diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
index 3cacb1e279c1..be5bc506d4d3 100644
--- a/drivers/gpu/drm/i915/display/intel_ddi.c
+++ b/drivers/gpu/drm/i915/display/intel_ddi.c
@@ -1903,8 +1903,13 @@ intel_ddi_transcoder_func_reg_val_get(const struct intel_crtc_state *crtc_state)
 		temp |= TRANS_DDI_MODE_SELECT_DP_MST;
 		temp |= DDI_PORT_WIDTH(crtc_state->lane_count);
 
-		if (INTEL_GEN(dev_priv) >= 12)
-			temp |= TRANS_DDI_MST_TRANSPORT_SELECT(crtc_state->cpu_transcoder);
+		if (INTEL_GEN(dev_priv) >= 12) {
+			enum transcoder master;
+
+			master = crtc_state->mst_master_transcoder;
+			WARN_ON(master == INVALID_TRANSCODER);
+			temp |= TRANS_DDI_MST_TRANSPORT_SELECT(master);
+		}
 	} else {
 		temp |= TRANS_DDI_MODE_SELECT_DP_SST;
 		temp |= DDI_PORT_WIDTH(crtc_state->lane_count);
@@ -4372,6 +4377,11 @@ void intel_ddi_get_config(struct intel_encoder *encoder,
 		pipe_config->output_types |= BIT(INTEL_OUTPUT_DP_MST);
 		pipe_config->lane_count =
 			((temp & DDI_PORT_WIDTH_MASK) >> DDI_PORT_WIDTH_SHIFT) + 1;
+
+		if (INTEL_GEN(dev_priv) >= 12)
+			pipe_config->mst_master_transcoder =
+					REG_FIELD_GET(TRANS_DDI_MST_TRANSPORT_SELECT_MASK, temp);
+
 		intel_dp_get_m_n(intel_crtc, pipe_config);
 		break;
 	default:
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 821ba8053f9d..f89494c849ce 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -46,6 +46,7 @@
 #include "display/intel_crt.h"
 #include "display/intel_ddi.h"
 #include "display/intel_dp.h"
+#include "display/intel_dp_mst.h"
 #include "display/intel_dsi.h"
 #include "display/intel_dvo.h"
 #include "display/intel_gmbus.h"
@@ -12542,6 +12543,11 @@ static void intel_dump_pipe_config(const struct intel_crtc_state *pipe_config,
 			      pipe_config->csc_mode, pipe_config->gamma_mode,
 			      pipe_config->gamma_enable, pipe_config->csc_enable);
 
+	if (INTEL_GEN(dev_priv) >= 12 &&
+	    intel_crtc_has_type(pipe_config, INTEL_OUTPUT_DP_MST))
+		DRM_DEBUG_KMS("MST master transcoder: %s\n",
+			      transcoder_name(pipe_config->mst_master_transcoder));
+
 dump_planes:
 	if (!state)
 		return;
@@ -13318,6 +13324,10 @@ intel_pipe_config_compare(const struct intel_crtc_state *current_config,
 	PIPE_CONF_CHECK_I(sync_mode_slaves_mask);
 	PIPE_CONF_CHECK_I(master_transcoder);
 
+	if (INTEL_GEN(dev_priv) >= 12 &&
+	    intel_crtc_has_type(pipe_config, INTEL_OUTPUT_DP_MST))
+		PIPE_CONF_CHECK_I(mst_master_transcoder);
+
 #undef PIPE_CONF_CHECK_X
 #undef PIPE_CONF_CHECK_I
 #undef PIPE_CONF_CHECK_BOOL
@@ -14406,7 +14416,7 @@ static void intel_commit_modeset_disables(struct intel_atomic_state *state)
 	u32 handled = 0;
 	int i;
 
-	/* Only disable port sync slaves */
+	/* Only disable port sync and MST slaves */
 	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
 					    new_crtc_state, i) {
 		if (!needs_modeset(new_crtc_state))
@@ -14420,7 +14430,8 @@ static void intel_commit_modeset_disables(struct intel_atomic_state *state)
 		 * slave CRTCs are disabled first and then master CRTC since
 		 * Slave vblanks are masked till Master Vblanks.
 		 */
-		if (!is_trans_port_sync_slave(old_crtc_state))
+		if (!is_trans_port_sync_slave(old_crtc_state) &&
+		    !intel_dp_mst_is_slave_trans(old_crtc_state))
 			continue;
 
 		intel_pre_plane_update(state, crtc);
diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 83ea04149b77..630a94892b7b 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -1054,6 +1054,9 @@ struct intel_crtc_state {
 
