drm/amd/display: Multi display synchronization logic

This feature synchronizes multiple displays with various timings
to a display with the highest refresh rate
it is enabled if edid caps flag multi_display_sync is set to one

There are limitations on refresh rates allowed
that can be synchronized. That would
prevent from underflow and other potential
corruptions.

Multi display synchronization is using the
same functions as timing_sync in order to minimize
redunduncy and decision to disable synchronization is
based on trigger parametre set in DM

Feature is developed for DCN1 and DCE11
Signed-off-by: NMikita Lipski <mikita.lipski@amd.com>
Reviewed-by: NMikita Lipski <Mikita.Lipski@amd.com>
Acked-by: NHarry Wentland <harry.wentland@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

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

@@ -2298,6 +2298,56 @@ static int create_fake_sink(struct amdgpu_dm_connector *aconnector)
 	return 0;
 }
 
+static void set_multisync_trigger_params(
+		struct dc_stream_state *stream)
+{
+	if (stream->triggered_crtc_reset.enabled) {
+		stream->triggered_crtc_reset.event = CRTC_EVENT_VSYNC_RISING;
+		stream->triggered_crtc_reset.delay = TRIGGER_DELAY_NEXT_LINE;
+	}
+}
+
+static void set_master_stream(struct dc_stream_state *stream_set[],
+			      int stream_count)
+{
+	int j, highest_rfr = 0, master_stream = 0;
+
+	for (j = 0;  j < stream_count; j++) {
+		if (stream_set[j] && stream_set[j]->triggered_crtc_reset.enabled) {
+			int refresh_rate = 0;
+
+			refresh_rate = (stream_set[j]->timing.pix_clk_khz*1000)/
+				(stream_set[j]->timing.h_total*stream_set[j]->timing.v_total);
+			if (refresh_rate > highest_rfr) {
+				highest_rfr = refresh_rate;
+				master_stream = j;
+			}
+		}
+	}
+	for (j = 0;  j < stream_count; j++) {
+		if (stream_set[j] && j != master_stream)
+			stream_set[j]->triggered_crtc_reset.event_source = stream_set[master_stream];
+	}
+}
+
+static void dm_enable_per_frame_crtc_master_sync(struct dc_state *context)
+{
+	int i = 0;
+
+	if (context->stream_count < 2)
+		return;
+	for (i = 0; i < context->stream_count ; i++) {
+		if (!context->streams[i])
+			continue;
+		/* TODO: add a function to read AMD VSDB bits and will set
+		 * crtc_sync_master.multi_sync_enabled flag
+		 * For now its set to false
+		 */
+		set_multisync_trigger_params(context->streams[i]);
+	}
+	set_master_stream(context->streams, context->stream_count);
+}
+
 static struct dc_stream_state *
 create_stream_for_sink(struct amdgpu_dm_connector *aconnector,
 		       const struct drm_display_mode *drm_mode,
@@ -4132,8 +4182,10 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
 		}
 	}
 
-	if (dm_state->context)
+	if (dm_state->context) {
+		dm_enable_per_frame_crtc_master_sync(dm_state->context);
 		WARN_ON(!dc_commit_state(dm->dc, dm_state->context));
+	}
 
 	for_each_new_crtc_in_state(state, crtc, new_crtc_state, i) {
 		struct amdgpu_crtc *acrtc = to_amdgpu_crtc(crtc);

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

@@ -713,6 +713,28 @@ void dc_destroy(struct dc **dc)
 	*dc = NULL;
 }
 
+static void enable_timing_multisync(
+		struct dc *dc,
+		struct dc_state *ctx)
+{
+	int i = 0, multisync_count = 0;
+	int pipe_count = dc->res_pool->pipe_count;
+	struct pipe_ctx *multisync_pipes[MAX_PIPES] = { NULL };
+
+	for (i = 0; i < pipe_count; i++) {
+		if (!ctx->res_ctx.pipe_ctx[i].stream ||
+				!ctx->res_ctx.pipe_ctx[i].stream->triggered_crtc_reset.enabled)
+			continue;
+		multisync_pipes[multisync_count] = &ctx->res_ctx.pipe_ctx[i];
+		multisync_count++;
+	}
+
+	if (multisync_count > 1) {
+		dc->hwss.enable_per_frame_crtc_position_reset(
+			dc, multisync_count, multisync_pipes);
+	}
+}
+
 static void program_timing_sync(
 		struct dc *dc,
 		struct dc_state *ctx)
@@ -891,7 +913,9 @@ static enum dc_status dc_commit_state_no_check(struct dc *dc, struct dc_state *c
 	}
 	result = dc->hwss.apply_ctx_to_hw(dc, context);
 
