From 61ce46d37dbc8359cc96ef91c2c8232c5e417456 Mon Sep 17 00:00:00 2001
From: Jimmy Kizito <Jimmy.Kizito@amd.com>
Date: Wed, 7 Apr 2021 18:56:19 -0400
Subject: drm/amd/display: Train DPIA links with fallback
Git-commit: edfb2693471f593856df915cd24c1b62ffaf978c
Patch-mainline: v5.16-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 & How]
Conventional links are trained with fallback during sink detection.
Have DPIA links trained with fallback too.

Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Wayne Lin <Wayne.Lin@amd.com>
Acked-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Jimmy Kizito <Jimmy.Kizito@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.c    | 6 ++++++
 drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 4 ++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index 1c397d5551ba..6b5ddf0a29c1 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -1862,6 +1862,12 @@ static enum dc_status enable_link_dp(struct dc_state *state,
 	/* get link settings for video mode timing */
 	decide_link_settings(stream, &link_settings);
 
+	/* Train with fallback when enabling DPIA link. Conventional links are
+	 * trained with fallback during sink detection.
+	 */
+	if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA)
+		do_fallback = true;
+
 #if defined(CONFIG_DRM_AMD_DC_DCN)
 	if (dp_get_link_encoding_format(&link_settings) == DP_128b_132b_ENCODING &&
 			pipe_ctx->stream->signal == SIGNAL_TYPE_DISPLAY_PORT) {
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 13bf1d5ffb25..eb320790523e 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
@@ -2406,9 +2406,9 @@ bool perform_link_training_with_retries(
 			dc_link_dp_perform_link_training_skip_aux(link, &current_setting);
 			return true;
 		} else {
-			if (link->is_dig_mapping_flexible)
+			if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA)
 				status = dc_link_dpia_perform_link_training(link,
-									    link_setting,
+									    &current_setting,
 									    skip_video_pattern);
 			else
 				status = dc_link_dp_perform_link_training(link,
-- 
2.38.1