data acquisition from presentation due to some
>> +          overheads. */
>> +       for (i = 0; i < dmc->num_counters; i++) {
>> +               edev = dmc->counter[i];
>> +               if (!edev)
>> +                       continue;
>> +
>> +               ret = devfreq_event_get_event(edev, &event);
>> +               if (ret < 0)
>> +                       return ret;
>> +
>> +               total[i % 3] += event.load_count;
>> +               cnt[i].load = event.load_count;
>> +               cnt[i].total = event.total_count;
>> +
>> +               if (bus_cyc_count < event.total_count)
>> +                       bus_cyc_count = event.total_count;
>> +       }
>> +
>> +       ts_new = ktime_get_ns();
>> +       delta = ts_new - ts;
>> +       if (delta == 0)
>> +               delta = 1;
>> +
>> +       for (i = 0; i < dmc->num_counters; i++) {
>> +               edev = dmc->counter[i];
>> +               if (!edev)
>> +                       continue;
>> +
>> +               evt_name = event_get_name(edev->desc->name);
>> +
>> +               bandwidth = (u64)cnt[i].load * AXI_BUS_WIDTH_BYTES * 1000;
>> +               bandwidth = div64_u64(bandwidth, delta);
>> +
>> +               offset += sprintf(s + offset, "%s\t\t%llu MB/s\n",
>> +                                 evt_name, bandwidth);
>> +       }
>> +
>> +       for (i = 0; i < 3; i++) {
>> +               bandwidth = (u64)total[i] * AXI_BUS_WIDTH_BYTES * 1000;
>> +               bandwidth = div64_u64(bandwidth, delta);
>> +
>> +               offset += sprintf(s + offset, "total\t%s\t\t%llu MB/s\n",
>> +                                 type[i], bandwidth);
>> +       }
>> +
>> +       /* AXI speed is presented in MHz*/
>> +       bus_cyc_count *= 1000;
>> +
>> +       seq_printf(seq, "Performance based on PMU counters\n");
>> +       seq_printf(seq, "The counters will overflow every ~9.2 sec\n");
>> +       seq_printf(seq, "%s", s);
>> +       seq_printf(seq, "AXI bus frequency %llu MHz, width %u B, SDR mode\n",
>> +                  div64_u64(bus_cyc_count, delta), AXI_BUS_WIDTH_BYTES);
>> +       seq_printf(seq, "For last %llu ms\n",
>> +                  div64_u64(delta, 1000000UL));
>> +
>> +       kfree(cnt);
>> +       kfree(s);
>> +
>> +       return 0;
>> +}
>> +
>> +static int dmc_dbg_show_cnt_100ms_raw(struct seq_file *seq, void *na)
>> +{
>> +       struct exynos5_dmc *dmc = seq->private;
>> +       int i;
>> +       struct devfreq_event_data event;
>> +       struct devfreq_event_dev *edev;
>> +       int ret;
>> +       const char *evt_name;
>> +       u64 ts_new, delta;
>> +       static u64 ts;
>> +       struct counter *cnt;
>> +       const char *type[3] = {"read", "write", "read+write"};
>> +       int offset = 0;
>> +       char *s;
>> +
>> +       s = kzalloc(PAGE_SIZE * sizeof(char), GFP_KERNEL);
>> +       if (!s)
>> +               return -ENOMEM;
>> +
>> +       cnt = kcalloc(dmc->num_counters, sizeof(struct counter), GFP_KERNEL);
>> +       if (!cnt)
>> +               return -ENOMEM;
>> +
>> +       ret = exynos5_counters_set_event(dmc);
>> +       if (ret < 0) {
>> +               dev_err(dmc->dev, "could not set event counter\n");
>> +               return ret;
>> +       }
>> +
>> +       ts = ktime_get_ns();
>> +       msleep(100);
>> +
>> +       /* Seprate data acquisition from presentation due to some
>> +          overheads. */
>> +       for (i = 0; i < dmc->num_counters; i++) {
>> +               edev = dmc->counter[i];
>> +               if (!edev)
>> +                       continue;
>> +
>> +               ret = devfreq_event_get_event(edev, &event);
>> +               if (ret < 0)
>> +                       return ret;
>> +
>> +               cnt[i].load = event.load_count;
>> +               cnt[i].total = event.total_count;
>> +       }
>> +
>> +       ts_new = ktime_get_ns();
>> +       delta = ts_new - ts;
>> +       if (delta == 0)
>> +               delta = 1;
>> +
>> +       for (i = 0; i < dmc->num_counters; i++) {
>> +               edev = dmc->counter[i];
>> +               if (!edev)
>> +                       continue;
>> +
>> +               evt_name = event_get_name(edev->desc->name);
>> +
>> +               offset += sprintf(s + offset, "%s (%s)\t\t%llu / %llu\n",
>> +                                 evt_name, type[i % 3], cnt[i].load,
>> +                                 cnt[i].total);
>> +       }
>> +
>> +       seq_printf(seq, "Performance based on PMU counters ('load'/'total')\n");
>> +       seq_printf(seq, "The counters will overflow every ~9.2 sec\n");
>> +       seq_printf(seq, "%s", s);
>> +       seq_printf(seq, "For last %llu ms\n",
>> +                  div64_u64(delta, 1000000UL));
>> +
>> +       kfree(cnt);
>> +       kfree(s);
>> +
>> +       return 0;
>> +}
>> +
>> +static int dmc_dbg_open_cnt_100ms(struct inode *inode, struct file *f)
>> +{
>> +       return single_open(f, dmc_dbg_show_cnt_100ms, inode->i_private);
>> +}
>> +
>> +static int dmc_dbg_open_cnt_100ms_raw(struct inode *inode, struct file *f)
>> +{
>> +       return single_open(f, dmc_dbg_show_cnt_100ms_raw, inode->i_private);
>> +}
>> +
>> +static const struct file_operations dmc_debugfs_ops_timings = {
>> +       .open = dmc_dbg_open_timings,
>> +       .read = seq_read,
>> +       .release = single_release,
>> +};
>> +
>> +static const struct file_operations dmc_debugfs_ops_cnt = {
>> +       .open = dmc_dbg_open_cnt,
>> +       .read = seq_read,
>> +       .release = single_release,
>> +};
>> +
>> +static const struct file_operations dmc_debugfs_ops_cnt_100ms = {
>> +       .open = dmc_dbg_open_cnt_100ms,
>> +       .read = seq_read,
>> +       .release = single_release,
>> +};
>> +
>> +static const struct file_operations dmc_debugfs_ops_cnt_100ms_raw = {
>> +       .open = dmc_dbg_open_cnt_100ms_raw,
>> +       .read = seq_read,
>> +       .release = single_release,
>> +};
>> +
>> +static void exynos5_dmc_debugfs_init(struct exynos5_dmc *dmc)
>> +{
>> +       struct dentry *dentry;
>> +
>> +       dmc->dbg_root = debugfs_create_dir(dev_name(dmc->dev), NULL);
>> +       if (!dmc->dbg_root)
>> +               return;
>> +
>> +       dentry = debugfs_create_file("timings", 0444, dmc->dbg_root, dmc,
>> +                                    &dmc_debugfs_ops_timings);
>> +       if (!dentry)
>> +               goto clean_debugfs;
>> +
>> +       dentry = debugfs_create_file("counters", 0444, dmc->dbg_root, dmc,
>> +                                    &dmc_debugfs_ops_cnt);
>> +       if (!dentry)
>> +               goto clean_debugfs;
>> +
>> +       dentry = debugfs_create_file("100ms_counters", 0444, dmc->dbg_root, dmc,
>> +                                    &dmc_debugfs_ops_cnt_100ms);
>> +       if (!dentry)
>> +               goto clean_debugfs;
>> +
>> +       dentry = debugfs_create_file("100ms_raw_counters", 0444, dmc->dbg_root,
>> +                                    dmc, &dmc_debugfs_ops_cnt_100ms_raw);
