drm/i915: implement fastpath for overlay flip waiting

As long as the gpu can keep up, neither the cpu (waiting for gpu)
nore the gpu (waiting for vblank to do an overlay flip) stalls.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index c9b1b97ab792..5b503cb793ba 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -126,7 +126,9 @@ struct intel_overlay {
         u32 flip_addr;
         struct drm_i915_gem_object *reg_bo;
         void *virt_addr;
+        /* flip handling */
         int hw_wedged;
+        uint32_t last_flip_req;
 };
 
 struct intel_crtc {