drm/amd/display: Support long vblank feature

[WHY]
We want to support low hz case, but the original
vtotal/vtotal_min/vtotal_max can't support more
than 0x7FFF.

[HOW]
We use the 2 HW reg to contorl long vblank case.
1. OTG_V_COUNT_STOP_CONTROL -> vcount_stop
2. OTG_V_COUNT_STOP_CONTROL2 -> vcount_stop_timer

vcount_stop define from which line we stop using vcount
and start using vcount2.
vcount_stop_timer define how long we use vcount2.

Ex:
Vtotal = 7
OTG_V_COUNT_STOP_CONTROL = 4
OTG_V_COUNT_STOP_CONTROL2 = 5

time    : 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
vcount  : 0, 1, 2, 3, -  -  -  -  -  4,  5,  6
vcount2 :             0, 1, 2, 3, 4,
Reviewed-by: Jun Lei <jun.lei@amd.com>
Acked-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: ChunTao Tso <chuntao.tso@amd.com>
Signed-off-by: Robin Chen<robin.chen@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -386,6 +386,30 @@ static void dc_perf_trace_destroy(struct dc_perf_trace **perf_trace)
 	*perf_trace = NULL;
 }
 
+static bool set_long_vtotal(struct dc *dc, struct dc_stream_state *stream, struct dc_crtc_timing_adjust *adjust)
+{
+	if (!dc || !stream || !adjust)
+		return false;
+
+	if (!dc->current_state)
+		return false;
+
+	int i;
+
+	for (i = 0; i < MAX_PIPES; i++) {
+		struct pipe_ctx *pipe = &dc->current_state->res_ctx.pipe_ctx[i];
+
+		if (pipe->stream == stream && pipe->stream_res.tg) {
+			if (dc->hwss.set_long_vtotal)
+				dc->hwss.set_long_vtotal(&pipe, 1, adjust->v_total_min, adjust->v_total_max);
+
+			return true;
+		}
+	}
+
+	return false;
+}
+
 /**
  *  dc_stream_adjust_vmin_vmax - look up pipe context & update parts of DRR
  *  @dc:     dc reference
@@ -420,6 +444,15 @@ bool dc_stream_adjust_vmin_vmax(struct dc *dc,
 	stream->adjust.v_total_mid = adjust->v_total_mid;
 	stream->adjust.v_total_mid_frame_num = adjust->v_total_mid_frame_num;
 	stream->adjust.v_total_min = adjust->v_total_min;
+	stream->adjust.allow_otg_v_count_halt = adjust->allow_otg_v_count_halt;
+
+	if (dc->caps.max_v_total != 0 &&
+		(adjust->v_total_max > dc->caps.max_v_total || adjust->v_total_min > dc->caps.max_v_total)) {
+		if (adjust->allow_otg_v_count_halt)
+			return set_long_vtotal(dc, stream, adjust);
+		else
+			return false;
+	}
 
 	for (i = 0; i < MAX_PIPES; i++) {
 		struct pipe_ctx *pipe = &dc->current_state->res_ctx.pipe_ctx[i];

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

@@ -974,6 +974,7 @@ struct dc_crtc_timing_adjust {
 	uint32_t v_total_max;
 	uint32_t v_total_mid;
 	uint32_t v_total_mid_frame_num;
+	uint32_t allow_otg_v_count_halt;
 };
 
 

drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c

@@ -1394,3 +1394,31 @@ void dcn35_set_static_screen_control(struct pipe_ctx **pipe_ctx,
 			set_static_screen_control(pipe_ctx[i]->stream_res.tg,
 					triggers, params->num_frames);
 }
+
+void dcn35_set_long_vblank(struct pipe_ctx **pipe_ctx,
+		int num_pipes, uint32_t v_total_min, uint32_t v_total_max)
+{
+	int i = 0;
+	struct long_vtotal_params params = {0};
+
+	params.vertical_total_max = v_total_max;
+	params.vertical_total_min = v_total_min;
+
+	for (i = 0; i < num_pipes; i++) {
+		if (!pipe_ctx[i])
+			continue;
+
+		if (pipe_ctx[i]->stream) {
+			struct dc_crtc_timing *timing = &pipe_ctx[i]->stream->timing;
+
+			if (timing)
+				params.vertical_blank_start = timing->v_total - timing->v_front_porch;
+			else
+				params.vertical_blank_start = 0;
+
+			if ((pipe_ctx[i]->stream_res.tg != NULL) && pipe_ctx[i]->stream_res.tg->funcs &&
+				pipe_ctx[i]->stream_res.tg->funcs->set_long_vtotal)
+				pipe_ctx[i]->stream_res.tg->funcs->set_long_vtotal(pipe_ctx[i]->stream_res.tg, &params);
+		}
+	}
+}

drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.h

@@ -93,4 +93,7 @@ void dcn35_set_drr(struct pipe_ctx **pipe_ctx,
 void dcn35_set_static_screen_control(struct pipe_ctx **pipe_ctx,
 		int num_pipes, const struct dc_static_screen_params *params);
 
+void dcn35_set_long_vblank(struct pipe_ctx **pipe_ctx,
+		int num_pipes, uint32_t v_total_min, uint32_t v_total_max);
+
 #endif /* __DC_HWSS_DCN35_H__ */

drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_init.c

@@ -122,7 +122,8 @@ static const struct hw_sequencer_funcs dcn35_funcs = {
 	.hw_block_power_down = dcn35_hw_block_power_down,
 	.root_clock_control = dcn35_root_clock_control,
 	.set_idle_state = dcn35_set_idle_state,
-	.get_idle_state = dcn35_get_idle_state
+	.get_idle_state = dcn35_get_idle_state,
+	.set_long_vtotal = dcn35_set_long_vblank,
 };
 
 static const struct hwseq_private_funcs dcn35_private_funcs = {

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

@@ -429,6 +429,7 @@ struct hw_sequencer_funcs {
 	bool (*is_pipe_topology_transition_seamless)(struct dc *dc,
 			const struct dc_state *cur_ctx,
 			const struct dc_state *new_ctx);
+	void (*set_long_vtotal)(struct pipe_ctx **pipe_ctx, int num_pipes, uint32_t v_total_min, uint32_t v_total_max);
 };
 
 void color_space_to_black_color(

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

@@ -64,6 +64,12 @@ struct drr_params {
 	bool immediate_flip;
 };
 
+struct long_vtotal_params {
+	uint32_t vertical_total_min;
+	uint32_t vertical_total_max;
+	uint32_t vertical_blank_start;
+};
+
 #define LEFT_EYE_3D_PRIMARY_SURFACE 1
 #define RIGHT_EYE_3D_PRIMARY_SURFACE 0
 
@@ -331,6 +337,7 @@ struct timing_generator_funcs {
 
 	void (*init_odm)(struct timing_generator *tg);
 	void (*wait_drr_doublebuffer_pending_clear)(struct timing_generator *tg);
+	void (*set_long_vtotal)(struct timing_generator *optc, const struct long_vtotal_params *params);
 	void (*wait_odm_doublebuffer_pending_clear)(struct timing_generator *tg);
 };
 

drivers/gpu/drm/amd/display/dc/optc/dcn10/dcn10_optc.h

@@ -129,6 +129,8 @@ struct dcn_optc_registers {
 	uint32_t OTG_V_TOTAL_MID;
 	uint32_t OTG_V_TOTAL_MIN;
 	uint32_t OTG_V_TOTAL_CONTROL;
+	uint32_t OTG_V_COUNT_STOP_CONTROL;
+	uint32_t OTG_V_COUNT_STOP_CONTROL2;
 	uint32_t OTG_TRIGA_CNTL;
 	uint32_t OTG_TRIGA_MANUAL_TRIG;
 	uint32_t OTG_MANUAL_FLOW_CONTROL;
@@ -581,7 +583,9 @@ struct dcn_optc_registers {
 	type OTG_CRC1_WINDOWB_X_END_READBACK;\
 	type OTG_CRC1_WINDOWB_Y_START_READBACK;\
 	type OTG_CRC1_WINDOWB_Y_END_READBACK;\
-	type OPTC_FGCG_REP_DIS;
+	type OPTC_FGCG_REP_DIS;\
+	type OTG_V_COUNT_STOP;\
+	type OTG_V_COUNT_STOP_TIMER;
 
 struct dcn_optc_shift {
 	TG_REG_FIELD_LIST(uint8_t)

drivers/gpu/drm/amd/display/dc/optc/dcn35/dcn35_optc.c

@@ -32,6 +32,7 @@
 #include "reg_helper.h"
 #include "dc.h"
 #include "dcn_calc_math.h"
+#include "dc_dmub_srv.h"
 
 #define REG(reg)\
 	optc1->tg_regs->reg
@@ -213,6 +214,167 @@ static bool optc35_configure_crc(struct timing_generator *optc,
 	return true;
 }
 
+static void optc35_setup_manual_trigger(struct timing_generator *optc)
+{
+	if (!optc || !optc->ctx)
+		return;
+
+	struct optc *optc1 = DCN10TG_FROM_TG(optc);
+	struct dc *dc = optc->ctx->dc;
+
+	if (dc->caps.dmub_caps.mclk_sw && !dc->debug.disable_fams)
+		dc_dmub_srv_set_drr_manual_trigger_cmd(dc, optc->inst);
+	else {
+		/*
+		 * MIN_MASK_EN is gone and MASK is now always enabled.
+		 *
+		 * To get it to it work with manual trigger we need to make sure
+		 * we program the correct bit.
+		 */
+		REG_UPDATE_4(OTG_V_TOTAL_CONTROL,
+				OTG_V_TOTAL_MIN_SEL, 1,
+				OTG_V_TOTAL_MAX_SEL, 1,
+				OTG_FORCE_LOCK_ON_EVENT, 0,
+				OTG_SET_V_TOTAL_MIN_MASK, (1 << 1)); /* TRIGA */
+
+		// Setup manual flow control for EOF via TRIG_A
+		if (optc->funcs && optc->funcs->setup_manual_trigger)
+			optc->funcs->setup_manual_trigger(optc);
+	}
+}
+
+void optc35_set_drr(
+	struct timing_generator *optc,
+	const struct drr_params *params)
+{
+	if (!optc || !params)
+		return;
+
+	struct optc *optc1 = DCN10TG_FROM_TG(optc);
+	uint32_t max_otg_v_total = optc1->max_v_total - 1;
+
+	if (params != NULL &&
+		params->vertical_total_max > 0 &&
+		params->vertical_total_min > 0) {
+
+		if (params->vertical_total_mid != 0) {
+
+			REG_SET(OTG_V_TOTAL_MID, 0,
+				OTG_V_TOTAL_MID, params->vertical_total_mid - 1);
+
+			REG_UPDATE_2(OTG_V_TOTAL_CONTROL,
+					OTG_VTOTAL_MID_REPLACING_MAX_EN, 1,
+					OTG_VTOTAL_MID_FRAME_NUM,
+					(uint8_t)params->vertical_total_mid_frame_num);
+
+		}
+
+		if (optc->funcs && optc->funcs->set_vtotal_min_max)
+			optc->funcs->set_vtotal_min_max(optc,
+				params->vertical_total_min - 1, params->vertical_total_max - 1);
+		optc35_setup_manual_trigger(optc);
+	} else {
+		REG_UPDATE_4(OTG_V_TOTAL_CONTROL,
+				OTG_SET_V_TOTAL_MIN_MASK, 0,
+				OTG_V_TOTAL_MIN_SEL, 0,
+				OTG_V_TOTAL_MAX_SEL, 0,
+				OTG_FORCE_LOCK_ON_EVENT, 0);
+
+		if (optc->funcs && optc->funcs->set_vtotal_min_max)
+			optc->funcs->set_vtotal_min_max(optc, 0, 0);
+	}
+
+	REG_WRITE(OTG_V_COUNT_STOP_CONTROL, max_otg_v_total);
+	REG_WRITE(OTG_V_COUNT_STOP_CONTROL2, 0);
+}
+
+static void optc35_set_long_vtotal(
+	struct timing_generator *optc,
+	const struct long_vtotal_params *params)
+{
+	if (!optc || !params)
+		return;
+
+	struct optc *optc1 = DCN10TG_FROM_TG(optc);
+	uint32_t vcount_stop_timer = 0, vcount_stop = 0;
+	uint32_t max_otg_v_total = optc1->max_v_total - 1;
+
+	if (params->vertical_total_min <= max_otg_v_total && params->vertical_total_max <= max_otg_v_total)
+		return;
+
+	if (params->vertical_total_max == 0 || params->vertical_total_min == 0) {
+		REG_UPDATE_4(OTG_V_TOTAL_CONTROL,
+						OTG_SET_V_TOTAL_MIN_MASK, 0,
+						OTG_V_TOTAL_MIN_SEL, 0,
+						OTG_V_TOTAL_MAX_SEL, 0,
+						OTG_FORCE_LOCK_ON_EVENT, 0);
+
+		if (optc->funcs && optc->funcs->set_vtotal_min_max)
+			optc->funcs->set_vtotal_min_max(optc, 0, 0);
+	} else if (params->vertical_total_max == params->vertical_total_min) {
+		vcount_stop = params->vertical_blank_start;
+		vcount_stop_timer = params->vertical_total_max - max_otg_v_total;
