drm/i915/dp: Make port sync mode assignments only if all tiles present

Add an extra check before making master slave assignments for tiled
displays to make sure we make these assignments only if all tiled
connectors are present. If not then initialize the state to defaults
so it does a normal non tiled modeset without transcoder port sync.

v4:
deafulat port sync values in prepare_cleared_state (Ville)
v3:
* Default master trans to INVALID to avoid pipe mismatch
v2:
* Rename icl_add_sync_mode_crtcs
* Move this function just before .compute_config hook
* Check if DP before master slave assignments (Ville)

Bugzilla: https://gitlab.freedesktop.org/drm/intel/issues/5
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191228031204.10189-2-manasi.d.navare@intel.com

drivers/gpu/drm/i915/display/intel_display.c

@@ -12260,88 +12260,121 @@ static bool c8_planes_changed(const struct intel_crtc_state *new_crtc_state)
 	return !old_crtc_state->c8_planes != !new_crtc_state->c8_planes;
 }
 
-static int icl_add_sync_mode_crtcs(struct intel_crtc_state *crtc_state)
+static bool
+intel_atomic_is_master_connector(struct intel_crtc_state *crtc_state)
+{
+	struct drm_crtc *crtc = crtc_state->uapi.crtc;
+	struct drm_atomic_state *state = crtc_state->uapi.state;
+	struct drm_connector *connector;
+	struct drm_connector_state *connector_state;
+	int i;
+
+	for_each_new_connector_in_state(state, connector, connector_state, i) {
+		if (connector_state->crtc != crtc)
+			continue;
+		if (connector->has_tile &&
+		    connector->tile_h_loc == connector->num_h_tile - 1 &&
+		    connector->tile_v_loc == connector->num_v_tile - 1)
+			return true;
+	}
+
+	return false;
+}
+
+static void reset_port_sync_mode_state(struct intel_crtc_state *crtc_state)
+{
+	crtc_state->master_transcoder = INVALID_TRANSCODER;
+	crtc_state->sync_mode_slaves_mask = 0;
+}
+
+static int icl_compute_port_sync_crtc_state(struct drm_connector *connector,
+					    struct intel_crtc_state *crtc_state,
+					    int num_tiled_conns)
 {
 	struct drm_crtc *crtc = crtc_state->uapi.crtc;
 	struct intel_atomic_state *state = to_intel_atomic_state(crtc_state->uapi.state);
 	struct drm_i915_private *dev_priv = to_i915(crtc_state->uapi.crtc->dev);
-	struct drm_connector *master_connector, *connector;
-	struct drm_connector_state *connector_state;
+	struct drm_connector *master_connector;
 	struct drm_connector_list_iter conn_iter;
 	struct drm_crtc *master_crtc = NULL;
 	struct drm_crtc_state *master_crtc_state;
 	struct intel_crtc_state *master_pipe_config;
-	int i, tile_group_id;
 
 	if (INTEL_GEN(dev_priv) < 11)
 		return 0;
 