-	program_timing_sync(dc, context);
+	if (context->stream_count > 1)
+		enable_timing_multisync(dc, context);
+		program_timing_sync(dc, context);
 
 	dc_enable_stereo(dc, context, dc_streams, context->stream_count);
 

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

@@ -607,6 +607,9 @@ struct dc_stream_state {
 
 	/* from stream struct */
 	struct kref refcount;
+
+	struct crtc_trigger_info triggered_crtc_reset;
+
 };
 
 struct dc_stream_update {

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

@@ -673,6 +673,22 @@ enum dc_timing_3d_format {
 	TIMING_3D_FORMAT_MAX,
 };
 
+enum trigger_delay {
+	TRIGGER_DELAY_NEXT_PIXEL = 0,
+	TRIGGER_DELAY_NEXT_LINE,
+};
+
+enum crtc_event {
+	CRTC_EVENT_VSYNC_RISING = 0,
+	CRTC_EVENT_VSYNC_FALLING
+};
+
+struct crtc_trigger_info {
+	bool enabled;
+	struct dc_stream_state *event_source;
+	enum crtc_event event;
+	enum trigger_delay delay;
+};
 
 struct dc_crtc_timing {
 

drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c

@@ -2457,20 +2457,16 @@ static void dce110_enable_timing_synchronization(
 
 	for (i = 1 /* skip the master */; i < group_size; i++)
 		grouped_pipes[i]->stream_res.tg->funcs->enable_reset_trigger(
-					grouped_pipes[i]->stream_res.tg, gsl_params.gsl_group);
-
-
+				grouped_pipes[i]->stream_res.tg,
+				gsl_params.gsl_group);
 
 	for (i = 1 /* skip the master */; i < group_size; i++) {
 		DC_SYNC_INFO("GSL: waiting for reset to occur.\n");
 		wait_for_reset_trigger_to_occur(dc_ctx, grouped_pipes[i]->stream_res.tg);
-		/* Regardless of success of the wait above, remove the reset or
-		 * the driver will start timing out on Display requests. */
-		DC_SYNC_INFO("GSL: disabling trigger-reset.\n");
-		grouped_pipes[i]->stream_res.tg->funcs->disable_reset_trigger(grouped_pipes[i]->stream_res.tg);
+		grouped_pipes[i]->stream_res.tg->funcs->disable_reset_trigger(
+				grouped_pipes[i]->stream_res.tg);
 	}
 
-
 	/* GSL Vblank synchronization is a one time sync mechanism, assumption
 	 * is that the sync'ed displays will not drift out of sync over time*/
 	DC_SYNC_INFO("GSL: Restoring register states.\n");
@@ -2480,6 +2476,39 @@ static void dce110_enable_timing_synchronization(
 	DC_SYNC_INFO("GSL: Set-up complete.\n");
 }
 
+static void dce110_enable_per_frame_crtc_position_reset(
+		struct dc *dc,
+		int group_size,
+		struct pipe_ctx *grouped_pipes[])
+{
+	struct dc_context *dc_ctx = dc->ctx;
+	struct dcp_gsl_params gsl_params = { 0 };
+	int i;
+
+	gsl_params.gsl_group = 0;
+	gsl_params.gsl_master = grouped_pipes[0]->stream->triggered_crtc_reset.event_source->status.primary_otg_inst;
+
+	for (i = 0; i < group_size; i++)
+		grouped_pipes[i]->stream_res.tg->funcs->setup_global_swap_lock(
+					grouped_pipes[i]->stream_res.tg, &gsl_params);
+
+	DC_SYNC_INFO("GSL: enabling trigger-reset\n");
+
+	for (i = 1; i < group_size; i++)
+		grouped_pipes[i]->stream_res.tg->funcs->enable_crtc_reset(
+				grouped_pipes[i]->stream_res.tg,
+				gsl_params.gsl_master,
+				&grouped_pipes[i]->stream->triggered_crtc_reset);
+
+	DC_SYNC_INFO("GSL: waiting for reset to occur.\n");
+	for (i = 1; i < group_size; i++)
+		wait_for_reset_trigger_to_occur(dc_ctx, grouped_pipes[i]->stream_res.tg);
+
+	for (i = 0; i < group_size; i++)
+		grouped_pipes[i]->stream_res.tg->funcs->tear_down_global_swap_lock(grouped_pipes[i]->stream_res.tg);
+
+}
+
 static void init_hw(struct dc *dc)
 {
 	int i;
@@ -2976,6 +3005,7 @@ static const struct hw_sequencer_funcs dce110_funcs = {
 	.power_down = dce110_power_down,
 	.enable_accelerated_mode = dce110_enable_accelerated_mode,
 	.enable_timing_synchronization = dce110_enable_timing_synchronization,
+	.enable_per_frame_crtc_position_reset = dce110_enable_per_frame_crtc_position_reset,
 	.update_info_frame = dce110_update_info_frame,
 	.enable_stream = dce110_enable_stream,
 	.disable_stream = dce110_disable_stream,

drivers/gpu/drm/amd/display/dc/dce110/dce110_timing_generator.c

@@ -1224,26 +1224,46 @@ void dce110_timing_generator_setup_global_swap_lock(
 
 	/* This pipe will belong to GSL Group zero. */
 	set_reg_field_value(value,
-			1,
-			DCP_GSL_CONTROL,
-			DCP_GSL0_EN);
+			    1,
+			    DCP_GSL_CONTROL,
+			    DCP_GSL0_EN);
 
 	set_reg_field_value(value,
-			gsl_params->gsl_master == tg->inst,
-			DCP_GSL_CONTROL,
-			DCP_GSL_MASTER_EN);
+			    gsl_params->gsl_master == tg->inst,
+			    DCP_GSL_CONTROL,
+			    DCP_GSL_MASTER_EN);
 
 	set_reg_field_value(value,
-			HFLIP_READY_DELAY,
-			DCP_GSL_CONTROL,
-			DCP_GSL_HSYNC_FLIP_FORCE_DELAY);
+			    HFLIP_READY_DELAY,
+			    DCP_GSL_CONTROL,
+			    DCP_GSL_HSYNC_FLIP_FORCE_DELAY);
 
 	/* Keep signal low (pending high) during 6 lines.
 	 * Also defines minimum interval before re-checking signal. */
 	set_reg_field_value(value,
-			HFLIP_CHECK_DELAY,
-			DCP_GSL_CONTROL,
-			DCP_GSL_HSYNC_FLIP_CHECK_DELAY);
+			    HFLIP_CHECK_DELAY,
+			    DCP_GSL_CONTROL,
+			    DCP_GSL_HSYNC_FLIP_CHECK_DELAY);
+
+	dm_write_reg(tg->ctx, CRTC_REG(mmDCP_GSL_CONTROL), value);
+	value = 0;
+
+	set_reg_field_value(value,
+			    gsl_params->gsl_master,
+			    DCIO_GSL0_CNTL,
+			    DCIO_GSL0_VSYNC_SEL);
+
+	set_reg_field_value(value,
+			    0,
+			    DCIO_GSL0_CNTL,
+			    DCIO_GSL0_TIMING_SYNC_SEL);
+
+	set_reg_field_value(value,
+			    0,
+			    DCIO_GSL0_CNTL,
+			    DCIO_GSL0_GLOBAL_UNLOCK_SEL);
+
+	dm_write_reg(tg->ctx, CRTC_REG(mmDCIO_GSL0_CNTL), value);
 
 
 	{
@@ -1253,38 +1273,38 @@ void dce110_timing_generator_setup_global_swap_lock(
 				CRTC_REG(mmCRTC_V_TOTAL));
 
 		set_reg_field_value(value,
-				0,/* DCP_GSL_PURPOSE_SURFACE_FLIP */
-				DCP_GSL_CONTROL,
-				DCP_GSL_SYNC_SOURCE);
+				    0,/* DCP_GSL_PURPOSE_SURFACE_FLIP */
+				    DCP_GSL_CONTROL,
+				    DCP_GSL_SYNC_SOURCE);
 
 		/* Checkpoint relative to end of frame */
 		check_point = get_reg_field_value(value_crtc_vtotal,
-				CRTC_V_TOTAL,
-				CRTC_V_TOTAL);
+						  CRTC_V_TOTAL,
+						  CRTC_V_TOTAL);
 
 		dm_write_reg(tg->ctx, CRTC_REG(mmCRTC_GSL_WINDOW), 0);
 	}
 
 	set_reg_field_value(value,
-			1,
-			DCP_GSL_CONTROL,
-			DCP_GSL_DELAY_SURFACE_UPDATE_PENDING);
+			    1,
+			    DCP_GSL_CONTROL,
+			    DCP_GSL_DELAY_SURFACE_UPDATE_PENDING);
 
 	dm_write_reg(tg->ctx, address, value);
 
