On Thu, 27 Jan 2022, Ville Syrjälä ville.syrjala@linux.intel.com wrote:
On Tue, Jan 25, 2022 at 07:03:43PM +0200, Jani Nikula wrote:
<snip> > +static bool > +intel_dp_128b132b_lane_cds(struct intel_dp *intel_dp, > + const struct intel_crtc_state *crtc_state, > + int lttpr_count) > +{ > + struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base; > + struct drm_i915_private *i915 = to_i915(encoder->base.dev); > + u8 link_status[DP_LINK_STATUS_SIZE]; > + unsigned long deadline; > + > + if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TRAINING_PATTERN_SET, > + DP_TRAINING_PATTERN_2_CDS) != 1) { > + drm_err(&i915->drm, > + "[ENCODER:%d:%s] Failed to start 128b/132b TPS2 CDS\n", > + encoder->base.base.id, encoder->base.name); > + return false; > + } > + > + deadline = jiffies + msecs_to_jiffies((lttpr_count + 1) * 20); > + for (;;) { > + usleep_range(2000, 3000); > + > + if (drm_dp_dpcd_read_link_status(&intel_dp->aux, link_status) < 0) { > + drm_err(&i915->drm, > + "[ENCODER:%d:%s] Failed to read link status\n", > + encoder->base.base.id, encoder->base.name); > + return false; > + } > + > + if (drm_dp_128b132b_cds_interlane_align_done(link_status) && > + drm_dp_128b132b_lane_symbol_locked(link_status, crtc_state->lane_count)) {
I'm thinkin we want to check for both eq done and symbol locked here, just like we do with 8b10b.
I guess so, although I don't think the spec explicitly calls that out.
Fixed anyway.
drm_dbg_kms(&i915->drm,"[ENCODER:%d:%s] CDS interlane align done\n",encoder->base.base.id, encoder->base.name);break;}if (drm_dp_128b132b_link_training_failed(link_status)) {intel_dp_dump_link_status(intel_dp, DP_PHY_DPRX, link_status);drm_err(&i915->drm,"[ENCODER:%d:%s] Downstream link training failure\n",encoder->base.base.id, encoder->base.name);return false;}if (time_after(jiffies, deadline)) {intel_dp_dump_link_status(intel_dp, DP_PHY_DPRX, link_status);drm_err(&i915->drm,"[ENCODER:%d:%s] CDS timeout\n",encoder->base.base.id, encoder->base.name);return false;}- }
- /* FIXME: Should DP_TRAINING_PATTERN_DISABLE be written first? */
- if (intel_dp->set_idle_link_train)
intel_dp->set_idle_link_train(intel_dp, crtc_state);- return true;
+}