Commit eb280189 authored by Zhongwei's avatar Zhongwei Committed by Alex Deucher
Browse files

drm/amd/display: force toggle rate wa for first link training for a retimer 



[WHY]
Handover from DMUB to driver does not perform link rate toggle.
It might cause link training failure for boot up.

[HOW]
Force toggle rate wa for first link train.
link->vendor_specific_lttpr_link_rate_wa should be zero then.

Cc: stable@vger.kernel.org # 6.1+
Reviewed-by: default avatarMichael Strauss <michael.strauss@amd.com>
Acked-by: default avatarHamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: default avatarZhongwei <zhongwei.zhang@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent c6df7f31

drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c

+3 −3
Original line number Diff line number Diff line
@@ -115,7 +115,7 @@ static enum link_training_result perform_fixed_vs_pe_nontransparent_training_seq 
		lt_settings->cr_pattern_time = 16000;



	/* Fixed VS/PE specific: Toggle link rate */

	apply_toggle_rate_wa = (link->vendor_specific_lttpr_link_rate_wa == target_rate);

	apply_toggle_rate_wa = ((link->vendor_specific_lttpr_link_rate_wa == target_rate) || (link->vendor_specific_lttpr_link_rate_wa == 0));

	target_rate = get_dpcd_link_rate(&lt_settings->link_settings);

	toggle_rate = (target_rate == 0x6) ? 0xA : 0x6;
@@ -271,7 +271,7 @@ enum link_training_result dp_perform_fixed_vs_pe_training_sequence_legacy( 
	/* Vendor specific: Toggle link rate */

	toggle_rate = (rate == 0x6) ? 0xA : 0x6;



	if (link->vendor_specific_lttpr_link_rate_wa == rate) {

	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,
@@ -617,7 +617,7 @@ enum link_training_result dp_perform_fixed_vs_pe_training_sequence( 
	/* Vendor specific: Toggle link rate */

	toggle_rate = (rate == 0x6) ? 0xA : 0x6;



	if (link->vendor_specific_lttpr_link_rate_wa == rate) {

	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,