[PATCH v6 0/4] Exynos SROMc configuration and Ethernet support for SMDK5410

[PATCH v6 0/4] Exynos SROMc configuration and Ethernet support for SMDK5410

[Pavel Fedin]

This patch extends Exynos SROM controller driver with ability to configure
controller outputs and enables SMSC9115 Ethernet chip on SMDK5410 board,
which is connected via SROMc bank #3.

With this patchset, support for the whole existing SMDK range can be added.
Actually, only bank number is different.

This patchset also depends on Exynos 5410 pinctrl support, introduced by
patches 0003 and 0004 from this set:
[PATCH v4 0/5] ARM: EXYNOS: ODROID-XU DT and LEDs
http://lists.infradead.org/pipermail/linux-arm-kernel/2015-March/330862.html

Pinctrl support is necessary in order to correctly configure
multifunctional pins of the Exynos chip.

v5 => v6:
- Even more improvements to the documentation, fixed some errors and typos.
- Separated adding bus ranges from generic SROMc support
- Some stuff renamed for even better code readability
- Stylistic cleanups in the DTS (everything in alphabetic order, use named
  constant name for interrupt config byte)

v4 => v5:
- Some cosmetic changes in the dtsi ("compatible" goes first)
- Use correctly specified ranges for the SROMc node
- Reuse existing properties where possible ("reg" for bank# and
  "reg-io-width" for data width)
- Separated page-mode property from timings array
- More improvements to the documentation

v3 => v4:
- Devices are now added as subnodes, with additional properties. This allows
  to cleary specify dependency. If configuration fails, error will be reported
  and child devices will not be probed.
- These additional properties now have "samsung,srom-XXX" format
- Fixed code style, now better understood.

v2 => v3:
- Fixed up SROMc region size in the device tree
- Reordered patches, documentation goes first now

v1 => v2:
- Fixed some typos and bad labels in device tree
- Improved documentation

Pavel Fedin (4):
  Documentation: dt-bindings: Describe SROMc configuration
  ARM: dts: Add SROMc to Exynos 5410
  drivers: exynos-srom: Add support for bank configuration
  ARM: dts: Add Ethernet chip to SMDK5410

 .../bindings/arm/samsung/exynos-srom.txt           | 71 +++++++++++++++++++++-
 arch/arm/boot/dts/exynos5410-smdk5410.dts          | 41 +++++++++++++
 arch/arm/boot/dts/exynos5410.dtsi                  | 11 ++++
 arch/arm/mach-exynos/Kconfig                       |  2 +-
 drivers/soc/samsung/Kconfig                        |  2 +-
 drivers/soc/samsung/exynos-srom.c                  | 61 ++++++++++++++++++-
 6 files changed, 182 insertions(+), 6 deletions(-)

-- 
2.4.4

[PATCH v6 1/4] Documentation: dt-bindings: Describe SROMc configuration

[Pavel Fedin]

Add documentation for new subnode properties, allowing bank configuration.
Based on u-boot implementation, but heavily reworked.

Also, fix size of SROMc mapping in the example.

Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
---
 .../bindings/arm/samsung/exynos-srom.txt           | 71 +++++++++++++++++++++-
 1 file changed, 69 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/arm/samsung/exynos-srom.txt b/Documentation/devicetree/bindings/arm/samsung/exynos-srom.txt
index 33886d5..cce5c1f 100644
--- a/Documentation/devicetree/bindings/arm/samsung/exynos-srom.txt
+++ b/Documentation/devicetree/bindings/arm/samsung/exynos-srom.txt
@@ -5,8 +5,75 @@ Required properties:
 