>> +       if (!dentry)
>> +               goto clean_debugfs;
>> +
>> +       return;
>> +
>> +clean_debugfs:
>> +       debugfs_remove_recursive(dmc->dbg_root);
>> +}
>> +#else
>> +static void exynos5_dmc_debugfs_init(struct exynos5_dmc *dmc)
>> +{}
>> +#endif
>> +
>> +/**
>> + * exynos5_dmc_set_pause_on_switching() - Controls a pause feature in DMC
>> + * @dmc:       device which is used for changing this feature
>> + * @set:       a boolean state passing enable/disable request
>> + *
>> + * There is a need of pausing DREX DMC when divider or MUX in clock tree
>> + * changes its configuration. In such situation access to the memory is blocked
>> + * in DMC automatically. This feature is used when clock frequency change
>> + * request appears and touches clock tree.
>> + */
>> +static inline int exynos5_dmc_set_pause_on_switching(struct exynos5_dmc *dmc)
>> +{
>> +       unsigned int val;
>> +       int ret;
>> +
>> +       ret = regmap_read(dmc->clk_regmap, CDREX_PAUSE, &val);
>> +       if (ret)
>> +               return ret;
>> +
>> +       val |= 1UL;
>> +       regmap_write(dmc->clk_regmap, CDREX_PAUSE, val);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_probe() - Probe function for the DMC driver
>> + * @pdev:      platform device for which the driver is going to be initialized
>> + *
>> + * Initialize basic components: clocks, regulators, performance counters, etc.
>> + * Read out product version and based on the information setup
>> + * internal structures for the controller (frequency and voltage) and for DRAM
>> + * memory parameters: timings for each operating frequency.
>> + * Register new devfreq device for controlling DVFS of the DMC.
>> + */
>> +static int exynos5_dmc_probe(struct platform_device *pdev)
>> +{
>> +       int ret = 0;
>> +       struct exynos5_dmc *dmc;
>> +       struct device *dev = &pdev->dev;
>> +       struct resource *res;
>> +
>> +       dmc = devm_kzalloc(dev, sizeof(*dmc), GFP_KERNEL);
>> +       if (!dmc)
>> +               return -ENOMEM;
>> +
>> +       mutex_init(&dmc->lock);
>> +
>> +       dmc->dev = dev;
>> +       platform_set_drvdata(pdev, dmc);
>> +
>> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> +       dmc->base_drexi0 = devm_ioremap_resource(dev, res);
>> +       if (IS_ERR(dmc->base_drexi0))
>> +               return PTR_ERR(dmc->base_drexi0);
>> +
>> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
>> +       dmc->base_drexi1 = devm_ioremap_resource(dev, res);
>> +       if (IS_ERR(dmc->base_drexi1))
>> +               return PTR_ERR(dmc->base_drexi1);
>> +
>> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
>> +       dmc->chip_id = devm_ioremap_resource(dev, res);
>> +       if (IS_ERR(dmc->chip_id))
>> +               return PTR_ERR(dmc->chip_id);
>> +
>> +       ret = exynos5_dmc_chip_revision_settings(dmc);
>> +       if (ret)
>> +               return ret;
>> +
>> +       ret = exynos5_init_freq_table(dev, dmc, &exynos5_dmc_df_profile);
>> +       if (ret) {
>> +               dev_warn(dev, "couldn't initialize frequency settings\n");
>> +               return ret;
>> +       }
>> +
>> +       dmc->vdd_mif = devm_regulator_get(dev, "vdd");
>> +       if (IS_ERR(dmc->vdd_mif)) {
>> +               ret = PTR_ERR(dmc->vdd_mif);
>> +               dev_warn(dev, "couldn't get regulator\n");
>> +               return ret;
>> +       }
>> +
>> +       ret = exynos5_dmc_init_clks(dev, dmc);
>> +       if (ret) {
>> +               dev_warn(dev, "couldn't initialize clocks\n");
>> +               return ret;
>> +       }
>> +
>> +       ret = exynos5_dmc_init_clk_regmap(pdev, dmc);
>> +       if (ret) {
>> +               dev_warn(dev, "couldn't initialize clock regmap\n");
>> +               return ret;
>> +       }
>> +
>> +       ret = of_get_dram_timings(dmc);
>> +       if (ret) {
>> +               dev_warn(dev, "couldn't initialize timings settings\n");
>> +               return ret;
>> +       }
>> +
>> +       ret = exynos5_performance_counters_init(dmc);
>> +       if (ret) {
>> +               dev_warn(dev, "couldn't probe performance counters\n");
>> +               goto remove_clocks;
>> +       }
>> +
>> +       ret = exynos5_dmc_set_pause_on_switching(dmc);
>> +       if (ret) {
>> +               dev_warn(dev, "couldn't get access to PAUSE register\n");
>> +               goto remove_clocks;
>> +       }
>> +
>> +
>> +       /*
>> +        * Setup default thresholds for the devfreq governor.
>> +        * The values are chosen based on experiments.
>> +        */
>> +       dmc->gov_data.upthreshold = 30;
>> +       dmc->gov_data.downdifferential = 5;
>> +
>> +       dmc->df = devm_devfreq_add_device(dev, &exynos5_dmc_df_profile,
>> +                                         DEVFREQ_GOV_USERSPACE,
>> +                                         &dmc->gov_data);
>> +
>> +       if (IS_ERR(dmc->df)) {
>> +               ret = PTR_ERR(dmc->df);
>> +               goto err_devfreq_add;
>> +       }
>> +
>> +       exynos5_dmc_debugfs_init(dmc);
>> +
>> +       dev_info(&pdev->dev, "DMC init for prod_id=0x%08x pkg_id=0x%08x\n",
>> +                dmc->prod_rev, dmc->pkg_rev);
>> +
>> +       return 0;
>> +
>> +err_devfreq_add:
>> +       exynos5_counters_disable_edev(dmc);
>> +remove_clocks:
>> +       clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
>> +       clk_disable_unprepare(dmc->mout_spll);
>> +
>> +       return ret;
>> +}
>> +
>> +/**
>> + * exynos5_dmc_remove() - Remove function for the platform device
>> + * @pdev:      platform device which is going to be removed
>> + *
>> + * The function relies on 'devm' framework function which automatically
>> + * clean the device's resources. It just calls explicitly disable function for
>> + * the performance counters.
>> + */
>> +static int exynos5_dmc_remove(struct platform_device *pdev)
>> +{
>> +       struct exynos5_dmc *dmc = dev_get_drvdata(&pdev->dev);
>> +
>> +       exynos5_counters_disable_edev(dmc);
>> +
>> +       clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
>> +       clk_disable_unprepare(dmc->mout_spll);
>> +
>> +       dev_pm_opp_remove_table(&pdev->dev);
>> +
>> +       dev_info(&pdev->dev, "DMC removed\n");
>> +
>> +       return 0;
>> +}
>> +
>> +static const struct of_device_id exynos5_dmc_of_match[] = {
>> +       { .compatible = "samsung,exynos5422-dmc", },
>> +       { },
>> +};
>> +MODULE_DEVICE_TABLE(of, exynos5_dmc_of_match);
>> +
>> +static struct platform_driver exynos5_dmc_platdrv = {
>> +       .probe  = exynos5_dmc_probe,
>> +       .remove = exynos5_dmc_remove,
>> +       .driver = {
>> +               .name   = "exynos5-dmc",
>> +               .of_match_table = exynos5_dmc_of_match,
>> +       },
>> +};
>> +module_platform_driver(exynos5_dmc_platdrv);
>> +MODULE_DESCRIPTION("Driver for Exynos5422 Dynamic Memory Controller dynamic frequency and voltage change"
> 
> Unneeded empty line.
I agree.

