diff options
| author | Michael Strauss <michael.strauss@amd.com> | 2024-05-21 14:52:37 -0400 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2024-06-14 16:17:14 -0400 |
| commit | 82c421ba46ecd11b67e15a86ad382ab8a6ed1d5d (patch) | |
| tree | 60e5241499626c3b22a10a069a8299efead96a6a | |
| parent | 396477d9508e3c3cb95c9b6eb76346769efd961a (diff) | |
drm/amd/display: Add fallback defaults for invalid LTTPR DPCD caps
[WHY]
Some sinks are observed to return invalid LTTPR revision and/or invalid
LTTPR link rate capabilities.
[HOW]
Assume any LTTPR which reports invalid max link rate supports HBR3.
Don't validate LTTPR DPCD revision in dp_is_lttpr_present check.
Reviewed-by: George Shen <george.shen@amd.com>
Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Acked-by: Zaeem Mohamed <zaeem.mohamed@amd.com>
Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c | 19 |
1 files changed, 16 insertions, 3 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 964abccebdc6..1ff9876e3ca3 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 @@ -363,10 +363,10 @@ bool dp_is_128b_132b_signal(struct pipe_ctx *pipe_ctx) bool dp_is_lttpr_present(struct dc_link *link) { + /* Some sink devices report invalid LTTPR revision, so don't validate against that cap */ return (dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt) != 0 && link->dpcd_caps.lttpr_caps.max_lane_count > 0 && - link->dpcd_caps.lttpr_caps.max_lane_count <= 4 && - link->dpcd_caps.lttpr_caps.revision.raw >= 0x14); + link->dpcd_caps.lttpr_caps.max_lane_count <= 4); } /* in DP compliance test, DPR-120 may have @@ -399,7 +399,20 @@ static enum dc_link_rate get_link_rate_from_max_link_bw( static enum dc_link_rate get_lttpr_max_link_rate(struct dc_link *link) { - enum dc_link_rate lttpr_max_link_rate = link->dpcd_caps.lttpr_caps.max_link_rate; + + enum dc_link_rate lttpr_max_link_rate = LINK_RATE_UNKNOWN; + + switch (link->dpcd_caps.lttpr_caps.max_link_rate) { + case LINK_RATE_LOW: + case LINK_RATE_HIGH: + case LINK_RATE_HIGH2: + 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) lttpr_max_link_rate = LINK_RATE_UHBR20; |