 	/********************************************************************/
 	address = CRTC_REG(mmCRTC_GSL_CONTROL);
 
-	value = 0;
+	value = dm_read_reg(tg->ctx, address);
 	set_reg_field_value(value,
-			check_point - FLIP_READY_BACK_LOOKUP,
-			CRTC_GSL_CONTROL,
-			CRTC_GSL_CHECK_LINE_NUM);
+			    check_point - FLIP_READY_BACK_LOOKUP,
+			    CRTC_GSL_CONTROL,
+			    CRTC_GSL_CHECK_LINE_NUM);
 
 	set_reg_field_value(value,
-			VFLIP_READY_DELAY,
-			CRTC_GSL_CONTROL,
-			CRTC_GSL_FORCE_DELAY);
+			    VFLIP_READY_DELAY,
+			    CRTC_GSL_CONTROL,
+			    CRTC_GSL_FORCE_DELAY);
 
 	dm_write_reg(tg->ctx, address, value);
 }
@@ -1555,6 +1575,138 @@ void dce110_timing_generator_enable_reset_trigger(
 	dm_write_reg(tg->ctx, CRTC_REG(mmCRTC_FORCE_COUNT_NOW_CNTL), value);
 }
 
+void dce110_timing_generator_enable_crtc_reset(
+		struct timing_generator *tg,
+		int source_tg_inst,
+		struct crtc_trigger_info *crtc_tp)
+{
+	uint32_t value = 0;
+	uint32_t rising_edge = 0;
+	uint32_t falling_edge = 0;
+	struct dce110_timing_generator *tg110 = DCE110TG_FROM_TG(tg);
+
+	/* Setup trigger edge */
+	switch (crtc_tp->event) {
+	case CRTC_EVENT_VSYNC_RISING:
+			rising_edge = 1;
+			break;
+
+	case CRTC_EVENT_VSYNC_FALLING:
+		falling_edge = 1;
+		break;
+	}
+
+	value = dm_read_reg(tg->ctx, CRTC_REG(mmCRTC_TRIGB_CNTL));
+
+	set_reg_field_value(value,
+			    source_tg_inst,
+			    CRTC_TRIGB_CNTL,
+			    CRTC_TRIGB_SOURCE_SELECT);
+
+	set_reg_field_value(value,
+			    TRIGGER_POLARITY_SELECT_LOGIC_ZERO,
+			    CRTC_TRIGB_CNTL,
+			    CRTC_TRIGB_POLARITY_SELECT);
+
+	set_reg_field_value(value,
+			    rising_edge,
+			    CRTC_TRIGB_CNTL,
+			    CRTC_TRIGB_RISING_EDGE_DETECT_CNTL);
+
+	set_reg_field_value(value,
+			    falling_edge,
+			    CRTC_TRIGB_CNTL,
+			    CRTC_TRIGB_FALLING_EDGE_DETECT_CNTL);
+
+	set_reg_field_value(value,
+			    1, /* clear trigger status */
+			    CRTC_TRIGB_CNTL,
+			    CRTC_TRIGB_CLEAR);
+
+	dm_write_reg(tg->ctx, CRTC_REG(mmCRTC_TRIGB_CNTL), value);
+
+	/**************************************************************/
+
+	switch (crtc_tp->delay) {
+	case TRIGGER_DELAY_NEXT_LINE:
+		value = dm_read_reg(tg->ctx, CRTC_REG(mmCRTC_FORCE_COUNT_NOW_CNTL));
+
+		set_reg_field_value(value,
+				    0, /* force H count to H_TOTAL and V count to V_TOTAL */
+				    CRTC_FORCE_COUNT_NOW_CNTL,
+				    CRTC_FORCE_COUNT_NOW_MODE);
+
+		set_reg_field_value(value,
+				    0, /* TriggerB - we never use TriggerA */
+				    CRTC_FORCE_COUNT_NOW_CNTL,
+				    CRTC_FORCE_COUNT_NOW_TRIG_SEL);
+
+		set_reg_field_value(value,
+				    1, /* clear trigger status */
