From: Michael Strauss <michael.strauss@xxxxxxx> [ Upstream commit 10839ee6a977ed1f7d0f4deb29f2d7e5d1f2a9dd ] [WHY] Avoid race condition which puts LTTPR into bad state during UHBR LT. [HOW] Delay 30ms between starting UHBR TPS1 PHY output and sending TPS1 via DPCD. Reviewed-by: Wenjing Liu <wenjing.liu@xxxxxxx> Acked-by: Aurabindo Pillai <aurabindo.pillai@xxxxxxx> Signed-off-by: Michael Strauss <michael.strauss@xxxxxxx> Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- .../dc/link/hwss/link_hwss_hpo_fixed_vs_pe_retimer_dp.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/amd/display/dc/link/hwss/link_hwss_hpo_fixed_vs_pe_retimer_dp.c b/drivers/gpu/drm/amd/display/dc/link/hwss/link_hwss_hpo_fixed_vs_pe_retimer_dp.c index b621b97711b61..a7f5b0f6272ce 100644 --- a/drivers/gpu/drm/amd/display/dc/link/hwss/link_hwss_hpo_fixed_vs_pe_retimer_dp.c +++ b/drivers/gpu/drm/amd/display/dc/link/hwss/link_hwss_hpo_fixed_vs_pe_retimer_dp.c @@ -162,7 +162,12 @@ static void set_hpo_fixed_vs_pe_retimer_dp_link_test_pattern(struct dc_link *lin link_res->hpo_dp_link_enc->funcs->set_link_test_pattern( link_res->hpo_dp_link_enc, tp_params); } + link->dc->link_srv->dp_trace_source_sequence(link, DPCD_SOURCE_SEQ_AFTER_SET_SOURCE_PATTERN); + + // Give retimer extra time to lock before updating DP_TRAINING_PATTERN_SET to TPS1 + if (tp_params->dp_phy_pattern == DP_TEST_PATTERN_128b_132b_TPS1_TRAINING_MODE) + msleep(30); } static void set_hpo_fixed_vs_pe_retimer_dp_lane_settings(struct dc_link *link, -- 2.43.0
