Re: [PATCH v8 7/8] drivers: cpuidle: initialize big.LITTLE driver through DT

[Daniel Lezcano <daniel.lezcano@linaro.org>]

On 09/01/2014 05:28 PM, 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 <k.chander@samsung.com>
> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>

> ---
>   arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts | 23 +++++++++++++++++++++++
>   drivers/cpuidle/Kconfig.arm                |  1 +
>   drivers/cpuidle/cpuidle-big_little.c       | 19 +++++++++++++++++++
>   3 files changed, 43 insertions(+)
>
> diff --git a/arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts b/arch/arm/boot/dts/vexpress-v2p-ca15_a7.dts
> index a25c262..322fd15 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 = <2000>;
> +			};
> +
> +			CLUSTER_SLEEP_LITTLE: cluster-sleep-little {
> +				compatible = "arm,idle-state";
> +				local-timer-stop;
> +				entry-latency-us = <1000>;
> +				exit-latency-us = <500>;
> +				min-residency-us = <2500>;
> +			};
>   		};
>   	};
>
> diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
> index 38cff69..e339c7f 100644
> --- a/drivers/cpuidle/Kconfig.arm
> +++ b/drivers/cpuidle/Kconfig.arm
> @@ -7,6 +7,7 @@ config ARM_BIG_LITTLE_CPUIDLE
>   	depends on MCPM
>   	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 ef94c3b..85d09bc 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);
>
> @@ -73,6 +75,12 @@ static struct cpuidle_driver bl_idle_little_driver = {
>   	.state_count = 2,
>   };
>
> +static const struct of_device_id bl_idle_state_match[] __initconst = {
> +	{ .compatible = "arm,idle-state",
> +	  .data = bl_enter_powerdown },
> +	{ },
> +};
> +
>   static struct cpuidle_driver bl_idle_big_driver = {
>   	.name = "big_idle",
>   	.owner = THIS_MODULE,
> @@ -190,6 +198,17 @@ 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, bl_idle_state_match, 1);
> +	if (ret < 0)
> +		goto out_uninit_big;
> +
> +	/* Start at index 1, index 0 standard WFI */
> +	ret = dt_init_idle_driver(&bl_idle_little_driver,
> +				  bl_idle_state_match, 1);
> +	if (ret < 0)
> +		goto out_uninit_big;
> +
>   	ret = cpuidle_register(&bl_idle_little_driver, NULL);
>   	if (ret)
>   		goto out_uninit_big;
>


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