+
+		REG_UPDATE_4(OTG_V_TOTAL_CONTROL,
+				OTG_V_TOTAL_MIN_SEL, 1,
+				OTG_V_TOTAL_MAX_SEL, 1,
+				OTG_FORCE_LOCK_ON_EVENT, 0,
+				OTG_SET_V_TOTAL_MIN_MASK, 0);
+
+		if (optc->funcs && optc->funcs->set_vtotal_min_max)
+			optc->funcs->set_vtotal_min_max(optc, max_otg_v_total, max_otg_v_total);
+
+		REG_WRITE(OTG_V_COUNT_STOP_CONTROL, vcount_stop);
+		REG_WRITE(OTG_V_COUNT_STOP_CONTROL2, vcount_stop_timer);
+	} else {
+		// Variable rate, keep DRR trigger mask
+		if (params->vertical_total_min > max_otg_v_total) {
+			// cannot be supported
+			// If MAX_OTG_V_COUNT < DRR trigger < v_total_min < v_total_max,
+			// DRR trigger will drop the vtotal counting directly to a new frame.
+			// But it should trigger between v_total_min and v_total_max.
+			ASSERT(0);
+
+			REG_UPDATE_4(OTG_V_TOTAL_CONTROL,
+				OTG_SET_V_TOTAL_MIN_MASK, 0,
+				OTG_V_TOTAL_MIN_SEL, 0,
+				OTG_V_TOTAL_MAX_SEL, 0,
+				OTG_FORCE_LOCK_ON_EVENT, 0);
+
+			if (optc->funcs && optc->funcs->set_vtotal_min_max)
+				optc->funcs->set_vtotal_min_max(optc, 0, 0);
+
+			REG_WRITE(OTG_V_COUNT_STOP_CONTROL, max_otg_v_total);
+			REG_WRITE(OTG_V_COUNT_STOP_CONTROL2, 0);
+		} else {
+			// For total_min <= MAX_OTG_V_COUNT and total_max > MAX_OTG_V_COUNT
+			vcount_stop = params->vertical_total_min;
+			vcount_stop_timer = params->vertical_total_max - max_otg_v_total;
+
+			// Example:
+			// params->vertical_total_min 1000
+			// params->vertical_total_max 2000
+			// MAX_OTG_V_COUNT_STOP = 1500
+			//
+			// If DRR event not happened,
+			//     time     0,1,2,3,4,...1000,1001,........,1500,1501,1502,     ...1999
+			//     vcount   0,1,2,3,4....1000...................,1001,1002,1003,...1399
+			//     vcount2                       0,1,2,3,4,..499,
+			// else (DRR event happened, ex : at line 1004)
+			//     time    0,1,2,3,4,...1000,1001.....1004, 0
+			//     vcount  0,1,2,3,4....1000,.............. 0 (new frame)
+			//     vcount2                      0,1,2,   3, -
+			if (optc->funcs && optc->funcs->set_vtotal_min_max)
+				optc->funcs->set_vtotal_min_max(optc,
+					params->vertical_total_min - 1, max_otg_v_total);
+			optc35_setup_manual_trigger(optc);
+
+			REG_WRITE(OTG_V_COUNT_STOP_CONTROL, vcount_stop);
+			REG_WRITE(OTG_V_COUNT_STOP_CONTROL2, vcount_stop_timer);
+		}
+	}
+}
+
 static struct timing_generator_funcs dcn35_tg_funcs = {
 		.validate_timing = optc1_validate_timing,
 		.program_timing = optc1_program_timing,
@@ -245,7 +407,7 @@ static struct timing_generator_funcs dcn35_tg_funcs = {
 		.lock_doublebuffer_enable = optc3_lock_doublebuffer_enable,
 		.lock_doublebuffer_disable = optc3_lock_doublebuffer_disable,
 		.enable_optc_clock = optc1_enable_optc_clock,
-		.set_drr = optc31_set_drr,
+		.set_drr = optc35_set_drr,
 		.get_last_used_drr_vtotal = optc2_get_last_used_drr_vtotal,
 		.set_vtotal_min_max = optc1_set_vtotal_min_max,
 		.set_static_screen_control = optc1_set_static_screen_control,
@@ -275,6 +437,7 @@ static struct timing_generator_funcs dcn35_tg_funcs = {
 		.setup_manual_trigger = optc2_setup_manual_trigger,
 		.get_hw_timing = optc1_get_hw_timing,
 		.init_odm = optc3_init_odm,
+		.set_long_vtotal = optc35_set_long_vtotal,
 };
 