Thank you Krzysztof for the review. I will wait for Rob's feedback
regarding the 'max-freq' --> 'reg' in the DT node and will send new
patches.

Regards,
Lukasz
> 
> Best regards,
> Krzysztof
> 
> 

[PATCH v6 08/10] drivers: devfreq: events: add Exynos PPMU new events

[Lukasz Luba]

Define new performance events supported by Exynos5422 SoC counters.
The counters are built-in in Dynamic Memory Controller and provide
information regarding memory utilization.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 drivers/devfreq/event/exynos-ppmu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/devfreq/event/exynos-ppmu.c b/drivers/devfreq/event/exynos-ppmu.c
index 073bf2c..dca97ca 100644
--- a/drivers/devfreq/event/exynos-ppmu.c
+++ b/drivers/devfreq/event/exynos-ppmu.c
@@ -89,6 +89,12 @@ static struct __exynos_ppmu_events {
 	PPMU_EVENT(d1-cpu),
 	PPMU_EVENT(d1-general),
 	PPMU_EVENT(d1-rt),
+
+	/* For Exynos5422 SoC */
+	PPMU_EVENT(dmc0_0),
+	PPMU_EVENT(dmc0_1),
+	PPMU_EVENT(dmc1_0),
+	PPMU_EVENT(dmc1_1),
 };
 
 static int exynos_ppmu_find_ppmu_id(struct devfreq_event_dev *edev)
-- 
2.7.4

[PATCH v6 09/10] ARM: dts: exynos: add DMC device for exynos5422

[Lukasz Luba]

Add description of Dynamic Memory Controller and PPMU counters.
They are used by exynos5422-dmc driver.
There is a definition of the memory chip, hwich is then used during
calculation of timings for each OPP.
The algorithm in the driver needs these two sets to bound the timings.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 arch/arm/boot/dts/exynos5420.dtsi             | 120 ++++++++++++++++++++++++++
 arch/arm/boot/dts/exynos5422-odroid-core.dtsi | 120 ++++++++++++++++++++++++++
 2 files changed, 240 insertions(+)

diff --git a/arch/arm/boot/dts/exynos5420.dtsi b/arch/arm/boot/dts/exynos5420.dtsi
index aaff158..b687cd7 100644
--- a/arch/arm/boot/dts/exynos5420.dtsi
+++ b/arch/arm/boot/dts/exynos5420.dtsi
@@ -14,6 +14,7 @@
 #include <dt-bindings/clock/exynos5420.h>
 #include <dt-bindings/clock/exynos-audss-clk.h>
 #include <dt-bindings/interrupt-controller/arm-gic.h>
+#include <dt-bindings/pmu/exynos_ppmu.h>
 
 / {
 	compatible = "samsung,exynos5420", "samsung,exynos5";
@@ -235,6 +236,37 @@
 			status = "disabled";
 		};
 
+		dmc: memory-controller@10c20000 {
+			compatible = "samsung,exynos5422-dmc";
+			reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
+				<0x10000000 0x1000>, <0x10030000 0x1000>;
+			clocks = <&clock CLK_FOUT_SPLL>,
+				 <&clock CLK_MOUT_SCLK_SPLL>,
+				 <&clock CLK_FF_DOUT_SPLL2>,
+				 <&clock CLK_FOUT_BPLL>,
+				 <&clock CLK_MOUT_BPLL>,
+				 <&clock CLK_SCLK_BPLL>,
+				 <&clock CLK_MOUT_MX_MSPLL_CCORE>,
+				 <&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
+				 <&clock CLK_MOUT_MCLK_CDREX>,
+				 <&clock CLK_DOUT_CLK2X_PHY0>,
+				 <&clock CLK_CLKM_PHY0>,
+				 <&clock CLK_CLKM_PHY1>;
+			clock-names = "fout_spll",
+				      "mout_sclk_spll",
+				      "ff_dout_spll2",
+				      "fout_bpll",
+				      "mout_bpll",
+				      "sclk_bpll",
+				      "mout_mx_mspll_ccore",
+				      "mout_mx_mspll_ccore_phy",
+				      "mout_mclk_cdrex",
+				      "dout_clk2x_phy0",
+				      "clkm_phy0",
+				      "clkm_phy1";
+			status = "disabled";
+		};
+
 		nocp_mem0_0: nocp@10ca1000 {
 			compatible = "samsung,exynos5420-nocp";
 			reg = <0x10CA1000 0x200>;
@@ -271,6 +303,94 @@
 			status = "disabled";
 		};
 
