drm/amd/display: Ensure valid event timestamp for cursor-only commits

Requires enabling the vblank machinery for them.

Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/2030
Signed-off-by: Michel Dänzer <mdaenzer@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

Author: Michel Dänzer

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -463,6 +463,26 @@ static void dm_pflip_high_irq(void *interrupt_params)
 		     vrr_active, (int) !e);
 }
 
+static void dm_crtc_handle_vblank(struct amdgpu_crtc *acrtc)
+{
+	struct drm_crtc *crtc = &acrtc->base;
+	struct drm_device *dev = crtc->dev;
+	unsigned long flags;
+
+	drm_crtc_handle_vblank(crtc);
+
+	spin_lock_irqsave(&dev->event_lock, flags);
+
+	/* Send completion event for cursor-only commits */
+	if (acrtc->event && acrtc->pflip_status != AMDGPU_FLIP_SUBMITTED) {
+		drm_crtc_send_vblank_event(crtc, acrtc->event);
+		drm_crtc_vblank_put(crtc);
+		acrtc->event = NULL;
+	}
+
+	spin_unlock_irqrestore(&dev->event_lock, flags);
+}
+
 static void dm_vupdate_high_irq(void *interrupt_params)
 {
 	struct common_irq_params *irq_params = interrupt_params;
@@ -501,7 +521,7 @@ static void dm_vupdate_high_irq(void *interrupt_params)
 		 * if a pageflip happened inside front-porch.
 		 */
 		if (vrr_active) {
-			drm_crtc_handle_vblank(&acrtc->base);
+			dm_crtc_handle_vblank(acrtc);
 
 			/* BTR processing for pre-DCE12 ASICs */
 			if (acrtc->dm_irq_params.stream &&
@@ -553,7 +573,7 @@ static void dm_crtc_high_irq(void *interrupt_params)
 	 * to dm_vupdate_high_irq after end of front-porch.
 	 */
 	if (!vrr_active)
-		drm_crtc_handle_vblank(&acrtc->base);
+		dm_crtc_handle_vblank(acrtc);
 
 	/**
 	 * Following stuff must happen at start of vblank, for crc
@@ -9174,6 +9194,7 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
 	struct amdgpu_bo *abo;
 	uint32_t target_vblank, last_flip_vblank;
 	bool vrr_active = amdgpu_dm_vrr_active(acrtc_state);
+	bool cursor_update = false;
 	bool pflip_present = false;
 	struct {
 		struct dc_surface_update surface_updates[MAX_SURFACES];
@@ -9209,8 +9230,13 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
 		struct dm_plane_state *dm_new_plane_state = to_dm_plane_state(new_plane_state);
 
 		/* Cursor plane is handled after stream updates */
-		if (plane->type == DRM_PLANE_TYPE_CURSOR)
+		if (plane->type == DRM_PLANE_TYPE_CURSOR) {
+			if ((fb && crtc == pcrtc) ||
+			    (old_plane_state->fb && old_plane_state->crtc == pcrtc))
+				cursor_update = true;
+
 			continue;
+		}
 
 		if (!fb || !crtc || pcrtc != crtc)
 			continue;
@@ -9373,6 +9399,17 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
 				bundle->stream_update.vrr_infopacket =
 					&acrtc_state->stream->vrr_infopacket;
 		}
+	} else if (cursor_update && acrtc_state->active_planes > 0 &&
+		   !acrtc_state->force_dpms_off &&
+		   acrtc_attach->base.state->event) {
+		drm_crtc_vblank_get(pcrtc);
+
+		spin_lock_irqsave(&pcrtc->dev->event_lock, flags);
+
+		acrtc_attach->event = acrtc_attach->base.state->event;
+		acrtc_attach->base.state->event = NULL;
+
+		spin_unlock_irqrestore(&pcrtc->dev->event_lock, flags);
 	}
 
 	/* Update the planes if changed or disable if we don't have any. */