[PATCH v2 0/6] ARM: berlin: add cpufreq support

[PATCH v2 0/6] ARM: berlin: add cpufreq support

[Antoine Tenart]

Hi,

This series adds the cpufreq support to the Berlin SoCs, using
cpufreq-dt.

First, the cpuclk clock is added to the BG2Q clock driver. This clock
has a divider fixed to 1, so we use a fixed factor clock here.

Then register a platform device for cpufreq-dt.

I also added the OPP table definition in the BG2Q, BG2 and BG2CD device
trees. When using a BG2Q, some bootloaders may update this table when
booting (mine doesn't).

Tested on a BG2Q DMP.

Thanks,

Antoine

Changes since v1:
	- added the BG2 and BG2CD support
	- moved MAX_CLKS out of the Berlin clk driver
	- reordered the patches

Antoine Tenart (6):
  clk: berlin: move MAX_CLKS out of drivers/clk/berlin
  clk: berlin: add cpuclk
  ARM: berlin: dts: add the cpufreq-dt bindings on the BG2Q
  ARM: berlin: dts: add the cpufreq-dt bindings on the BG2
  ARM: berlin: dts: add the cpufreq-dt bindings on the BG2CD
  ARM: berlin: register cpufreq-dt

 arch/arm/boot/dts/berlin2.dtsi       | 10 ++++++++++
 arch/arm/boot/dts/berlin2cd.dtsi     |  8 ++++++++
 arch/arm/boot/dts/berlin2q.dtsi      | 11 +++++++++++
 arch/arm/mach-berlin/berlin.c        |  6 ++++++
 drivers/clk/berlin/bg2.c             |  1 -
 drivers/clk/berlin/bg2q.c            | 13 ++++++-------
 include/dt-bindings/clock/berlin2.h  |  2 ++
 include/dt-bindings/clock/berlin2q.h |  3 +++
 8 files changed, 46 insertions(+), 8 deletions(-)

-- 
2.5.0

[PATCH v2 3/6] ARM: berlin: dts: add the cpufreq-dt bindings on the BG2Q

[Antoine Tenart]

The BG2Q uses cpugreq-dt. Add the corresponding bindings. The operating
points can be updated by the bootloader.

Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
---
 arch/arm/boot/dts/berlin2q.dtsi | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/arm/boot/dts/berlin2q.dtsi b/arch/arm/boot/dts/berlin2q.dtsi
index 63a48490e2f9..58f6792c0d77 100644
--- a/arch/arm/boot/dts/berlin2q.dtsi
+++ b/arch/arm/boot/dts/berlin2q.dtsi
@@ -53,6 +53,17 @@
 			device_type = "cpu";
 			next-level-cache = <&l2>;
 			reg = <0>;
+
+			clocks = <&chip_clk CLKID_CPU>;
+			clock-latency = <100000>;
+			/* Can be modified by the bootloader */
+			operating-points = <
+				/* kHz    uV */
+				1200000 1200000
+				1000000 1200000
+				800000  1200000
+				600000  1200000
+			>;
 		};
 
 		cpu@1 {
-- 
2.5.0

[PATCH v2 4/6] ARM: berlin: dts: add the cpufreq-dt bindings on the BG2

[Antoine Tenart]

The BG2 uses cpugreq-dt. Add the corresponding bindings.

Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
---
 arch/arm/boot/dts/berlin2.dtsi | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/arm/boot/dts/berlin2.dtsi b/arch/arm/boot/dts/berlin2.dtsi
index ef811de09908..d80dc82729b8 100644
--- a/arch/arm/boot/dts/berlin2.dtsi
+++ b/arch/arm/boot/dts/berlin2.dtsi
@@ -57,6 +57,16 @@
 			device_type = "cpu";
 			next-level-cache = <&l2>;
 			reg = <0>;
+
+			clocks = <&chip_clk CLKID_CPU>;
+			clock-latency = <100000>;
+			operating-points = <
+				/* kHz    uV */
+				1200000 1200000
+				1000000 1200000
+				800000  1200000
+				600000  1200000
+			>;
 		};
 
 		cpu@1 {
-- 
2.5.0

[PATCH v2 5/6] ARM: berlin: dts: add the cpufreq-dt bindings on the BG2CD

[Antoine Tenart]

The BG2CD uses cpugreq-dt. Add the corresponding bindings.

Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
---
 arch/arm/boot/dts/berlin2cd.dtsi | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/arm/boot/dts/berlin2cd.dtsi b/arch/arm/boot/dts/berlin2cd.dtsi
index 900213d78a32..3c7a7404f10c 100644
--- a/arch/arm/boot/dts/berlin2cd.dtsi
+++ b/arch/arm/boot/dts/berlin2cd.dtsi
@@ -56,6 +56,14 @@
 			device_type = "cpu";
 			next-level-cache = <&l2>;
 			reg = <0>;
+
+			clocks = <&chip_clk CLKID_CPU>;
+			clock-latency = <100000>;
+			operating-points = <
+				/* kHz    uV */
+				800000  1200000
+				600000  1200000
+			>;
 		};
 	};
 
-- 
2.5.0

[PATCH v2 6/6] ARM: berlin: register cpufreq-dt

[Antoine Tenart]

The Berlin SoCs use cpufreq-dt for cpufreq. Register a platform device.

Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
---
 arch/arm/mach-berlin/berlin.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm/mach-berlin/berlin.c b/arch/arm/mach-berlin/berlin.c
index ac181c6797ee..25d73870ccca 100644
--- a/arch/arm/mach-berlin/berlin.c
+++ b/arch/arm/mach-berlin/berlin.c
@@ -18,6 +18,11 @@
 #include <asm/hardware/cache-l2x0.h>
 #include <asm/mach/arch.h>
 
+static void __init berlin_init_late(void)
+{
+	platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
+}
+
 static const char * const berlin_dt_compat[] = {
 	"marvell,berlin",
 	NULL,
@@ -25,6 +30,7 @@ static const char * const berlin_dt_compat[] = {
 
 DT_MACHINE_START(BERLIN_DT, "Marvell Berlin")
 	.dt_compat	= berlin_dt_compat,
+	.init_late	= berlin_init_late,
 	/*
 	 * with DT probing for L2CCs, berlin_init_machine can be removed.
 	 * Note: 88DE3005 (Armada 1500-mini) uses pl310 l2cc
-- 
2.5.0

Re: [PATCH v2 0/6] ARM: berlin: add cpufreq support

[Viresh Kumar]

On Tue, Aug 18, 2015 at 5:16 PM, Antoine Tenart
<antoine.tenart@free-electrons.com> wrote:
> Hi,
>
> This series adds the cpufreq support to the Berlin SoCs, using
> cpufreq-dt.
>
> First, the cpuclk clock is added to the BG2Q clock driver. This clock
> has a divider fixed to 1, so we use a fixed factor clock here.
>
> Then register a platform device for cpufreq-dt.
>
> I also added the OPP table definition in the BG2Q, BG2 and BG2CD device
> trees. When using a BG2Q, some bootloaders may update this table when
> booting (mine doesn't).

You can switch to OPP-v2 bindings if you want. Just have a look, they are
much more powerful.. Should be in linux-next/master.

Re: [PATCH v2 0/6] ARM: berlin: add cpufreq support

[Antoine Tenart]

Hi,

On Tue, Aug 18, 2015 at 06:26:42PM +0530, Viresh Kumar wrote:
> On Tue, Aug 18, 2015 at 5:16 PM, Antoine Tenart
> <antoine.tenart@free-electrons.com> wrote:
> >
> > This series adds the cpufreq support to the Berlin SoCs, using
> > cpufreq-dt.
> >
> > First, the cpuclk clock is added to the BG2Q clock driver. This clock
> > has a divider fixed to 1, so we use a fixed factor clock here.
> >
> > Then register a platform device for cpufreq-dt.
> >
> > I also added the OPP table definition in the BG2Q, BG2 and BG2CD device
> > trees. When using a BG2Q, some bootloaders may update this table when
> > booting (mine doesn't).
> 
> You can switch to OPP-v2 bindings if you want. Just have a look, they are
> much more powerful.. Should be in linux-next/master.

Nice!

However, it seems the OPP-v2 table takes precedence over the old one.
When a default OPP-v2 table is supplied in the device tree, if the
bootloader supplies an OPP table the old way it won't be taken into
account.

So if I understood correctly, this won't work here for the BG2Q.

Antoine

-- 
Antoine Ténart, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

Re: [PATCH v2 0/6] ARM: berlin: add cpufreq support

[Viresh Kumar]

On 18-08-15, 16:39, Antoine Tenart wrote:
> However, it seems the OPP-v2 table takes precedence over the old one.
> When a default OPP-v2 table is supplied in the device tree, if the
> bootloader supplies an OPP table the old way it won't be taken into
> account.
> 
> So if I understood correctly, this won't work here for the BG2Q.

Didn't understood it completely. Are you saying that your dtb will
have two operating-points tables ?

The deal is that for any device, parsing of opp-v2 will be attempted
first. If its not available, then opp-v1 will be tried. But this is
per-device. So, one device can have opp-v2 tables and other one can do
v1 type.

-- 
viresh

Re: [PATCH v2 0/6] ARM: berlin: add cpufreq support

[Antoine Tenart]

On Tue, Aug 18, 2015 at 08:29:25PM +0530, Viresh Kumar wrote:
> On 18-08-15, 16:39, Antoine Tenart wrote:
> > However, it seems the OPP-v2 table takes precedence over the old one.
> > When a default OPP-v2 table is supplied in the device tree, if the
> > bootloader supplies an OPP table the old way it won't be taken into
> > account.
> > 
> > So if I understood correctly, this won't work here for the BG2Q.
> 
> Didn't understood it completely. Are you saying that your dtb will
> have two operating-points tables ?

Yes. If the device tree has an OPP-v2 table and the bootloader modify it
to add an old OPP table at boot, the one added by the bootloader won't
be taken into account by the kernel.

> The deal is that for any device, parsing of opp-v2 will be attempted
> first. If its not available, then opp-v1 will be tried. But this is
> per-device. So, one device can have opp-v2 tables and other one can do
> v1 type.

Sure. OPP-v2 tables can be used for devices having an up-to-date
bootloader or if the bootloader do not modify the device tree at boot
time to add an (old) OPP table.

Antoine

-- 
Antoine Ténart, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com