On Wed, Sep 03, 2014 at 02:32:14PM +0100, Daniel Lezcano wrote:

On 09/01/2014 05:28 PM, Lorenzo Pieralisi wrote:

quoted

With the introduction of DT based idle states, CPUidle drivers for
ARM can now initialize idle states data through properties in the device
tree.

This patch adds code to the Exynos CPUidle driver to dynamically
initialize idle states data through the updated device tree source
files.

Cc: Chander Kashyap <redacted>
Cc: Kukjin Kim <redacted>
Cc: Tomasz Figa <redacted>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Lorenzo Pieralisi <redacted>

Acked-by: Daniel Lezcano <redacted>

Thanks Daniel !

This patch has a dependency:

http://lists.infradead.org/pipermail/linux-arm-kernel/2014-July/274179.html

Bartolomiej do you plan to merge the patch above ?

This patch needs also testing, I do not have Exynos boards so I only
compile tested it.

Lorenzo

quoted

---
  arch/arm/boot/dts/exynos4210.dtsi | 11 +++++++++++
  arch/arm/boot/dts/exynos5250.dtsi | 11 +++++++++++
  drivers/cpuidle/Kconfig.arm       |  1 +
  drivers/cpuidle/cpuidle-exynos.c  | 18 +++++++++++++++++-
  4 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/exynos4210.dtsi b/arch/arm/boot/dts/exynos4210.dtsi
index eab7c7b..69fd1a0 100644
--- a/arch/arm/boot/dts/exynos4210.dtsi
+++ b/arch/arm/boot/dts/exynos4210.dtsi

@@ -48,12 +48,23 @@
  			device_type = "cpu";
  			compatible = "arm,cortex-a9";
  			reg = <0x900>;
+			cpu-idle-states = <&CLUSTER_SLEEP_0>;
  		};

  		cpu at 901 {
  			device_type = "cpu";
  			compatible = "arm,cortex-a9";
  			reg = <0x901>;
+			cpu-idle-states = <&CLUSTER_SLEEP_0>;
+		};
+
+		idle-states {
+			CLUSTER_SLEEP_0: cluster-sleep-0 {
+				compatible = "arm,idle-state";
+				entry-latency-us = <1000>;
+				exit-latency-us = <300>;
+				min-residency-us = <100000>;
+			};
  		};
  	};

diff --git a/arch/arm/boot/dts/exynos5250.dtsi b/arch/arm/boot/dts/exynos5250.dtsi
index 492e1ef..3a758ff 100644
--- a/arch/arm/boot/dts/exynos5250.dtsi
+++ b/arch/arm/boot/dts/exynos5250.dtsi

@@ -63,12 +63,23 @@
  			compatible = "arm,cortex-a15";
  			reg = <0>;
  			clock-frequency = <1700000000>;
+			cpu-idle-states = <&CLUSTER_SLEEP_0>;
  		};
  		cpu at 1 {
  			device_type = "cpu";
  			compatible = "arm,cortex-a15";
  			reg = <1>;
  			clock-frequency = <1700000000>;
+			cpu-idle-states = <&CLUSTER_SLEEP_0>;
+		};
+
+		idle-states {
+			CLUSTER_SLEEP_0: cluster-sleep-0 {
+				compatible = "arm,idle-state";
+				entry-latency-us = <1000>;
+				exit-latency-us = <300>;
+				min-residency-us = <100000>;
+			};
  		};
  	};

diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
index e339c7f..04cc229 100644
--- a/drivers/cpuidle/Kconfig.arm
+++ b/drivers/cpuidle/Kconfig.arm

@@ -55,6 +55,7 @@ config ARM_AT91_CPUIDLE
  config ARM_EXYNOS_CPUIDLE
  	bool "Cpu Idle Driver for the Exynos processors"
  	depends on ARCH_EXYNOS
+	select DT_IDLE_STATES
  	help
  	  Select this to enable cpuidle for Exynos processors

diff --git a/drivers/cpuidle/cpuidle-exynos.c b/drivers/cpuidle/cpuidle-exynos.c
index ba9b34b..e66a426 100644
--- a/drivers/cpuidle/cpuidle-exynos.c
+++ b/drivers/cpuidle/cpuidle-exynos.c

@@ -18,6 +18,8 @@
  #include <asm/suspend.h>
  #include <asm/cpuidle.h>

+#include "dt_idle_states.h"
+
  static void (*exynos_enter_aftr)(void);

  static int exynos_enter_lowpower(struct cpuidle_device *dev,

@@ -56,13 +58,27 @@ static struct cpuidle_driver exynos_idle_driver = {
  	.safe_state_index = 0,
  };

+static const struct of_device_id exynos_idle_state_match[] __initconst = {
+	{ .compatible = "arm,idle-state",
+	  .data = exynos_enter_lowpower },
+	{ },
+};
+
  static int exynos_cpuidle_probe(struct platform_device *pdev)
  {
  	int ret;
+	struct cpuidle_driver *drv = &exynos_idle_driver;

  	exynos_enter_aftr = (void *)(pdev->dev.platform_data);

-	ret = cpuidle_register(&exynos_idle_driver, NULL);
+	/* Start at index 1, index 0 standard WFI */
+	ret = dt_init_idle_driver(drv, exynos_idle_state_match, 1);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to initialize idle states\n");
+		return ret;
+	}
+
+	ret = cpuidle_register(drv, NULL);
  	if (ret) {
  		dev_err(&pdev->dev, "failed to register cpuidle driver\n");
  		return ret;

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