From: Alex Deucher <alexander.deucher@xxxxxxx>
This patch has been added to the 4.1 stable tree. If you have any
objections, please let us know.
===============
[ Upstream commit c8213a638f65bf487c10593c216525952cca3690 ]
When I fixed the dp rate selection in:
092c96a8ab9d1bd60ada2ed385cc364ce084180e
drm/radeon: fix dp link rate selection (v2)
I accidently dropped the special handling for NUTMEG
DP bridge chips. They require a fixed link rate.
Reviewed-by: Christian König <christian.koenig@xxxxxxx>
Reviewed-by: Ken Wang <Qingqing.Wang@xxxxxxx>
Reviewed-by: Harry Wentland <harry.wentland@xxxxxxx>
Tested-by: Ken Moffat <zarniwhoop@xxxxxxxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx>
---
drivers/gpu/drm/radeon/atombios_dp.c | 20 ++++++++++++++++----
1 file changed, 16 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/radeon/atombios_dp.c b/drivers/gpu/drm/radeon/atombios_dp.c
index 6d1ce09..7ac42d0 100644
--- a/drivers/gpu/drm/radeon/atombios_dp.c
+++ b/drivers/gpu/drm/radeon/atombios_dp.c
@@ -314,15 +314,27 @@ int radeon_dp_get_dp_link_config(struct drm_connector *connector,
unsigned max_lane_num = drm_dp_max_lane_count(dpcd);
unsigned lane_num, i, max_pix_clock;
- for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
- for (i = 0; i < ARRAY_SIZE(link_rates) && link_rates[i] <= max_link_rate; i++) {
- max_pix_clock = (lane_num * link_rates[i] * 8) / bpp;
+ if (radeon_connector_encoder_get_dp_bridge_encoder_id(connector) ==
+ ENCODER_OBJECT_ID_NUTMEG) {
+ for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
+ max_pix_clock = (lane_num * 270000 * 8) / bpp;
if (max_pix_clock >= pix_clock) {
*dp_lanes = lane_num;
- *dp_rate = link_rates[i];
+ *dp_rate = 270000;
return 0;
}
}
+ } else {
+ for (lane_num = 1; lane_num <= max_lane_num; lane_num <<= 1) {
+ for (i = 0; i < ARRAY_SIZE(link_rates) && link_rates[i] <= max_link_rate; i++) {
+ max_pix_clock = (lane_num * link_rates[i] * 8) / bpp;
+ if (max_pix_clock >= pix_clock) {
+ *dp_lanes = lane_num;
+ *dp_rate = link_rates[i];
+ return 0;
+ }
+ }
+ }
}
return -EINVAL;
--
2.5.0
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html