 - reg: offset and length of the register set
 
-Example:
+Optional properties:
+The SROM controller can be used to attach external peripherals. In this case
+extra properties, describing the bus behind it, should be specified as below:
+
+- #address-cells: Must be set to 2 to allow memory address translation
+
+- #size-cells: Must be set to 1 to allow CS address passing
+
+- ranges: Must be set up to reflect the memory layout with four integer values
+	  per bank:
+		<bank-number> 0 <physical address of bank> <size>
+
+Sub-nodes:
+The actual device nodes should be added as subnodes to the SROMc node. These
+subnodes, except regular device specification, should contain the following
+properties, describing configuration of the relevant SROM bank:
+
+Required properties:
+- reg: bank number, base address (relative to start of the bank) and size of
+       the memory mapped for the device. Note that base address will be
+       typically 0 as this is the start of the bank.
+
+- samsung,srom-timing : array of 6 integers, specifying bank timings in the
+                        following order: Tacp, Tcah, Tcoh, Tacc, Tcos, Tacs.
+                        Each value is specified in cycles and has the following
+                        meaning and valid range:
+                        Tacp : Page mode access cycle at Page mode (0 - 15)
+                        Tcah : Address holding time after CSn (0 - 15)
+                        Tcoh : Chip selection hold on OEn (0 - 15)
+                        Tacc : Access cycle (0 - 32)
+                        Tcos : Chip selection set-up before OEn (0 - 15)
+                        Tacs : Address set-up before CSn (0 - 15)
+
+Optional properties:
+- reg-io-width : data width in bytes (1 or 2). If omitted, default of 1 is used.
+
+- samsung,srom-page-mode : page mode configuration for the bank:
+			   0 - normal (one data)
+			   1 - four data
+			   If omitted, default of 0 is used.
+
+Example: basic definition, no banks are configured
+	sromc at 12570000 {
+		compatible = "samsung,exynos-srom";
+		reg = <0x12570000 0x14>;
+	};
+
+Example: SROMc with SMSC911x ethernet chip on bank 3
 	sromc at 12570000 {
+		#address-cells = <2>;
+		#size-cells = <1>;
+		ranges = <0 0 0x04000000 0x20000   // Bank0
+			  1 0 0x05000000 0x20000   // Bank1
+			  2 0 0x06000000 0x20000   // Bank2
+			  3 0 0x07000000 0x20000>; // Bank3
+
 		compatible = "samsung,exynos-srom";
-		reg = <0x12570000 0x10>;
+		reg = <0x12570000 0x14>;
+
+		ethernet at 3 {
+			compatible = "smsc,lan9115";
+			reg = <3 0 0x10000>;	   // Bank 3, offset = 0
+			phy-mode = "mii";
+			interrupt-parent = <&gpx0>;
+			interrupts = <5 8>;
+			reg-io-width = <2>;
+			smsc,irq-push-pull;
+			smsc,force-internal-phy;
+
+			samsung,srom-config = <1 9 12 1 9 1 1>;
+		};
 	};
-- 
2.4.4

[PATCH v6 1/4] Documentation: dt-bindings: Describe SROMc configuration

[Krzysztof Kozlowski]

On 05.11.2015 21:03, Pavel Fedin wrote:
> Add documentation for new subnode properties, allowing bank configuration.
> Based on u-boot implementation, but heavily reworked.
> 
> Also, fix size of SROMc mapping in the example.
> 
> Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
> ---
>  .../bindings/arm/samsung/exynos-srom.txt           | 71 +++++++++++++++++++++-
>  1 file changed, 69 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/arm/samsung/exynos-srom.txt b/Documentation/devicetree/bindings/arm/samsung/exynos-srom.txt
> index 33886d5..cce5c1f 100644
> --- a/Documentation/devicetree/bindings/arm/samsung/exynos-srom.txt
> +++ b/Documentation/devicetree/bindings/arm/samsung/exynos-srom.txt
> @@ -5,8 +5,75 @@ Required properties:
>  
>  - reg: offset and length of the register set
>  
> -Example:
> +Optional properties:
> +The SROM controller can be used to attach external peripherals. In this case
> +extra properties, describing the bus behind it, should be specified as below:
> +
> +- #address-cells: Must be set to 2 to allow memory address translation
> +
> +- #size-cells: Must be set to 1 to allow CS address passing
> +
> +- ranges: Must be set up to reflect the memory layout with four integer values
> +	  per bank:
> +		<bank-number> 0 <physical address of bank> <size>
> +
> +Sub-nodes:
> +The actual device nodes should be added as subnodes to the SROMc node. These
> +subnodes, except regular device specification, should contain the following
> +properties, describing configuration of the relevant SROM bank:
> +
> +Required properties:
> +- reg: bank number, base address (relative to start of the bank) and size of
> +       the memory mapped for the device. Note that base address will be
> +       typically 0 as this is the start of the bank.
> +
> +- samsung,srom-timing : array of 6 integers, specifying bank timings in the
> +                        following order: Tacp, Tcah, Tcoh, Tacc, Tcos, Tacs.
> +                        Each value is specified in cycles and has the following
> +                        meaning and valid range:
> +                        Tacp : Page mode access cycle at Page mode (0 - 15)
> +                        Tcah : Address holding time after CSn (0 - 15)
> +                        Tcoh : Chip selection hold on OEn (0 - 15)
> +                        Tacc : Access cycle (0 - 32)

