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

From: Deucher, Alexander
Date: Mon Apr 27 2020 - 10:22:27 EST


[AMD Public Use]

> -----Original Message-----
> From: Nicholas Johnson <nicholas.johnson-opensource@xxxxxxxxxxxxxx>
> Sent: Sunday, April 26, 2020 12:02 PM
> To: linux-kernel@xxxxxxxxxxxxxxx
> Cc: Deucher, Alexander <Alexander.Deucher@xxxxxxx>; Koenig, Christian
> <Christian.Koenig@xxxxxxx>; Zhou, David(ChunMing)
> <David1.Zhou@xxxxxxx>; Nicholas Johnson <nicholas.johnson-
> opensource@xxxxxxxxxxxxxx>
> 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.

Alex