+				    CRTC_FORCE_COUNT_NOW_CNTL,
+				    CRTC_FORCE_COUNT_NOW_CLEAR);
+
+		dm_write_reg(tg->ctx, CRTC_REG(mmCRTC_FORCE_COUNT_NOW_CNTL), value);
+
+		value = dm_read_reg(tg->ctx, CRTC_REG(mmCRTC_VERT_SYNC_CONTROL));
+
+		set_reg_field_value(value,
+				    1,
+				    CRTC_VERT_SYNC_CONTROL,
+				    CRTC_FORCE_VSYNC_NEXT_LINE_CLEAR);
+
+		set_reg_field_value(value,
+				    2,
+				    CRTC_VERT_SYNC_CONTROL,
+				    CRTC_AUTO_FORCE_VSYNC_MODE);
+
+		break;
+
+	case TRIGGER_DELAY_NEXT_PIXEL:
+		value = dm_read_reg(tg->ctx, CRTC_REG(mmCRTC_VERT_SYNC_CONTROL));
+
+		set_reg_field_value(value,
+				    1,
+				    CRTC_VERT_SYNC_CONTROL,
+				    CRTC_FORCE_VSYNC_NEXT_LINE_CLEAR);
+
+		set_reg_field_value(value,
+				    0,
+				    CRTC_VERT_SYNC_CONTROL,
+				    CRTC_AUTO_FORCE_VSYNC_MODE);
+
+		dm_write_reg(tg->ctx, CRTC_REG(mmCRTC_VERT_SYNC_CONTROL), value);
+
+		value = dm_read_reg(tg->ctx, CRTC_REG(mmCRTC_FORCE_COUNT_NOW_CNTL));
+
+		set_reg_field_value(value,
+				    2, /* force H count to H_TOTAL and V count to V_TOTAL */
+				    CRTC_FORCE_COUNT_NOW_CNTL,
+				    CRTC_FORCE_COUNT_NOW_MODE);
+
+		set_reg_field_value(value,
+				    1, /* TriggerB - we never use TriggerA */
+				    CRTC_FORCE_COUNT_NOW_CNTL,
+				    CRTC_FORCE_COUNT_NOW_TRIG_SEL);
+
+		set_reg_field_value(value,
+				    1, /* clear trigger status */
+				    CRTC_FORCE_COUNT_NOW_CNTL,
+				    CRTC_FORCE_COUNT_NOW_CLEAR);
+
+		dm_write_reg(tg->ctx, CRTC_REG(mmCRTC_FORCE_COUNT_NOW_CNTL), value);
+		break;
+	}
+
+	value = dm_read_reg(tg->ctx, CRTC_REG(mmCRTC_MASTER_UPDATE_MODE));
+
+	set_reg_field_value(value,
+			    2,
+			    CRTC_MASTER_UPDATE_MODE,
+			    MASTER_UPDATE_MODE);
+
+	dm_write_reg(tg->ctx, CRTC_REG(mmCRTC_MASTER_UPDATE_MODE), value);
+}
 void dce110_timing_generator_disable_reset_trigger(
 	struct timing_generator *tg)
 {
@@ -1564,34 +1716,48 @@ void dce110_timing_generator_disable_reset_trigger(
 	value = dm_read_reg(tg->ctx, CRTC_REG(mmCRTC_FORCE_COUNT_NOW_CNTL));
 
 	set_reg_field_value(value,
-			0, /* force counter now mode is disabled */
-			CRTC_FORCE_COUNT_NOW_CNTL,
-			CRTC_FORCE_COUNT_NOW_MODE);
+			    0, /* force counter now mode is disabled */
+			    CRTC_FORCE_COUNT_NOW_CNTL,
+			    CRTC_FORCE_COUNT_NOW_MODE);
 
 	set_reg_field_value(value,
-			1, /* clear trigger status */
-			CRTC_FORCE_COUNT_NOW_CNTL,
-			CRTC_FORCE_COUNT_NOW_CLEAR);
+			    1, /* clear trigger status */
+			    CRTC_FORCE_COUNT_NOW_CNTL,
+			    CRTC_FORCE_COUNT_NOW_CLEAR);
 
 	dm_write_reg(tg->ctx, CRTC_REG(mmCRTC_FORCE_COUNT_NOW_CNTL), value);
 
