Re: [PATCH 1/6] drm/msm/a6xx: Add support for Adreno 612

[Konrad Dybcio]

On 10/24/25 4:23 PM, Akhil P Oommen wrote:
> On 10/24/2025 6:46 PM, Rob Clark wrote:
>> On Fri, Oct 24, 2025 at 12:55 AM Konrad Dybcio
>> <konrad.dybcio@xxxxxxxxxxxxxxxx> wrote:
>>>
>>> On 10/24/25 12:57 AM, Akhil P Oommen wrote:
>>>> On 10/22/2025 8:43 PM, Konrad Dybcio wrote:
>>>>> On 10/17/25 7:08 PM, Akhil P Oommen wrote:
>>>>>> From: Jie Zhang <quic_jiezh@xxxxxxxxxxx>
>>>>>>
>>>>>> Add support for Adreno 612 GPU found in SM6150/QCS615 chipsets.
>>>>>> A612 falls under ADRENO_6XX_GEN1 family and is a cut down version
>>>>>> of A615 GPU.
>>>>>>
>>>>>> A612 has a new IP called Reduced Graphics Management Unit or RGMU
>>>>>> which is a small state machine which helps to toggle GX GDSC
>>>>>> (connected to CX rail) to implement IFPC feature. It doesn't support
>>>>>> any other features of a full fledged GMU like clock control, resource
>>>>>> voting to rpmh etc. So we need linux clock driver support like other
>>>>>> gmu-wrapper implementations to control gpu core clock and gpu GX gdsc.
>>>>>> This patch skips RGMU core initialization and act more like a
>>>>>> gmu-wrapper case.
>>>>>>
>>>>>> Co-developed-by: Akhil P Oommen <akhilpo@xxxxxxxxxxxxxxxx>
>>>>>> Signed-off-by: Jie Zhang <quic_jiezh@xxxxxxxxxxx>
>>>>>> Signed-off-by: Akhil P Oommen <akhilpo@xxxxxxxxxxxxxxxx>
>>>>>> ---
>>>>>
>>>>> [...]
>>>>>
>>>>>> @@ -350,12 +350,18 @@ static const struct a6xx_gmu_oob_bits a6xx_gmu_oob_bits[] = {
>>>>>>  /* Trigger a OOB (out of band) request to the GMU */
>>>>>>  int a6xx_gmu_set_oob(struct a6xx_gmu *gmu, enum a6xx_gmu_oob_state state)
>>>>>>  {
>>>>>> +   struct a6xx_gpu *a6xx_gpu = container_of(gmu, struct a6xx_gpu, gmu);
>>>>>> +   struct adreno_gpu *adreno_gpu = &a6xx_gpu->base;
>>>>>>     int ret;
>>>>>>     u32 val;
>>>>>>     int request, ack;
>>>>>>
>>>>>>     WARN_ON_ONCE(!mutex_is_locked(&gmu->lock));
>>>>>>
>>>>>> +   /* Skip OOB calls since RGMU is not enabled */
>>>>>
>>>>> "RGMU doesn't handle OOB calls"
>>>>
>>>> Technically RGMU can handle OOB calls. But we are not initializing rgmu.
>>>
>>> Oh, I glossed over that..
>>>
>>> IIRC the reason we delayed 612 support in the past was to make sure
>>> that the RGMU FW is consumed, so that runtime requirements don't
>>> suddenly change one day.
>>>
>>> If you have no interest/way in getting it wholly supported right now,
>>> can you at least make sure that the driver requests the firmware and
>>> exits if it's absent?
>>
>> adreno_load_gpu() calls adreno_load_fw() first thing, and will bail if
>> gmu fw is missing.  (zap fw is a bit more awkward since that could
>> come from dt or device table.)
> 
> Correct. And RGMU firmware is available in linux-firmware repo.

Thanks!

Konrad