All of the manuals have error here. Probably it can be either: 1-32 or
0-31. I would bet on 0-31, what do you think?

Rest looks good:

Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

Best regards,
Krzysztof

[PATCH v6 1/4] Documentation: dt-bindings: Describe SROMc configuration

[Pavel Fedin]

 Hello!

> > +- samsung,srom-timing : array of 6 integers, specifying bank timings in the
> > +                        following order: Tacp, Tcah, Tcoh, Tacc, Tcos, Tacs.
> > +                        Each value is specified in cycles and has the following
> > +                        meaning and valid range:
> > +                        Tacp : Page mode access cycle at Page mode (0 - 15)
> > +                        Tcah : Address holding time after CSn (0 - 15)
> > +                        Tcoh : Chip selection hold on OEn (0 - 15)
> > +                        Tacc : Access cycle (0 - 32)
> 
> All of the manuals have error here. Probably it can be either: 1-32 or
> 0-31. I would bet on 0-31, what do you think?

 Damn, everything starts from 0, so i automatically put '0 - 32'. The actual time, however, varies from 1 to 32, but the value is
from 0 to 31, i. e. <time> - 1
 What shall we do? Just document this, or adjust the code to take number of cycles and subtract 1? To tell the truth, i'm already
sick of these small fixups, and i would prefer just to fix documentation.

Kind regards,
Pavel Fedin
Expert Engineer
Samsung Electronics Research center Russia

[PATCH v6 1/4] Documentation: dt-bindings: Describe SROMc configuration

[Krzysztof Kozlowski]

On 06.11.2015 17:14, Pavel Fedin wrote:
>  Hello!
> 
>>> +- samsung,srom-timing : array of 6 integers, specifying bank timings in the
>>> +                        following order: Tacp, Tcah, Tcoh, Tacc, Tcos, Tacs.
>>> +                        Each value is specified in cycles and has the following
>>> +                        meaning and valid range:
>>> +                        Tacp : Page mode access cycle at Page mode (0 - 15)
>>> +                        Tcah : Address holding time after CSn (0 - 15)
>>> +                        Tcoh : Chip selection hold on OEn (0 - 15)
>>> +                        Tacc : Access cycle (0 - 32)
>>
>> All of the manuals have error here. Probably it can be either: 1-32 or
>> 0-31. I would bet on 0-31, what do you think?
> 
>  Damn, everything starts from 0, so i automatically put '0 - 32'. The actual time, however, varies from 1 to 32, but the value is
> from 0 to 31, i. e. <time> - 1
>  What shall we do? Just document this, or adjust the code to take number of cycles and subtract 1? To tell the truth, i'm already
> sick of these small fixups, and i would prefer just to fix documentation.

Whatever you choose. Just make it correct. :) The problem is that
Datasheet has errors for these values...

Best regards,
Krzysztof

[PATCH v6 2/4] ARM: dts: Add SROMc to Exynos 5410

[Pavel Fedin]

This machine uses own SoC device tree file, add missing part.

Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
---
 arch/arm/boot/dts/exynos5410.dtsi | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/exynos5410.dtsi b/arch/arm/boot/dts/exynos5410.dtsi
index 4603356..e2b58f8 100644
--- a/arch/arm/boot/dts/exynos5410.dtsi
+++ b/arch/arm/boot/dts/exynos5410.dtsi
@@ -101,6 +101,11 @@
 			reg = <0x10000000 0x100>;
 		};
 
+		sromc: sromc at 12250000 {
+			compatible = "samsung,exynos-srom";
+			reg = <0x12250000 0x14>;
+		};
+
 		pmu_system_controller: system-controller at 10040000 {
 			compatible = "samsung,exynos5410-pmu", "syscon";
 			reg = <0x10040000 0x5000>;
-- 
2.4.4

[PATCH v6 2/4] ARM: dts: Add SROMc to Exynos 5410

[Krzysztof Kozlowski]

On 05.11.2015 21:03, Pavel Fedin wrote:
> This machine uses own SoC device tree file, add missing part.
> 
> Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
> ---
>  arch/arm/boot/dts/exynos5410.dtsi | 5 +++++
>  1 file changed, 5 insertions(+)

Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

Best regards,
Krzysztof

[PATCH v6 3/4] drivers: exynos-srom: Add support for bank configuration

[Pavel Fedin]

Implement handling properties in subnodes and adding child devices to the
system. Child devices will not be added if configuration fails.

Since the driver now does more than suspend-resume support, dependency on
CONFIG_PM is removed.

Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
---
 arch/arm/mach-exynos/Kconfig      |  2 +-
 drivers/soc/samsung/Kconfig       |  2 +-
 drivers/soc/samsung/exynos-srom.c | 61 +++++++++++++++++++++++++++++++++++++--
 3 files changed, 61 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-exynos/Kconfig b/arch/arm/mach-exynos/Kconfig
index 83c85f5..c22dc42 100644
--- a/arch/arm/mach-exynos/Kconfig
+++ b/arch/arm/mach-exynos/Kconfig
@@ -16,7 +16,7 @@ menuconfig ARCH_EXYNOS
 	select ARM_GIC
 	select COMMON_CLK_SAMSUNG
 	select EXYNOS_THERMAL
-	select EXYNOS_SROM if PM
+	select EXYNOS_SROM
 	select HAVE_ARM_SCU if SMP
 	select HAVE_S3C2410_I2C if I2C
 	select HAVE_S3C2410_WATCHDOG if WATCHDOG
diff --git a/drivers/soc/samsung/Kconfig b/drivers/soc/samsung/Kconfig
index 2833b5b..ea4bc2a 100644
--- a/drivers/soc/samsung/Kconfig
+++ b/drivers/soc/samsung/Kconfig
@@ -8,6 +8,6 @@ config SOC_SAMSUNG
 
 config EXYNOS_SROM
 	bool
-	depends on ARM && ARCH_EXYNOS && PM
+	depends on ARM && ARCH_EXYNOS
 
 endmenu
diff --git a/drivers/soc/samsung/exynos-srom.c b/drivers/soc/samsung/exynos-srom.c
index 57a232d..a4cf547 100644
--- a/drivers/soc/samsung/exynos-srom.c
+++ b/drivers/soc/samsung/exynos-srom.c
@@ -14,6 +14,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 
@@ -67,11 +68,51 @@ static struct exynos_srom_reg_dump *exynos_srom_alloc_reg_dump(
 	return rd;
 }
 