+		ppmu_dmc0_0: ppmu@10d00000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x10d00000 0x2000>;
+			clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
+			clock-names = "ppmu";
+			events {
+				ppmu_event0_dmc0_0: ppmu-event0-dmc0_0 {
+					event-name = "ppmu-event0-dmc0_0";
+					event-data-type = <PPMU_RO_DATA_CNT>;
+				};
+				ppmu_event1_dmc0_0: ppmu-event1-dmc0_0 {
+					event-name = "ppmu-event1-dmc0_0";
+					event-data-type = <PPMU_WO_DATA_CNT>;
+				};
+				ppmu_event3_dmc0_0: ppmu-event3-dmc0_0 {
+					event-name = "ppmu-event3-dmc0_0";
+					event-data-type = <(PPMU_RO_DATA_CNT |
+						PPMU_WO_DATA_CNT)>;
+				};
+			};
+		};
+
+		ppmu_dmc0_1: ppmu@10d10000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x10d10000 0x2000>;
+			clocks = <&clock CLK_PCLK_PPMU_DREX0_1>;
+			clock-names = "ppmu";
+			events {
+				ppmu_event0_dmc0_1: ppmu-event0-dmc0_1 {
+					event-name = "ppmu-event0-dmc0_1";
+					event-data-type = <PPMU_RO_DATA_CNT>;
+				};
+				ppmu_event1_dmc0_1: ppmu-event1-dmc0_1 {
+					event-name = "ppmu-event1-dmc0_1";
+					event-data-type = <PPMU_WO_DATA_CNT>;
+				};
+				ppmu_event3_dmc0_1: ppmu-event3-dmc0_1 {
+					event-name = "ppmu-event3-dmc0_1";
+					event-data-type = <(PPMU_RO_DATA_CNT |
+						PPMU_WO_DATA_CNT)>;
+				};
+			};
+		};
+
+		ppmu_dmc1_0: ppmu@10d60000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x10d60000 0x2000>;
+			clocks = <&clock CLK_PCLK_PPMU_DREX1_0>;
+			clock-names = "ppmu";
+			events {
+				ppmu_event0_dmc1_0: ppmu-event0-dmc1_0 {
+					event-name = "ppmu-event0-dmc1_0";
+					event-data-type = <PPMU_RO_DATA_CNT>;
+				};
+				ppmu_event1_dmc1_0: ppmu-event1-dmc1_0 {
+					event-name = "ppmu-event1-dmc1_0";
+					event-data-type = <PPMU_WO_DATA_CNT>;
+				};
+				ppmu_event3_dmc1_0: ppmu-event3-dmc1_0 {
+					event-name = "ppmu-event3-dmc1_0";
+					event-data-type = <(PPMU_RO_DATA_CNT |
+						PPMU_WO_DATA_CNT)>;
+				};
+			};
+		};
+
+		ppmu_dmc1_1: ppmu@10d70000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x10d70000 0x2000>;
+			clocks = <&clock CLK_PCLK_PPMU_DREX1_1>;
+			clock-names = "ppmu";
+			events {
+				ppmu_event0_dmc1_1: ppmu-event0-dmc1_1 {
+					event-name = "ppmu-event0-dmc1_1";
+					event-data-type = <PPMU_RO_DATA_CNT>;
+				};
+				ppmu_event1_dmc1_1: ppmu-event1-dmc1_1 {
+					event-name = "ppmu-event1-dmc1_1";
+					event-data-type = <PPMU_WO_DATA_CNT>;
+				};
+				ppmu_event3_dmc1_1: ppmu-event3-dmc1_1 {
+					event-name = "ppmu-event3-dmc1_1";
+					event-data-type = <(PPMU_RO_DATA_CNT |
+						PPMU_WO_DATA_CNT)>;
+				};
+			};
+		};
+
 		gsc_pd: power-domain@10044000 {
 			compatible = "samsung,exynos4210-pd";
 			reg = <0x10044000 0x20>;
diff --git a/arch/arm/boot/dts/exynos5422-odroid-core.dtsi b/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
index 25d95de1..76bf0dbf 100644
--- a/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
+++ b/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
@@ -34,6 +34,95 @@
 			clock-frequency = <24000000>;
 		};
 	};
+
+	dmc_opp_table: opp_table2 {
+		compatible = "operating-points-v2";
+
+		opp00 {
+			opp-hz = /bits/ 64 <165000000>;
+			opp-microvolt = <875000>;
+		};
+		opp01 {
+			opp-hz = /bits/ 64 <206000000>;
+			opp-microvolt = <875000>;
+		};
+		opp02 {
+			opp-hz = /bits/ 64 <275000000>;
+			opp-microvolt = <875000>;
+		};
+		opp03 {
+			opp-hz = /bits/ 64 <413000000>;
+			opp-microvolt = <887500>;
+		};
+		opp04 {
+			opp-hz = /bits/ 64 <543000000>;
+			opp-microvolt = <937500>;
+		};
+		opp05 {
+			opp-hz = /bits/ 64 <633000000>;
+			opp-microvolt = <1012500>;
+		};
+		opp06 {
+			opp-hz = /bits/ 64 <728000000>;
+			opp-microvolt = <1037500>;
+		};
+		opp07 {
+			opp-hz = /bits/ 64 <825000000>;
+			opp-microvolt = <1050000>;
+		};
+	};
+
+	samsung_K3QF2F20DB: lpddr3 {
+		compatible	= "Samsung,K3QF2F20DB","jedec,lpddr3";
+		density		= <16384>;
+		io-width	= <32>;
+
+		tRFC-min-tck		= <17>;
+		tRRD-min-tck		= <2>;
+		tRPab-min-tck		= <2>;
+		tRPpb-min-tck		= <2>;
+		tRCD-min-tck		= <3>;
+		tRC-min-tck		= <6>;
+		tRAS-min-tck		= <5>;
+		tWTR-min-tck		= <2>;
+		tWR-min-tck		= <7>;
+		tRTP-min-tck		= <2>;
+		tW2W-C2C-min-tck	= <0>;
+		tR2R-C2C-min-tck	= <0>;
+		tWL-min-tck		= <8>;
+		tDQSCK-min-tck		= <5>;
+		tRL-min-tck		= <14>;
+		tFAW-min-tck		= <5>;
+		tXSR-min-tck		= <12>;
+		tXP-min-tck		= <2>;
+		tCKE-min-tck		= <2>;
+		tCKESR-min-tck		= <2>;
+		tMRD-min-tck		= <5>;
+
+		timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@0 {
+			compatible	= "jedec,lpddr3-timings";
+			min-freq	= <100000000>;
+			max-freq	= <800000000>;
+			tRFC		= <65000>;
+			tRRD		= <6000>;
+			tRPab		= <12000>;
+			tRPpb		= <12000>;
+			tRCD		= <10000>;
+			tRC		= <33750>;
+			tRAS		= <23000>;
+			tWTR		= <3750>;
+			tWR		= <7500>;
+			tRTP		= <3750>;
+			tW2W-C2C	= <0>;
+			tR2R-C2C	= <0>;
+			tFAW		= <25000>;
+			tXSR		= <70000>;
+			tXP		= <3750>;
+			tCKE		= <3750>;
+			tCKESR		= <3750>;
+			tMRD		= <7000>;
+		};
+	};
 };
 