+	value = dm_read_reg(tg->ctx, CRTC_REG(mmCRTC_VERT_SYNC_CONTROL));
+
+	set_reg_field_value(value,
+			    1,
+			    CRTC_VERT_SYNC_CONTROL,
+			    CRTC_FORCE_VSYNC_NEXT_LINE_CLEAR);
+
+	set_reg_field_value(value,
+			    0,
+			    CRTC_VERT_SYNC_CONTROL,
+			    CRTC_AUTO_FORCE_VSYNC_MODE);
+
+	dm_write_reg(tg->ctx, CRTC_REG(mmCRTC_VERT_SYNC_CONTROL), value);
+
 	/********************************************************************/
 	value = dm_read_reg(tg->ctx, CRTC_REG(mmCRTC_TRIGB_CNTL));
 
 	set_reg_field_value(value,
-			TRIGGER_SOURCE_SELECT_LOGIC_ZERO,
-			CRTC_TRIGB_CNTL,
-			CRTC_TRIGB_SOURCE_SELECT);
+			    TRIGGER_SOURCE_SELECT_LOGIC_ZERO,
+			    CRTC_TRIGB_CNTL,
+			    CRTC_TRIGB_SOURCE_SELECT);
 
 	set_reg_field_value(value,
-			TRIGGER_POLARITY_SELECT_LOGIC_ZERO,
-			CRTC_TRIGB_CNTL,
-			CRTC_TRIGB_POLARITY_SELECT);
+			    TRIGGER_POLARITY_SELECT_LOGIC_ZERO,
+			    CRTC_TRIGB_CNTL,
+			    CRTC_TRIGB_POLARITY_SELECT);
 
 	set_reg_field_value(value,
-			1, /* clear trigger status */
-			CRTC_TRIGB_CNTL,
-			CRTC_TRIGB_CLEAR);
+			    1, /* clear trigger status */
+			    CRTC_TRIGB_CNTL,
+			    CRTC_TRIGB_CLEAR);
 
 	dm_write_reg(tg->ctx, CRTC_REG(mmCRTC_TRIGB_CNTL), value);
 }
@@ -1611,10 +1777,16 @@ bool dce110_timing_generator_did_triggered_reset_occur(
 	struct dce110_timing_generator *tg110 = DCE110TG_FROM_TG(tg);
 	uint32_t value = dm_read_reg(tg->ctx,
 			CRTC_REG(mmCRTC_FORCE_COUNT_NOW_CNTL));
-
-	return get_reg_field_value(value,
-			CRTC_FORCE_COUNT_NOW_CNTL,
-			CRTC_FORCE_COUNT_NOW_OCCURRED) != 0;
+	uint32_t value1 = dm_read_reg(tg->ctx,
+			CRTC_REG(mmCRTC_VERT_SYNC_CONTROL));
+	bool force = get_reg_field_value(value,
+					 CRTC_FORCE_COUNT_NOW_CNTL,
+					 CRTC_FORCE_COUNT_NOW_OCCURRED) != 0;
+	bool vert_sync = get_reg_field_value(value1,
+					     CRTC_VERT_SYNC_CONTROL,
+					     CRTC_FORCE_VSYNC_NEXT_LINE_OCCURRED) != 0;
+
+	return (force || vert_sync);
 }
 
 /**
@@ -1928,6 +2100,7 @@ static const struct timing_generator_funcs dce110_tg_funcs = {
 		.setup_global_swap_lock =
 				dce110_timing_generator_setup_global_swap_lock,
 		.enable_reset_trigger = dce110_timing_generator_enable_reset_trigger,
+		.enable_crtc_reset = dce110_timing_generator_enable_crtc_reset,
 		.disable_reset_trigger = dce110_timing_generator_disable_reset_trigger,
 		.tear_down_global_swap_lock =
 				dce110_timing_generator_tear_down_global_swap_lock,

drivers/gpu/drm/amd/display/dc/dce110/dce110_timing_generator.h

@@ -174,6 +174,12 @@ void dce110_timing_generator_setup_global_swap_lock(
 void dce110_timing_generator_tear_down_global_swap_lock(
 	struct timing_generator *tg);
 
+/* Reset crtc position on master VSync */
+void dce110_timing_generator_enable_crtc_reset(
+	struct timing_generator *tg,
+	int source,
+	struct crtc_trigger_info *crtc_tp);
+
 /* Reset slave controllers on master VSync */
 void dce110_timing_generator_enable_reset_trigger(
 	struct timing_generator *tg,

