diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c index f1cac74dd7f7..46bb7a855bc2 100644 --- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c @@ -409,9 +409,6 @@ static enum dc_link_rate get_lttpr_max_link_rate(struct dc_link *link) case LINK_RATE_HIGH3: lttpr_max_link_rate = link->dpcd_caps.lttpr_caps.max_link_rate; break; - default: - // Assume all LTTPRs support up to HBR3 to improve misbehaving sink interop - lttpr_max_link_rate = LINK_RATE_HIGH3; } if (link->dpcd_caps.lttpr_caps.supported_128b_132b_rates.bits.UHBR20) @@ -2137,15 +2134,19 @@ struct dc_link_settings dp_get_max_link_cap(struct dc_link *link) * notes: repeaters do not snoop in the DPRX Capabilities addresses (3.6.3). */ if (dp_is_lttpr_present(link)) { - if (link->dpcd_caps.lttpr_caps.max_lane_count < max_link_cap.lane_count) - max_link_cap.lane_count = link->dpcd_caps.lttpr_caps.max_lane_count; - lttpr_max_link_rate = get_lttpr_max_link_rate(link); - if (lttpr_max_link_rate < max_link_cap.link_rate) - max_link_cap.link_rate = lttpr_max_link_rate; + /* Some LTTPR devices do not report valid DPCD revisions, if so, do not take it's link cap into consideration. */ + if (link->dpcd_caps.lttpr_caps.revision.raw >= DPCD_REV_14) { + if (link->dpcd_caps.lttpr_caps.max_lane_count < max_link_cap.lane_count) + max_link_cap.lane_count = link->dpcd_caps.lttpr_caps.max_lane_count; + lttpr_max_link_rate = get_lttpr_max_link_rate(link); - if (!link->dpcd_caps.lttpr_caps.supported_128b_132b_rates.bits.UHBR13_5) - is_uhbr13_5_supported = false; + if (lttpr_max_link_rate < max_link_cap.link_rate) + max_link_cap.link_rate = lttpr_max_link_rate; + + if (!link->dpcd_caps.lttpr_caps.supported_128b_132b_rates.bits.UHBR13_5) + is_uhbr13_5_supported = false; + } DC_LOG_HW_LINK_TRAINING("%s\n Training with LTTPR, max_lane count %d max_link rate %d \n", __func__, |