drm/amd/display: interface to check if timing can be seamless

[Why]
Need to figure out whether a timing we want to commit matches
something that GOP already programmed, in which case
we can decide to some optimizations

[How]
1. Add way to check for DIG FE
2. Add way to check for matching OTG timing
3. Add way to check for matching pixel clock (if possible)
    - Currently only support DP for pixel clock, since it is easy to calc

Signed-off-by: Anthony Koo <Anthony.Koo@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -969,6 +969,52 @@ static bool context_changed(
 	return false;
 }
 
+bool dc_validate_seamless_boot_timing(struct dc *dc,
+				const struct dc_sink *sink,
+				struct dc_crtc_timing *crtc_timing)
+{
+	struct timing_generator *tg;
+	struct dc_link *link = sink->link;
+	unsigned int inst;
+
+	/* Check for enabled DIG to identify enabled display */
+	if (!link->link_enc->funcs->is_dig_enabled(link->link_enc))
+		return false;
+
+	/* Check for which front end is used by this encoder.
+	 * Note the inst is 1 indexed, where 0 is undefined.
+	 * Note that DIG_FE can source from different OTG but our
+	 * current implementation always map 1-to-1, so this code makes
+	 * the same assumption and doesn't check OTG source.
+	 */
+	inst = link->link_enc->funcs->get_dig_frontend(link->link_enc) - 1;
+
+	/* Instance should be within the range of the pool */
+	if (inst >= dc->res_pool->pipe_count)
+		return false;
+
+	tg = dc->res_pool->timing_generators[inst];
+
+	if (!tg->funcs->is_matching_timing)
+		return false;
+
+	if (!tg->funcs->is_matching_timing(tg, crtc_timing))
+		return false;
+
+	if (dc_is_dp_signal(link->connector_signal)) {
+		unsigned int pix_clk_100hz;
+
+		dc->res_pool->dp_clock_source->funcs->get_pixel_clk_frequency_100hz(
+			dc->res_pool->dp_clock_source,
+			inst, &pix_clk_100hz);
+
+		if (crtc_timing->pix_clk_100hz != pix_clk_100hz)
+			return false;
+	}
+
+	return true;
+}
+
 bool dc_enable_stereo(
 	struct dc *dc,
 	struct dc_state *context,

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

@@ -594,6 +594,10 @@ struct dc_validation_set {
 	uint8_t plane_count;
 };
 
+bool dc_validate_seamless_boot_timing(struct dc *dc,
+				const struct dc_sink *sink,
+				struct dc_crtc_timing *crtc_timing);
+
 enum dc_status dc_validate_plane(struct dc *dc, const struct dc_plane_state *plane_state);
 
 void get_clock_requirements_for_state(struct dc_state *state, struct AsicStateEx *info);

drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c

@@ -977,6 +977,28 @@ static bool dce110_clock_source_power_down(
 	return bp_result == BP_RESULT_OK;
 }
 
+static bool get_pixel_clk_frequency_100hz(
+		struct clock_source *clock_source,
+		unsigned int inst,
+		unsigned int *pixel_clk_khz)
+{
+	struct dce110_clk_src *clk_src = TO_DCE110_CLK_SRC(clock_source);
+	unsigned int clock_hz = 0;
+
+	if (clock_source->id == CLOCK_SOURCE_ID_DP_DTO) {
+		clock_hz = REG_READ(PHASE[inst]);
+
+		/* NOTE: There is agreement with VBIOS here that MODULO is
+		 * programmed equal to DPREFCLK, in which case PHASE will be
+		 * equivalent to pixel clock.
+		 */
+		*pixel_clk_khz = clock_hz / 100;
+		return true;
+	}
+
+	return false;
+}
+
 /*****************************************/
 /* Constructor                           */
 /*****************************************/
@@ -984,12 +1006,14 @@ static bool dce110_clock_source_power_down(
 static const struct clock_source_funcs dce112_clk_src_funcs = {
 	.cs_power_down = dce110_clock_source_power_down,
 	.program_pix_clk = dce112_program_pix_clk,
-	.get_pix_clk_dividers = dce112_get_pix_clk_dividers
+	.get_pix_clk_dividers = dce112_get_pix_clk_dividers,
+	.get_pixel_clk_frequency_100hz = get_pixel_clk_frequency_100hz
 };
 static const struct clock_source_funcs dce110_clk_src_funcs = {
 	.cs_power_down = dce110_clock_source_power_down,
 	.program_pix_clk = dce110_program_pix_clk,
-	.get_pix_clk_dividers = dce110_get_pix_clk_dividers
+	.get_pix_clk_dividers = dce110_get_pix_clk_dividers,
+	.get_pixel_clk_frequency_100hz = get_pixel_clk_frequency_100hz
 };
 
 

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_link_encoder.c

@@ -85,6 +85,7 @@ static const struct link_encoder_funcs dcn10_lnk_enc_funcs = {
 	.enable_hpd = dcn10_link_encoder_enable_hpd,
 	.disable_hpd = dcn10_link_encoder_disable_hpd,
 	.is_dig_enabled = dcn10_is_dig_enabled,
+	.get_dig_frontend = dcn10_get_dig_frontend,
 	.destroy = dcn10_link_encoder_destroy
 };
 
@@ -495,6 +496,15 @@ bool dcn10_is_dig_enabled(struct link_encoder *enc)
 	return value;
 }
 
+unsigned int dcn10_get_dig_frontend(struct link_encoder *enc)
+{
+	struct dcn10_link_encoder *enc10 = TO_DCN10_LINK_ENC(enc);
+	uint32_t value;
+
+	REG_GET(DIG_BE_CNTL, DIG_FE_SOURCE_SELECT, &value);
+	return value;
+}
+
 static void link_encoder_disable(struct dcn10_link_encoder *enc10)
 {
 	/* reset training pattern */

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_link_encoder.h

@@ -336,6 +336,8 @@ void dcn10_psr_program_secondary_packet(struct link_encoder *enc,
 
 bool dcn10_is_dig_enabled(struct link_encoder *enc);
 
+unsigned int dcn10_get_dig_frontend(struct link_encoder *enc);
+
 void dcn10_aux_initialize(struct dcn10_link_encoder *enc10);
 
 #endif /* __DC_LINK_ENCODER__DCN10_H__ */

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c

@@ -1208,6 +1208,64 @@ bool optc1_is_stereo_left_eye(struct timing_generator *optc)
 	return ret;
 }
 
+bool optc1_is_matching_timing(struct timing_generator *tg,
+		const struct dc_crtc_timing *otg_timing)
+{
+	struct dc_crtc_timing hw_crtc_timing = {0};
+	struct dcn_otg_state s = {0};
+
+	if (tg == NULL || otg_timing == NULL)
+		return false;
+
+	optc1_read_otg_state(DCN10TG_FROM_TG(tg), &s);
+
+	hw_crtc_timing.h_total = s.h_total + 1;
+	hw_crtc_timing.h_addressable = s.h_total - ((s.h_total - s.h_blank_start) + s.h_blank_end);
+	hw_crtc_timing.h_front_porch = s.h_total + 1 - s.h_blank_start;
+	hw_crtc_timing.h_sync_width = s.h_sync_a_end - s.h_sync_a_start;
+
+	hw_crtc_timing.v_total = s.v_total + 1;
+	hw_crtc_timing.v_addressable = s.v_total - ((s.v_total - s.v_blank_start) + s.v_blank_end);
+	hw_crtc_timing.v_front_porch = s.v_total + 1 - s.v_blank_start;
+	hw_crtc_timing.v_sync_width = s.v_sync_a_end - s.v_sync_a_start;
+
+	if (otg_timing->h_total != hw_crtc_timing.h_total)
+		return false;
+
+	if (otg_timing->h_border_left != hw_crtc_timing.h_border_left)
+		return false;
+
+	if (otg_timing->h_addressable != hw_crtc_timing.h_addressable)
+		return false;
+
+	if (otg_timing->h_border_right != hw_crtc_timing.h_border_right)
+		return false;
+
+	if (otg_timing->h_front_porch != hw_crtc_timing.h_front_porch)
+		return false;
+
+	if (otg_timing->h_sync_width != hw_crtc_timing.h_sync_width)
+		return false;
+
+	if (otg_timing->v_total != hw_crtc_timing.v_total)
+		return false;
+
+	if (otg_timing->v_border_top != hw_crtc_timing.v_border_top)
+		return false;
+
+	if (otg_timing->v_addressable != hw_crtc_timing.v_addressable)
+		return false;
+
+	if (otg_timing->v_border_bottom != hw_crtc_timing.v_border_bottom)
+		return false;
+
+	if (otg_timing->v_sync_width != hw_crtc_timing.v_sync_width)
+		return false;
+
+	return true;
+}
+
+
 void optc1_read_otg_state(struct optc *optc1,
 		struct dcn_otg_state *s)
 {
@@ -1404,6 +1462,7 @@ static const struct timing_generator_funcs dcn10_tg_funcs = {
 		.get_frame_count = optc1_get_vblank_counter,
 		.get_scanoutpos = optc1_get_crtc_scanoutpos,
 		.get_otg_active_size = optc1_get_otg_active_size,
+		.is_matching_timing = optc1_is_matching_timing,
 		.set_early_control = optc1_set_early_control,
 		/* used by enable_timing_synchronization. Not need for FPGA */
 		.wait_for_state = optc1_wait_for_state,

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

@@ -166,6 +166,10 @@ struct clock_source_funcs {
 			struct clock_source *,
 			struct pixel_clk_params *,
 			struct pll_settings *);
+	bool (*get_pixel_clk_frequency_100hz)(
+			struct clock_source *clock_source,
+			unsigned int inst,
+			unsigned int *pixel_clk_khz);
 };
 
 struct clock_source {

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

@@ -153,6 +153,7 @@ struct link_encoder_funcs {
 	void (*enable_hpd)(struct link_encoder *enc);
 	void (*disable_hpd)(struct link_encoder *enc);
 	bool (*is_dig_enabled)(struct link_encoder *enc);
+	unsigned int (*get_dig_frontend)(struct link_encoder *enc);
 	void (*destroy)(struct link_encoder **enc);
 };
 

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

@@ -170,6 +170,8 @@ struct timing_generator_funcs {
 	bool (*get_otg_active_size)(struct timing_generator *optc,
 			uint32_t *otg_active_width,
 			uint32_t *otg_active_height);
+	bool (*is_matching_timing)(struct timing_generator *tg,
+			const struct dc_crtc_timing *otg_timing);
 	void (*set_early_control)(struct timing_generator *tg,
 							   uint32_t early_cntl);
 	void (*wait_for_state)(struct timing_generator *tg,