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c

@@ -1304,14 +1304,15 @@ static void dcn10_enable_timing_synchronization(
 
 	for (i = 1; i < group_size; i++)
 		grouped_pipes[i]->stream_res.tg->funcs->enable_reset_trigger(
-				grouped_pipes[i]->stream_res.tg, grouped_pipes[0]->stream_res.tg->inst);
-
+				grouped_pipes[i]->stream_res.tg,
+				grouped_pipes[0]->stream_res.tg->inst);
 
 	DC_SYNC_INFO("Waiting for trigger\n");
 
 	/* Need to get only check 1 pipe for having reset as all the others are
 	 * synchronized. Look at last pipe programmed to reset.
 	 */
+
 	wait_for_reset_trigger_to_occur(dc_ctx, grouped_pipes[1]->stream_res.tg);
 	for (i = 1; i < group_size; i++)
 		grouped_pipes[i]->stream_res.tg->funcs->disable_reset_trigger(
@@ -1320,6 +1321,29 @@ static void dcn10_enable_timing_synchronization(
 	DC_SYNC_INFO("Sync complete\n");
 }
 
+static void dcn10_enable_per_frame_crtc_position_reset(
+	struct dc *dc,
+	int group_size,
+	struct pipe_ctx *grouped_pipes[])
+{
+	struct dc_context *dc_ctx = dc->ctx;
+	int i;
+
+	DC_SYNC_INFO("Setting up\n");
+	for (i = 0; i < group_size; i++)
+		grouped_pipes[i]->stream_res.tg->funcs->enable_crtc_reset(
+				grouped_pipes[i]->stream_res.tg,
+				grouped_pipes[i]->stream->triggered_crtc_reset.event_source->status.primary_otg_inst,
+				&grouped_pipes[i]->stream->triggered_crtc_reset);
+
+	DC_SYNC_INFO("Waiting for trigger\n");
+
+	for (i = 1; i < group_size; i++)
+		wait_for_reset_trigger_to_occur(dc_ctx, grouped_pipes[i]->stream_res.tg);
+
+	DC_SYNC_INFO("Multi-display sync is complete\n");
+}
+
 static void print_rq_dlg_ttu(
 		struct dc *core_dc,
 		struct pipe_ctx *pipe_ctx)
@@ -2485,6 +2509,7 @@ static const struct hw_sequencer_funcs dcn10_funcs = {
 	.power_down = dce110_power_down,
 	.enable_accelerated_mode = dce110_enable_accelerated_mode,
 	.enable_timing_synchronization = dcn10_enable_timing_synchronization,
+	.enable_per_frame_crtc_position_reset = dcn10_enable_per_frame_crtc_position_reset,
 	.update_info_frame = dce110_update_info_frame,
 	.enable_stream = dce110_enable_stream,
 	.disable_stream = dce110_disable_stream,

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_timing_generator.c

@@ -610,12 +610,28 @@ static bool tgn10_did_triggered_reset_occur(
 	struct timing_generator *tg)
 {
 	struct dcn10_timing_generator *tgn10 = DCN10TG_FROM_TG(tg);
-	uint32_t occurred;
+	uint32_t occurred_force, occurred_vsync;
 
 	REG_GET(OTG_FORCE_COUNT_NOW_CNTL,
-		OTG_FORCE_COUNT_NOW_OCCURRED, &occurred);
+		OTG_FORCE_COUNT_NOW_OCCURRED, &occurred_force);
 
-	return occurred != 0;
+	REG_GET(OTG_VERT_SYNC_CONTROL,
+		OTG_FORCE_VSYNC_NEXT_LINE_OCCURRED, &occurred_vsync);
+
+	return occurred_vsync != 0 || occurred_force != 0;
+}
+
+static void tgn10_disable_reset_trigger(struct timing_generator *tg)
+{
+	struct dcn10_timing_generator *tgn10 = DCN10TG_FROM_TG(tg);
+
+	REG_WRITE(OTG_TRIGA_CNTL, 0);
+
+	REG_SET(OTG_FORCE_COUNT_NOW_CNTL, 0,
+		OTG_FORCE_COUNT_NOW_CLEAR, 1);
+
+	REG_SET(OTG_VERT_SYNC_CONTROL, 0,
+		OTG_FORCE_VSYNC_NEXT_LINE_CLEAR, 1);
 }
 
 static void tgn10_enable_reset_trigger(struct timing_generator *tg, int source_tg_inst)
@@ -652,14 +668,49 @@ static void tgn10_enable_reset_trigger(struct timing_generator *tg, int source_t
 			OTG_FORCE_COUNT_NOW_MODE, 2);
 }
 
