Commit 61f14c5b authored by Lucy Li's avatar Lucy Li Committed by Alex Deucher
Browse files

drm/amd/display: Disable link before reenable 



[Why]
Black screen seen after display is disabled then re-enabled.
Caused by difference in link settings when
switching between different resolutions.

[How]
In PnP case, or whenever the display is
still enabled but the driver is unloaded,
disable link before re-enabling with new link settings.

Signed-off-by: default avatarLucy Li <lucy.li@amd.com>
Reviewed-by: default avatarAnthony Koo <Anthony.Koo@amd.com>
Acked-by: default avatarLeo Li <sunpeng.li@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 832aa63b

drivers/gpu/drm/amd/display/dc/core/dc_link.c

+52 −47
Original line number Diff line number Diff line
@@ -1511,15 +1511,6 @@ static enum dc_status enable_link_dp( 
	decide_link_settings(stream, &link_settings);



	if (pipe_ctx->stream->signal == SIGNAL_TYPE_EDP) {

		/* If link settings are different than current and link already enabled

		 * then need to disable before programming to new rate.

		 */

		if (link->link_status.link_active &&

			(link->cur_link_settings.lane_count != link_settings.lane_count ||

			 link->cur_link_settings.link_rate != link_settings.link_rate)) {

			dp_disable_link_phy(link, pipe_ctx->stream->signal);

		}



		/*in case it is not on*/

		link->dc->hwss.edp_power_control(link, true);

		link->dc->hwss.edp_wait_for_hpd_ready(link, true);
@@ -2039,6 +2030,45 @@ static void write_i2c_redriver_setting( 
		ASSERT(i2c_success);

}



static void disable_link(struct dc_link *link, enum signal_type signal)

{

	/*

	 * TODO: implement call for dp_set_hw_test_pattern

	 * it is needed for compliance testing

	 */



	/* 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 (dc_is_dp_signal(signal)) {

		/* SST DP, eDP */

		if (dc_is_dp_sst_signal(signal))

			dp_disable_link_phy(link, signal);

		else

			dp_disable_link_phy_mst(link, signal);



		if (dc_is_dp_sst_signal(signal) ||

				link->mst_stream_alloc_table.stream_count == 0) {

			dp_set_fec_enable(link, false);

			dp_set_fec_ready(link, false);

		}

	} else {

		if (signal != SIGNAL_TYPE_VIRTUAL)

			link->link_enc->funcs->disable_output(link->link_enc, signal);

	}



	if (signal == SIGNAL_TYPE_DISPLAY_PORT_MST) {

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

		if (link->mst_stream_alloc_table.stream_count <= 0)

			link->link_status.link_active = false;

	} else {

		link->link_status.link_active = false;

	}

}



static void enable_link_hdmi(struct pipe_ctx *pipe_ctx)

{

	struct dc_stream_state *stream = pipe_ctx->stream;
@@ -2123,6 +2153,19 @@ static enum dc_status enable_link( 
		struct pipe_ctx *pipe_ctx)

{

	enum dc_status status = DC_ERROR_UNEXPECTED;

	struct dc_stream_state *stream = pipe_ctx->stream;

	struct dc_link *link = stream->link;



	/* There's some scenarios where driver is unloaded with display

	 * still enabled. When driver is reloaded, it may cause a display

	 * to not light up if there is a mismatch between old and new

	 * link settings. Need to call disable first before enabling at

	 * new link settings.

	 */

	if (link->link_status.link_active) {

		disable_link(link, pipe_ctx->stream->signal);

	}



	switch (pipe_ctx->stream->signal) {

	case SIGNAL_TYPE_DISPLAY_PORT:

		status = enable_link_dp(state, pipe_ctx);
@@ -2157,44 +2200,6 @@ static enum dc_status enable_link( 
	return status;

}



static void disable_link(struct dc_link *link, enum signal_type signal)

{

	/*

	 * TODO: implement call for dp_set_hw_test_pattern

	 * it is needed for compliance testing

	 */



	/* 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 (dc_is_dp_signal(signal)) {

		/* SST DP, eDP */

		if (dc_is_dp_sst_signal(signal))

			dp_disable_link_phy(link, signal);

		else

			dp_disable_link_phy_mst(link, signal);



		if (dc_is_dp_sst_signal(signal) ||

				link->mst_stream_alloc_table.stream_count == 0) {

			dp_set_fec_enable(link, false);

			dp_set_fec_ready(link, false);

		}

	} else {

		if (signal != SIGNAL_TYPE_VIRTUAL)

			link->link_enc->funcs->disable_output(link->link_enc, signal);

	}



	if (signal == SIGNAL_TYPE_DISPLAY_PORT_MST) {

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

		if (link->mst_stream_alloc_table.stream_count <= 0)

			link->link_status.link_active = false;

	} else {

		link->link_status.link_active = false;

	}

}



static uint32_t get_timing_pixel_clock_100hz(const struct dc_crtc_timing *timing)

{