 &adc {
@@ -132,6 +221,21 @@
 	cpu-supply = <&buck2_reg>;
 };
 
+&dmc {
+	devfreq-events = <&ppmu_event0_dmc0_0>, <&ppmu_event1_dmc0_0>,
+			<&ppmu_event3_dmc0_0>,
+			<&ppmu_event0_dmc0_1>,<&ppmu_event1_dmc0_1>,
+			<&ppmu_event3_dmc0_1>,
+			<&ppmu_event0_dmc1_0>, <&ppmu_event1_dmc1_0>,
+			<&ppmu_event3_dmc1_0>,
+			<&ppmu_event0_dmc1_1>,<&ppmu_event1_dmc1_1>,
+			<&ppmu_event3_dmc1_1>;
+	device-handle = <&samsung_K3QF2F20DB>;
+	operating-points-v2 = <&dmc_opp_table>;
+	vdd-supply = <&buck1_reg>;
+	status = "okay";
+};
+
 &hsi2c_4 {
 	status = "okay";
 
@@ -540,6 +644,22 @@
 	};
 };
 
+&ppmu_dmc0_0 {
+	status = "okay";
+};
+
+&ppmu_dmc0_1 {
+	status = "okay";
+};
+
+&ppmu_dmc1_0 {
+	status = "okay";
+};
+
+&ppmu_dmc1_1 {
+	status = "okay";
+};
+
 &tmu_cpu0 {
 	vtmu-supply = <&ldo7_reg>;
 };
-- 
2.7.4

Re: [PATCH v6 09/10] ARM: dts: exynos: add DMC device for exynos5422

[Krzysztof Kozlowski]

On Fri, 19 Apr 2019 at 16:19, Lukasz Luba <l.luba@partner.samsung.com> wrote:
>
> Add description of Dynamic Memory Controller and PPMU counters.
> They are used by exynos5422-dmc driver.
> There is a definition of the memory chip, hwich is then used during

which

> calculation of timings for each OPP.
> The algorithm in the driver needs these two sets to bound the timings.
>
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  arch/arm/boot/dts/exynos5420.dtsi             | 120 ++++++++++++++++++++++++++
>  arch/arm/boot/dts/exynos5422-odroid-core.dtsi | 120 ++++++++++++++++++++++++++
>  2 files changed, 240 insertions(+)
>
> diff --git a/arch/arm/boot/dts/exynos5420.dtsi b/arch/arm/boot/dts/exynos5420.dtsi
> index aaff158..b687cd7 100644
> --- a/arch/arm/boot/dts/exynos5420.dtsi
> +++ b/arch/arm/boot/dts/exynos5420.dtsi
> @@ -14,6 +14,7 @@
>  #include <dt-bindings/clock/exynos5420.h>
>  #include <dt-bindings/clock/exynos-audss-clk.h>
>  #include <dt-bindings/interrupt-controller/arm-gic.h>
> +#include <dt-bindings/pmu/exynos_ppmu.h>
>
>  / {
>         compatible = "samsung,exynos5420", "samsung,exynos5";
> @@ -235,6 +236,37 @@
>                         status = "disabled";
>                 };
>
> +               dmc: memory-controller@10c20000 {
> +                       compatible = "samsung,exynos5422-dmc";
> +                       reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,

I think in the driver you access range up to 0xff of each DREX memory
region. Do not map entire 0x10000 if not needed.


