Commit fbc0c790 authored by Wenjing Liu's avatar Wenjing Liu Committed by Alex Deucher
Browse files

drm/amd/display: do not set RX back to SST mode for non 0 mst stream count 



[why]
a recent regression has caused us to mistakenly switch RX back to SST mode
when there are remaining mst stream enabled to the link. We are missing
a condition check for stream count before setting RX back to SST mode.

[how]
Add stream count check condition back and do some further refactor so the
logic is easier to understand to prevent future coding error in this sequence.

Reviewed-by: default avatarSamson Tam <Samson.Tam@amd.com>
Acked-by: default avatarQingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: default avatarWenjing Liu <wenjing.liu@amd.com>
Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 3a615704

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

+25 −26
Original line number Diff line number Diff line
@@ -1782,37 +1782,36 @@ enum dc_status link_increase_mst_payload(struct pipe_ctx *pipe_ctx, uint32_t bw_ 
	return DC_OK;

}



static void disable_link(struct dc_link *link, const struct link_resource *link_res,

static void disable_link_dp(struct dc_link *link,

		const struct link_resource *link_res,

		enum signal_type signal)

{

	/*

	 * TODO: implement call for dp_set_hw_test_pattern

	 * it is needed for compliance testing

	 */

	struct dc_link_settings link_settings = link->cur_link_settings;



	/* Here we need to specify that encoder output settings

	 * need to be calculated as for the set mode,

	 * it will lead to querying dynamic link capabilities

	 * which should be done before enable output

	 */

	if (signal == SIGNAL_TYPE_DISPLAY_PORT_MST &&

			link->mst_stream_alloc_table.stream_count > 0)

		/* disable MST link only when last vc payload is deallocated */

		return;



	if (dc_is_dp_signal(signal)) {

		/* SST DP, eDP */

		struct dc_link_settings link_settings = link->cur_link_settings;

		if (dc_is_dp_sst_signal(signal)) {

	dp_disable_link_phy(link, link_res, signal);

		} else {

			dp_disable_link_phy_mst(link, link_res, signal);



	if (signal == SIGNAL_TYPE_DISPLAY_PORT_MST)

		/* set the sink to SST mode after disabling the link */

		enable_mst_on_sink(link, false);

		}

		if (dc_is_dp_sst_signal(signal) ||

				link->mst_stream_alloc_table.stream_count == 0) {

			if (link_dp_get_encoding_format(&link_settings) == DP_8b_10b_ENCODING) {



	if (link_dp_get_encoding_format(&link_settings) ==

			DP_8b_10b_ENCODING) {

		dp_set_fec_enable(link, false);

		dp_set_fec_ready(link, link_res, false);

	}

}



static void disable_link(struct dc_link *link,

		const struct link_resource *link_res,

		enum signal_type signal)

{

	if (dc_is_dp_signal(signal)) {

		disable_link_dp(link, link_res, signal);

	} else if (signal != SIGNAL_TYPE_VIRTUAL) {

		link->dc->hwss.disable_link_output(link, link_res, signal);

	}

drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c

+0 −11
Original line number Diff line number Diff line
@@ -85,17 +85,6 @@ void dp_disable_link_phy(struct dc_link *link, 
		dc->clk_mgr->funcs->notify_link_rate_change(dc->clk_mgr, link);

}



void dp_disable_link_phy_mst(struct dc_link *link,

		const struct link_resource *link_res,

		enum signal_type signal)

{

	/* MST disable link only when no stream use the link */

	if (link->mst_stream_alloc_table.stream_count > 0)

		return;



	dp_disable_link_phy(link, link_res, signal);

}



static inline bool is_immediate_downstream(struct dc_link *link, uint32_t offset)

{

	return (dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt) ==

drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.h

+0 −4
Original line number Diff line number Diff line
@@ -38,10 +38,6 @@ void dp_disable_link_phy(struct dc_link *link, 
		const struct link_resource *link_res,

		enum signal_type signal);



void dp_disable_link_phy_mst(struct dc_link *link,

		const struct link_resource *link_res,

		enum signal_type signal);



void dp_set_hw_lane_settings(

		struct dc_link *link,

		const struct link_resource *link_res,