[PATCH 5.19 42/72] drm/amd/display: Fix TDR eDP and USB4 display light up issue

From: Greg Kroah-Hartman
Date: Fri Sep 02 2022 - 08:54:21 EST


From: Meenakshikumar Somasundaram <meenakshikumar.somasundaram@xxxxxxx>

[ Upstream commit 30456ffa65469d1d2e5e1da05017e6728d24c11c ]

[Why]
After TDR recovery, eDP and USB4 display does not light up. Because
dmub outbox notifications are not enabled after dmub reload and link
encoder assignments for the streams are not cleared before dc state
reset.

[How]
- Dmub outbox notification is enabled after tdr recovery by issuing
inbox command to dmub.
- Link encoders for the streams are unassigned before dc state reset.

Reviewed-by: Jimmy Kizito <Jimmy.Kizito@xxxxxxx>
Reviewed-by: Jun Lei <Jun.Lei@xxxxxxx>
Acked-by: Tom Chung <chiahsuan.chung@xxxxxxx>
Signed-off-by: Meenakshikumar Somasundaram <meenakshikumar.somasundaram@xxxxxxx>
Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/amd/display/dc/core/dc.c | 1 +
drivers/gpu/drm/amd/display/dc/dc_link.h | 1 +
2 files changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index f144494011882..7d69341acca02 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -3783,6 +3783,7 @@ void dc_enable_dmub_outbox(struct dc *dc)
struct dc_context *dc_ctx = dc->ctx;

dmub_enable_outbox_notification(dc_ctx->dmub_srv);
+ DC_LOG_DC("%s: dmub outbox notifications enabled\n", __func__);
}

/**
diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h
index a3c37ee3f849c..f96f53c1bc258 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_link.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_link.h
@@ -337,6 +337,7 @@ enum dc_detect_reason {
DETECT_REASON_HPDRX,
DETECT_REASON_FALLBACK,
DETECT_REASON_RETRAIN,
+ DETECT_REASON_TDR,
};

bool dc_link_detect(struct dc_link *dc_link, enum dc_detect_reason reason);
--
2.35.1