[PATCH xf86-video-amdgpu] Store FB for each CRTC in drmmode_flipdata_rec

[Johannes Hirte]

On 2018 Jul 27, Michel Dänzer wrote:
> From: Michel Dänzer <michel.daenzer at amd.com>
> 
> We were only storing the FB provided by the client, but on CRTCs with
> TearFree enabled, we use a separate FB. This could cause
> drmmode_flip_handler to fail to clear drmmode_crtc->flip_pending, which
> could result in a hang when waiting for the pending flip to complete. We
> were trying to avoid that by always clearing drmmode_crtc->flip_pending
> when TearFree is enabled, but that wasn't reliable, because
> drmmode_crtc->tear_free can already be FALSE at this point when
> disabling TearFree.
> 
> Now that we're keeping track of each CRTC's flip FB separately,
> drmmode_flip_handler can reliably clear flip_pending, and we no longer
> need the TearFree hack.
> 
> Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>

Since this change I get a black screen when login into KDE Plasma. I
have to switch to linux console and back for getting the X11 screen.
Additional the Xorg.log is spammed with:

[   189.744] (WW) AMDGPU(0): get vblank counter failed: Invalid argument
[   189.828] (WW) AMDGPU(0): flip queue failed in amdgpu_scanout_flip: Device or resource busy, TearFree inactive until next modeset
[   189.828] (WW) AMDGPU(0): drmmode_wait_vblank failed for scanout update: Invalid argument
[   189.828] (WW) AMDGPU(0): drmmode_wait_vblank failed for scanout update: Invalid argument

The "flip queue failed" message appears only once, the other two are
much more often.

System is a Carrizo A10-8700B, kernel 4.17.13 + this patch:
https://bugzilla.kernel.org/attachment.cgi?id=276173


-- 
Regards,
  Johannes