Commit 31cf79f0 authored by Jimmy Kizito's avatar Jimmy Kizito Committed by Alex Deucher
Browse files

drm/amd/display: Skip DPCD read for DPTX-to-DPIA hop 



[why & how]
Driver does not need to train the first hop.

Reviewed-by: default avatarJun Lei <Jun.Lei@amd.com>
Acked-by: default avatarWayne Lin <Wayne.Lin@amd.com>
Acked-by: default avatarNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Acked-by: default avatarHarry Wentland <harry.wentland@amd.com>
Signed-off-by: default avatarJimmy Kizito <Jimmy.Kizito@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 99447622

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

+7 −0
Original line number Diff line number Diff line
@@ -1775,6 +1775,13 @@ static enum dc_status configure_lttpr_mode_non_transparent( 


		if (encoding == DP_8b_10b_ENCODING) {

			repeater_cnt = dp_convert_to_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt);



			/* Driver does not need to train the first hop. Skip DPCD read and clear

			 * AUX_RD_INTERVAL for DPTX-to-DPIA hop.

			 */

			if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA)

				link->dpcd_caps.lttpr_caps.aux_rd_interval[--repeater_cnt] = 0;



			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));