drm/amd/display: Remove Legacy FIXED_VS Transparent LT Sequence

The New sequence has been in use in DCN314 with no regressions
introduced. Therefore, it is safe to enable this sequence for all
devices using FIXED_VS retimers. So, remove the legacy codepath and its
associated config flag.

Reviewed-by: Ovidiu Bunea <ovidiu.bunea@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

5 files changed, 1 insertions, 362 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/dc.h b/drivers/gpu/drm/amd/display/dc/dc.h
index 5d95b1e9dafb..74c871917eaf 100644
--- a/drivers/gpu/drm/amd/display/dc/dc.h
+++ b/drivers/gpu/drm/amd/display/dc/dc.h
@@ -429,7 +429,6 @@ struct dc_config {
 	bool force_bios_enable_lttpr;
 	uint8_t force_bios_fixed_vs;
 	int sdpif_request_limit_words_per_umc;
-	bool use_old_fixed_vs_sequence;
 	bool dc_mode_clk_limit_support;
 	bool EnableMinDispClkODM;
 	bool enable_auto_dpm_test_logs;
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training.c
index 5a0b04518956..e06d3c2d8910 100644
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training.c
+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training.c
@@ -1505,10 +1505,7 @@ enum link_training_result dp_perform_link_training(
 	 * Non-LT AUX transactions inside training mode.
 	 */
 	if ((link->chip_caps & EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN) && encoding == DP_8b_10b_ENCODING)
-		if (link->dc->config.use_old_fixed_vs_sequence)
-			status = dp_perform_fixed_vs_pe_training_sequence_legacy(link, link_res, &lt_settings);
-		else
-			status = dp_perform_fixed_vs_pe_training_sequence(link, link_res, &lt_settings);
+		status = dp_perform_fixed_vs_pe_training_sequence(link, link_res, &lt_settings);
 	else if (encoding == DP_8b_10b_ENCODING)
 		status = dp_perform_8b_10b_link_training(link, link_res, &lt_settings);
 	else if (encoding == DP_128b_132b_ENCODING)
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c
index 7087cdc9e977..c36e0e5df447 100644
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c
+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c
@@ -186,356 +186,6 @@ static enum link_training_result perform_fixed_vs_pe_nontransparent_training_seq
 	return status;
 }
 
-
-enum link_training_result dp_perform_fixed_vs_pe_training_sequence_legacy(
-	struct dc_link *link,
-	const struct link_resource *link_res,
-	struct link_training_settings *lt_settings)
-{
-	const uint8_t vendor_lttpr_write_data_reset[4] = {0x1, 0x50, 0x63, 0xFF};
-	const uint8_t offset = dp_parse_lttpr_repeater_count(
-			link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
-	const uint8_t vendor_lttpr_write_data_intercept_en[4] = {0x1, 0x55, 0x63, 0x0};
-	const uint8_t vendor_lttpr_write_data_intercept_dis[4] = {0x1, 0x55, 0x63, 0x68};
-	uint32_t pre_disable_intercept_delay_ms = 0;
-	uint8_t vendor_lttpr_write_data_vs[4] = {0x1, 0x51, 0x63, 0x0};
-	uint8_t vendor_lttpr_write_data_pe[4] = {0x1, 0x52, 0x63, 0x0};
-	const uint8_t vendor_lttpr_write_data_4lane_1[4] = {0x1, 0x6E, 0xF2, 0x19};
-	const uint8_t vendor_lttpr_write_data_4lane_2[4] = {0x1, 0x6B, 0xF2, 0x01};
-	const uint8_t vendor_lttpr_write_data_4lane_3[4] = {0x1, 0x6D, 0xF2, 0x18};
-	const uint8_t vendor_lttpr_write_data_4lane_4[4] = {0x1, 0x6C, 0xF2, 0x03};
-	const uint8_t vendor_lttpr_write_data_4lane_5[4] = {0x1, 0x03, 0xF3, 0x06};
-	const uint8_t vendor_lttpr_write_data_dpmf[4] = {0x1, 0x6, 0x70, 0x87};
-	enum link_training_result status = LINK_TRAINING_SUCCESS;
-	uint8_t lane = 0;
-	union down_spread_ctrl downspread = {0};
-	union lane_count_set lane_count_set = {0};
-	uint8_t toggle_rate;
-	uint8_t rate;
-
-	/* Only 8b/10b is supported */
-	ASSERT(link_dp_get_encoding_format(&lt_settings->link_settings) ==
-			DP_8b_10b_ENCODING);
-
-	if (lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) {
-		status = perform_fixed_vs_pe_nontransparent_training_sequence(link, link_res, lt_settings);
-		return status;
-	}
-
-	if (offset != 0xFF) {
-		if (offset == 2) {
-			pre_disable_intercept_delay_ms = link->dc->debug.fixed_vs_aux_delay_config_wa;
-
-		/* Certain display and cable configuration require extra delay */
-		} else if (offset > 2) {
-			pre_disable_intercept_delay_ms = link->dc->debug.fixed_vs_aux_delay_config_wa * 2;
-		}
-	}
-
-	/* Vendor specific: Reset lane settings */
-	link_configure_fixed_vs_pe_retimer(link->ddc,
-			&vendor_lttpr_write_data_reset[0], sizeof(vendor_lttpr_write_data_reset));
-	link_configure_fixed_vs_pe_retimer(link->ddc,
-			&vendor_lttpr_write_data_vs[0], sizeof(vendor_lttpr_write_data_vs));
-	link_configure_fixed_vs_pe_retimer(link->ddc,
-			&vendor_lttpr_write_data_pe[0], sizeof(vendor_lttpr_write_data_pe));
-
-	/* Vendor specific: Enable intercept */
-	link_configure_fixed_vs_pe_retimer(link->ddc,
-			&vendor_lttpr_write_data_intercept_en[0], sizeof(vendor_lttpr_write_data_intercept_en));
-
-
-	/* 1. set link rate, lane count and spread. */
-
-	downspread.raw = (uint8_t)(lt_settings->link_settings.link_spread);
-
-	lane_count_set.bits.LANE_COUNT_SET =
-	lt_settings->link_settings.lane_count;
-
-	lane_count_set.bits.ENHANCED_FRAMING = lt_settings->enhanced_framing;
-	lane_count_set.bits.POST_LT_ADJ_REQ_GRANTED = 0;
-
-
-	if (lt_settings->pattern_for_eq < DP_TRAINING_PATTERN_SEQUENCE_4) {
-		lane_count_set.bits.POST_LT_ADJ_REQ_GRANTED =
-				link->dpcd_caps.max_ln_count.bits.POST_LT_ADJ_REQ_SUPPORTED;
-	}
-
-	core_link_write_dpcd(link, DP_DOWNSPREAD_CTRL,
-		&downspread.raw, sizeof(downspread));
-
-	core_link_write_dpcd(link, DP_LANE_COUNT_SET,
-		&lane_count_set.raw, 1);
-
-	rate = get_dpcd_link_rate(&lt_settings->link_settings);
-
-	/* Vendor specific: Toggle link rate */
-	toggle_rate = (rate == 0x6) ? 0xA : 0x6;
-
-	if (link->vendor_specific_lttpr_link_rate_wa == rate || link->vendor_specific_lttpr_link_rate_wa == 0) {
-		core_link_write_dpcd(
-				link,
-				DP_LINK_BW_SET,
-				&toggle_rate,
-				1);
-	}
-
-	link->vendor_specific_lttpr_link_rate_wa = rate;
-
-	core_link_write_dpcd(link, DP_LINK_BW_SET, &rate, 1);
-
-	DC_LOG_HW_LINK_TRAINING("%s\n %x rate = %x\n %x lane = %x framing = %x\n %x spread = %x\n",
-		__func__,
-		DP_LINK_BW_SET,
-		lt_settings->link_settings.link_rate,
-		DP_LANE_COUNT_SET,
-		lt_settings->link_settings.lane_count,
-		lt_settings->enhanced_framing,
-		DP_DOWNSPREAD_CTRL,
-		lt_settings->link_settings.link_spread);
-
-	link_configure_fixed_vs_pe_retimer(link->ddc,
-			&vendor_lttpr_write_data_dpmf[0],
-			sizeof(vendor_lttpr_write_data_dpmf));
-
-	if (lt_settings->link_settings.lane_count == LANE_COUNT_FOUR) {
-		link_configure_fixed_vs_pe_retimer(link->ddc,
-				&vendor_lttpr_write_data_4lane_1[0], sizeof(vendor_lttpr_write_data_4lane_1));
-		link_configure_fixed_vs_pe_retimer(link->ddc,
-				&vendor_lttpr_write_data_4lane_2[0], sizeof(vendor_lttpr_write_data_4lane_2));
-		link_configure_fixed_vs_pe_retimer(link->ddc,
-				&vendor_lttpr_write_data_4lane_3[0], sizeof(vendor_lttpr_write_data_4lane_3));
-		link_configure_fixed_vs_pe_retimer(link->ddc,
-				&vendor_lttpr_write_data_4lane_4[0], sizeof(vendor_lttpr_write_data_4lane_4));
-		link_configure_fixed_vs_pe_retimer(link->ddc,
-				&vendor_lttpr_write_data_4lane_5[0], sizeof(vendor_lttpr_write_data_4lane_5));
-	}
-
-	/* 2. Perform link training */
-
-	/* Perform Clock Recovery Sequence */
-	if (status == LINK_TRAINING_SUCCESS) {
-		const uint8_t max_vendor_dpcd_retries = 10;
-		uint32_t retries_cr;
-		uint32_t retry_count;
-		uint32_t wait_time_microsec;
-		enum dc_lane_count lane_count = lt_settings->link_settings.lane_count;
-		union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX];
-		union lane_align_status_updated dpcd_lane_status_updated;
-		union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0};
-		uint8_t i = 0;
-
-		retries_cr = 0;
-		retry_count = 0;
-
-		memset(&dpcd_lane_status, '\0', sizeof(dpcd_lane_status));
-		memset(&dpcd_lane_status_updated, '\0',
-		sizeof(dpcd_lane_status_updated));
-
-		while ((retries_cr < LINK_TRAINING_MAX_RETRY_COUNT) &&
-			(retry_count < LINK_TRAINING_MAX_CR_RETRY)) {
-
-
-			/* 1. call HWSS to set lane settings */
-			dp_set_hw_lane_settings(
-					link,
-					link_res,
-					lt_settings,
-					0);
-
-			/* 2. update DPCD of the receiver */
-			if (!retry_count) {
-				/* EPR #361076 - write as a 5-byte burst,
-				 * but only for the 1-st iteration.
-				 */
-				dpcd_set_lt_pattern_and_lane_settings(
-						link,
-						lt_settings,
-						lt_settings->pattern_for_cr,
-						0);
-				/* Vendor specific: Disable intercept */
-				for (i = 0; i < max_vendor_dpcd_retries; i++) {
-					if (pre_disable_intercept_delay_ms != 0)
-						msleep(pre_disable_intercept_delay_ms);
-					if (link_configure_fixed_vs_pe_retimer(link->ddc,
-							&vendor_lttpr_write_data_intercept_dis[0],
-							sizeof(vendor_lttpr_write_data_intercept_dis)))
-						break;
-
-					link_configure_fixed_vs_pe_retimer(link->ddc,
-							&vendor_lttpr_write_data_intercept_en[0],
-							sizeof(vendor_lttpr_write_data_intercept_en));
-				}
-			} else {
-				vendor_lttpr_write_data_vs[3] = 0;
-				vendor_lttpr_write_data_pe[3] = 0;
-
-				for (lane = 0; lane < lane_count; lane++) {
-					vendor_lttpr_write_data_vs[3] |=
-							lt_settings->dpcd_lane_settings[lane].bits.VOLTAGE_SWING_SET << (2 * lane);
-					vendor_lttpr_write_data_pe[3] |=
-							lt_settings->dpcd_lane_settings[lane].bits.PRE_EMPHASIS_SET << (2 * lane);
-				}
-
-				/* Vendor specific: Update VS and PE to DPRX requested value */
-				link_configure_fixed_vs_pe_retimer(link->ddc,
-						&vendor_lttpr_write_data_vs[0], sizeof(vendor_lttpr_write_data_vs));
-				link_configure_fixed_vs_pe_retimer(link->ddc,
-						&vendor_lttpr_write_data_pe[0], sizeof(vendor_lttpr_write_data_pe));
-
-				dpcd_set_lane_settings(
-						link,
-						lt_settings,
-						0);
-			}
-
-			/* 3. wait receiver to lock-on*/
-			wait_time_microsec = lt_settings->cr_pattern_time;
-
-			dp_wait_for_training_aux_rd_interval(
-					link,
-					wait_time_microsec);
-
-			/* 4. Read lane status and requested drive
-			 * settings as set by the sink
-			 */
-			dp_get_lane_status_and_lane_adjust(
-					link,
-					lt_settings,
-					dpcd_lane_status,
-					&dpcd_lane_status_updated,
-					dpcd_lane_adjust,
-					0);
-
-			/* 5. check CR done*/
-			if (dp_is_cr_done(lane_count, dpcd_lane_status)) {
-				status = LINK_TRAINING_SUCCESS;
-				break;
-			}
-
-			/* 6. max VS reached*/
-			if (dp_is_max_vs_reached(lt_settings))
-				break;
-
-			/* 7. same lane settings */
-			/* Note: settings are the same for all lanes,
-			 * so comparing first lane is sufficient
-			 */
-			if (lt_settings->dpcd_lane_settings[0].bits.VOLTAGE_SWING_SET ==
-					dpcd_lane_adjust[0].bits.VOLTAGE_SWING_LANE)
-				retries_cr++;
-			else
-				retries_cr = 0;
-
-			/* 8. update VS/PE/PC2 in lt_settings*/
-			dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
-					lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
-			retry_count++;
-		}
-
-		if (retry_count >= LINK_TRAINING_MAX_CR_RETRY) {
-			ASSERT(0);
-			DC_LOG_ERROR("%s: Link Training Error, could not get CR after %d tries. Possibly voltage swing issue",
-				__func__,
-				LINK_TRAINING_MAX_CR_RETRY);
-
-		}
-
-		status = dp_get_cr_failure(lane_count, dpcd_lane_status);
-	}
-
-	/* Perform Channel EQ Sequence */
-	if (status == LINK_TRAINING_SUCCESS) {
-		enum dc_dp_training_pattern tr_pattern;
-		uint32_t retries_ch_eq;
-		uint32_t wait_time_microsec;
-		enum dc_lane_count lane_count = lt_settings->link_settings.lane_count;
-		union lane_align_status_updated dpcd_lane_status_updated = {0};
-		union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX] = {0};
-		union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0};
-
-		/* Note: also check that TPS4 is a supported feature*/
-		tr_pattern = lt_settings->pattern_for_eq;
-
-		dp_set_hw_training_pattern(link, link_res, tr_pattern, 0);
-
-		status = LINK_TRAINING_EQ_FAIL_EQ;
-
-		for (retries_ch_eq = 0; retries_ch_eq <= LINK_TRAINING_MAX_RETRY_COUNT;
-			retries_ch_eq++) {
-
-			dp_set_hw_lane_settings(link, link_res, lt_settings, 0);
-
-			vendor_lttpr_write_data_vs[3] = 0;
-			vendor_lttpr_write_data_pe[3] = 0;
-
-			for (lane = 0; lane < lane_count; lane++) {
-				vendor_lttpr_write_data_vs[3] |=
-						lt_settings->dpcd_lane_settings[lane].bits.VOLTAGE_SWING_SET << (2 * lane);
-				vendor_lttpr_write_data_pe[3] |=
-						lt_settings->dpcd_lane_settings[lane].bits.PRE_EMPHASIS_SET << (2 * lane);
-			}
-
-			/* Vendor specific: Update VS and PE to DPRX requested value */
-			link_configure_fixed_vs_pe_retimer(link->ddc,
-					&vendor_lttpr_write_data_vs[0], sizeof(vendor_lttpr_write_data_vs));
-			link_configure_fixed_vs_pe_retimer(link->ddc,
-					&vendor_lttpr_write_data_pe[0], sizeof(vendor_lttpr_write_data_pe));
-
-			/* 2. update DPCD*/
-			if (!retries_ch_eq)
-				/* EPR #361076 - write as a 5-byte burst,
-				 * but only for the 1-st iteration
-				 */
-
-				dpcd_set_lt_pattern_and_lane_settings(
-					link,
-					lt_settings,
-					tr_pattern, 0);
-			else
-				dpcd_set_lane_settings(link, lt_settings, 0);
-
-			/* 3. wait for receiver to lock-on*/
-			wait_time_microsec = lt_settings->eq_pattern_time;
-
-			dp_wait_for_training_aux_rd_interval(
-					link,
-					wait_time_microsec);
-
-			/* 4. Read lane status and requested
-			 * drive settings as set by the sink
-			 */
-			dp_get_lane_status_and_lane_adjust(
-				link,
-				lt_settings,
-				dpcd_lane_status,
-				&dpcd_lane_status_updated,
-				dpcd_lane_adjust,
-				0);
-
-			/* 5. check CR done*/
-			if (!dp_is_cr_done(lane_count, dpcd_lane_status)) {
-				status = LINK_TRAINING_EQ_FAIL_CR;
-				break;
-			}
-
-			/* 6. check CHEQ done*/
-			if (dp_is_ch_eq_done(lane_count, dpcd_lane_status) &&
-					dp_is_symbol_locked(lane_count, dpcd_lane_status) &&
-					dp_is_interlane_aligned(dpcd_lane_status_updated)) {
-				status = LINK_TRAINING_SUCCESS;
-				break;
-			}
-
-			/* 7. update VS/PE/PC2 in lt_settings*/
-			dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
-					lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
-		}
-	}
-
-	return status;
-}
-
 enum link_training_result dp_perform_fixed_vs_pe_training_sequence(
 	struct dc_link *link,
 	const struct link_resource *link_res,
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.h b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.h
index c0d6ea329504..e61970e27661 100644
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.h
+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.h
@@ -28,11 +28,6 @@
 #define __DC_LINK_DP_FIXED_VS_PE_RETIMER_H__
 #include "link_dp_training.h"
 
-enum link_training_result dp_perform_fixed_vs_pe_training_sequence_legacy(
-	struct dc_link *link,
-	const struct link_resource *link_res,
-	struct link_training_settings *lt_settings);
-
 enum link_training_result dp_perform_fixed_vs_pe_training_sequence(
 	struct dc_link *link,
 	const struct link_resource *link_res,
diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn31/dcn31_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn31/dcn31_resource.c
index 31035fc3d868..04d142f97474 100644
--- a/drivers/gpu/drm/amd/display/dc/resource/dcn31/dcn31_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dcn31/dcn31_resource.c
@@ -1941,8 +1941,6 @@ static bool dcn31_resource_construct(
 	dc->caps.color.mpc.ogam_rom_caps.hlg = 0;
 	dc->caps.color.mpc.ocsc = 1;
 
-	dc->config.use_old_fixed_vs_sequence = true;
-
 	/* Use pipe context based otg sync logic */
 	dc->config.use_pipe_ctx_sync_logic = true;