+	if (!intel_crtc_has_type(crtc_state, INTEL_OUTPUT_DP))
+		return 0;
+
 	/*
 	 * In case of tiled displays there could be one or more slaves but there is
 	 * only one master. Lets make the CRTC used by the connector corresponding
 	 * to the last horizonal and last vertical tile a master/genlock CRTC.
 	 * All the other CRTCs corresponding to other tiles of the same Tile group
 	 * are the slave CRTCs and hold a pointer to their genlock CRTC.
+	 * If all tiles not present do not make master slave assignments.
 	 */
-	for_each_new_connector_in_state(&state->base, connector, connector_state, i) {
-		if (connector_state->crtc != crtc)
-			continue;
-		if (!connector->has_tile)
+	if (!connector->has_tile ||
+	    crtc_state->hw.mode.hdisplay != connector->tile_h_size ||
+	    crtc_state->hw.mode.vdisplay != connector->tile_v_size ||
+	    num_tiled_conns < connector->num_h_tile * connector->num_v_tile) {
+		reset_port_sync_mode_state(crtc_state);
+		return 0;
+	}
+	/* Last Horizontal and last vertical tile connector is a master
+	 * Master's crtc state is already populated in slave for port sync
+	 */
+	if (connector->tile_h_loc == connector->num_h_tile - 1 &&
+	    connector->tile_v_loc == connector->num_v_tile - 1)
+		return 0;
+
+	/* Loop through all connectors and configure the Slave crtc_state
+	 * to point to the correct master.
+	 */
+	drm_connector_list_iter_begin(&dev_priv->drm, &conn_iter);
+	drm_for_each_connector_iter(master_connector, &conn_iter) {
+		struct drm_connector_state *master_conn_state = NULL;
+
+		if (!(master_connector->has_tile &&
+		      master_connector->tile_group->id == connector->tile_group->id))
 			continue;
-		if (crtc_state->hw.mode.hdisplay != connector->tile_h_size ||
-		    crtc_state->hw.mode.vdisplay != connector->tile_v_size)
-			return 0;
-		if (connector->tile_h_loc == connector->num_h_tile - 1 &&
-		    connector->tile_v_loc == connector->num_v_tile - 1)
+		if (master_connector->tile_h_loc != master_connector->num_h_tile - 1 ||
+		    master_connector->tile_v_loc != master_connector->num_v_tile - 1)
 			continue;
-		crtc_state->sync_mode_slaves_mask = 0;
-		tile_group_id = connector->tile_group->id;
-		drm_connector_list_iter_begin(&dev_priv->drm, &conn_iter);
-		drm_for_each_connector_iter(master_connector, &conn_iter) {
-			struct drm_connector_state *master_conn_state = NULL;
 
-			if (!master_connector->has_tile)
-				continue;
-			if (master_connector->tile_h_loc != master_connector->num_h_tile - 1 ||
-			    master_connector->tile_v_loc != master_connector->num_v_tile - 1)
-				continue;
-			if (master_connector->tile_group->id != tile_group_id)
-				continue;
-
-			master_conn_state = drm_atomic_get_connector_state(&state->base,
-									   master_connector);
-			if (IS_ERR(master_conn_state)) {
-				drm_connector_list_iter_end(&conn_iter);
-				return PTR_ERR(master_conn_state);
-			}
-			if (master_conn_state->crtc) {
-				master_crtc = master_conn_state->crtc;
-				break;
-			}
+		master_conn_state = drm_atomic_get_connector_state(&state->base,
+								   master_connector);
+		if (IS_ERR(master_conn_state)) {
+			drm_connector_list_iter_end(&conn_iter);
+			return PTR_ERR(master_conn_state);
 		}
-		drm_connector_list_iter_end(&conn_iter);
-
-		if (!master_crtc) {
-			DRM_DEBUG_KMS("Could not find Master CRTC for Slave CRTC %d\n",
-				      connector_state->crtc->base.id);
-			return -EINVAL;
+		if (master_conn_state->crtc) {
+			master_crtc = master_conn_state->crtc;
+			break;
 		}
+	}
+	drm_connector_list_iter_end(&conn_iter);
 
-		master_crtc_state = drm_atomic_get_crtc_state(&state->base,
-							      master_crtc);
-		if (IS_ERR(master_crtc_state))
-			return PTR_ERR(master_crtc_state);
-
-		master_pipe_config = to_intel_crtc_state(master_crtc_state);
-		crtc_state->master_transcoder = master_pipe_config->cpu_transcoder;
-		master_pipe_config->sync_mode_slaves_mask |=
-			BIT(crtc_state->cpu_transcoder);
-		DRM_DEBUG_KMS("Master Transcoder = %s added for Slave CRTC = %d, slave transcoder bitmask = %d\n",
-			      transcoder_name(crtc_state->master_transcoder),
-			      crtc_state->uapi.crtc->base.id,
-			      master_pipe_config->sync_mode_slaves_mask);
+	if (!master_crtc) {
+		DRM_DEBUG_KMS("Could not find Master CRTC for Slave CRTC %d\n",
+			      crtc->base.id);
+		return -EINVAL;
 	}
 
