From 211f07f3a410f0a20c1c7901a7e62eec2d816ff7 Mon Sep 17 00:00:00 2001
From: George Shen <George.Shen@amd.com>
Date: Thu, 2 Dec 2021 23:07:35 -0500
Subject: drm/amd/display: Limit max link cap with LTTPR caps
Git-commit: fddb024537f121995957d816fcf8e2e230451db2
Patch-mainline: v5.17-rc1
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]
Max link rate should be limited to the maximum link rate support by any
LTTPR that are connected, including when operating in transparent mode.
[How]
Include transparent mode when factoring in LTTPR max supported link
rate.
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Wesley Chalmers <wesley.chalmers@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@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 | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
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 8a35370da867..6f552f7ee1db 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
@@ -2873,7 +2873,7 @@ static struct dc_link_settings get_max_link_cap(struct dc_link *link)
* account for lttpr repeaters cap
* notes: repeaters do not snoop in the DPRX Capabilities addresses (3.6.3).
*/
- if (link->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) {
+ if (link->lttpr_mode != LTTPR_MODE_NON_LTTPR) {
if (link->dpcd_caps.lttpr_caps.max_lane_count < max_link_cap.lane_count)
max_link_cap.lane_count = link->dpcd_caps.lttpr_caps.max_lane_count;
--
2.38.1