[PATCH v5 08/11] arm: dts: qcom: Add #power-domain-cells property

Rajendra Nayak rnayak at codeaurora.org
Fri Apr 24 03:55:02 PDT 2015


On 04/24/2015 03:15 PM, Ulf Hansson wrote:
> On 14 April 2015 at 15:12, Rajendra Nayak <rnayak at codeaurora.org> wrote:
>> msm8974 has gcc and mmcc nodes, and apq8084 has a gcc node which
>> implement gdsc powerdomains. Add the #power-domain-cells property
>> to them.
>>
>> Signed-off-by: Rajendra Nayak <rnayak at codeaurora.org>
>> ---
>>   arch/arm/boot/dts/qcom-apq8084.dtsi | 1 +
>>   arch/arm/boot/dts/qcom-msm8974.dtsi | 2 ++
>>   2 files changed, 3 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/qcom-apq8084.dtsi b/arch/arm/boot/dts/qcom-apq8084.dtsi
>> index 1f130bc..55c281c 100644
>> --- a/arch/arm/boot/dts/qcom-apq8084.dtsi
>> +++ b/arch/arm/boot/dts/qcom-apq8084.dtsi
>> @@ -183,6 +183,7 @@
>>                          compatible = "qcom,gcc-apq8084";
>>                          #clock-cells = <1>;
>>                          #reset-cells = <1>;
>> +                       #power-domain-cells = <1>;
>
> So the PM domain will be apart of the clock-controller. That's a bit
> odd, but I guess the hardware is like that!?

Yes, the gdscs are all part of GCC controller.

>
> Anyway, what I fail to understand from this patchset is who will be
> the actual consumer of the PM domain? In other words, what devices
> will hold the below property in its DT node?
>
> power_domains = <phandle index>;
>
> This is needed for genpd to have the device at probe time, attached to
> its PM domain.

Any device which belongs to the collapsible power domain (gdsc)
Examples are graphics, camera, video encode/decode block (venus) etc

>
>>                          reg = <0xfc400000 0x4000>;
>>                  };
>>
>> diff --git a/arch/arm/boot/dts/qcom-msm8974.dtsi b/arch/arm/boot/dts/qcom-msm8974.dtsi
>> index e265ec1..6184d32 100644
>> --- a/arch/arm/boot/dts/qcom-msm8974.dtsi
>> +++ b/arch/arm/boot/dts/qcom-msm8974.dtsi
>> @@ -179,6 +179,7 @@
>>                          compatible = "qcom,gcc-msm8974";
>>                          #clock-cells = <1>;
>>                          #reset-cells = <1>;
>> +                       #power-domain-cells = <1>;
>>                          reg = <0xfc400000 0x4000>;
>>                  };
>>
>> @@ -186,6 +187,7 @@
>>                          compatible = "qcom,mmcc-msm8974";
>>                          #clock-cells = <1>;
>>                          #reset-cells = <1>;
>> +                       #power-domain-cells = <1>;
>>                          reg = <0xfd8c0000 0x6000>;
>>                  };
>>
>
> Kind regards
> Uffe
>

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