From 124155c0bd4a4ed822c1ba246bdf5123b42c3ad9 Mon Sep 17 00:00:00 2001
From: George Shen <george.shen@amd.com>
Date: Thu, 13 Apr 2023 19:03:59 -0400
Subject: drm/amd/display: Add w/a to disable DP dual mode on certain ports
[Why]
Certain ports on DCN3.2 configs do not properly populate the BIOS
info table flag to indicate DP dual mode is unsupported.
[How]
Add a workaround to disable DP dual mode on the ports with the missing
BIOS info table flag.
Reviewed-by: Michael Strauss <Michael.Strauss@amd.com>
Acked-by: Alan Liu <HaoPing.Liu@amd.com>
Signed-off-by: George Shen <george.shen@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---
drivers/gpu/drm/amd/display/dc/link/link_detection.c | 4 ++++
1 file changed, 4 insertions(+)
(limited to 'drivers/gpu/drm/amd/display/dc/link/link_detection.c')
diff --git a/drivers/gpu/drm/amd/display/dc/link/link_detection.c b/drivers/gpu/drm/amd/display/dc/link/link_detection.c
index a131e30fd7d6..17904de4f155 100644
--- a/drivers/gpu/drm/amd/display/dc/link/link_detection.c
+++ b/drivers/gpu/drm/amd/display/dc/link/link_detection.c
@@ -593,6 +593,10 @@ static bool detect_dp(struct dc_link *link,
/* DP SST branch */
link->type = dc_connection_sst_branch;
} else {
+ if (link->dc->debug.disable_dp_plus_plus_wa &&
+ link->link_enc->features.flags.bits.IS_UHBR20_CAPABLE)
+ return false;
+
/* DP passive dongles */
sink_caps->signal = dp_passive_dongle_detection(link->ddc,
sink_caps,
--
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