Re: [PATCH 3/7] arm64: dts: qcom: sm8550: Fix up CPU idle states

From: Dmitry Baryshkov
Date: Wed Aug 30 2023 - 17:18:41 EST


On Wed, 30 Aug 2023 at 23:35, Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> wrote:
>
> On 30.08.2023 22:13, Dmitry Baryshkov wrote:
> > On Wed, 30 Aug 2023 at 22:04, Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> wrote:
> >>
> >> The idle residency times are largely too low according to the vendor
> >> kernel (maybe they came from an earlier release or something), especially
> >> for the prime X2 core. Fix them.
> >>
> >> Fixes: ffc50b2d3828 ("arm64: dts: qcom: Add base SM8550 dtsi")
> >> Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
> >> ---
> >> arch/arm64/boot/dts/qcom/sm8550.dtsi | 32 +++++++++++++++++++++-----------
> >> 1 file changed, 21 insertions(+), 11 deletions(-)
> >>
> >> diff --git a/arch/arm64/boot/dts/qcom/sm8550.dtsi b/arch/arm64/boot/dts/qcom/sm8550.dtsi
> >> index d115960bdeec..c21ba6afa752 100644
> >> --- a/arch/arm64/boot/dts/qcom/sm8550.dtsi
> >> +++ b/arch/arm64/boot/dts/qcom/sm8550.dtsi
> >> @@ -283,9 +283,9 @@ LITTLE_CPU_SLEEP_0: cpu-sleep-0-0 {
> >> compatible = "arm,idle-state";
> >> idle-state-name = "silver-rail-power-collapse";
> >> arm,psci-suspend-param = <0x40000004>;
> >> - entry-latency-us = <800>;
> >> + entry-latency-us = <550>;
> >> exit-latency-us = <750>;
> >> - min-residency-us = <4090>;
> >> + min-residency-us = <6700>;
> >> local-timer-stop;
> >> };
> >>
> >> @@ -294,8 +294,18 @@ BIG_CPU_SLEEP_0: cpu-sleep-1-0 {
> >> idle-state-name = "gold-rail-power-collapse";
> >> arm,psci-suspend-param = <0x40000004>;
> >> entry-latency-us = <600>;
> >> - exit-latency-us = <1550>;
> >> - min-residency-us = <4791>;
> >> + exit-latency-us = <1300>;
> >> + min-residency-us = <8136>;
> >> + local-timer-stop;
> >> + };
> >> +
> >> + PRIME_CPU_SLEEP_0: cpu-sleep-2-0 {
> >> + compatible = "arm,idle-state";
> >> + idle-state-name = "gold-plus-rail-power-collapse";
> >> + arm,psci-suspend-param = <0x40000004>;
> >> + entry-latency-us = <500>;
> >> + exit-latency-us = <1350>;
> >> + min-residency-us = <7480>;
> >> local-timer-stop;
> >
> > This isn't only fixing the time properties, but also adds the whole
> > new sleep state!
> It does add a "new" sleep state with the exact same parameters,
> the only thing being that it's exclusive to the prime core and
> the only thing that differs is the residencies.

Then it should be stated in the commit message.

With that fixed,

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>


--
With best wishes
Dmitry