<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - Intel HD 520 failed to train DP when connected with a external monitor" href="https://bugs.freedesktop.org/show_bug.cgi?id=93578#c3">Comment # 3</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - Intel HD 520 failed to train DP when connected with a external monitor" href="https://bugs.freedesktop.org/show_bug.cgi?id=93578">bug 93578</a> from <a class="email" href="mailto:mcq@astranis.com" title="John McCorquodale <mcq@astranis.com>"> John McCorquodale</a> <pre>Same error here, black screen. It's a Dell UP2414Q which is a 2-tile DP1.2 MTS device, i7-6700K. The UP2414Q is known to be finicky about sinking; this is an A01 rev of that display, which has fewer problems in that regard than the highly dubious A00 rev (i.e. I don't think we can immediately blame the display). Works okay (at least once) in non-MTS DP1.1 mode as a single 3840x2160 30Hz device. Happy to be somebody's debug minion; feel free to contact me directly. ---xrandr--- P1-8 connected 1920x2160+0+0 (normal left inverted right x axis y axis) 527mm x 296mm 1920x2160 59.99*+ DP1-9 connected 1920x2160+0+0 (normal left inverted right x axis y axis) 527mm x 296mm 1920x2160 59.99*+ 1920x1200 59.88 1920x1080 60.00 ... ---dmesg--- [ 163.467351] [drm:intel_dp_link_training_channel_equalization [i915]] *ERROR* failed to train DP, aborting [ 163.606349] [drm:intel_dp_link_training_channel_equalization [i915]] *ERROR* failed to train DP, aborting [ 163.719993] [drm:intel_dp_link_training_channel_equalization [i915]] *ERROR* failed to train DP, aborting [ 163.784642] [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in ddi_pl l_sel (expected 0x00000000, found 0x00000001) [ 163.784647] [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in shared _dpll (expected -1, found 0) [ 163.784651] [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in dpll_h w_state.ctrl1 (expected 0x00000000, found 0x00000003) [ 163.784654] [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in base.a djusted_mode.crtc_clock (expected 277250, found 138624) [ 163.784658] [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in port_c lock (expected 540000, found 270000) ... [several dump_stack] ... [ 167.475902] [drm:intel_dp_link_training_channel_equalization [i915]] *ERROR*</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> <li>You are the QA Contact for the bug.</li> <li>You are on the CC list for the bug.</li> </ul> </body> </html>