[Intel-gfx] [PATCH 3/5] drm/i915: Fix gen3/4 vblank counter wraparound

[Daniel Vetter]

On Thu, Nov 07, 2013 at 06:16:47PM +0200, Imre Deak wrote:
> On Wed, 2013-11-06 at 13:56 -0200, Rodrigo Vivi wrote:
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > 
> > When the hardware frame counter reads 0xffffff and we're already past
> > vblank start, we'd return 0x1000000 as the vblank counter value. Once
> > we'd cross into the next frame's active portion, the vblank counter
> > would wrap to 0. So we're reporting two different vblank counter values
> > for the same frame.
> > 
> > Fix the problem by masking the cooked value by 0xffffff to make sure
> > the counter wraps already after vblank start.
> > 
> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Signed-off-by: Rodrigo Vivi <rodrigo.vivi at gmail.com>
> 
> Reviewed-by: Imre Deak <imre.deak at intel.com>

Queued for -next, thanks for the patch.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch