<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_ASSIGNED " title="ASSIGNED - [GLK] no signal after switch resolution from 1080p@23.98" href="https://bugs.freedesktop.org/show_bug.cgi?id=105887#c65">Comment # 65</a> on <a class="bz_bug_link bz_status_ASSIGNED " title="ASSIGNED - [GLK] no signal after switch resolution from 1080p@23.98" href="https://bugs.freedesktop.org/show_bug.cgi?id=105887">bug 105887</a> from <a class="email" href="mailto:clinton.a.taylor@intel.com" title="Clinton Taylor <clinton.a.taylor@intel.com>"> Clinton Taylor</a> <pre> > I can confirm that applying > <a href="https://github.com/herrnst/ubuntu-bionic-kernel/commit/">https://github.com/herrnst/ubuntu-bionic-kernel/commit/</a> > 3d664ae3c8831a51139efbb5298fc27a1bee4950 "i915/glk: effectively disable > hdmi_12bps_possible()" does in fact solve the problem for me. It's my > understanding this is a workaround rather than a proper fix. If I can supply > logging, edid, or something that would be helpful towards a proper fix, > please let me know. > Thanks for the offer, however the failure doesn't actually show up in the logs. This appears to be a transcoder disable sequencing issue. The driver sequence has been confirmed as correct according to the Gemini Lake documentation. Why this happens only at 12bpc is still a mystery. A simple msleep(50); at the end of intel_ddi_disable_transcoder_func() appears to resolve the issue. This is also a W/A and not the final solution.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are on the CC list for the bug.</li> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>