2018-08-09 20:11:17

by Heiko Stuebner

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Subject: Re: [PATCH] arm64: dts: rockchip: Add idle-states to device tree for rk3399

Am Mittwoch, 6. Juli 2016, 10:20:54 CEST schrieb Caesar Wang:
> As the rk3399 ATF had been supported on ARM github [0], so we can add
> idle-states for rk3399.
> This patch adds idle-states bindings data collected through tests
> experiments (latency and energy consumption) on rk3399 evb2 board.
>
> You can see detail idle-states definitions on document [1].
>
> * arm,psci-suspend-param: power_state parameter to pass to the PSCI
> suspend call.
> * entry-latency: Worst case latency required to enter the idle state. The
> exit-latency may be guaranteed only after entry-latency has passed.
> * min-residency: Minimum period, including preparation and entry, for a
> given idle state to be worthwhile energywise
> * min-residency: Minimum period, including preparation and entry, for a
> given idle state to be worthwhile energywise.
>
> [0]:
> https://github.com/ARM-software/arm-trusted-firmware
> [1]:
> Documentation/devicetree/bindings/arm/psci.txt
> Documentation/devicetree/bindings/arm/idle-states.txt
>
> Signed-off-by: Caesar Wang <[email protected]>

Looks like this patch slipped through the cracks and nobody reposted
them over time.


> arch/arm64/boot/dts/rockchip/rk3399.dtsi | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
> index a6dd623..12ce265 100644
> --- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi
> +++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
> @@ -101,6 +101,18 @@
> };
> };
>
> + idle-states {
> + entry-method = "psci";
> + cpu_sleep: cpu-sleep-0 {
> + compatible = "arm,idle-state";
> + local-timer-stop;
> + arm,psci-suspend-param = <0x0010000>;
> + entry-latency-us = <350>;
> + exit-latency-us = <600>;
> + min-residency-us = <1150>;

Looking at the chromeos kernel, there are some more patches adapting
this idle-state to use different timings.

There also was a cluster-idle state added for a while but that seems to
cause audio issues according to the CrOS history.

In any case, I'll try to look at this shortly.


Heiko




2018-08-12 16:29:15

by Tao Huang

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Subject: Re: [PATCH] arm64: dts: rockchip: Add idle-states to device tree for rk3399

Hi Heiko:

On 2018年08月10日 04:09, Heiko Stuebner wrote:
> Am Mittwoch, 6. Juli 2016, 10:20:54 CEST schrieb Caesar Wang:
>
>> arch/arm64/boot/dts/rockchip/rk3399.dtsi | 18 ++++++++++++++++++
>> 1 file changed, 18 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
>> index a6dd623..12ce265 100644
>> --- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi
>> +++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
>> @@ -101,6 +101,18 @@
>> };
>> };
>>
>> + idle-states {
>> + entry-method = "psci";
>> + cpu_sleep: cpu-sleep-0 {
>> + compatible = "arm,idle-state";
>> + local-timer-stop;
>> + arm,psci-suspend-param = <0x0010000>;
>> + entry-latency-us = <350>;
>> + exit-latency-us = <600>;
>> + min-residency-us = <1150>;
> Looking at the chromeos kernel, there are some more patches adapting
> this idle-state to use different timings.
Yes, we have another values. So the values of this patch are wrong.
>
> There also was a cluster-idle state added for a while but that seems to
> cause audio issues according to the CrOS history.

DMA or Audio driver should add PM_QOS_CPU_DMA_LATENCY or other methods to avoid the effects of idle.
Idle itself is good.

Thanks!


2018-08-13 08:50:37

by Heiko Stuebner

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Subject: Re: [PATCH] arm64: dts: rockchip: Add idle-states to device tree for rk3399

Hi Tao,

Am Sonntag, 12. August 2018, 18:24:45 CEST schrieb Tao Huang:
> On 2018年08月10日 04:09, Heiko Stuebner wrote:
> > Am Mittwoch, 6. Juli 2016, 10:20:54 CEST schrieb Caesar Wang:
> >
> >> arch/arm64/boot/dts/rockchip/rk3399.dtsi | 18 ++++++++++++++++++
> >> 1 file changed, 18 insertions(+)
> >>
> >> diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
> >> index a6dd623..12ce265 100644
> >> --- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi
> >> +++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
> >> @@ -101,6 +101,18 @@
> >> };
> >> };
> >>
> >> + idle-states {
> >> + entry-method = "psci";
> >> + cpu_sleep: cpu-sleep-0 {
> >> + compatible = "arm,idle-state";
> >> + local-timer-stop;
> >> + arm,psci-suspend-param = <0x0010000>;
> >> + entry-latency-us = <350>;
> >> + exit-latency-us = <600>;
> >> + min-residency-us = <1150>;
> > Looking at the chromeos kernel, there are some more patches adapting
> > this idle-state to use different timings.
> Yes, we have another values. So the values of this patch are wrong.
> >
> > There also was a cluster-idle state added for a while but that seems to
> > cause audio issues according to the CrOS history.
>
> DMA or Audio driver should add PM_QOS_CPU_DMA_LATENCY or other methods to avoid the effects of idle.
> Idle itself is good.

Thanks for the clarification. Do you know if some from Rockchip plans
on submitting a new version of the patch with changed timings and
cluster-sleep?

Otherwise I can also just pull the values from the vendor kernel so that
we get idle states in mainline as well.


Thanks
Heiko



2018-08-13 09:11:34

by Tao Huang

[permalink] [raw]
Subject: Re: [PATCH] arm64: dts: rockchip: Add idle-states to device tree for rk3399

On 2018年08月13日 16:25, Heiko Stuebner wrote:
> Hi Tao,
>
> Am Sonntag, 12. August 2018, 18:24:45 CEST schrieb Tao Huang:
>> On 2018年08月10日 04:09, Heiko Stuebner wrote:
>>> Am Mittwoch, 6. Juli 2016, 10:20:54 CEST schrieb Caesar Wang:
>>>
>>>> arch/arm64/boot/dts/rockchip/rk3399.dtsi | 18 ++++++++++++++++++
>>>> 1 file changed, 18 insertions(+)
>>>>
>>>> diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
>>>> index a6dd623..12ce265 100644
>>>> --- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi
>>>> +++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
>>>> @@ -101,6 +101,18 @@
>>>> };
>>>> };
>>>>
>>>> + idle-states {
>>>> + entry-method = "psci";
>>>> + cpu_sleep: cpu-sleep-0 {
>>>> + compatible = "arm,idle-state";
>>>> + local-timer-stop;
>>>> + arm,psci-suspend-param = <0x0010000>;
>>>> + entry-latency-us = <350>;
>>>> + exit-latency-us = <600>;
>>>> + min-residency-us = <1150>;
>>> Looking at the chromeos kernel, there are some more patches adapting
>>> this idle-state to use different timings.
>> Yes, we have another values. So the values of this patch are wrong.
>>> There also was a cluster-idle state added for a while but that seems to
>>> cause audio issues according to the CrOS history.
>> DMA or Audio driver should add PM_QOS_CPU_DMA_LATENCY or other methods to avoid the effects of idle.
>> Idle itself is good.
> Thanks for the clarification. Do you know if some from Rockchip plans
> on submitting a new version of the patch with changed timings and
> cluster-sleep?

Okay. I will arrange engineer to submit the patch.