+	master_crtc_state = drm_atomic_get_crtc_state(&state->base,
+						      master_crtc);
+	if (IS_ERR(master_crtc_state))
+		return PTR_ERR(master_crtc_state);
+
+	master_pipe_config = to_intel_crtc_state(master_crtc_state);
+	crtc_state->master_transcoder = master_pipe_config->cpu_transcoder;
+	master_pipe_config->sync_mode_slaves_mask |=
+		BIT(crtc_state->cpu_transcoder);
+	DRM_DEBUG_KMS("Master Transcoder = %s added for Slave CRTC = %d, slave transcoder bitmask = %d\n",
+		      transcoder_name(crtc_state->master_transcoder),
+		      crtc->base.id,
+		      master_pipe_config->sync_mode_slaves_mask);
+
 	return 0;
 }
 
@@ -12886,9 +12919,11 @@ intel_crtc_prepare_cleared_state(struct intel_crtc_state *crtc_state)
 		saved_state->wm = crtc_state->wm;
 	/*
 	 * Save the slave bitmask which gets filled for master crtc state during
-	 * slave atomic check call.
+	 * slave atomic check call. For all other CRTCs reset the port sync variables
+	 * crtc_state->master_transcoder needs to be set to INVALID
 	 */
-	if (is_trans_port_sync_master(crtc_state))
+	reset_port_sync_mode_state(saved_state);
+	if (intel_atomic_is_master_connector(crtc_state))
 		saved_state->sync_mode_slaves_mask =
 			crtc_state->sync_mode_slaves_mask;
 
@@ -12909,7 +12944,7 @@ intel_modeset_pipe_config(struct intel_crtc_state *pipe_config)
 	struct drm_connector *connector;
 	struct drm_connector_state *connector_state;
 	int base_bpp, ret;
-	int i;
+	int i, tile_group_id = -1, num_tiled_conns = 0;
 	bool retry = true;
 
 	pipe_config->cpu_transcoder =
@@ -12979,13 +13014,22 @@ intel_modeset_pipe_config(struct intel_crtc_state *pipe_config)
 	drm_mode_set_crtcinfo(&pipe_config->hw.adjusted_mode,
 			      CRTC_STEREO_DOUBLE);
 
-	/* Set the crtc_state defaults for trans_port_sync */
-	pipe_config->master_transcoder = INVALID_TRANSCODER;
-	ret = icl_add_sync_mode_crtcs(pipe_config);
-	if (ret) {
-		DRM_DEBUG_KMS("Cannot assign Sync Mode CRTCs: %d\n",
-			      ret);
-		return ret;
+	/* Get tile_group_id of tiled connector */
+	for_each_new_connector_in_state(state, connector, connector_state, i) {
+		if (connector_state->crtc == crtc &&
+		    connector->has_tile) {
+			tile_group_id = connector->tile_group->id;
+			break;
+		}
+	}
+
+	/* Get total number of tiled connectors in state that belong to
+	 * this tile group.
+	 */
+	for_each_new_connector_in_state(state, connector, connector_state, i) {
+		if (connector->has_tile &&
+		    connector->tile_group->id == tile_group_id)
+			num_tiled_conns++;
 	}
 
 	/* Pass our mode to the connectors and the CRTC to give them a chance to
@@ -12996,6 +13040,14 @@ intel_modeset_pipe_config(struct intel_crtc_state *pipe_config)
 		if (connector_state->crtc != crtc)
 			continue;
 
+		ret = icl_compute_port_sync_crtc_state(connector, pipe_config,
+						       num_tiled_conns);
+		if (ret) {
+			DRM_DEBUG_KMS("Cannot assign Sync Mode CRTCs: %d\n",
+				      ret);
+			return ret;
+		}
+
 		encoder = to_intel_encoder(connector_state->best_encoder);
 		ret = encoder->compute_config(encoder, pipe_config,
 					      connector_state);