Re: [PATCH v7 1/2] arm64: dts: qcom: sm8250: sort out Iris power domains

[Konrad Dybcio]

On 6/9/26 8:00 AM, Vishnu Reddy wrote:
> 
> On 6/4/2026 9:52 PM, Dmitry Baryshkov wrote:
>> On SM8250 Iris core requires two power rails to function, MX (for PLLs)
>> and MMCX (for everything else). The commit fa245b3f06cd ("arm64: dts:
>> qcom: sm8250: Add venus DT node") added only MX power rail, but omitted
>> MMCX voltage levels.
>>
>> Add MMCX domain to the Iris device node.
>>
>> Fixes: fa245b3f06cd ("arm64: dts: qcom: sm8250: Add venus DT node")
>> Reported-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>
>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
>> ---
>>  arch/arm64/boot/dts/qcom/sm8250.dtsi | 20 ++++++++++++++------
>>  1 file changed, 14 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/sm8250.dtsi b/arch/arm64/boot/dts/qcom/sm8250.dtsi
>> index 7076720413ab..6150380795b8 100644
>> --- a/arch/arm64/boot/dts/qcom/sm8250.dtsi
>> +++ b/arch/arm64/boot/dts/qcom/sm8250.dtsi
>> @@ -4326,8 +4326,12 @@ venus: video-codec@aa00000 {
>>  			interrupts = <GIC_SPI 174 IRQ_TYPE_LEVEL_HIGH>;
>>  			power-domains = <&videocc MVS0C_GDSC>,
>>  					<&videocc MVS0_GDSC>,
>> -					<&rpmhpd RPMHPD_MX>;
>> -			power-domain-names = "venus", "vcodec0", "mx";
>> +					<&rpmhpd RPMHPD_MX>,
>> +					<&rpmhpd RPMHPD_MMCX>;
>> +			power-domain-names = "venus",
>> +					     "vcodec0",
>> +					     "mx",
>> +					     "mmcx";
> 
> With this change in place, the backwards compatibility for the incomplete
> SM8250 ABI which was merged from v5 in this series, which handles the return
> value of devm_pm_domain_attach_list(), will never be hit right? If so, we can
> remove that piece of code from the driver.

The point of backwards compatibility is that we can never assume
that the user has updated the DT (because e.g. it may be embedded in
the bootloader)

Konrad