[PATCH 03/14] drm/amd/display: Skip override for preferred link settings during link training

Solomon Chiu solomon.chiu at amd.com
Fri Oct 1 14:36:09 UTC 2021


From: George Shen <george.shen at amd.com>

[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 at amd.com>
Acked-by: Solomon Chiu <solomon.chiu at amd.com>
Signed-off-by: George Shen <george.shen at amd.com>
---
 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 029cc78bc9e9..649a9da338a7 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
@@ -1645,12 +1645,6 @@ 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 ?
-- 
2.25.1



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