[PATCH] drm/amd/display: ensure async flips are only accepted for fast updates

[Hamza Mahfooz]

We should be checking to see if async flips are supported in
amdgpu_dm_atomic_check() (i.e. not dm_crtc_helper_atomic_check()). Also,
async flipping isn't supported if a plane's framebuffer changes memory
domains during an atomic commit. So, move the check from
dm_crtc_helper_atomic_check() to amdgpu_dm_atomic_check() and check if
the memory domain has changed in amdgpu_dm_atomic_check().

Cc: stable at vger.kernel.org
Fixes: 3f86b60691e6 ("drm/amd/display: only accept async flips for fast updates")
Tested-by: Marcus Seyfarth <m.seyfarth at gmail.com>
Signed-off-by: Hamza Mahfooz <hamza.mahfooz at amd.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 25 ++++++++++++++++---
 .../amd/display/amdgpu_dm/amdgpu_dm_crtc.c    | 12 ---------
 2 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 32fb551862b0..e561d99b3f40 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -8086,7 +8086,8 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
 		 * fast updates.
 		 */
 		if (crtc->state->async_flip &&
-		    acrtc_state->update_type != UPDATE_TYPE_FAST)
+		    (acrtc_state->update_type != UPDATE_TYPE_FAST ||
+		     get_mem_type(old_plane_state->fb) != get_mem_type(fb)))
 			drm_warn_once(state->dev,
 				      "[PLANE:%d:%s] async flip with non-fast update\n",
 				      plane->base.id, plane->name);
@@ -10050,12 +10051,18 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 
 	/* Remove exiting planes if they are modified */
 	for_each_oldnew_plane_in_state_reverse(state, plane, old_plane_state, new_plane_state, i) {
+		if (old_plane_state->fb && new_plane_state->fb &&
+		    get_mem_type(old_plane_state->fb) !=
+		    get_mem_type(new_plane_state->fb))
+			lock_and_validation_needed = true;
+
 		ret = dm_update_plane_state(dc, state, plane,
 					    old_plane_state,
 					    new_plane_state,
 					    false,
 					    &lock_and_validation_needed,
 					    &is_top_most_overlay);
+
 		if (ret) {
 			DRM_DEBUG_DRIVER("dm_update_plane_state() failed\n");
 			goto fail;
@@ -10069,6 +10076,7 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 					   new_crtc_state,
 					   false,
 					   &lock_and_validation_needed);
+
 		if (ret) {
 			DRM_DEBUG_DRIVER("DISABLE: dm_update_crtc_state() failed\n");
 			goto fail;
@@ -10297,9 +10305,18 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
 		struct dm_crtc_state *dm_new_crtc_state =
 			to_dm_crtc_state(new_crtc_state);
 
-		dm_new_crtc_state->update_type = lock_and_validation_needed ?
-							 UPDATE_TYPE_FULL :
-							 UPDATE_TYPE_FAST;
+		/*
+		 * Only allow async flips for fast updates that don't change
+		 * the FB pitch, the DCC state, rotation, etc.
+		 */
+		if (new_crtc_state->async_flip && lock_and_validation_needed) {
+			drm_dbg_atomic(crtc->dev,
+				       "[CRTC:%d:%s] async flips are only supported for fast updates\n",
+				       crtc->base.id, crtc->name);
+			ret = -EINVAL;
+			goto fail;
+		} else
+			dm_new_crtc_state->update_type = UPDATE_TYPE_FAST;
 	}
 
 	/* Must be success */
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
index 30d4c6fd95f5..440fc0869a34 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
@@ -398,18 +398,6 @@ static int dm_crtc_helper_atomic_check(struct drm_crtc *crtc,
 		return -EINVAL;
 	}
 
-	/*
-	 * Only allow async flips for fast updates that don't change the FB
-	 * pitch, the DCC state, rotation, etc.
-	 */
-	if (crtc_state->async_flip &&
-	    dm_crtc_state->update_type != UPDATE_TYPE_FAST) {
-		drm_dbg_atomic(crtc->dev,
-			       "[CRTC:%d:%s] async flips are only supported for fast updates\n",
-			       crtc->base.id, crtc->name);
-		return -EINVAL;
-	}
-
 	/* In some use cases, like reset, no stream is attached */
 	if (!dm_crtc_state->stream)
 		return 0;
-- 
2.41.0