diff options
| author | Martin Tsai <martin.tsai@amd.com> | 2021-06-08 13:48:32 +0800 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2021-06-21 17:45:14 -0400 |
| commit | 068312559d33d90b2802561df7bff35ed407cd73 (patch) | |
| tree | 27dc186e3a871b2c959bd61a7cb1078d244cb3e0 | |
| parent | 5d9e7fe8ef9b1c91a4821eef4533f4010e011117 (diff) | |
drm/amd/display: Clear lane settings after LTTPRs have been trained
[Why]
The voltage swing has to start from the minimum level when transmit TPS1 over
Main-Link in clock recovery sequence.
The lane settings from current design will inherit the existing VS/PE values
that could be adjusted by Repeater X, and to use the adjusted voltage swing level
in Repeater X-1 or DPRX could violate DP specs.
[How]
To reset VS from lane settings after LTTPRs have been trained to meet the requirement.
Signed-off-by: Martin Tsai <martin.tsai@amd.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Bindu Ramamurthy <bindu.r@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 4 |
1 files changed, 4 insertions, 0 deletions
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 a3eeb4cda2de..36a2dba54506 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 @@ -1664,6 +1664,7 @@ static enum link_training_result dp_perform_8b_10b_link_training( uint8_t repeater_cnt; uint8_t repeater_id; + uint8_t lane = 0; if (link->ctx->dc->work_arounds.lt_early_cr_pattern) start_clock_recovery_pattern_early(link, lt_settings, DPRX); @@ -1694,6 +1695,9 @@ static enum link_training_result dp_perform_8b_10b_link_training( repeater_training_done(link, repeater_id); } + + for (lane = 0; lane < (uint8_t)lt_settings->link_settings.lane_count; lane++) + lt_settings->lane_settings[lane].VOLTAGE_SWING = VOLTAGE_SWING_LEVEL0; } if (status == LINK_TRAINING_SUCCESS) { |