> +                               <0x10000000 0x1000>, <0x10030000 0x1000>;
> +                       clocks = <&clock CLK_FOUT_SPLL>,
> +                                <&clock CLK_MOUT_SCLK_SPLL>,
> +                                <&clock CLK_FF_DOUT_SPLL2>,
> +                                <&clock CLK_FOUT_BPLL>,
> +                                <&clock CLK_MOUT_BPLL>,
> +                                <&clock CLK_SCLK_BPLL>,
> +                                <&clock CLK_MOUT_MX_MSPLL_CCORE>,
> +                                <&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
> +                                <&clock CLK_MOUT_MCLK_CDREX>,
> +                                <&clock CLK_DOUT_CLK2X_PHY0>,
> +                                <&clock CLK_CLKM_PHY0>,
> +                                <&clock CLK_CLKM_PHY1>;
> +                       clock-names = "fout_spll",
> +                                     "mout_sclk_spll",
> +                                     "ff_dout_spll2",
> +                                     "fout_bpll",
> +                                     "mout_bpll",
> +                                     "sclk_bpll",
> +                                     "mout_mx_mspll_ccore",
> +                                     "mout_mx_mspll_ccore_phy",
> +                                     "mout_mclk_cdrex",
> +                                     "dout_clk2x_phy0",
> +                                     "clkm_phy0",
> +                                     "clkm_phy1";
> +                       status = "disabled";
> +               };
> +
>                 nocp_mem0_0: nocp@10ca1000 {
>                         compatible = "samsung,exynos5420-nocp";
>                         reg = <0x10CA1000 0x200>;
> @@ -271,6 +303,94 @@
>                         status = "disabled";
>                 };
>
> +               ppmu_dmc0_0: ppmu@10d00000 {
> +                       compatible = "samsung,exynos-ppmu";
> +                       reg = <0x10d00000 0x2000>;
> +                       clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
> +                       clock-names = "ppmu";
> +                       events {
> +                               ppmu_event0_dmc0_0: ppmu-event0-dmc0_0 {
> +                                       event-name = "ppmu-event0-dmc0_0";
> +                                       event-data-type = <PPMU_RO_DATA_CNT>;
> +                               };
> +                               ppmu_event1_dmc0_0: ppmu-event1-dmc0_0 {
> +                                       event-name = "ppmu-event1-dmc0_0";
> +                                       event-data-type = <PPMU_WO_DATA_CNT>;
> +                               };
> +                               ppmu_event3_dmc0_0: ppmu-event3-dmc0_0 {
> +                                       event-name = "ppmu-event3-dmc0_0";
> +                                       event-data-type = <(PPMU_RO_DATA_CNT |
> +                                               PPMU_WO_DATA_CNT)>;
> +                               };
> +                       };
> +               };
> +
> +               ppmu_dmc0_1: ppmu@10d10000 {
> +                       compatible = "samsung,exynos-ppmu";
> +                       reg = <0x10d10000 0x2000>;
> +                       clocks = <&clock CLK_PCLK_PPMU_DREX0_1>;
> +                       clock-names = "ppmu";
> +                       events {
> +                               ppmu_event0_dmc0_1: ppmu-event0-dmc0_1 {
> +                                       event-name = "ppmu-event0-dmc0_1";
> +                                       event-data-type = <PPMU_RO_DATA_CNT>;
> +                               };
> +                               ppmu_event1_dmc0_1: ppmu-event1-dmc0_1 {
> +                                       event-name = "ppmu-event1-dmc0_1";
> +                                       event-data-type = <PPMU_WO_DATA_CNT>;
> +                               };
> +                               ppmu_event3_dmc0_1: ppmu-event3-dmc0_1 {
> +                                       event-name = "ppmu-event3-dmc0_1";
> +                                       event-data-type = <(PPMU_RO_DATA_CNT |
> +                                               PPMU_WO_DATA_CNT)>;
> +                               };
> +                       };
> +               };
> +
> +               ppmu_dmc1_0: ppmu@10d60000 {
> +                       compatible = "samsung,exynos-ppmu";
> +                       reg = <0x10d60000 0x2000>;
> +                       clocks = <&clock CLK_PCLK_PPMU_DREX1_0>;
> +                       clock-names = "ppmu";
> +                       events {
> +                               ppmu_event0_dmc1_0: ppmu-event0-dmc1_0 {
> +                                       event-name = "ppmu-event0-dmc1_0";
> +                                       event-data-type = <PPMU_RO_DATA_CNT>;
> +                               };
> +                               ppmu_event1_dmc1_0: ppmu-event1-dmc1_0 {
> +                                       event-name = "ppmu-event1-dmc1_0";
> +                                       event-data-type = <PPMU_WO_DATA_CNT>;
> +                               };
> +                               ppmu_event3_dmc1_0: ppmu-event3-dmc1_0 {
> +                                       event-name = "ppmu-event3-dmc1_0";
> +                                       event-data-type = <(PPMU_RO_DATA_CNT |
> +                                               PPMU_WO_DATA_CNT)>;
> +                               };
> +                       };
> +               };
> +
> +               ppmu_dmc1_1: ppmu@10d70000 {
> +                       compatible = "samsung,exynos-ppmu";
> +                       reg = <0x10d70000 0x2000>;
> +                       clocks = <&clock CLK_PCLK_PPMU_DREX1_1>;
> +                       clock-names = "ppmu";
> +                       events {
> +                               ppmu_event0_dmc1_1: ppmu-event0-dmc1_1 {
> +                                       event-name = "ppmu-event0-dmc1_1";
> +                                       event-data-type = <PPMU_RO_DATA_CNT>;
> +                               };
> +                               ppmu_event1_dmc1_1: ppmu-event1-dmc1_1 {
> +                                       event-name = "ppmu-event1-dmc1_1";
> +                                       event-data-type = <PPMU_WO_DATA_CNT>;
> +                               };
> +                               ppmu_event3_dmc1_1: ppmu-event3-dmc1_1 {
> +                                       event-name = "ppmu-event3-dmc1_1";
> +                                       event-data-type = <(PPMU_RO_DATA_CNT |
> +                                               PPMU_WO_DATA_CNT)>;
> +                               };
> +                       };
> +               };
> +
>                 gsc_pd: power-domain@10044000 {
>                         compatible = "samsung,exynos4210-pd";
>                         reg = <0x10044000 0x20>;
> diff --git a/arch/arm/boot/dts/exynos5422-odroid-core.dtsi b/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
> index 25d95de1..76bf0dbf 100644
> --- a/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
> +++ b/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
> @@ -34,6 +34,95 @@
>                         clock-frequency = <24000000>;
>                 };
>         };
> +
> +       dmc_opp_table: opp_table2 {
> +               compatible = "operating-points-v2";
> +
> +               opp00 {
> +                       opp-hz = /bits/ 64 <165000000>;
> +                       opp-microvolt = <875000>;
> +               };
> +               opp01 {
> +                       opp-hz = /bits/ 64 <206000000>;
> +                       opp-microvolt = <875000>;
> +               };
> +               opp02 {
> +                       opp-hz = /bits/ 64 <275000000>;
> +                       opp-microvolt = <875000>;
> +               };
> +               opp03 {
> +                       opp-hz = /bits/ 64 <413000000>;
> +                       opp-microvolt = <887500>;
> +               };
> +               opp04 {
> +                       opp-hz = /bits/ 64 <543000000>;
> +                       opp-microvolt = <937500>;
> +               };
> +               opp05 {
> +                       opp-hz = /bits/ 64 <633000000>;
> +                       opp-microvolt = <1012500>;
> +               };
> +               opp06 {
> +                       opp-hz = /bits/ 64 <728000000>;
> +                       opp-microvolt = <1037500>;
> +               };
> +               opp07 {
> +                       opp-hz = /bits/ 64 <825000000>;
> +                       opp-microvolt = <1050000>;
> +               };
> +       };
> +
> +       samsung_K3QF2F20DB: lpddr3 {
> +               compatible      = "Samsung,K3QF2F20DB","jedec,lpddr3";

Missing space after coma.

> +               density         = <16384>;
> +               io-width        = <32>;
> +
> +               tRFC-min-tck            = <17>;
> +               tRRD-min-tck            = <2>;
> +               tRPab-min-tck           = <2>;
> +               tRPpb-min-tck           = <2>;
> +               tRCD-min-tck            = <3>;
> +               tRC-min-tck             = <6>;
> +               tRAS-min-tck            = <5>;
> +               tWTR-min-tck            = <2>;
> +               tWR-min-tck             = <7>;
> +               tRTP-min-tck            = <2>;
> +               tW2W-C2C-min-tck        = <0>;
> +               tR2R-C2C-min-tck        = <0>;
> +               tWL-min-tck             = <8>;
> +               tDQSCK-min-tck          = <5>;
> +               tRL-min-tck             = <14>;
> +               tFAW-min-tck            = <5>;
> +               tXSR-min-tck            = <12>;
> +               tXP-min-tck             = <2>;
> +               tCKE-min-tck            = <2>;
> +               tCKESR-min-tck          = <2>;
> +               tMRD-min-tck            = <5>;
> +
> +               timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@0 {

@0 does not look correct... you do not have <reg>. No DTC warnings here?

