[PATCH AUTOSEL 5.10 20/36] drm/amd/display: Fix DPCD translation for LTTPR AUX_RD_INTERVAL

Sasha Levin sashal at kernel.org
Mon Feb 8 17:57:50 UTC 2021


From: George Shen <george.shen at amd.com>

[ Upstream commit 2b6b7ab4b1cabfbee1af5d818efcab5d51d62c7e ]

[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 at amd.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu at amd.com>
Acked-by: Anson Jacob <Anson.Jacob at amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 6 +++---
 1 file changed, 3 insertions(+), 3 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 17e6fd8201395..32b73ea866737 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
@@ -877,13 +877,13 @@ 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;
-- 
2.27.0



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