<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [Regression]Multiple monitors via DP TB dock detection/resolution/layout failure after Skylake->Coffeelake upgrade" href="https://bugs.freedesktop.org/show_bug.cgi?id=111179#c12">Comment # 12</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [Regression]Multiple monitors via DP TB dock detection/resolution/layout failure after Skylake->Coffeelake upgrade" href="https://bugs.freedesktop.org/show_bug.cgi?id=111179">bug 111179</a> from <a class="email" href="mailto:ville.syrjala@linux.intel.com" title="Ville Syrjala <ville.syrjala@linux.intel.com>"> Ville Syrjala</a> <pre>(In reply to Arcadiy Ivanov from <a href="show_bug.cgi?id=111179#c11">comment #11</a>) > Thanks for looking at this. > > Both Dell Precision 7510 (SKL) and Dell Precision 5540 (CFL) have the same > TB capabilities, TB3 ***HBR2***. It's true, with HBR2 they don't support > 2x4k@60Hz(**), but the point of filing this bug was somewhat different - > there was a change in behavior in monitor detection and resolution/refresh > rate setting. > > SKL was supporting 2x4k with auto-detection, which, given hardware > limitations, means that it was settling on 2x4k@30Hz mode all by itself. > When an upgrade was made to CFL, this auto-detection stopped working > properly - as you can see it tried to configure 2x4K@60Hz and failed, > without fallback to 2x4K@30Hz. Are you sure SKL used 30Hz? If it did then that was being done by some userspace component. The kernel driver never does stuff like that (it just more or less blindly tries to do what userspace asks).</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are the assignee for the bug.</li> <li>You are on the CC list for the bug.</li> </ul> </body> </html>