tree c2e594cd97cdf6c656285e789639c0caf07699c4
parent 26e1fe4fbd4c15919f8cfa9440d70eca5a457ba3
author Ville Syrjälä <ville.syrjala@linux.intel.com> 1435172407 +0300
committer Daniel Vetter <daniel.vetter@ffwll.ch> 1435568287 +0200

drm/i915: Try to make sure cxsr is disabled around plane enable/disable

CxSR (or maxfifo on VLV/CHV) blocks somne changes to the plane control
register (enable bit at least, not quite sure about the rest). So in
order to have the plane enable/disable when we want we need to first
kick the hardware out of cxsr.

Unfortunateloy this requires some extra vblank waits. For the CxSR
enable after the plane update we should eventually use an async
vblank worker, but since we don't have that just do sync vblank
waits. For the disable case we have no choice but to do it
synchronously.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Clint Taylor <Clinton.A.Taylor@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>