+static int exynos_srom_configure_bank(struct exynos_srom *srom,
+				      struct device_node *np)
+{
+	u32 bank, width, pmc;
+	u32 timing[6];
+	u32 cs, bw;
+
+	if (of_property_read_u32(np, "reg", &bank))
+		return -EINVAL;
+	if (of_property_read_u32(np, "reg-io-width", &width))
+		width = 1;
+	if (of_property_read_u32(np, "samsung,srom-page-mode", &pmc))
+		pmc = 0;
+	if (of_property_read_u32_array(np, "samsung,srom-timing", timing,
+				       ARRAY_SIZE(timing)))
+		return -EINVAL;
+
+	bank *= 4; /* Convert bank into shift/offset */
+
+	cs = 1 << EXYNOS_SROM_BW__BYTEENABLE__SHIFT;
+	if (width == 2)
+		cs |= 1 << EXYNOS_SROM_BW__DATAWIDTH__SHIFT;
+
+	bw = __raw_readl(srom->reg_base + EXYNOS_SROM_BW);
+	bw = (bw & ~(EXYNOS_SROM_BW__CS_MASK << bank)) | (cs << bank);
+	__raw_writel(bw, srom->reg_base + EXYNOS_SROM_BW);
+
+	__raw_writel((pmc << EXYNOS_SROM_BCX__PMC__SHIFT) |
+		    (timing[0] << EXYNOS_SROM_BCX__TACP__SHIFT) |
+		    (timing[1] << EXYNOS_SROM_BCX__TCAH__SHIFT) |
+		    (timing[2] << EXYNOS_SROM_BCX__TCOH__SHIFT) |
+		    (timing[3] << EXYNOS_SROM_BCX__TACC__SHIFT) |
+		    (timing[4] << EXYNOS_SROM_BCX__TCOS__SHIFT) |
+		    (timing[5] << EXYNOS_SROM_BCX__TACS__SHIFT),
+		    srom->reg_base + EXYNOS_SROM_BC0 + bank);
+
+	return 0;
+}
+
 static int exynos_srom_probe(struct platform_device *pdev)
 {
-	struct device_node *np;
+	struct device_node *np, *child;
 	struct exynos_srom *srom;
 	struct device *dev = &pdev->dev;
+	bool bad_bank_config = false;
 
 	np = dev->of_node;
 	if (!np) {
@@ -100,7 +141,23 @@ static int exynos_srom_probe(struct platform_device *pdev)
 		return -ENOMEM;
 	}
 
-	return 0;
+	for_each_child_of_node(np, child) {
+		if (exynos_srom_configure_bank(srom, child)) {
+			dev_err(dev,
+				"Could not decode bank configuration for %s\n",
+				child->name);
+			bad_bank_config = true;
+		}
+	}
+
+	/*
+	 * If any bank failed to configure, we still provide suspend/resume,
+	 * but do not probe child devices
+	 */
+	if (bad_bank_config)
+		return 0;
+
+	return of_platform_populate(np, NULL, NULL, dev);
 }
 
 static int exynos_srom_remove(struct platform_device *pdev)
-- 
2.4.4

[PATCH v6 3/4] drivers: exynos-srom: Add support for bank configuration

[Krzysztof Kozlowski]

On 05.11.2015 21:03, Pavel Fedin wrote:
> Implement handling properties in subnodes and adding child devices to the
> system. Child devices will not be added if configuration fails.
> 
> Since the driver now does more than suspend-resume support, dependency on
> CONFIG_PM is removed.
> 
> Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
> ---
>  arch/arm/mach-exynos/Kconfig      |  2 +-
>  drivers/soc/samsung/Kconfig       |  2 +-
>  drivers/soc/samsung/exynos-srom.c | 61 +++++++++++++++++++++++++++++++++++++--
>  3 files changed, 61 insertions(+), 4 deletions(-)


Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

Best regards,
Krzysztof

[PATCH v6 4/4] ARM: dts: Add Ethernet chip to SMDK5410

[Pavel Fedin]

The chip is smsc9115, connected via SROMc bank 3. Additionally, some GPIO
initialization is required.

Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
---
 arch/arm/boot/dts/exynos5410-smdk5410.dts | 41 +++++++++++++++++++++++++++++++
 arch/arm/boot/dts/exynos5410.dtsi         |  6 +++++
 2 files changed, 47 insertions(+)

diff --git a/arch/arm/boot/dts/exynos5410-smdk5410.dts b/arch/arm/boot/dts/exynos5410-smdk5410.dts
index cebeaab..373abf7 100644
--- a/arch/arm/boot/dts/exynos5410-smdk5410.dts
+++ b/arch/arm/boot/dts/exynos5410-smdk5410.dts
@@ -11,6 +11,7 @@
 
 /dts-v1/;
 #include "exynos5410.dtsi"
+#include <dt-bindings/interrupt-controller/irq.h>
 / {
 	model = "Samsung SMDK5410 board based on EXYNOS5410";
 	compatible = "samsung,smdk5410", "samsung,exynos5410", "samsung,exynos5";
@@ -61,6 +62,46 @@
 	disable-wp;
 };
 
+&pinctrl_0 {
+	srom_ctl: srom-ctl {
+		samsung,pins = "gpy0-3", "gpy0-4", "gpy0-5",
+			       "gpy1-0", "gpy1-1", "gpy1-2", "gpy1-3";
+		samsung,pin-function = <2>;
+		samsung,pin-drv = <0>;
+	};
+
+	srom_ebi: srom-ebi {
+		samsung,pins = "gpy3-0", "gpy3-1", "gpy3-2", "gpy3-3",
+			       "gpy3-4", "gpy3-5", "gpy3-6", "gpy3-7",
+			       "gpy5-0", "gpy5-1", "gpy5-2", "gpy5-3",
+			       "gpy5-4", "gpy5-5", "gpy5-6", "gpy5-7",
+			       "gpy6-0", "gpy6-1", "gpy6-2", "gpy6-3",
+			       "gpy6-4", "gpy6-5", "gpy6-6", "gpy6-7";
+		samsung,pin-function = <2>;
+		samsung,pin-pud = <3>;
+		samsung,pin-drv = <0>;
+	};
+};
+
+&sromc {
+	pinctrl-names = "default";
+	pinctrl-0 = <&srom_ctl>, <&srom_ebi>;
+
+	ethernet at 3 {
+		compatible = "smsc,lan9115";
+		reg = <3 0 0x10000>;
+		phy-mode = "mii";
+		interrupt-parent = <&gpx0>;
+		interrupts = <5 IRQ_TYPE_LEVEL_LOW>;
+		reg-io-width = <2>;
+		smsc,irq-push-pull;
+		smsc,force-internal-phy;
+
+		samsung,srom-page-mode = <1>;
+		samsung,srom-timing = <9 12 1 9 1 1>;
+	};
+};
+
 &uart0 {
 	status = "okay";
 };
diff --git a/arch/arm/boot/dts/exynos5410.dtsi b/arch/arm/boot/dts/exynos5410.dtsi
index e2b58f8..9cfb814 100644
--- a/arch/arm/boot/dts/exynos5410.dtsi
+++ b/arch/arm/boot/dts/exynos5410.dtsi
@@ -104,6 +104,12 @@
 		sromc: sromc at 12250000 {
 			compatible = "samsung,exynos-srom";
 			reg = <0x12250000 0x14>;
+			#address-cells = <2>;
+			#size-cells = <1>;
+			ranges = <0 0 0x04000000 0x20000
+				  1 0 0x05000000 0x20000
+				  2 0 0x06000000 0x20000
+				  3 0 0x07000000 0x20000>;
 		};
 
 		pmu_system_controller: system-controller at 10040000 {
-- 
2.4.4

[PATCH v6 4/4] ARM: dts: Add Ethernet chip to SMDK5410

[Krzysztof Kozlowski]

On 05.11.2015 21:03, Pavel Fedin wrote:
> The chip is smsc9115, connected via SROMc bank 3. Additionally, some GPIO
> initialization is required.
> 
> Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
> ---
>  arch/arm/boot/dts/exynos5410-smdk5410.dts | 41 +++++++++++++++++++++++++++++++
>  arch/arm/boot/dts/exynos5410.dtsi         |  6 +++++
>  2 files changed, 47 insertions(+)


Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

Best regards,
Krzysztof