Re: [PATCH 1/2] ARM: dts: imx7s: enable cpuidle driver

From: Shawn Guo
Date: Sun Sep 02 2018 - 21:17:41 EST


On Wed, Aug 29, 2018 at 01:00:46PM +0800, Anson Huang wrote:
> Enable cpuidle for i.MX7S/D using generic ARM cpuidle
> driver, below 2 idle states enabled:
>
> 1. ARM WFI;
> 2. SoC WAIT mode.
>
> Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> ---
> arch/arm/boot/dts/imx7d.dtsi | 1 +
> arch/arm/boot/dts/imx7s.dtsi | 14 ++++++++++++++
> 2 files changed, 15 insertions(+)
>
> diff --git a/arch/arm/boot/dts/imx7d.dtsi b/arch/arm/boot/dts/imx7d.dtsi
> index 7cbc2ff..4d0d0f6 100644
> --- a/arch/arm/boot/dts/imx7d.dtsi
> +++ b/arch/arm/boot/dts/imx7d.dtsi
> @@ -20,6 +20,7 @@
> reg = <1>;
> clock-frequency = <996000000>;
> operating-points-v2 = <&cpu0_opp_table>;
> + cpu-idle-states = <&CPU_SLEEP>;
> };
> };
>
> diff --git a/arch/arm/boot/dts/imx7s.dtsi b/arch/arm/boot/dts/imx7s.dtsi
> index 93884ce..cf5570b 100644
> --- a/arch/arm/boot/dts/imx7s.dtsi
> +++ b/arch/arm/boot/dts/imx7s.dtsi
> @@ -54,6 +54,19 @@
> #address-cells = <1>;
> #size-cells = <0>;
>
> + idle-states {
> + entry-method = "psci";
> +
> + CPU_SLEEP: WAIT {

I understand uppercase is allowed, but we conventionally use lowercase
for label and node name. Can we do something like below?

cpu_sleep_wait: cpu-sleep-wait {
...
}

Shawn

> + compatible = "arm,idle-state";
> + arm,psci-suspend-param = <0x0010000>;
> + local-timer-stop;
> + entry-latency-us = <100>;
> + exit-latency-us = <50>;
> + min-residency-us = <1000>;
> + };
> + };
> +
> cpu0: cpu@0 {
> compatible = "arm,cortex-a7";
> device_type = "cpu";
> @@ -61,6 +74,7 @@
> clock-frequency = <792000000>;
> clock-latency = <61036>; /* two CLK32 periods */
> clocks = <&clks IMX7D_CLK_ARM>;
> + cpu-idle-states = <&CPU_SLEEP>;
> };
> };
>
> --
> 2.7.4
>
>
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