Best regards,
Krzysztof

Re: [PATCH v6 09/10] ARM: dts: exynos: add DMC device for exynos5422

[Lukasz Luba]

Hi Krzysztof,

Thank you the review, please check my comments below.

On 4/23/19 1:03 PM, Krzysztof Kozlowski wrote:
> On Fri, 19 Apr 2019 at 16:19, Lukasz Luba <l.luba@partner.samsung.com> wrote:
>>
>> Add description of Dynamic Memory Controller and PPMU counters.
>> They are used by exynos5422-dmc driver.
>> There is a definition of the memory chip, hwich is then used during
> 
> which
ACK
> 
>> calculation of timings for each OPP.
>> The algorithm in the driver needs these two sets to bound the timings.
>>
>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>> ---
>>   arch/arm/boot/dts/exynos5420.dtsi             | 120 ++++++++++++++++++++++++++
>>   arch/arm/boot/dts/exynos5422-odroid-core.dtsi | 120 ++++++++++++++++++++++++++
>>   2 files changed, 240 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/exynos5420.dtsi b/arch/arm/boot/dts/exynos5420.dtsi
>> index aaff158..b687cd7 100644
>> --- a/arch/arm/boot/dts/exynos5420.dtsi
>> +++ b/arch/arm/boot/dts/exynos5420.dtsi
>> @@ -14,6 +14,7 @@
>>   #include <dt-bindings/clock/exynos5420.h>
>>   #include <dt-bindings/clock/exynos-audss-clk.h>
>>   #include <dt-bindings/interrupt-controller/arm-gic.h>
>> +#include <dt-bindings/pmu/exynos_ppmu.h>
>>
>>   / {
>>          compatible = "samsung,exynos5420", "samsung,exynos5";
>> @@ -235,6 +236,37 @@
>>                          status = "disabled";
>>                  };
>>
>> +               dmc: memory-controller@10c20000 {
>> +                       compatible = "samsung,exynos5422-dmc";
>> +                       reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
> 
> I think in the driver you access range up to 0xff of each DREX memory
> region. Do not map entire 0x10000 if not needed.
I agree, I will map only 0x100.
> 
> 
>> +                               <0x10000000 0x1000>, <0x10030000 0x1000>;
>> +                       clocks = <&clock CLK_FOUT_SPLL>,
>> +                                <&clock CLK_MOUT_SCLK_SPLL>,
>> +                                <&clock CLK_FF_DOUT_SPLL2>,
>> +                                <&clock CLK_FOUT_BPLL>,
>> +                                <&clock CLK_MOUT_BPLL>,
>> +                                <&clock CLK_SCLK_BPLL>,
>> +                                <&clock CLK_MOUT_MX_MSPLL_CCORE>,
>> +                                <&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
>> +                                <&clock CLK_MOUT_MCLK_CDREX>,
>> +                                <&clock CLK_DOUT_CLK2X_PHY0>,
>> +                                <&clock CLK_CLKM_PHY0>,
>> +                                <&clock CLK_CLKM_PHY1>;
>> +                       clock-names = "fout_spll",
>> +                                     "mout_sclk_spll",
>> +                                     "ff_dout_spll2",
>> +                                     "fout_bpll",
>> +                                     "mout_bpll",
>> +                                     "sclk_bpll",
>> +                                     "mout_mx_mspll_ccore",
>> +                                     "mout_mx_mspll_ccore_phy",
>> +                                     "mout_mclk_cdrex",
>> +                                     "dout_clk2x_phy0",
>> +                                     "clkm_phy0",
>> +                                     "clkm_phy1";
>> +                       status = "disabled";
>> +               };
>> +
>>                  nocp_mem0_0: nocp@10ca1000 {
>>                          compatible = "samsung,exynos5420-nocp";
>>                          reg = <0x10CA1000 0x200>;
>> @@ -271,6 +303,94 @@
>>                          status = "disabled";
>>                  };
>>
>> +               ppmu_dmc0_0: ppmu@10d00000 {
>> +                       compatible = "samsung,exynos-ppmu";
>> +                       reg = <0x10d00000 0x2000>;
>> +                       clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
>> +                       clock-names = "ppmu";
>> +                       events {
>> +                               ppmu_event0_dmc0_0: ppmu-event0-dmc0_0 {
>> +                                       event-name = "ppmu-event0-dmc0_0";
>> +                                       event-data-type = <PPMU_RO_DATA_CNT>;
>> +                               };
>> +                               ppmu_event1_dmc0_0: ppmu-event1-dmc0_0 {
>> +                                       event-name = "ppmu-event1-dmc0_0";
>> +                                       event-data-type = <PPMU_WO_DATA_CNT>;
>> +                               };
>> +                               ppmu_event3_dmc0_0: ppmu-event3-dmc0_0 {
>> +                                       event-name = "ppmu-event3-dmc0_0";
>> +                                       event-data-type = <(PPMU_RO_DATA_CNT |
>> +                                               PPMU_WO_DATA_CNT)>;
>> +                               };
>> +                       };
>> +               };
>> +
>> +               ppmu_dmc0_1: ppmu@10d10000 {
>> +                       compatible = "samsung,exynos-ppmu";
>> +                       reg = <0x10d10000 0x2000>;
>> +                       clocks = <&clock CLK_PCLK_PPMU_DREX0_1>;
>> +                       clock-names = "ppmu";
>> +                       events {
>> +                               ppmu_event0_dmc0_1: ppmu-event0-dmc0_1 {
>> +                                       event-name = "ppmu-event0-dmc0_1";
>> +                                       event-data-type = <PPMU_RO_DATA_CNT>;
>> +                               };
>> +                               ppmu_event1_dmc0_1: ppmu-event1-dmc0_1 {
>> +                                       event-name = "ppmu-event1-dmc0_1";
>> +                                       event-data-type = <PPMU_WO_DATA_CNT>;
>> +                               };
>> +                               ppmu_event3_dmc0_1: ppmu-event3-dmc0_1 {
>> +                                       event-name = "ppmu-event3-dmc0_1";
>> +                                       event-data-type = <(PPMU_RO_DATA_CNT |
>> +                                               PPMU_WO_DATA_CNT)>;
>> +                               };
>> +                       };
>> +               };
>> +
>> +               ppmu_dmc1_0: ppmu@10d60000 {
>> +                       compatible = "samsung,exynos-ppmu";
>> +                       reg = <0x10d60000 0x2000>;
>> +                       clocks = <&clock CLK_PCLK_PPMU_DREX1_0>;
>> +                       clock-names = "ppmu";
>> +                       events {
