diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_dp.c | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 944b1449b7f9..16b7bf7af537 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -322,6 +322,24 @@ static int intel_dp_common_len_rate_limit(struct intel_dp *intel_dp, return 0; } +static bool intel_dp_link_params_valid(struct intel_dp *intel_dp) +{ + /* + * FIXME: we need to synchronize the current link parameters with + * hardware readout. Currently fast link training doesn't work on + * boot-up. + */ + if (intel_dp->link_rate == 0 || + intel_dp->link_rate > intel_dp->max_link_rate) + return false; + + if (intel_dp->lane_count == 0 || + intel_dp->lane_count > intel_dp_max_lane_count(intel_dp)) + return false; + + return true; +} + int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp, int link_rate, uint8_t lane_count) { @@ -4253,9 +4271,11 @@ intel_dp_check_link_status(struct intel_dp *intel_dp) if (!to_intel_crtc(intel_encoder->base.crtc)->active) return; - /* FIXME: we need to synchronize this sort of stuff with hardware - * readout. Currently fast link training doesn't work on boot-up. */ - if (!intel_dp->lane_count) + /* + * Validate the cached values of intel_dp->link_rate and + * intel_dp->lane_count before attempting to retrain. + */ + if (!intel_dp_link_params_valid(intel_dp)) return; /* Retrain if Channel EQ or CR not ok */ |