 	/* Bitmask to indicate slaves attached */
 	u8 sync_mode_slaves_mask;
+
+	/* Only valid on TGL+ */
+	enum transcoder mst_master_transcoder;
 };
 
 struct intel_crtc {
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index 926e49f449a6..49f1518e3ab9 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -87,6 +87,49 @@ static int intel_dp_mst_compute_link_config(struct intel_encoder *encoder,
 	return 0;
 }
 
+/*
+ * Iterate over all the CRTCs and set mst_master_transcoder to the first active
+ * transcoder that shares the same MST connector.
+ *
+ * TODO: maybe this could be optimized to keep the old master transcoder
+ */
+static int
+intel_dp_mst_master_trans_compute(struct intel_encoder *encoder,
+				  struct intel_crtc_state *pipe_config,
+				  struct drm_connector_state *conn_state)
+{
+	struct intel_atomic_state *state = to_intel_atomic_state(pipe_config->uapi.state);
+	struct intel_connector *conn = to_intel_connector(conn_state->connector);
+	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
+	struct intel_digital_connector_state *iter_conn_state;
+	struct intel_connector *iter_conn;
+	int i;
+
+	if (INTEL_GEN(dev_priv) < 12)
+		return 0;
+
+	for_each_new_intel_connector_in_state(state, iter_conn,
+					      iter_conn_state, i) {
+		struct intel_crtc_state *iter_crtc_state;
+		struct intel_crtc *iter_crtc;
+
+		if (conn->mst_port != iter_conn->mst_port ||
+		    !iter_conn_state->base.crtc)
+			continue;
+
+		iter_crtc = to_intel_crtc(iter_conn_state->base.crtc);
+		iter_crtc_state = intel_atomic_get_new_crtc_state(state,
+								  iter_crtc);
+		if (!iter_crtc_state->uapi.active)
+			continue;
+
+		pipe_config->mst_master_transcoder = iter_crtc_state->cpu_transcoder;
+		break;
+	}
+
+	return 0;
+}
+
 static int intel_dp_mst_compute_config(struct intel_encoder *encoder,
 				       struct intel_crtc_state *pipe_config,
 				       struct drm_connector_state *conn_state)
@@ -154,6 +197,98 @@ static int intel_dp_mst_compute_config(struct intel_encoder *encoder,
 
 	intel_ddi_compute_min_voltage_level(dev_priv, pipe_config);
 
+	ret = intel_dp_mst_master_trans_compute(encoder, pipe_config,
+						conn_state);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int
+intel_dp_mst_atomic_master_trans_check(struct drm_connector *connector,
+				       struct drm_atomic_state *state)
+{
+	struct drm_i915_private *dev_priv = to_i915(connector->dev);
+	struct drm_connector_state *new_conn_state, *old_conn_state;
+	struct drm_connector_list_iter conn_list_iter;
+	struct intel_crtc_state *intel_crtc_state;
+	struct intel_connector *intel_conn;
+	struct drm_crtc_state *crtc_state;
+	struct drm_connector *conn_iter;
+
+	if (INTEL_GEN(dev_priv) < 12)
+		return  0;
+
+	intel_conn = to_intel_connector(connector);
+	new_conn_state = drm_atomic_get_new_connector_state(state, connector);
+	old_conn_state = drm_atomic_get_old_connector_state(state, connector);
+
+	if (!old_conn_state->crtc && !new_conn_state->crtc)
+		return 0;
+
+	/*
+	 * 3 cases that needs be handled here:
+	 * - connector going from disabled to enabled:
+	 * nothing else need to be done, drm helpers already set mode_changed in
+	 * the CRTCs needed
+	 * - connector going from enabled to disabled:
+	 * if this transcoder was the master, all slaves needs a modeset
+	 * - connector going from enabled to enabled but it needs a modeset:
+	 * if this transcoder was the master, all slaves also needs a modeset
+	 */
+
+	/* disabled -> enabled */
+	if (!old_conn_state->crtc && new_conn_state->crtc)
+		return 0;
+
+	/* enabled -> enabled(modeset)? */
+	if (new_conn_state->crtc) {
+		crtc_state = drm_atomic_get_new_crtc_state(state,
+							   new_conn_state->crtc);
+		if (!drm_atomic_crtc_needs_modeset(crtc_state))
+			return 0;
+	}
+
+	/* handling enabled -> enabled(modeset) and enabled -> disabled */
+	crtc_state = drm_atomic_get_old_crtc_state(state, old_conn_state->crtc);
+	intel_crtc_state = to_intel_crtc_state(crtc_state);
+
+	/* If not master, nothing else needs to be handled */
+	if (!intel_dp_mst_is_master_trans(intel_crtc_state))
+		return 0;
+
+	/* It is master, add and mark all other CRTCs in the stream as changed */
+	drm_connector_list_iter_begin(state->dev, &conn_list_iter);
+	drm_for_each_connector_iter(conn_iter, &conn_list_iter) {
+		struct drm_connector_state *conn_iter_state;
+		struct intel_connector *intel_conn_iter;
+
+		intel_conn_iter = to_intel_connector(conn_iter);
+		if (intel_conn_iter->mst_port != intel_conn->mst_port)
+			continue;
+
+		conn_iter_state = drm_atomic_get_connector_state(state,
+								 conn_iter);
+		if (IS_ERR(conn_iter_state)) {
+			drm_connector_list_iter_end(&conn_list_iter);
+			return PTR_ERR(conn_iter_state);
+		}
+
+		if (!conn_iter_state->crtc)
+			continue;
+
+		crtc_state = drm_atomic_get_crtc_state(state,
+						       conn_iter_state->crtc);
+		if (IS_ERR(crtc_state)) {
+			drm_connector_list_iter_end(&conn_list_iter);
+			return PTR_ERR(conn_iter_state);
+		}
+
+		crtc_state->mode_changed = true;
+	}
+	drm_connector_list_iter_end(&conn_list_iter);
+
 	return 0;
 }
 
