Re: [PATCH 2/2] arm64: dts: qcom: sm8550: Additionally manage MXC power domain in camcc

Luca Weiss
2025-03-13T07:52:09Z

Hi Taniya,

On Thu Mar 13, 2025 at 5:39 AM CET, Taniya Das wrote:
>
>
> On 3/4/2025 2:10 PM, Dmitry Baryshkov wrote:
>> On Tue, 4 Mar 2025 at 09:37, Vladimir Zapolskiy
>> <vladimir.zapolskiy@linaro.org> wrote:
>>>
>>> On 3/4/25 01:53, Dmitry Baryshkov wrote:
>>>> On Tue, Mar 04, 2025 at 12:55:21AM +0200, Vladimir Zapolskiy wrote:
>>>>> SM8550 Camera Clock Controller shall enable both MXC and MMCX power
>>>>> domains.
>>>>
>>>> Are those really required to access the registers of the cammcc? Or is
>>>> one of those (MXC?) required to setup PLLs? Also, is this applicable
>>>> only to sm8550 or to other similar clock controllers?
>>>
>>> Due to the described problem I experience a fatal CPU stall on SM8550-QRD,
>>> not on any SM8450 or SM8650 powered board for instance, however it does
>>> not exclude an option that the problem has to be fixed for other clock
>>> controllers, but it's Qualcomm to confirm any other touched platforms,
>>
>> Please work with Taniya to identify used power domains.
>>
>
> CAMCC requires both MMCX and MXC to be functional.

Could you check whether any clock controllers on SM6350/SM7225 (Bitra)
need multiple power domains, or in general which clock controller uses
which power domain.

That SoC has camcc, dispcc, gcc, gpucc, npucc and videocc.

That'd be highly appreciated since I've been hitting weird issues there
that could be explained by some missing power domains.

Regards
Luca

>
>>> for instance x1e80100-camcc has it resolved right at the beginning.
>>>
>>> To my understanding here 'required-opps' shall also be generalized, so
>>> the done copy from x1e80100-camcc was improper, and the latter dt-binding
>>> should be fixed.
>>
>> Yes
>>
>
> required-opps is not mandatory for MXC as we ensure that MxC would never
> hit retention.
>
> https://lore.kernel.org/r/20240625-avoid_mxc_retention-v2-1-af9c2f549a5f@quicinc.com
>
>
>>
>>