drm/amd/display: adjust flow for deallocation mst payload

[Why]
MST relevant variables are maintained at drm side. As the result, we
still have to call drm_dp_remove_payload_part2() to update the relevant
values regardless the link is under mst mode or not. We used to have a
workaround patch to tackle this: commit 3d8fcc67 ("drm/amd/display:
Extract temp drm mst deallocation wa into its own function")

Now it's time to remove the workaround and adjust the flow.

[How]
During deallocate_mst_payload(), source actually doesn't send out
ALLOCATE_PAYLOAD at the end as like the flow in allocate_mst_payload().
Call function dm_helpers_dp_mst_send_payload_allocation() at the end of
deallocate_mst_payload() is a bit confusing.

Separate dm_helpers_dp_mst_send_payload_allocation() into 2 functions.
Have a new function dm_helpers_dp_mst_update_mst_mgr_for_deallocation()
to replace dm_helpers_dp_mst_send_payload_allocation() for payload
deallocation.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Wayne Lin <wayne.lin@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -1715,23 +1715,6 @@ static int amdgpu_dm_init(struct amdgpu_device *adev)
 	/* TODO: Remove after DP2 receiver gets proper support of Cable ID feature */
 	adev->dm.dc->debug.ignore_cable_id = true;
 
-	/* TODO: There is a new drm mst change where the freedom of
-	 * vc_next_start_slot update is revoked/moved into drm, instead of in
-	 * driver. This forces us to make sure to get vc_next_start_slot updated
-	 * in drm function each time without considering if mst_state is active
-	 * or not. Otherwise, next time hotplug will give wrong start_slot
-	 * number. We are implementing a temporary solution to even notify drm
-	 * mst deallocation when link is no longer of MST type when uncommitting
-	 * the stream so we will have more time to work on a proper solution.
-	 * Ideally when dm_helpers_dp_mst_stop_top_mgr message is triggered, we
-	 * should notify drm to do a complete "reset" of its states and stop
-	 * calling further drm mst functions when link is no longer of an MST
-	 * type. This could happen when we unplug an MST hubs/displays. When
-	 * uncommit stream comes later after unplug, we should just reset
-	 * hardware states only.
-	 */
-	adev->dm.dc->debug.temp_mst_deallocation_sequence = true;
-
 	if (adev->dm.dc->caps.dp_hdmi21_pcon_support)
 		DRM_INFO("DP-HDMI FRL PCON supported\n");
 

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

@@ -333,15 +333,14 @@ enum act_return_status dm_helpers_dp_mst_poll_for_allocation_change_trigger(
 	return ACT_SUCCESS;
 }
 
-bool dm_helpers_dp_mst_send_payload_allocation(
+void dm_helpers_dp_mst_send_payload_allocation(
 		struct dc_context *ctx,
-		const struct dc_stream_state *stream,
-		bool enable)
+		const struct dc_stream_state *stream)
 {
 	struct amdgpu_dm_connector *aconnector;
 	struct drm_dp_mst_topology_state *mst_state;
 	struct drm_dp_mst_topology_mgr *mst_mgr;
-	struct drm_dp_mst_atomic_payload *new_payload, old_payload;
+	struct drm_dp_mst_atomic_payload *new_payload;
 	enum mst_progress_status set_flag = MST_ALLOCATE_NEW_PAYLOAD;
 	enum mst_progress_status clr_flag = MST_CLEAR_ALLOCATED_PAYLOAD;
 	int ret = 0;
@@ -349,25 +348,13 @@ bool dm_helpers_dp_mst_send_payload_allocation(
 	aconnector = (struct amdgpu_dm_connector *)stream->dm_stream_context;
 
 	if (!aconnector || !aconnector->mst_root)
-		return false;
+		return;
 
 	mst_mgr = &aconnector->mst_root->mst_mgr;
 	mst_state = to_drm_dp_mst_topology_state(mst_mgr->base.state);
-
 	new_payload = drm_atomic_get_mst_payload_state(mst_state, aconnector->mst_output_port);
 
-	if (!enable) {
-		set_flag = MST_CLEAR_ALLOCATED_PAYLOAD;
-		clr_flag = MST_ALLOCATE_NEW_PAYLOAD;
-	}
-
-	if (enable) {
-		ret = drm_dp_add_payload_part2(mst_mgr, mst_state->base.state, new_payload);
-	} else {
-		dm_helpers_construct_old_payload(mst_mgr, mst_state,
-						 new_payload, &old_payload);
-		drm_dp_remove_payload_part2(mst_mgr, mst_state, &old_payload, new_payload);
-	}
+	ret = drm_dp_add_payload_part2(mst_mgr, mst_state->base.state, new_payload);
 
 	if (ret) {
 		amdgpu_dm_set_mst_status(&aconnector->mst_status,
@@ -378,10 +365,36 @@ bool dm_helpers_dp_mst_send_payload_allocation(
 		amdgpu_dm_set_mst_status(&aconnector->mst_status,
 			clr_flag, false);
 	}
-
-	return true;
 }
 
