Hibernation broken since commit 274ad65c9d02 ("drm/radeon: hard reset r600 and newer GPU when hibernating.")

[Jerome Glisse]

> Recently I got myself a new laptop with the following integrated GPU:
> 
> 00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI]
> Mullins [Radeon R3 Graphics] (rev 40)
> 
> I found that hibernation is broken in Linux 4.7+ (it works in Linux 4.6)
> and bisected it to commit 274ad65c9d02 ("drm/radeon: hard reset r600 and
> newer GPU when hibernating.").
> 
> This has already been reported three months ago, but for a much older
> GPU, see the thread starting at
> https://lists.freedesktop.org/archives/dri-devel/2016-June/110050.html.
> The symptoms are exactly the same as described by Boris Petkov in that
> thread: after "systemctl hibernate" the screen goes blank, but the
> machine remains powered on and needs to be power-cycled.
> 
> Any suggestions would be welcome.
> 
> Cheers,
>        Sven

I guess we can invert the logic and only do it for the GPU for which it fix
hibernation.

Cheers,
Jérôme