From: Rob Clark <robdcl...@chromium.org>

For an atomic commit updating a single CRTC (ie. a pageflip) calculate
the next vblank time, and inform the fence(s) of that deadline.

v2: Comment typo fix (danvet)

Signed-off-by: Rob Clark <robdcl...@chromium.org>
Reviewed-by: Daniel Vetter <daniel.vet...@ffwll.ch>
Signed-off-by: Rob Clark <robdcl...@chromium.org>
---
 drivers/gpu/drm/drm_atomic_helper.c | 36 +++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c 
b/drivers/gpu/drm/drm_atomic_helper.c
index d579fd8f7cb8..d8ee98ce2fc5 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1511,6 +1511,40 @@ void drm_atomic_helper_commit_modeset_enables(struct 
drm_device *dev,
 }
 EXPORT_SYMBOL(drm_atomic_helper_commit_modeset_enables);
 
+/*
+ * For atomic updates which touch just a single CRTC, calculate the time of the
+ * next vblank, and inform all the fences of the deadline.
+ */
+static void set_fence_deadline(struct drm_device *dev,
+                              struct drm_atomic_state *state)
+{
+       struct drm_crtc *crtc, *wait_crtc = NULL;
+       struct drm_crtc_state *new_crtc_state;
+       struct drm_plane *plane;
+       struct drm_plane_state *new_plane_state;
+       ktime_t vbltime;
+       int i;
+
+       for_each_new_crtc_in_state (state, crtc, new_crtc_state, i) {
+               if (wait_crtc)
+                       return;
+               wait_crtc = crtc;
+       }
+
+       /* If no CRTCs updated, then nothing to do: */
+       if (!wait_crtc)
+               return;
+
+       if (drm_crtc_next_vblank_start(wait_crtc, &vbltime))
+               return;
+
+       for_each_new_plane_in_state (state, plane, new_plane_state, i) {
+               if (!new_plane_state->fence)
+                       continue;
+               dma_fence_set_deadline(new_plane_state->fence, vbltime);
+       }
+}
+
 /**
  * drm_atomic_helper_wait_for_fences - wait for fences stashed in plane state
  * @dev: DRM device
@@ -1540,6 +1574,8 @@ int drm_atomic_helper_wait_for_fences(struct drm_device 
*dev,
        struct drm_plane_state *new_plane_state;
        int i, ret;
 
+       set_fence_deadline(dev, state);
+
        for_each_new_plane_in_state(state, plane, new_plane_state, i) {
                if (!new_plane_state->fence)
                        continue;
-- 
2.39.1

Reply via email to