From: George Shen <george.shen@amd.com>
Date: Tue, 22 Dec 2020 19:05:41 +0000 (-0500)
Subject: drm/amd/display: Fix DPCD translation for LTTPR AUX_RD_INTERVAL
X-Git-Tag: howlett/maple/20220722_2~3755^2~5^2~28
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=a71c76ac7eea41cc45c2582f3dcf465e4ce2bca3;p=users%2Fjedix%2Flinux-maple.git

drm/amd/display: Fix DPCD translation for LTTPR AUX_RD_INTERVAL

[Why]
The translation between the DPCD value and the specified AUX_RD_INTERVAL
in the DP spec do not match.

[How]
Update values to match the spec.

Signed-off-by: George Shen <george.shen@amd.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Anson Jacob <Anson.Jacob@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---

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 4149b8771462..78857c97289d 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
@@ -892,13 +892,13 @@ static uint32_t translate_training_aux_read_interval(uint32_t dpcd_aux_read_inte
 
 	switch (dpcd_aux_read_interval) {
 	case 0x01:
-		aux_rd_interval_us = 400;
+		aux_rd_interval_us = 4000;
 		break;
 	case 0x02:
-		aux_rd_interval_us = 4000;
+		aux_rd_interval_us = 8000;
 		break;
 	case 0x03:
-		aux_rd_interval_us = 8000;
+		aux_rd_interval_us = 12000;
 		break;
 	case 0x04:
 		aux_rd_interval_us = 16000;