>> +                               ppmu_event0_dmc1_0: ppmu-event0-dmc1_0 {
>> +                                       event-name = "ppmu-event0-dmc1_0";
>> +                                       event-data-type = <PPMU_RO_DATA_CNT>;
>> +                               };
>> +                               ppmu_event1_dmc1_0: ppmu-event1-dmc1_0 {
>> +                                       event-name = "ppmu-event1-dmc1_0";
>> +                                       event-data-type = <PPMU_WO_DATA_CNT>;
>> +                               };
>> +                               ppmu_event3_dmc1_0: ppmu-event3-dmc1_0 {
>> +                                       event-name = "ppmu-event3-dmc1_0";
>> +                                       event-data-type = <(PPMU_RO_DATA_CNT |
>> +                                               PPMU_WO_DATA_CNT)>;
>> +                               };
>> +                       };
>> +               };
>> +
>> +               ppmu_dmc1_1: ppmu@10d70000 {
>> +                       compatible = "samsung,exynos-ppmu";
>> +                       reg = <0x10d70000 0x2000>;
>> +                       clocks = <&clock CLK_PCLK_PPMU_DREX1_1>;
>> +                       clock-names = "ppmu";
>> +                       events {
>> +                               ppmu_event0_dmc1_1: ppmu-event0-dmc1_1 {
>> +                                       event-name = "ppmu-event0-dmc1_1";
>> +                                       event-data-type = <PPMU_RO_DATA_CNT>;
>> +                               };
>> +                               ppmu_event1_dmc1_1: ppmu-event1-dmc1_1 {
>> +                                       event-name = "ppmu-event1-dmc1_1";
>> +                                       event-data-type = <PPMU_WO_DATA_CNT>;
>> +                               };
>> +                               ppmu_event3_dmc1_1: ppmu-event3-dmc1_1 {
>> +                                       event-name = "ppmu-event3-dmc1_1";
>> +                                       event-data-type = <(PPMU_RO_DATA_CNT |
>> +                                               PPMU_WO_DATA_CNT)>;
>> +                               };
>> +                       };
>> +               };
>> +
>>                  gsc_pd: power-domain@10044000 {
>>                          compatible = "samsung,exynos4210-pd";
>>                          reg = <0x10044000 0x20>;
>> diff --git a/arch/arm/boot/dts/exynos5422-odroid-core.dtsi b/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
>> index 25d95de1..76bf0dbf 100644
>> --- a/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
>> +++ b/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
>> @@ -34,6 +34,95 @@
>>                          clock-frequency = <24000000>;
>>                  };
>>          };
>> +
>> +       dmc_opp_table: opp_table2 {
>> +               compatible = "operating-points-v2";
>> +
>> +               opp00 {
>> +                       opp-hz = /bits/ 64 <165000000>;
>> +                       opp-microvolt = <875000>;
>> +               };
>> +               opp01 {
>> +                       opp-hz = /bits/ 64 <206000000>;
>> +                       opp-microvolt = <875000>;
>> +               };
>> +               opp02 {
>> +                       opp-hz = /bits/ 64 <275000000>;
>> +                       opp-microvolt = <875000>;
>> +               };
>> +               opp03 {
>> +                       opp-hz = /bits/ 64 <413000000>;
>> +                       opp-microvolt = <887500>;
>> +               };
>> +               opp04 {
>> +                       opp-hz = /bits/ 64 <543000000>;
>> +                       opp-microvolt = <937500>;
>> +               };
>> +               opp05 {
>> +                       opp-hz = /bits/ 64 <633000000>;
>> +                       opp-microvolt = <1012500>;
>> +               };
>> +               opp06 {
>> +                       opp-hz = /bits/ 64 <728000000>;
>> +                       opp-microvolt = <1037500>;
>> +               };
>> +               opp07 {
>> +                       opp-hz = /bits/ 64 <825000000>;
>> +                       opp-microvolt = <1050000>;
>> +               };
>> +       };
>> +
>> +       samsung_K3QF2F20DB: lpddr3 {
>> +               compatible      = "Samsung,K3QF2F20DB","jedec,lpddr3";
> 
> Missing space after coma.
Good catch, thank you.
> 
>> +               density         = <16384>;
>> +               io-width        = <32>;
>> +
>> +               tRFC-min-tck            = <17>;
>> +               tRRD-min-tck            = <2>;
>> +               tRPab-min-tck           = <2>;
>> +               tRPpb-min-tck           = <2>;
>> +               tRCD-min-tck            = <3>;
>> +               tRC-min-tck             = <6>;
>> +               tRAS-min-tck            = <5>;
>> +               tWTR-min-tck            = <2>;
>> +               tWR-min-tck             = <7>;
>> +               tRTP-min-tck            = <2>;
>> +               tW2W-C2C-min-tck        = <0>;
>> +               tR2R-C2C-min-tck        = <0>;
>> +               tWL-min-tck             = <8>;
>> +               tDQSCK-min-tck          = <5>;
>> +               tRL-min-tck             = <14>;
>> +               tFAW-min-tck            = <5>;
>> +               tXSR-min-tck            = <12>;
>> +               tXP-min-tck             = <2>;
>> +               tCKE-min-tck            = <2>;
>> +               tCKESR-min-tck          = <2>;
>> +               tMRD-min-tck            = <5>;
>> +
>> +               timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@0 {
> 
> @0 does not look correct... you do not have <reg>. No DTC warnings here?
Rob also pointed out that it should have 'reg'. I have followed the
LPDDR2 definitions, but in the meantime DT rules have changed and now
'reg' is needed. I will put 'reg' instead of 'max-freq' if Rob agrees.

Regards,
Lukasz
> 
> Best regards,
> Krzysztof
> 
> 

[PATCH v6 10/10] ARM: exynos_defconfig: enable DMC driver

[Lukasz Luba]

Enable driver for Exynos5422 Dynamic Memory Controller supporting
dynamic frequency and voltage scaling in Exynos5422 SoCs.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 arch/arm/configs/exynos_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig
index d635edf..04c076e 100644
--- a/arch/arm/configs/exynos_defconfig
+++ b/arch/arm/configs/exynos_defconfig
@@ -291,6 +291,7 @@ CONFIG_DEVFREQ_GOV_PERFORMANCE=y
 CONFIG_DEVFREQ_GOV_POWERSAVE=y
 CONFIG_DEVFREQ_GOV_USERSPACE=y
 CONFIG_ARM_EXYNOS_BUS_DEVFREQ=y
+CONFIG_ARM_EXYNOS5422_DMC=y
 CONFIG_DEVFREQ_EVENT_EXYNOS_NOCP=y
 CONFIG_EXYNOS_IOMMU=y
 CONFIG_EXTCON=y
-- 
2.7.4