Commit 84a8b390 authored by Wayne Lin's avatar Wayne Lin Committed by Alex Deucher
Browse files

drm/amd/display: Release remote dc_sink under mst scenario 



[Why]
Observe that we have several problems while releasing remote dc_sink
under mst cases.

- When unplug mst branch device from the source, we now try to free all
  remote dc_sinks in dm_helpers_dp_mst_stop_top_mgr(). However, there are
  bugs while we're releasing dc_sinks here. First of all,
  link->remote_sinks[] array get shuffled within
  dc_link_remove_remote_sink(). As the result, increasing the array index
  within the releasing loop is wrong. Secondly, it tries to call
  dc_sink_release() to release the dc_sink of the same aconnector every
  time in the loop. Which can't release dc_sink of all aconnector in the
  mst topology.
- There is no code path for us to release remote dc_sink for disconnected
  sst monitor which unplug event is notified by CSN sideband message. Which
  means we'll use stale dc_sink data to represent later on connected
  monitor. Also, has chance to break the maximum remote dc_sink number
  constraint.

[How]
Distinguish unplug event of mst scenario into 2 cases.

* Unplug sst/legacy stream sink off the mst topology
- Release related remote dc_sink in detec_ctx().

* Unplug mst branch device off the mst topology
- Release related remote dc_sink in early_unregister()

Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: default avatarAurabindo Jayamohanan Pillai <Aurabindo.Pillai@amd.com>
Acked-by: default avatarRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Acked-by: default avatarLyude Paul <lyude@redhat.com>
Signed-off-by: default avatarWayne Lin <Wayne.Lin@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 052eaf6a

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

+3 −2
Original line number Diff line number Diff line
@@ -2201,7 +2201,8 @@ static void s3_handle_mst(struct drm_device *dev, bool suspend) 
		} else {

			ret = drm_dp_mst_topology_mgr_resume(mgr, true);

			if (ret < 0) {

				drm_dp_mst_topology_mgr_set_mst(mgr, false);

				dm_helpers_dp_mst_stop_top_mgr(aconnector->dc_link->ctx,

					aconnector->dc_link);

				need_hotplug = true;

			}

		}
@@ -10606,7 +10607,7 @@ static int dm_update_crtc_state(struct amdgpu_display_manager *dm, 
		 * added MST connectors not found in existing crtc_state in the chained mode

		 * TODO: need to dig out the root cause of that

		 */

		if (!aconnector || (!aconnector->dc_sink && aconnector->mst_port))

		if (!aconnector)

			goto skip_modeset;



		if (modereset_required(new_crtc_state))

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

+1 −17
Original line number Diff line number Diff line
@@ -451,7 +451,6 @@ bool dm_helpers_dp_mst_stop_top_mgr( 
		struct dc_link *link)

{

	struct amdgpu_dm_connector *aconnector = link->priv;

	uint8_t i;



	if (!aconnector) {

		DRM_ERROR("Failed to find connector for link!");
@@ -463,22 +462,7 @@ bool dm_helpers_dp_mst_stop_top_mgr( 


	if (aconnector->mst_mgr.mst_state == true) {

		drm_dp_mst_topology_mgr_set_mst(&aconnector->mst_mgr, false);



		for (i = 0; i < MAX_SINKS_PER_LINK; i++) {

			if (link->remote_sinks[i] == NULL)

				continue;



			if (link->remote_sinks[i]->sink_signal ==

			    SIGNAL_TYPE_DISPLAY_PORT_MST) {

				dc_link_remove_remote_sink(link, link->remote_sinks[i]);



				if (aconnector->dc_sink) {

					dc_sink_release(aconnector->dc_sink);

					aconnector->dc_sink = NULL;

					aconnector->dc_link->cur_link_settings.lane_count = 0;

				}

			}

		}

		link->cur_link_settings.lane_count = 0;

	}



	return false;

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

+31 −3
Original line number Diff line number Diff line
@@ -140,11 +140,28 @@ amdgpu_dm_mst_connector_late_register(struct drm_connector *connector) 
static void

amdgpu_dm_mst_connector_early_unregister(struct drm_connector *connector)

{

	struct amdgpu_dm_connector *amdgpu_dm_connector =

	struct amdgpu_dm_connector *aconnector =

		to_amdgpu_dm_connector(connector);

	struct drm_dp_mst_port *port = amdgpu_dm_connector->port;

	struct drm_dp_mst_port *port = aconnector->port;

	struct amdgpu_dm_connector *root = aconnector->mst_port;

	struct dc_link *dc_link = aconnector->dc_link;

	struct dc_sink *dc_sink = aconnector->dc_sink;



	drm_dp_mst_connector_early_unregister(connector, port);



	/*

	 * Release dc_sink for connector which its attached port is

	 * no longer in the mst topology

	 */

	drm_modeset_lock(&root->mst_mgr.base.lock, NULL);

	if (dc_sink) {

		if (dc_link->sink_count)

			dc_link_remove_remote_sink(dc_link, dc_sink);



		dc_sink_release(dc_sink);

		aconnector->dc_sink = NULL;

	}

	drm_modeset_unlock(&root->mst_mgr.base.lock);

}



static const struct drm_connector_funcs dm_dp_mst_connector_funcs = {
@@ -385,6 +402,17 @@ dm_dp_mst_detect(struct drm_connector *connector, 
		port->dpcd_rev = 0;

	}



	/*

	 * Release dc_sink for connector which unplug event is notified by CSN msg

	 */

	if (connection_status == connector_status_disconnected && aconnector->dc_sink) {

		if (aconnector->dc_link->sink_count)

			dc_link_remove_remote_sink(aconnector->dc_link, aconnector->dc_sink);



		dc_sink_release(aconnector->dc_sink);

		aconnector->dc_sink = NULL;

	}



	return connection_status;

}