+void dm_helpers_dp_mst_update_mst_mgr_for_deallocation(
+		struct dc_context *ctx,
+		const struct dc_stream_state *stream)
+{
+	struct amdgpu_dm_connector *aconnector;
+	struct drm_dp_mst_topology_state *mst_state;
+	struct drm_dp_mst_topology_mgr *mst_mgr;
+	struct drm_dp_mst_atomic_payload *new_payload, old_payload;
+	enum mst_progress_status set_flag = MST_CLEAR_ALLOCATED_PAYLOAD;
+	enum mst_progress_status clr_flag = MST_ALLOCATE_NEW_PAYLOAD;
+
+	aconnector = (struct amdgpu_dm_connector *)stream->dm_stream_context;
+
+	if (!aconnector || !aconnector->mst_root)
+		return;
+
+	mst_mgr = &aconnector->mst_root->mst_mgr;
+	mst_state = to_drm_dp_mst_topology_state(mst_mgr->base.state);
+	new_payload = drm_atomic_get_mst_payload_state(mst_state, aconnector->mst_output_port);
+	dm_helpers_construct_old_payload(mst_mgr, mst_state,
+					 new_payload, &old_payload);
+
+	drm_dp_remove_payload_part2(mst_mgr, mst_state, &old_payload, new_payload);
+
+	amdgpu_dm_set_mst_status(&aconnector->mst_status, set_flag, true);
+	amdgpu_dm_set_mst_status(&aconnector->mst_status, clr_flag, false);
+ }
+
 void dm_dtn_log_begin(struct dc_context *ctx,
 	struct dc_log_buffer_ctx *log_ctx)
 {

drivers/gpu/drm/amd/display/dc/dc.h

@@ -956,7 +956,6 @@ struct dc_debug_options {
 	unsigned int min_prefetch_in_strobe_ns;
 	bool disable_unbounded_requesting;
 	bool dig_fifo_off_in_blank;
-	bool temp_mst_deallocation_sequence;
 	bool override_dispclk_programming;
 	bool otg_crc_db;
 	bool disallow_dispclk_dppclk_ds;

drivers/gpu/drm/amd/display/dc/dm_helpers.h

@@ -103,10 +103,16 @@ enum act_return_status dm_helpers_dp_mst_poll_for_allocation_change_trigger(
 /*
  * Sends ALLOCATE_PAYLOAD message.
  */
-bool dm_helpers_dp_mst_send_payload_allocation(
+void dm_helpers_dp_mst_send_payload_allocation(
 		struct dc_context *ctx,
-		const struct dc_stream_state *stream,
-		bool enable);
+		const struct dc_stream_state *stream);
+
+/*
+ * Update mst manager relevant variables
+ */
+void dm_helpers_dp_mst_update_mst_mgr_for_deallocation(
+		struct dc_context *ctx,
+		const struct dc_stream_state *stream);
 