 void dcn35_timing_generator_init(struct optc *optc1)

drivers/gpu/drm/amd/display/dc/optc/dcn35/dcn35_optc.h

@@ -65,10 +65,14 @@
 	SF(OTG0_OTG_CRC1_WINDOWB_X_CONTROL_READBACK, OTG_CRC1_WINDOWB_X_END_READBACK, mask_sh),\
 	SF(OTG0_OTG_CRC1_WINDOWB_Y_CONTROL_READBACK, OTG_CRC1_WINDOWB_Y_START_READBACK, mask_sh),\
 	SF(OTG0_OTG_CRC1_WINDOWB_Y_CONTROL_READBACK, OTG_CRC1_WINDOWB_Y_END_READBACK, mask_sh),\
-	SF(OPTC_CLOCK_CONTROL, OPTC_FGCG_REP_DIS, mask_sh)
+	SF(OPTC_CLOCK_CONTROL, OPTC_FGCG_REP_DIS, mask_sh),\
+	SF(OTG0_OTG_V_COUNT_STOP_CONTROL, OTG_V_COUNT_STOP, mask_sh),\
+	SF(OTG0_OTG_V_COUNT_STOP_CONTROL2, OTG_V_COUNT_STOP_TIMER, mask_sh)
 
 void dcn35_timing_generator_init(struct optc *optc1);
 
 void dcn35_timing_generator_set_fgcg(struct optc *optc1, bool enable);
 
+void optc35_set_drr(struct timing_generator *optc, const struct drr_params *params);
+
 #endif /* __DC_OPTC_DCN35_H__ */

drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.h

@@ -240,6 +240,8 @@ struct resource_pool *dcn35_create_resource_pool(
 	SRI_ARR(OTG_V_TOTAL_MAX, OTG, inst),\
 	SRI_ARR(OTG_V_TOTAL_MIN, OTG, inst),\
 	SRI_ARR(OTG_V_TOTAL_CONTROL, OTG, inst),\
+	SRI_ARR(OTG_V_COUNT_STOP_CONTROL, OTG, inst),\
+	SRI_ARR(OTG_V_COUNT_STOP_CONTROL2, OTG, inst),\
 	SRI_ARR(OTG_TRIGA_CNTL, OTG, inst),\
 	SRI_ARR(OTG_FORCE_COUNT_NOW_CNTL, OTG, inst),\
 	SRI_ARR(OTG_STATIC_SCREEN_CONTROL, OTG, inst),\

drivers/gpu/drm/amd/display/modules/freesync/freesync.c

@@ -1126,6 +1126,8 @@ void mod_freesync_build_vrr_params(struct mod_freesync *mod_freesync,
 		in_out_vrr->adjust.v_total_min = stream->timing.v_total;
 		in_out_vrr->adjust.v_total_max = stream->timing.v_total;
 	}
+
+	in_out_vrr->adjust.allow_otg_v_count_halt = (in_config->state == VRR_STATE_ACTIVE_FIXED) ? true : false;
 }
 
 void mod_freesync_handle_preflip(struct mod_freesync *mod_freesync,