[Freedreno] [PATCH] drm: msm: a6xx: fix gpu failure after system resume

[Rob Clark]

On Tue, Jul 14, 2020 at 10:10 AM Matthias Kaehlcke <mka at chromium.org> wrote:
>
> On Tue, Jul 14, 2020 at 06:55:30PM +0530, Akhil P Oommen wrote:
> > On targets where GMU is available, GMU takes over the ownership of GX GDSC
> > during its initialization. So, take a refcount on the GX PD on behalf of
> > GMU before we initialize it. This makes sure that nobody can collapse the
> > GX GDSC once GMU owns the GX GDSC. This patch fixes some weird failures
> > during GPU wake up during system resume.
> >
> > Signed-off-by: Akhil P Oommen <akhilpo at codeaurora.org>
>
> I went through a few dozen suspend/resume cycles on SC7180 and didn't run
> into the kernel panic that typically occurs after a few iterations without
> this patch.
>
> Reported-by: Matthias Kaehlcke <mka at chromium.org>
> Tested-by: Matthias Kaehlcke <mka at chromium.org>
>
> On which tree is this patch based on? I had to apply it manually because
> 'git am' is unhappy when I try to apply it:
>
>   error: sha1 information is lacking or useless (drivers/gpu/drm/msm/adreno/a6xx_gmu.c).
>   error: could not build fake ancestor
>
> Both upstream and drm-msm are in my remotes and synced, so I suspect it's
> some private tree. Please make sure to base patches on the corresponding
> maintainer tree or upstream, whichs makes life easier for maintainers,
> testers and reviewers.

I've run into the same issue frequently :-(

BR,
-R