Re: [PATCH 2/3] arm64: dts: qcom: eliza: Add CX power domain to GCC

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 3/24/26 2:45 PM, Abel Vesa wrote:
> On 26-03-23 21:15:12, Bjorn Andersson wrote:
>> On Sun, Mar 22, 2026 at 06:08:20PM +0200, Abel Vesa wrote:
>>> Recent discussions off-list highlighted that the GCC should vote for the
>>> RPMh CX power domain on Qualcomm platforms.
>>
>> Your commit message should describe the problem that the patch is trying
>> to solve, not the story about how the patch came to be.
> 
> Sure. Will fix.
> 
>>
>>> Without this, RPMh may not aggregate the correct load for the CX rail,
>>
>> "may not"?
>>
>> In what case will it aggregate the client votes cast on the GDSCs
>> aggregate to anything without the power-domains property?
> 
> So my understanding was that RPMh firmware aggregates votes
> internally as it knows the actual parent-child relationship and we were
> supposed to replicate that exactly in kernel for reliability purposes.
> 
> Meaning, in theory it should know to aggregate proper load for the CX
> based on GDSCs voting, it's just that it isn't always a sure thing.
> 
> Maybe I missunderstood it though.

GDSCs are fancy on/off switches

RPMH votes must be carried out manually and in the kernel that's via
RPMHPD/RPMHCC/ICC

Konrad