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

Taniya Das
2025-03-13T11:57:54Z

On 3/13/2025 1:22 PM, Luca Weiss wrote:
> 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.
>

Hi Luca,

The targets you mentioned does not have any have multiple rail
dependency, but could you share the weird issues with respect to clock
controller I can take a look.

> 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
>>
>>
>>>
>>>
>