2019-06-04 12:31:04

by Niklas Cassel

Subject: [PATCH] arm64: dts: msm8996: fix PSCI entry-latency-us

The current entry-latency-us is too short.
The proper way to convert between the device tree properties
from the vendor tree to the upstream PSCI device tree properties is:

entry-latency-us = qcom,time-overhead - qcom,latency-us

which gives

entry-latency-us = 210 - 80 = 130

Fixes: f6aee7af59b6 ("arm64: dts: qcom: msm8996: Add PSCI cpuidle low power states")
Signed-off-by: Niklas Cassel <[email protected]>
---
arch/arm64/boot/dts/qcom/msm8996.dtsi | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/qcom/msm8996.dtsi b/arch/arm64/boot/dts/qcom/msm8996.dtsi
index b7cf2a17dcb5..e8c03b5c8990 100644
--- a/arch/arm64/boot/dts/qcom/msm8996.dtsi
+++ b/arch/arm64/boot/dts/qcom/msm8996.dtsi
@@ -174,7 +174,7 @@
compatible = "arm,idle-state";
idle-state-name = "standalone-power-collapse";
arm,psci-suspend-param = <0x00000004>;
- entry-latency-us = <40>;
+ entry-latency-us = <130>;
exit-latency-us = <80>;
min-residency-us = <300>;
};
--
2.21.0

2019-06-08 03:52:29

by Bjorn Andersson

Subject: Re: [PATCH] arm64: dts: msm8996: fix PSCI entry-latency-us

On Tue 04 Jun 05:29 PDT 2019, Niklas Cassel wrote:

> The current entry-latency-us is too short.
> The proper way to convert between the device tree properties
> from the vendor tree to the upstream PSCI device tree properties is:
>
> entry-latency-us = qcom,time-overhead - qcom,latency-us
>
> which gives
>
> entry-latency-us = 210 - 80 = 130
>
> Fixes: f6aee7af59b6 ("arm64: dts: qcom: msm8996: Add PSCI cpuidle low power states")
> Signed-off-by: Niklas Cassel <[email protected]>

Thanks Niklas

Applied,
Bjorn

> ---
> arch/arm64/boot/dts/qcom/msm8996.dtsi | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm64/boot/dts/qcom/msm8996.dtsi b/arch/arm64/boot/dts/qcom/msm8996.dtsi
> index b7cf2a17dcb5..e8c03b5c8990 100644
> --- a/arch/arm64/boot/dts/qcom/msm8996.dtsi
> +++ b/arch/arm64/boot/dts/qcom/msm8996.dtsi
> @@ -174,7 +174,7 @@
> compatible = "arm,idle-state";
> idle-state-name = "standalone-power-collapse";
> arm,psci-suspend-param = <0x00000004>;
> - entry-latency-us = <40>;
> + entry-latency-us = <130>;
> exit-latency-us = <80>;
> min-residency-us = <300>;
> };
> --
> 2.21.0
>