From c991b22d66eb69562425566e30746e779af7e761 Mon Sep 17 00:00:00 2001
From: George Shen <george.shen@amd.com>
Date: Fri, 1 Oct 2021 22:36:09 +0800
Subject: drm/amd/display: Skip override for preferred link settings during
link training
Git-commit: 2387033ac0db3235f3fa9d9976aeeeb50349550e
Patch-mainline: v5.15-rc5
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
[Why]
Overriding link setting inside override_training_settings
result in fallback link settings being ignored. This can
potentially cause link training to always fail and consequently
result in an infinite loop of link training to occur in
dp_verify_link_cap during detection.
[How]
Since preferred link settings are already considered inside
decide_link_settings, skip the check in override_training_settings
to avoid infinite link training loops.
Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Acked-by: Solomon Chiu <solomon.chiu@amd.com>
Signed-off-by: George Shen <george.shen@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 6 ------
1 file changed, 6 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
index 05eaec03d9f7..6d655e158267 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
@@ -1306,12 +1306,6 @@ static void override_training_settings(
{
uint32_t lane;
- /* Override link settings */
- if (link->preferred_link_setting.link_rate != LINK_RATE_UNKNOWN)
- lt_settings->link_settings.link_rate = link->preferred_link_setting.link_rate;
- if (link->preferred_link_setting.lane_count != LANE_COUNT_UNKNOWN)
- lt_settings->link_settings.lane_count = link->preferred_link_setting.lane_count;
-
/* Override link spread */
if (!link->dp_ss_off && overrides->downspread != NULL)
lt_settings->link_settings.link_spread = *overrides->downspread ?
--
2.38.1