<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [KBL-R] DP link training failures lead to downgraded link parameters and resolution" href="https://bugs.freedesktop.org/show_bug.cgi?id=106223#c45">Comment # 45</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [KBL-R] DP link training failures lead to downgraded link parameters and resolution" href="https://bugs.freedesktop.org/show_bug.cgi?id=106223">bug 106223</a> from <a class="email" href="mailto:sushma.venkatesh.reddy@intel.com" title="Sushma <sushma.venkatesh.reddy@intel.com>"> Sushma</a> <pre>I am able to reproduce the issue on WHL device - when two 4K external monitors are connected, one 4K monitor is trained as 2K sometimes. I am connecting monitors using (USB-C to DP) USB-C and (HDMI to HDMI) HDMI cables. Here are the error messages that I am seeing: Line 2230: [ 841.162692] [drm:intel_dp_start_link_train] Channel equalization failed 5 times Line 2231: [ 841.162846] [drm:intel_dp_start_link_train] [CONNECTOR:90:DP-2] Link Training failed at link rate = 540000, lane count = 4 I was able to reproduce the issue on drm tip but it is very hard to reproduce like one out of 50 times. I tried the patch that is specified in the above comments and couldn't reproduce the bug. However, monitors take a longer time to train. Attached the log in my previous comment for more details.</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>