Re: [PATCH 0/1] Fiji GPU audio register timeout when in BACO state

[Takashi Iwai <tiwai@suse.de>]

On Sat, 02 May 2020 09:27:31 +0200,
Takashi Iwai wrote:
> 
> On Sat, 02 May 2020 09:17:28 +0200,
> Lukas Wunner wrote:
> > 
> > On Sat, May 02, 2020 at 09:11:58AM +0200, Takashi Iwai wrote:
> > > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> > > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> > > @@ -673,6 +673,12 @@ static int amdgpu_dm_audio_component_bind(struct device *kdev,
> > >  	struct amdgpu_device *adev = dev->dev_private;
> > >  	struct drm_audio_component *acomp = data;
> > >  
> > > +	if (!device_link_add(hda_kdev, kdev, DL_FLAG_STATELESS |
> > > +			     DL_FLAG_PM_RUNTIME)) {
> > > +		DRM_ERROR("DM: cannot add device link to audio device\n");
> > > +		return -ENOMEM;
> > > +	}
> > > +
> > 
> > Doesn't this duplicate drivers/pci/quirks.c:quirk_gpu_hda() ?
> 
> Gah, you're right, that was the place I overlooked.
> It was a typical "false Eureka right-after-wakeup" phenomenon :)
> Need a vaccine aka coffee...
> 
> So the runtime PM dependency must be already placed there, and the
> problem is not the lack of the dependency tree but the really other
> timing issue.  Back to square.

One interesting test is to open the stream while the mode isn't set
yet and see whether the same problem appears.
Namely, after the monitor is connected but no mode is set, run
directly like
   aplay -Dhdmi:1,0 foo.wav
You might need to wrap the command with pasuspender if PA is active.


Takashi