From: Cruise Hung Cruise.Hung@amd.com
[ Upstream commit 20c6168b3c8aadef7d2853c925d99eb546bd5e1c ]
[Why] When USB4 DP link training failed and fell back to lower link rate, the time slot calculation uses the verified_link_cap. And the verified_link_cap was not updated to the new one. It caused the wrong VC payload time-slot was allocated.
[How] Updated verified_link_cap with the new one from cur_link_settings after the LT completes successfully.
Reviewed-by: Jun Lei Jun.Lei@amd.com Acked-by: Wayne Lin wayne.lin@amd.com Signed-off-by: Cruise Hung Cruise.Hung@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 8 +++++++- 1 file changed, 7 insertions(+), 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 0c52506b367d..b4203a812c4b 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 @@ -2857,8 +2857,14 @@ bool perform_link_training_with_retries( skip_video_pattern);
/* Transmit idle pattern once training successful. */ - if (status == LINK_TRAINING_SUCCESS && !is_link_bw_low) + if (status == LINK_TRAINING_SUCCESS && !is_link_bw_low) { dp_set_hw_test_pattern(link, &pipe_ctx->link_res, DP_TEST_PATTERN_VIDEO_MODE, NULL, 0); + /* Update verified link settings to current one + * Because DPIA LT might fallback to lower link setting. + */ + link->verified_link_cap.link_rate = link->cur_link_settings.link_rate; + link->verified_link_cap.lane_count = link->cur_link_settings.lane_count; + } } else { status = dc_link_dp_perform_link_training(link, &pipe_ctx->link_res,