@@ -175,6 +310,10 @@ intel_dp_mst_atomic_check(struct drm_connector *connector,
 	if (ret)
 		return ret;
 
+	ret = intel_dp_mst_atomic_master_trans_check(connector, state);
+	if (ret)
+		return ret;
+
 	if (!old_conn_state->crtc)
 		return 0;
 
@@ -241,6 +380,9 @@ static void intel_mst_post_disable_dp(struct intel_encoder *encoder,
 	intel_dp->active_mst_links--;
 	last_mst_stream = intel_dp->active_mst_links == 0;
 
+	WARN_ON(INTEL_GEN(dev_priv) >= 12 && last_mst_stream &&
+		!intel_dp_mst_is_master_trans(old_crtc_state));
+
 	/*
 	 * From TGL spec: "If multi-stream slave transcoder: Configure
 	 * Transcoder Clock Select to direct no clock to the transcoder"
@@ -321,6 +463,9 @@ static void intel_mst_pre_enable_dp(struct intel_encoder *encoder,
 	intel_mst->connector = connector;
 	first_mst_stream = intel_dp->active_mst_links == 0;
 
+	WARN_ON(INTEL_GEN(dev_priv) >= 12 && first_mst_stream &&
+		!intel_dp_mst_is_master_trans(pipe_config));
+
 	DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links);
 
 	if (first_mst_stream)
@@ -726,3 +871,21 @@ intel_dp_mst_encoder_cleanup(struct intel_digital_port *intel_dig_port)
 	drm_dp_mst_topology_mgr_destroy(&intel_dp->mst_mgr);
 	/* encoders will get killed by normal cleanup */
 }
+
+bool intel_dp_mst_is_master_trans(const struct intel_crtc_state *crtc_state)
+{
+	struct drm_i915_private *dev_priv = to_i915(crtc_state->uapi.crtc->dev);
+
+	return INTEL_GEN(dev_priv) >= 12 &&
+	       intel_crtc_has_type(crtc_state, INTEL_OUTPUT_DP_MST) &&
+	       crtc_state->mst_master_transcoder == crtc_state->cpu_transcoder;
+}
+
+bool intel_dp_mst_is_slave_trans(const struct intel_crtc_state *crtc_state)
+{
+	struct drm_i915_private *dev_priv = to_i915(crtc_state->uapi.crtc->dev);
+
+	return INTEL_GEN(dev_priv) >= 12 &&
+	       intel_crtc_has_type(crtc_state, INTEL_OUTPUT_DP_MST) &&
+	       crtc_state->mst_master_transcoder != crtc_state->cpu_transcoder;
+}
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.h b/drivers/gpu/drm/i915/display/intel_dp_mst.h
index f660ad80db04..e40767f78343 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.h
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.h
@@ -6,10 +6,15 @@
 #ifndef __INTEL_DP_MST_H__
 #define __INTEL_DP_MST_H__
 
+#include <stdbool.h>
+
 struct intel_digital_port;
+struct intel_crtc_state;
 
 int intel_dp_mst_encoder_init(struct intel_digital_port *intel_dig_port, int conn_id);
 void intel_dp_mst_encoder_cleanup(struct intel_digital_port *intel_dig_port);
 int intel_dp_mst_encoder_active_links(struct intel_digital_port *intel_dig_port);
+bool intel_dp_mst_is_master_trans(const struct intel_crtc_state *crtc_state);
+bool intel_dp_mst_is_slave_trans(const struct intel_crtc_state *crtc_state);
 
 #endif /* __INTEL_DP_MST_H__ */
