[Intel-gfx] [PATCH 3/3] drm/i915: remove the vblank_wait hack from HSW+

[Daniel Vetter]

On Thu, Dec 19, 2013 at 10:12 PM, Paulo Zanoni <przanoni at gmail.com> wrote:
> From: Paulo Zanoni <paulo.r.zanoni at intel.com>
>
> When I forked haswell_crtc_enable I copied all the code from
> ironlake_crtc_enable. The last piece of the function contains a big
> comment with a call to intel_wait_for_vblank. After this fork, we
> rearranged the Haswell code so that it enables the planes as the very
> last step of the modeset sequence, so we're sure that we call
> intel_enable_primary_plane after the pipe is really running, so the
> vblank waiting functions work as expected. I really believe this is
> what fixes the problem described by the big comment, so let's give it
> a try and get rid of that intel_wait_for_vblank, saving around 16ms
> per modeset (and init/resume). We can always revert if needed :)
>
> Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>

If kms_flip doesn't start failing you're good. Iirc I've added some
flip vs. modeset and flip vs. dpms tests specifically for this.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch