[PATCH 5.10 031/104] drm/amd/display: Fix DPCD translation for LTTPR AUX_RD_INTERVAL

Greg Kroah-Hartman
2021-02-15T15:37:36Z

From: George Shen <george.shen@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@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>
Signed-off-by: Sasha Levin <sashal@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