2015-04-07 08:04:46

by Howard Chen

Subject: [PATCH v2] ARM: dts: mt8173: support arm64 cpuidle-dt

This patch adds an idle-states node to describe the mt8173 idle states and
also adds references to the idle-states node in all CPU nodes.

Signed-off-by: Howard Chen <[email protected]>
---
arch/arm64/boot/dts/mediatek/mt8173.dtsi | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
index 8554ec3..0d31a34 100644
--- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
@@ -48,6 +48,8 @@
device_type = "cpu";
compatible = "arm,cortex-a53";
reg = <0x000>;
+ enable-method = "psci";
+ cpu-idle-states = <&CPU_SLEEP_0>;
};

cpu1: cpu@1 {
@@ -55,6 +57,7 @@
compatible = "arm,cortex-a53";
reg = <0x001>;
enable-method = "psci";
+ cpu-idle-states = <&CPU_SLEEP_0>;
};

cpu2: cpu@100 {
@@ -62,6 +65,7 @@
compatible = "arm,cortex-a57";
reg = <0x100>;
enable-method = "psci";
+ cpu-idle-states = <&CPU_SLEEP_0>;
};

cpu3: cpu@101 {
@@ -69,6 +73,19 @@
compatible = "arm,cortex-a57";
reg = <0x101>;
enable-method = "psci";
+ cpu-idle-states = <&CPU_SLEEP_0>;
+ };
+
+ idle-states {
+ entry-method = "arm,psci";
+
+ CPU_SLEEP_0: cpu-sleep-0 {
+ compatible = "arm,idle-state";
+ arm,psci-suspend-param = <0x0010000>;
+ entry-latency-us = <639>;
+ exit-latency-us = <328>;
+ min-residency-us = <1088>;
+ };
};
};

--
1.9.1

2015-04-08 10:54:56

by Lorenzo Pieralisi

Subject: Re: [PATCH v2] ARM: dts: mt8173: support arm64 cpuidle-dt

On Tue, Apr 07, 2015 at 09:05:05AM +0100, Howard Chen wrote:
> This patch adds an idle-states node to describe the mt8173 idle states and
> also adds references to the idle-states node in all CPU nodes.
>
> Signed-off-by: Howard Chen <[email protected]>

Is copying me in too much effort to ask ?

> arch/arm64/boot/dts/mediatek/mt8173.dtsi | 17 +++++++++++++++++
> 1 file changed, 17 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> index 8554ec3..0d31a34 100644
> --- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> +++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> @@ -48,6 +48,8 @@
> device_type = "cpu";
> compatible = "arm,cortex-a53";
> reg = <0x000>;
> + enable-method = "psci";
> + cpu-idle-states = <&CPU_SLEEP_0>;

Cluster idle state vanished between v1 and v2.

?

> };
>
> cpu1: cpu@1 {
> @@ -55,6 +57,7 @@
> compatible = "arm,cortex-a53";
> reg = <0x001>;
> enable-method = "psci";
> + cpu-idle-states = <&CPU_SLEEP_0>;
> };
>
> cpu2: cpu@100 {
> @@ -62,6 +65,7 @@
> compatible = "arm,cortex-a57";
> reg = <0x100>;
> enable-method = "psci";
> + cpu-idle-states = <&CPU_SLEEP_0>;
> };
>
> cpu3: cpu@101 {
> @@ -69,6 +73,19 @@
> compatible = "arm,cortex-a57";
> reg = <0x101>;
> enable-method = "psci";
> + cpu-idle-states = <&CPU_SLEEP_0>;
> + };
> +
> + idle-states {
> + entry-method = "arm,psci";
> +
> + CPU_SLEEP_0: cpu-sleep-0 {
> + compatible = "arm,idle-state";
> + arm,psci-suspend-param = <0x0010000>;
> + entry-latency-us = <639>;
> + exit-latency-us = <328>;
> + min-residency-us = <1088>;
> + };
> };
> };

Is the arch timer still running when you enter this state ?

Apart from these remarks the patch seems fine, I wonder whether we should
merge these changes into the kernel instead of keeping these changes in
firmware for specific kernel configurations.

Lorenzo