-static void tgn10_disable_reset_trigger(struct timing_generator *tg)
+void tgn10_enable_crtc_reset(
+		struct timing_generator *tg,
+		int source_tg_inst,
+		struct crtc_trigger_info *crtc_tp)
 {
 	struct dcn10_timing_generator *tgn10 = DCN10TG_FROM_TG(tg);
+	uint32_t falling_edge = 0;
+	uint32_t rising_edge = 0;
 
-	REG_WRITE(OTG_TRIGA_CNTL, 0);
+	switch (crtc_tp->event) {
 
-	REG_SET(OTG_FORCE_COUNT_NOW_CNTL, 0,
-			OTG_FORCE_COUNT_NOW_CLEAR, 1);
+	case CRTC_EVENT_VSYNC_RISING:
+		rising_edge = 1;
+		break;
+
+	case CRTC_EVENT_VSYNC_FALLING:
+		falling_edge = 1;
+		break;
+	}
+
+	REG_SET_4(OTG_TRIGA_CNTL, 0,
+		 /* vsync signal from selected OTG pipe based
+		  * on OTG_TRIG_SOURCE_PIPE_SELECT setting
+		  */
+		  OTG_TRIGA_SOURCE_SELECT, 20,
+		  OTG_TRIGA_SOURCE_PIPE_SELECT, source_tg_inst,
+		  /* always detect falling edge */
+		  OTG_TRIGA_RISING_EDGE_DETECT_CNTL, rising_edge,
+		  OTG_TRIGA_FALLING_EDGE_DETECT_CNTL, falling_edge);
+
+	switch (crtc_tp->delay) {
+	case TRIGGER_DELAY_NEXT_LINE:
+		REG_SET(OTG_VERT_SYNC_CONTROL, 0,
+				OTG_AUTO_FORCE_VSYNC_MODE, 1);
+		break;
+	case TRIGGER_DELAY_NEXT_PIXEL:
+		REG_SET(OTG_FORCE_COUNT_NOW_CNTL, 0,
+			/* force H count to H_TOTAL and V count to V_TOTAL in
+			 * progressive mode and V_TOTAL-1 in interlaced mode
+			 */
+			OTG_FORCE_COUNT_NOW_MODE, 2);
+		break;
+	}
 }
 
 static void tgn10_wait_for_state(struct timing_generator *tg,
@@ -1174,6 +1225,7 @@ static const struct timing_generator_funcs dcn10_tg_funcs = {
 		.set_blank_color = tgn10_program_blank_color,
 		.did_triggered_reset_occur = tgn10_did_triggered_reset_occur,
 		.enable_reset_trigger = tgn10_enable_reset_trigger,
+		.enable_crtc_reset = tgn10_enable_crtc_reset,
 		.disable_reset_trigger = tgn10_disable_reset_trigger,
 		.lock = tgn10_lock,
 		.unlock = tgn10_unlock,

drivers/gpu/drm/amd/display/dc/inc/hw/timing_generator.h

@@ -158,7 +158,11 @@ struct timing_generator_funcs {
 							const struct dcp_gsl_params *gsl_params);
 	void (*unlock)(struct timing_generator *tg);
 	void (*lock)(struct timing_generator *tg);
-	void (*enable_reset_trigger)(struct timing_generator *tg, int source_tg_inst);
+	void (*enable_reset_trigger)(struct timing_generator *tg,
+				     int source_tg_inst);
+	void (*enable_crtc_reset)(struct timing_generator *tg,
+				  int source_tg_inst,
+				  struct crtc_trigger_info *crtc_tp);
 	void (*disable_reset_trigger)(struct timing_generator *tg);
 	void (*tear_down_global_swap_lock)(struct timing_generator *tg);
 	void (*enable_advanced_request)(struct timing_generator *tg,

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

@@ -114,6 +114,11 @@ struct hw_sequencer_funcs {
 			int group_size,
 			struct pipe_ctx *grouped_pipes[]);
 
+	void (*enable_per_frame_crtc_position_reset)(
+			struct dc *dc,
+			int group_size,
+			struct pipe_ctx *grouped_pipes[]);
+
 	void (*enable_display_pipe_clock_gating)(
 					struct dc_context *ctx,
 					bool clock_gating);