drm/i915/dp: Make sure all tiled connectors get added to the state wi…

…th full modeset

In case of tiled displays, all the tiles are linke dto each other
for transcoder port sync. So in intel_atomic_check() we need to make
sure that we add all the tiles to the modeset and if one of the
tiles needs a full modeset then mark all other tiles for a full modeset.

We also need to force modeset for all synced crtcs after fastset check.

v6:
* Add comments about why we do not call
drm_atomic_helper_check_modeset (Matt)
* Add FIXME for a corner case where tile info might vanish (Matt)
v5:
* Rebase
v4:
* Fix logic for modeset_synced_crtcs (Ville)
v3:
* Add tile checks only for Gen >11
v2:
* Change crtc_state scope, remove tile_grp_id (Ville)
* Use intel_connector_needs_modeset() (Ville)
* Add modeset_synced_crtcs (Ville)
* Make sure synced crtcs are forced full modeset
after fastset check (Ville)

Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Bugzilla: https://gitlab.freedesktop.org/drm/intel/issues/5
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191228031204.10189-1-manasi.d.navare@intel.com

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

@@ -14301,6 +14301,118 @@ static bool intel_cpu_transcoder_needs_modeset(struct intel_atomic_state *state,
 	return false;
 }
 
+static void
+intel_modeset_synced_crtcs(struct intel_atomic_state *state,
+			   u8 transcoders)
+{
+	struct intel_crtc_state *new_crtc_state;
+	struct intel_crtc *crtc;
+	int i;
+
+	for_each_new_intel_crtc_in_state(state, crtc,
+					 new_crtc_state, i) {
+		if (transcoders & BIT(new_crtc_state->cpu_transcoder)) {
+			new_crtc_state->uapi.mode_changed = true;
+			new_crtc_state->update_pipe = false;
+		}
+	}
+}
+
+static void
+intel_atomic_check_synced_crtcs(struct intel_atomic_state *state)
+{
+	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
+	struct intel_crtc_state *new_crtc_state;
+	struct intel_crtc *crtc;
+	int i;
+
+	if (INTEL_GEN(dev_priv) < 11)
+		return;
+
+	for_each_new_intel_crtc_in_state(state, crtc,
+					 new_crtc_state, i) {
+		if (is_trans_port_sync_master(new_crtc_state) &&
+		    needs_modeset(new_crtc_state)) {
+			intel_modeset_synced_crtcs(state,
+						   new_crtc_state->sync_mode_slaves_mask);
+		} else if (is_trans_port_sync_slave(new_crtc_state) &&
+			   needs_modeset(new_crtc_state)) {
+			intel_modeset_synced_crtcs(state,
+						   BIT(new_crtc_state->master_transcoder));
+		}
+	}
+}
+
+static int
+intel_modeset_all_tiles(struct intel_atomic_state *state, int tile_grp_id)
+{
+	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
+	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
+	int ret = 0;
+
+	drm_connector_list_iter_begin(&dev_priv->drm, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
+		struct drm_connector_state *conn_state;
+		struct drm_crtc_state *crtc_state;
+
+		if (!connector->has_tile ||
+		    connector->tile_group->id != tile_grp_id)
+			continue;
+		conn_state = drm_atomic_get_connector_state(&state->base,
+							    connector);
+		if (IS_ERR(conn_state)) {
+			ret =  PTR_ERR(conn_state);
+			break;
+		}
+
+		if (!conn_state->crtc)
+			continue;
+
+		crtc_state = drm_atomic_get_crtc_state(&state->base,
+						       conn_state->crtc);
+		if (IS_ERR(crtc_state)) {
+			ret = PTR_ERR(conn_state);
+			break;
+		}
+		crtc_state->mode_changed = true;
+		ret = drm_atomic_add_affected_connectors(&state->base,
+							 conn_state->crtc);
+		if (ret)
+			break;
+	}
+	drm_connector_list_iter_end(&conn_iter);
+
+	return ret;
+}
+
+static int
+intel_atomic_check_tiled_conns(struct intel_atomic_state *state)
+{
+	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
+	struct drm_connector *connector;
+	struct drm_connector_state *old_conn_state, *new_conn_state;
+	int i, ret;
+
+	if (INTEL_GEN(dev_priv) < 11)
+		return 0;
+
+	/* Is tiled, mark all other tiled CRTCs as needing a modeset */
+	for_each_oldnew_connector_in_state(&state->base, connector,
+					   old_conn_state, new_conn_state, i) {
+		if (!connector->has_tile)
+			continue;
+		if (!intel_connector_needs_modeset(state, connector))
+			continue;
+
+		ret = intel_modeset_all_tiles(state, connector->tile_group->id);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 /**
  * intel_atomic_check - validate state object
  * @dev: drm device
@@ -14328,6 +14440,21 @@ static int intel_atomic_check(struct drm_device *dev,
 	if (ret)
 		goto fail;
 
+	/**
+	 * This check adds all the connectors in current state that belong to
+	 * the same tile group to a full modeset.
+	 * This function directly sets the mode_changed to true and we also call
+	 * drm_atomic_add_affected_connectors(). Hence we are not explicitly
+	 * calling drm_atomic_helper_check_modeset() after this.
+	 *
+	 * Fixme: Handle some corner cases where one of the
+	 * tiled connectors gets disconnected and tile info is lost but since it
+	 * was previously synced to other conn, we need to add that to the modeset.
+	 */
+	ret = intel_atomic_check_tiled_conns(state);
+	if (ret)
+		goto fail;
+
 	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
 					    new_crtc_state, i) {
 		if (!needs_modeset(new_crtc_state)) {
@@ -14375,6 +14502,17 @@ static int intel_atomic_check(struct drm_device *dev,
 		}
 	}
 
+	/**
+	 * In case of port synced crtcs, if one of the synced crtcs
+	 * needs a full modeset, all other synced crtcs should be
+	 * forced a full modeset. This checks if fastset is allowed
+	 * by other dependencies like the synced crtcs.
+	 * Here we set the mode_changed to true directly to force full
+	 * modeset hence we do not explicitly call the function
+	 * drm_atomic_helper_check_modeset().
+	 */
+	intel_atomic_check_synced_crtcs(state);
+
 	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
 					    new_crtc_state, i) {
 		if (needs_modeset(new_crtc_state)) {