RX560: No picture on monitor (DP) after turning it off and on again
When I run KDE and turn off my monitor (connected by DisplayPort) and turn it on again, often (though not always) there will be no picture, just a single colour. The system is still accessible via SSH, so I can get a dmesg and reboot the PC. The dmesg (attached) first says “enabling link 0 failed: 15”, and then repeatedly spews out “flip_done timed out”s.
(This is the behaviour as of kernel 5.7.6; older kernels (and perhaps mesa, kwin, and firmware) showed different behaviour, e.g., monitor repeatedly going on and off, or no kernel message until I switched to another virtual console).
linux firmware: 20200619 Mesa: 20.0.8 KWin/Plasma: 5.18.5dmesg-monitor-on+off.bugzilla