Re: [PATCH v3 1/3] dt-bindings: clock: qcom: glymur-gcc: Add missing CX power domain

[Taniya Das]

On 7/17/2026 6:45 AM, Bjorn Andersson wrote:
> On Thu, Jul 16, 2026 at 04:42:11PM +0530, Taniya Das wrote:
>>
>>
>> On 7/16/2026 12:52 PM, Abel Vesa wrote:
>>> On 26-07-16 10:13:48, Taniya Das wrote:
>>>>
>>>>
>>>> On 7/15/2026 6:59 PM, Abel Vesa wrote:
>>>>> The GDSCs provided by the Glymur GCC are supplied by the RPMh CX power
>>>>> domain. Model that parent domain in the GCC binding so the provider can
>>>>> describe the dependency in devicetree.
>>>>>
>>>>> Add a single CX power-domain entry to the binding and make it required,
>>>>> matching the hardware description needed by the GCC node.
>>>>>
>>>>> Fixes: ee2d967030fe ("dt-bindings: clock: qcom: document the Glymur Global Clock Controller")
>>>>> Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxxxxxxxx>
>>>>> ---
>>>>>  Documentation/devicetree/bindings/clock/qcom,glymur-gcc.yaml | 8 ++++++++
>>>>>  1 file changed, 8 insertions(+)
>>>>
>>>>
>>>> Abel, I feel we should add the 'required-opps' as well which will ensure
>>>> the clock controllers minimum voltage requirement.
>>>
>>> But it was agreed in v1 that we should not add the required-opps. So we
>>> dropped it in v2.
>>>
>>
>> Okay, sorry, may be I missed that comment.
>>
>>
>>> Can you give more details to why you think it is needed ?
>>
>> My reasoning is that if a clock controller requires a rail, it is
>> preferable to explicitly specify the required operating level rather
>> than rely on system/client vote. This makes the dependency
>> self-contained and easier to reason about. Clients that require a higher
>> operating level than the clock controller's minimum requirement remain
>> free to vote for a higher level as needed.
>>
> 
> You're expressing this in generic terms, can you please provide the
> concrete example of what this would look for in the Glymur GCC case? 
> 

Yes, Bjorn, this is indeed a general requirement for a clock controller.

In Glymur I do see that CX could drop to retention corner in case there
is no vote from any subsystem and so it is better to vote from clock
controller a level above retention using the required-opps.

> What is the required-opps for the Glymur GCC?

LOW_SVS(rpmhpd_opp_low_svs) corner should be good for GCC controller.

-- 
Thanks,
Taniya Das