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

[Takashi Iwai <tiwai@suse.de>]

On Mon, 27 Apr 2020 16:22:21 +0200,
Deucher, Alexander wrote:
> 
> [AMD Public Use]
> 
> > -----Original Message-----
> > From: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
> > Sent: Sunday, April 26, 2020 12:02 PM
> > To: linux-kernel@vger.kernel.org
> > Cc: Deucher, Alexander <Alexander.Deucher@amd.com>; Koenig, Christian
> > <Christian.Koenig@amd.com>; Zhou, David(ChunMing)
> > <David1.Zhou@amd.com>; Nicholas Johnson <nicholas.johnson-
> > opensource@outlook.com.au>
> > Subject: [PATCH 0/1] Fiji GPU audio register timeout when in BACO state
> > 
> > Hi all,
> > 
> > Since Linux v5.7-rc1 / commit 4fdda2e66de0 ("drm/amdgpu/runpm: enable
> > runpm on baco capable VI+ asics"), my AMD R9 Nano has been using runpm /
> > BACO. You can tell visually when it sleeps, because the fan on the graphics
> > card is switched off to save power. It did not spin down the fan in v5.6.x.
> > 
> > This is great (I love it), except that when it is sleeping, the PCIe audio function
> > of the GPU has issues if anything tries to access it. You get dmesg errors such
> > as these:
> > 
> > snd_hda_intel 0000:08:00.1: spurious response 0x0:0x0, last cmd=0x170500
> > snd_hda_intel 0000:08:00.1: azx_get_response timeout, switching to polling
> > mode: last cmd=0x001f0500 snd_hda_intel 0000:08:00.1: No response from
> > codec, disabling MSI: last cmd=0x001f0500 snd_hda_intel 0000:08:00.1: No
> > response from codec, resetting bus: last cmd=0x001f0500
> > snd_hda_codec_hdmi hdaudioC1D0: Unable to sync register 0x2f0d00. -11
> > 
> > The above is with the Fiji XT GPU at 0000:08:00.0 in a Thunderbolt enclosure
> > (not that Thunderbolt should affect it, but I feel I should mention it just in
> > case). I dropped a lot of duplicate dmesg lines, as some of them repeated a
> > lot of times before the driver gave up.
> > 
> > I offer this patch to disable runpm for Fiji while a fix is found, if you decide
> > that is the best approach. Regardless, I will gladly test any patches you come
> > up with instead and confirm that the above issue has been fixed.
> > 
> > I cannot tell if any other GPUs are affected. The only other cards to which I
> > have access are a couple of AMD R9 280X (Tahiti XT), which use radeon driver
> > instead of amdgpu driver.
> 
> Adding a few more people.  Do you know what is accessing the audio?  The audio should have a dependency on the GPU device.  The GPU won't enter runtime pm until the audio has entered runtime pm and vice versa on resume. Please attach a copy of your dmesg output and lspci output.

Also, please retest with the fresh 5.7-rc3.  There was a known
regression regarding HD-audio PM in 5.7-rc1/rc2, and it's been fixed
there (commit 8d6762af302d).


thanks,

Takashi