 bool dm_helpers_dp_mst_start_top_mgr(
 		struct dc_context *ctx,

drivers/gpu/drm/amd/display/dc/link/link_dpms.c

@@ -1247,86 +1247,6 @@ static void remove_stream_from_alloc_table(
 	}
 }
 
-static enum dc_status deallocate_mst_payload_with_temp_drm_wa(
-		struct pipe_ctx *pipe_ctx)
-{
-	struct dc_stream_state *stream = pipe_ctx->stream;
-	struct dc_link *link = stream->link;
-	struct dc_dp_mst_stream_allocation_table proposed_table = {0};
-	struct fixed31_32 avg_time_slots_per_mtp = dc_fixpt_from_int(0);
-	int i;
-	bool mst_mode = (link->type == dc_connection_mst_branch);
-	/* adjust for drm changes*/
-	const struct link_hwss *link_hwss = get_link_hwss(link, &pipe_ctx->link_res);
-	const struct dc_link_settings empty_link_settings = {0};
-	DC_LOGGER_INIT(link->ctx->logger);
-
-	if (link_hwss->ext.set_throttled_vcp_size)
-		link_hwss->ext.set_throttled_vcp_size(pipe_ctx, avg_time_slots_per_mtp);
-	if (link_hwss->ext.set_hblank_min_symbol_width)
-		link_hwss->ext.set_hblank_min_symbol_width(pipe_ctx,
-				&empty_link_settings,
-				avg_time_slots_per_mtp);
-
-	if (dm_helpers_dp_mst_write_payload_allocation_table(
-			stream->ctx,
-			stream,
-			&proposed_table,
-			false))
-		update_mst_stream_alloc_table(
-				link,
-				pipe_ctx->stream_res.stream_enc,
-				pipe_ctx->stream_res.hpo_dp_stream_enc,
-				&proposed_table);
-	else
-		DC_LOG_WARNING("Failed to update"
-				"MST allocation table for"
-				"pipe idx:%d\n",
-				pipe_ctx->pipe_idx);
-
-	DC_LOG_MST("%s"
-			"stream_count: %d: ",
-			__func__,
-			link->mst_stream_alloc_table.stream_count);
-
-	for (i = 0; i < MAX_CONTROLLER_NUM; i++) {
-		DC_LOG_MST("stream_enc[%d]: %p      "
-		"stream[%d].hpo_dp_stream_enc: %p      "
-		"stream[%d].vcp_id: %d      "
-		"stream[%d].slot_count: %d\n",
-		i,
-		(void *) link->mst_stream_alloc_table.stream_allocations[i].stream_enc,
-		i,
-		(void *) link->mst_stream_alloc_table.stream_allocations[i].hpo_dp_stream_enc,
-		i,
-		link->mst_stream_alloc_table.stream_allocations[i].vcp_id,
-		i,
-		link->mst_stream_alloc_table.stream_allocations[i].slot_count);
-	}
-
-	if (link_hwss->ext.update_stream_allocation_table == NULL ||
-			link_dp_get_encoding_format(&link->cur_link_settings) == DP_UNKNOWN_ENCODING) {
-		DC_LOG_DEBUG("Unknown encoding format\n");
-		return DC_ERROR_UNEXPECTED;
-	}
-
-	link_hwss->ext.update_stream_allocation_table(link, &pipe_ctx->link_res,
-			&link->mst_stream_alloc_table);
-
-	if (mst_mode) {
-		dm_helpers_dp_mst_poll_for_allocation_change_trigger(
-			stream->ctx,
-			stream);
-	}
-
-	dm_helpers_dp_mst_send_payload_allocation(
-			stream->ctx,
-			stream,
-			false);
-
-	return DC_OK;
-}
-
 static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 {
 	struct dc_stream_state *stream = pipe_ctx->stream;
@@ -1339,9 +1259,6 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 	const struct dc_link_settings empty_link_settings = {0};
 	DC_LOGGER_INIT(link->ctx->logger);
 
-	if (link->dc->debug.temp_mst_deallocation_sequence)
-		return deallocate_mst_payload_with_temp_drm_wa(pipe_ctx);
-
 	/* deallocate_mst_payload is called before disable link. When mode or
 	 * disable/enable monitor, new stream is created which is not in link
 	 * stream[] yet. For this, payload is not allocated yet, so de-alloc
@@ -1414,16 +1331,14 @@ static enum dc_status deallocate_mst_payload(struct pipe_ctx *pipe_ctx)
 	link_hwss->ext.update_stream_allocation_table(link, &pipe_ctx->link_res,
 			&link->mst_stream_alloc_table);
 
-	if (mst_mode) {
+	if (mst_mode)
 		dm_helpers_dp_mst_poll_for_allocation_change_trigger(
 			stream->ctx,
 			stream);
 
-		dm_helpers_dp_mst_send_payload_allocation(
-				stream->ctx,
-				stream,
-				false);
-	}
+	dm_helpers_dp_mst_update_mst_mgr_for_deallocation(
+			stream->ctx,
+			stream);
 
 	return DC_OK;
 }
@@ -1504,12 +1419,10 @@ static enum dc_status allocate_mst_payload(struct pipe_ctx *pipe_ctx)
 			stream->ctx,
 			stream);
 
-	if (ret != ACT_LINK_LOST) {
+	if (ret != ACT_LINK_LOST)
 		dm_helpers_dp_mst_send_payload_allocation(
 				stream->ctx,
-				stream,
-				true);
-	}
+				stream);
 
 	/* slot X.Y for only current stream */
 	pbn_per_slot = get_pbn_per_slot(stream);
@@ -1769,8 +1682,7 @@ enum dc_status link_reduce_mst_payload(struct pipe_ctx *pipe_ctx, uint32_t bw_in
 	/* send ALLOCATE_PAYLOAD sideband message with updated pbn */
 	dm_helpers_dp_mst_send_payload_allocation(
 			stream->ctx,
-			stream,
-			true);
+			stream);
 
 	/* notify immediate branch device table update */
 	if (dm_helpers_dp_mst_write_payload_allocation_table(
@@ -1899,8 +1811,7 @@ enum dc_status link_increase_mst_payload(struct pipe_ctx *pipe_ctx, uint32_t bw_
 		/* send ALLOCATE_PAYLOAD sideband message with updated pbn */
 		dm_helpers_dp_mst_send_payload_allocation(
 				stream->ctx,
-				stream,
-				true);
+				stream);
 	}
 
 	/* increase throttled vcp size */