diff options
Diffstat (limited to 'drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c')
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c | 14 |
1 files changed, 10 insertions, 4 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 2f11eaabb..289f5d133 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 @@ -412,12 +412,18 @@ static enum dc_link_rate get_cable_max_link_rate(struct dc_link *link) { enum dc_link_rate cable_max_link_rate = LINK_RATE_UNKNOWN; - if (link->dpcd_caps.cable_id.bits.UHBR10_20_CAPABILITY & DP_UHBR20) + if (link->dpcd_caps.cable_id.bits.UHBR10_20_CAPABILITY & DP_UHBR20) { cable_max_link_rate = LINK_RATE_UHBR20; - else if (link->dpcd_caps.cable_id.bits.UHBR13_5_CAPABILITY) + } else if (link->dpcd_caps.cable_id.bits.UHBR13_5_CAPABILITY) { cable_max_link_rate = LINK_RATE_UHBR13_5; - else if (link->dpcd_caps.cable_id.bits.UHBR10_20_CAPABILITY & DP_UHBR10) - cable_max_link_rate = LINK_RATE_UHBR10; + } else if (link->dpcd_caps.cable_id.bits.UHBR10_20_CAPABILITY & DP_UHBR10) { + // allow DP40 cables to do UHBR13.5 for passive or unknown cable type + if (link->dpcd_caps.cable_id.bits.CABLE_TYPE < 2) { + cable_max_link_rate = LINK_RATE_UHBR13_5; + } else { + cable_max_link_rate = LINK_RATE_UHBR10; + } + } return cable_max_link_rate; } |