[Intel-gfx] [PATCH] drm/i915: Fix frontbuffer false positve.

[Daniel Vetter]

On Mon, Feb 02, 2015 at 03:38:16PM -0800, Rodrigo Vivi wrote:
> frontbuffer bits must be updated during commit times not on atomica prepare
> one, otherwise we have a risk of false positive.
>
> Cc Daniel Vetter <daniel.vetter at ffwll.ch>
> Cc: Sonika Jindal <sonika.jindal at intel.com>
> Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>

atomic.fb_bits isn't used at all right now, instead the begin_crtc_commit
function recomputes them. That looks wrong. Also for async commits we need
to do the proper 2-stage flip stuff that current page_flip code does using
frontbuffer_flip_prepare/complete.

This patch here should have 0 effect (presuming I'm reading code
correctly), so what kinf of bug exactly are you seeing?

Adding Matt&Ander.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch