drm/amd/display: consider channel coding in configure lttpr mode

[why]
Some lttpr configuration steps are exclusive to 8b/10b channel
coding mode. We need to take channel conding into account.
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Reviewed-by: George Shen <George.Shen@amd.com>
Acked-by: Stylon Wang <stylon.wang@amd.com>
Acked-by: Wesley Chalmers <Wesley.Chalmers@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_link_dp.c

@@ -1275,6 +1275,8 @@ static inline void decide_8b_10b_training_settings(
 	else
 		lt_settings->link_settings.link_spread = LINK_SPREAD_05_DOWNSPREAD_30KHZ;
 
+	lt_settings->lttpr_mode = link->lttpr_mode;
+
 	/* Initialize lane settings overrides */
 	if (overrides->voltage_swing != NULL)
 		lt_settings->voltage_swing = overrides->voltage_swing;
@@ -1367,13 +1369,16 @@ static void configure_lttpr_mode_transparent(struct dc_link *link)
 {
 	uint8_t repeater_mode = DP_PHY_REPEATER_MODE_TRANSPARENT;
 
+	DC_LOG_HW_LINK_TRAINING("%s\n Set LTTPR to Transparent Mode\n", __func__);
 	core_link_write_dpcd(link,
 			DP_PHY_REPEATER_MODE,
 			(uint8_t *)&repeater_mode,
 			sizeof(repeater_mode));
 }
 
-static void configure_lttpr_mode_non_transparent(struct dc_link *link)
+static void configure_lttpr_mode_non_transparent(
+		struct dc_link *link,
+		const struct link_training_settings *lt_settings)
 {
 	/* aux timeout is already set to extended */
 	/* RESET/SET lttpr mode to enable non transparent mode */
@@ -1383,11 +1388,16 @@ static void configure_lttpr_mode_non_transparent(struct dc_link *link)
 	enum dc_status result = DC_ERROR_UNEXPECTED;
 	uint8_t repeater_mode = DP_PHY_REPEATER_MODE_TRANSPARENT;
 
-	DC_LOG_HW_LINK_TRAINING("%s\n Set LTTPR to Transparent Mode\n", __func__);
-	result = core_link_write_dpcd(link,
-			DP_PHY_REPEATER_MODE,
-			(uint8_t *)&repeater_mode,
-			sizeof(repeater_mode));
+	enum dp_link_encoding encoding = dp_get_link_encoding_format(&lt_settings->link_settings);
+
+	if (encoding == DP_8b_10b_ENCODING) {
+		DC_LOG_HW_LINK_TRAINING("%s\n Set LTTPR to Transparent Mode\n", __func__);
+		result = core_link_write_dpcd(link,
+				DP_PHY_REPEATER_MODE,
+				(uint8_t *)&repeater_mode,
+				sizeof(repeater_mode));
+
+	}
 
 	if (result == DC_OK) {
 		link->dpcd_caps.lttpr_caps.mode = repeater_mode;
@@ -1407,17 +1417,18 @@ static void configure_lttpr_mode_non_transparent(struct dc_link *link)
 			link->dpcd_caps.lttpr_caps.mode = repeater_mode;
 		}
 
-		repeater_cnt = dp_convert_to_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
-
-		for (repeater_id = repeater_cnt; repeater_id > 0; repeater_id--) {
-			aux_interval_address = DP_TRAINING_AUX_RD_INTERVAL_PHY_REPEATER1 +
-						((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (repeater_id - 1));
-			core_link_read_dpcd(
-				link,
-				aux_interval_address,
-				(uint8_t *)&link->dpcd_caps.lttpr_caps.aux_rd_interval[repeater_id - 1],
-				sizeof(link->dpcd_caps.lttpr_caps.aux_rd_interval[repeater_id - 1]));
-			link->dpcd_caps.lttpr_caps.aux_rd_interval[repeater_id - 1] &= 0x7F;
+		if (encoding == DP_8b_10b_ENCODING) {
+			repeater_cnt = dp_convert_to_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
+			for (repeater_id = repeater_cnt; repeater_id > 0; repeater_id--) {
+				aux_interval_address = DP_TRAINING_AUX_RD_INTERVAL_PHY_REPEATER1 +
+							((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (repeater_id - 1));
+				core_link_read_dpcd(
+					link,
+					aux_interval_address,
+					(uint8_t *)&link->dpcd_caps.lttpr_caps.aux_rd_interval[repeater_id - 1],
+					sizeof(link->dpcd_caps.lttpr_caps.aux_rd_interval[repeater_id - 1]));
+				link->dpcd_caps.lttpr_caps.aux_rd_interval[repeater_id - 1] &= 0x7F;
+			}
 		}
 	}
 }
@@ -1611,7 +1622,7 @@ enum link_training_result dc_link_dp_perform_link_training(
 
 	/* Configure lttpr mode */
 	if (link->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT)
-		configure_lttpr_mode_non_transparent(link);
+		configure_lttpr_mode_non_transparent(link, &lt_settings);
 	else if (link->lttpr_mode == LTTPR_MODE_TRANSPARENT)
 		configure_lttpr_mode_transparent(link);
 

drivers/gpu/drm/amd/display/include/link_service_types.h

@@ -93,6 +93,7 @@ struct link_training_settings {
 
 	bool enhanced_framing;
 	bool allow_invalid_msa_timing_param;
+	enum lttpr_mode lttpr_mode;
 };
 
 /*TODO: Move this enum test harness*/