[PATCH 2/2] drm/amdgpu: allow APU to send power gate message when dpm is disabled

[Lazar, Lijo]

On 12/6/2021 12:18 PM, Yu, Lang wrote:
> [Public]
> 
> A typo.
> 
>> -----Original Message-----
>> From: Yu, Lang
>> Sent: Monday, December 6, 2021 2:47 PM
>> To: Lazar, Lijo <Lijo.Lazar at amd.com>; amd-gfx at lists.freedesktop.org
>> Cc: Deucher, Alexander <Alexander.Deucher at amd.com>; Huang, Ray
>> <Ray.Huang at amd.com>
>> Subject: RE: [PATCH 2/2] drm/amdgpu: allow APU to send power gate message
>> when dpm is disabled
>>
>> [Public]
>>
>>
>>
>>> -----Original Message-----
>>> From: Lazar, Lijo <Lijo.Lazar at amd.com>
>>> Sent: Monday, December 6, 2021 11:41 AM
>>> To: Yu, Lang <Lang.Yu at amd.com>; amd-gfx at lists.freedesktop.org
>>> Cc: Deucher, Alexander <Alexander.Deucher at amd.com>; Huang, Ray
>>> <Ray.Huang at amd.com>
>>> Subject: Re: [PATCH 2/2] drm/amdgpu: allow APU to send power gate
>>> message when dpm is disabled
>>>
>>>
>>>
>>> On 12/6/2021 8:19 AM, Yu, Lang wrote:
>>>> [Public]
>>>>
>>>>
>>>>
>>>>> -----Original Message-----
>>>>> From: Lazar, Lijo <Lijo.Lazar at amd.com>
>>>>> Sent: Friday, December 3, 2021 5:52 PM
>>>>> To: Yu, Lang <Lang.Yu at amd.com>; amd-gfx at lists.freedesktop.org
>>>>> Cc: Deucher, Alexander <Alexander.Deucher at amd.com>; Huang, Ray
>>>>> <Ray.Huang at amd.com>
>>>>> Subject: Re: [PATCH 2/2] drm/amdgpu: allow APU to send power gate
>>>>> message when dpm is disabled
>>>>>
>>>>>
>>>>>
>>>>> On 12/3/2021 12:24 PM, Lang Yu wrote:
>>>>>> The general hw fini sequence is SMU-> ... ->SDMA-> ...
>>>>>> We need to send power gate message to power off SDMA(in SDMA
>>>>>> hw_fini()) afer dpm is disabled(in SMU hw_fini()). Allow that for APU.
>>>>>
>>>>> This message is not right. In APUs there is no message provided by
>>>>> FW to enable/disable DPM, it is done in BIOS. Rephrase to something
>>>>> like after smu hw_fini is completed.
>>>>
>>>> It is power on/off SDMA message. Not enable/disable DPM.
>>>>
>>> Bad choice of word :) I didn't mean FW message, it was about this line
>>> in "commit message" - "afer dpm is disabled".
>>
>> Ok. I got it.
>>
>>>
>>>>>>
>>>>>> Signed-off-by: Lang Yu <lang.yu at amd.com>
>>>>>> ---
>>>>>>     drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c | 2 +-
>>>>>>     1 file changed, 1 insertion(+), 1 deletion(-)
>>>>>>
>>>>>> diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
>>>>>> b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
>>>>>> index 2d718c30c8eb..285a237f3605 100644
>>>>>> --- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
>>>>>> +++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
>>>>>> @@ -277,7 +277,7 @@ static int smu_dpm_set_power_gate(void *handle,
>>>>>>     	struct smu_context *smu = handle;
>>>>>>     	int ret = 0;
>>>>>>
>>>>>> -	if (!smu->pm_enabled || !smu->adev->pm.dpm_enabled) {
>>>>>> +	if (!smu->pm_enabled || (!smu->is_apu &&
>>>>>> +!smu->adev->pm.dpm_enabled)) {
>>>>>
>>>>>
>>>>> This check was there before also, only the WARN is added. That means
>>>>> it was skipping sending messages in APUs also and so far this was
>>>>> working fine (until this gets noticed because of the warning).
>>>>>
>>>>> Now this would try to send the message to APU without any check.
>>>>> That doesn't look good. Ideal way should be to fix the sequence.
>>>>> Otherwise, suggest to do something like below as the last step of
>>>>> smu hw cleanup rather than sending the message blindly.
>>>>>
>>>>> 	if (smu->is_apu)
>>>>> 		smu->pm.dpm_enabled = smu_is_dpm_running(smu);
>>>>
>>>> smu_is_dpm_running(smu) will cause errors in suspend.
>>>>
>>> That is interesting. What is the error you get?
>>
>> [drm:amdgpu_dpm_enable_uvd [amdgpu]] *ERROR* Dpm enable uvd failed, ret =
>> -95 That means EOPNOTSUPP.
>>
>> Actually, in resume process, but adev->in_suspend  is still true.
>> For Renoir series APU, smu_is_dpm_running is hardcoded as following,
>>
>> static bool renoir_is_dpm_running(struct smu_context *smu) {
>> 	struct amdgpu_device *adev = smu->adev;
>>
>> 	/*
>> 	 * Until now, the pmfw hasn't exported the interface of SMU
>> 	 * feature mask to APU SKU so just force on all the feature
>> 	 * at early initial stage.
>> 	 */
>> 	if (adev->in_suspend)
>> 		return false;
>> 	else

Renoir suspend shouldn't be a special case. FW should keep running with 
features enabled after driver suspend. Could you try with a return true 
all the time for this?

Thanks,
Lijo

>> 		return true;
>>
>> }
>>
>> So we got such an error.
>>
>> Regards,
>> Lang
>>
>>> Thanks,
>>> Lijo
>>>
>>>> Here we just  send some IP power on/off messages.
>>>> Is it necessary to enable DPM to send such messages?
>>>>
>>>> Regards,
>>>> Lang
>>>>
>>>>> Thanks,
>>>>> Lijo
>>>>>
>>>>>>     		dev_WARN(smu->adev->dev,
>>>>>>     			 "SMU uninitialized but power %s requested for %u!\n",
>>>>>>     			 gate ? "gate" : "ungate", block_type);
>>>>>>