Re: [PATCH] arm64: dts: qcom: qcs404: Add PSCI cpuidle support

From: Amit Kucheria
Date: Tue May 07 2019 - 17:19:28 EST


On Tue, May 7, 2019 at 1:01 AM Niklas Cassel <niklas.cassel@xxxxxxxxxx> wrote:
>
> Add device bindings for CPUs to suspend using PSCI as the enable-method.
>
> Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxxxx>
> ---
> arch/arm64/boot/dts/qcom/qcs404.dtsi | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/qcom/qcs404.dtsi b/arch/arm64/boot/dts/qcom/qcs404.dtsi
> index ffedf9640af7..f9db9f3ee10c 100644
> --- a/arch/arm64/boot/dts/qcom/qcs404.dtsi
> +++ b/arch/arm64/boot/dts/qcom/qcs404.dtsi
> @@ -31,6 +31,7 @@
> reg = <0x100>;
> enable-method = "psci";
> next-level-cache = <&L2_0>;
> + cpu-idle-states = <&CPU_PC>;
> };
>
> CPU1: cpu@101 {
> @@ -39,6 +40,7 @@
> reg = <0x101>;
> enable-method = "psci";
> next-level-cache = <&L2_0>;
> + cpu-idle-states = <&CPU_PC>;
> };
>
> CPU2: cpu@102 {
> @@ -47,6 +49,7 @@
> reg = <0x102>;
> enable-method = "psci";
> next-level-cache = <&L2_0>;
> + cpu-idle-states = <&CPU_PC>;
> };
>
> CPU3: cpu@103 {
> @@ -55,12 +58,24 @@
> reg = <0x103>;
> enable-method = "psci";
> next-level-cache = <&L2_0>;
> + cpu-idle-states = <&CPU_PC>;
> };
>
> L2_0: l2-cache {
> compatible = "cache";
> cache-level = <2>;
> };
> +
> + idle-states {

entry-method="psci" property goes here. I have a patch fixing it for 410c ;-)

I don't think the psci_cpuidle_ops will even get called without this.
Did you see any changes in consumption with this patch? I was trying
to measure that before sending this out.

> + CPU_PC: pc {
> + compatible = "arm,idle-state";
> + arm,psci-suspend-param = <0x40000003>;
> + entry-latency-us = <125>;
> + exit-latency-us = <180>;
> + min-residency-us = <595>;
> + local-timer-stop;
> + };
> + };
> };
>
> firmware {
> --
> 2.21.0
>