diff options
Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_dp_link_training.c')
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_dp_link_training.c | 44 |
1 files changed, 42 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c index 214c8858b8a9..86d58a4c8453 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c @@ -1170,6 +1170,41 @@ static bool intel_dp_can_link_train_fallback_for_edp(struct intel_dp *intel_dp, return true; } +static bool reduce_link_params_in_bw_order(struct intel_dp *intel_dp, + const struct intel_crtc_state *crtc_state, + int *new_link_rate, int *new_lane_count) +{ + int link_rate; + int lane_count; + int i; + + i = intel_dp_link_config_index(intel_dp, crtc_state->port_clock, crtc_state->lane_count); + for (i--; i >= 0; i--) { + intel_dp_link_config_get(intel_dp, i, &link_rate, &lane_count); + + if ((intel_dp->link.force_rate && + intel_dp->link.force_rate != link_rate) || + (intel_dp->link.force_lane_count && + intel_dp->link.force_lane_count != lane_count)) + continue; + + /* TODO: Make switching from UHBR to non-UHBR rates work. */ + if (drm_dp_is_uhbr_rate(crtc_state->port_clock) != + drm_dp_is_uhbr_rate(link_rate)) + continue; + + break; + } + + if (i < 0) + return false; + + *new_link_rate = link_rate; + *new_lane_count = lane_count; + + return true; +} + static int reduce_link_rate(struct intel_dp *intel_dp, int current_rate) { int rate_index; @@ -1231,8 +1266,13 @@ static bool reduce_link_params_in_rate_lane_order(struct intel_dp *intel_dp, static bool reduce_link_params(struct intel_dp *intel_dp, const struct intel_crtc_state *crtc_state, int *new_link_rate, int *new_lane_count) { - return reduce_link_params_in_rate_lane_order(intel_dp, crtc_state, - new_link_rate, new_lane_count); + /* TODO: Use the same fallback logic on SST as on MST. */ + if (intel_crtc_has_type(crtc_state, INTEL_OUTPUT_DP_MST)) + return reduce_link_params_in_bw_order(intel_dp, crtc_state, + new_link_rate, new_lane_count); + else + return reduce_link_params_in_rate_lane_order(intel_dp, crtc_state, + new_link_rate, new_lane_count); } static int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp, |