diff mbox

[v6,6/7] drivers: cpuidle: initialize big.LITTLE driver through DT

Message ID 1405958786-17243-7-git-send-email-lorenzo.pieralisi@arm.com
State New
Headers show

Commit Message

Lorenzo Pieralisi July 21, 2014, 4:06 p.m. UTC 
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 big.LITTLE CPUidle driver to dynamically
initialize idle states data through the updated device tree source file.

Cc: Chander Kashyap <chander.kashyap@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
---
 arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts | 23 ++++++++++++++++
 drivers/cpuidle/Kconfig.arm                |  1 +
 drivers/cpuidle/cpuidle-big_little.c       | 43 +++++++++++++++---------------
 3 files changed, 46 insertions(+), 21 deletions(-)

Comments

Catalin Marinas July 23, 2014, 4:26 p.m. UTC | #1 
On Mon, Jul 21, 2014 at 05:06:25PM +0100, Lorenzo Pieralisi wrote:
> 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 big.LITTLE CPUidle driver to dynamically
> initialize idle states data through the updated device tree source file.
> 
> Cc: Chander Kashyap <chander.kashyap@linaro.org>
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

I think for this patch (and the exynos one) we should still allow the
driver to work fine with old DT. Basically if the information is not in
DT, fall back to the original static definitions.
Lorenzo Pieralisi Aug. 6, 2014, 9:02 a.m. UTC | #2 
On Wed, Jul 23, 2014 at 05:26:26PM +0100, Catalin Marinas wrote:
> On Mon, Jul 21, 2014 at 05:06:25PM +0100, Lorenzo Pieralisi wrote:
> > 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 big.LITTLE CPUidle driver to dynamically
> > initialize idle states data through the updated device tree source file.
> > 
> > Cc: Chander Kashyap <chander.kashyap@linaro.org>
> > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> 
> I think for this patch (and the exynos one) we should still allow the
> driver to work fine with old DT. Basically if the information is not in
> DT, fall back to the original static definitions.

Yes, this makes sense, I will implement the fall-back mechanism on v7,
that should be final. If in the meanwhile Samsung guys have time to
test the Exynos patch that would be very appreciated.

Thanks,
Lorenzo
diff mbox

Patch

diff --git a/arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts b/arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts
index a25c262..d61da86 100644
--- a/arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts
+++ b/arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts
@@ -38,6 +38,7 @@ 
 			compatible = "arm,cortex-a15";
 			reg = <0>;
 			cci-control-port = <&cci_control1>;
+			cpu-idle-states = <&CLUSTER_SLEEP_BIG>;
 		};
 
 		cpu1: cpu@1 {
@@ -45,6 +46,7 @@ 
 			compatible = "arm,cortex-a15";
 			reg = <1>;
 			cci-control-port = <&cci_control1>;
+			cpu-idle-states = <&CLUSTER_SLEEP_BIG>;
 		};
 
 		cpu2: cpu@2 {
@@ -52,6 +54,7 @@ 
 			compatible = "arm,cortex-a7";
 			reg = <0x100>;
 			cci-control-port = <&cci_control2>;
+			cpu-idle-states = <&CLUSTER_SLEEP_LITTLE>;
 		};
 
 		cpu3: cpu@3 {
@@ -59,6 +62,7 @@ 
 			compatible = "arm,cortex-a7";
 			reg = <0x101>;
 			cci-control-port = <&cci_control2>;
+			cpu-idle-states = <&CLUSTER_SLEEP_LITTLE>;
 		};
 
 		cpu4: cpu@4 {
@@ -66,6 +70,25 @@ 
 			compatible = "arm,cortex-a7";
 			reg = <0x102>;
 			cci-control-port = <&cci_control2>;
+			cpu-idle-states = <&CLUSTER_SLEEP_LITTLE>;
+		};
+
+		idle-states {
+			CLUSTER_SLEEP_BIG: cluster-sleep-big {
+				compatible = "arm,idle-state";
+				local-timer-stop;
+				entry-latency-us = <1000>;
+				exit-latency-us = <700>;
+				min-residency-us = <3500>;
+			};
+
+			CLUSTER_SLEEP_LITTLE: cluster-sleep-little {
+				compatible = "arm,idle-state";
+				local-timer-stop;
+				entry-latency-us = <1000>;
+				exit-latency-us = <500>;
+				min-residency-us = <3000>;
+			};
 		};
 	};
 
diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
index b6d69e8..a9b089c 100644
--- a/drivers/cpuidle/Kconfig.arm
+++ b/drivers/cpuidle/Kconfig.arm
@@ -12,6 +12,7 @@  config ARM_BIG_LITTLE_CPUIDLE
 	depends on ARCH_VEXPRESS_TC2_PM
 	select ARM_CPU_SUSPEND
 	select CPU_IDLE_MULTIPLE_DRIVERS
+	select DT_IDLE_STATES
 	help
 	  Select this option to enable CPU idle driver for big.LITTLE based
 	  ARM systems. Driver manages CPUs coordination through MCPM and
diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c
index b45fc62..0a88480 100644
--- a/drivers/cpuidle/cpuidle-big_little.c
+++ b/drivers/cpuidle/cpuidle-big_little.c
@@ -24,6 +24,8 @@ 
 #include <asm/smp_plat.h>
 #include <asm/suspend.h>
 
+#include "dt_idle_states.h"
+
 static int bl_enter_powerdown(struct cpuidle_device *dev,
 			      struct cpuidle_driver *drv, int idx);
 
@@ -61,32 +63,12 @@  static struct cpuidle_driver bl_idle_little_driver = {
 	.name = "little_idle",
 	.owner = THIS_MODULE,
 	.states[0] = ARM_CPUIDLE_WFI_STATE,
-	.states[1] = {
-		.enter			= bl_enter_powerdown,
-		.exit_latency		= 700,
-		.target_residency	= 2500,
-		.flags			= CPUIDLE_FLAG_TIME_VALID |
-					  CPUIDLE_FLAG_TIMER_STOP,
-		.name			= "C1",
-		.desc			= "ARM little-cluster power down",
-	},
-	.state_count = 2,
 };
 
 static struct cpuidle_driver bl_idle_big_driver = {
 	.name = "big_idle",
 	.owner = THIS_MODULE,
 	.states[0] = ARM_CPUIDLE_WFI_STATE,
-	.states[1] = {
-		.enter			= bl_enter_powerdown,
-		.exit_latency		= 500,
-		.target_residency	= 2000,
-		.flags			= CPUIDLE_FLAG_TIME_VALID |
-					  CPUIDLE_FLAG_TIMER_STOP,
-		.name			= "C1",
-		.desc			= "ARM big-cluster power down",
-	},
-	.state_count = 2,
 };
 
 /*
@@ -165,7 +147,8 @@  static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int cpu_id)
 
 static int __init bl_idle_init(void)
 {
-	int ret;
+	int ret, i;
+	struct cpuidle_driver *drv;
 
 	/*
 	 * Initialize the driver just for a compliant set of machines
@@ -187,6 +170,24 @@  static int __init bl_idle_init(void)
 	if (ret)
 		goto out_uninit_little;
 
+	 /* Start at index 1, index 0 standard WFI */
+	ret = dt_init_idle_driver(&bl_idle_big_driver, 1);
+	if (ret)
+		goto out_uninit_big;
+
+	 /* Start at index 1, index 0 standard WFI */
+	ret = dt_init_idle_driver(&bl_idle_little_driver, 1);
+	if (ret)
+		goto out_uninit_big;
+
+	drv = &bl_idle_big_driver;
+	for (i = 1; i < drv->state_count; i++)
+		drv->states[i].enter = bl_enter_powerdown;
+
+	drv = &bl_idle_little_driver;
+	for (i = 1; i < drv->state_count; i++)
+		drv->states[i].enter = bl_enter_powerdown;
+
 	ret = cpuidle_register(&bl_idle_little_driver, NULL);
 	if (ret)
 		goto out_uninit_big;