https://bugs.freedesktop.org/show_bug.cgi?id=107154
--- Comment #7 from freedesktop.org@nentwig.biz --- Sure, attached. AMD staging kernel. I don't know how to tell whether DC=1 is really enabled, so I did two runs: one with amdgpu.dc=1 as boot parameter and one with /etc/modprobe.d/ on top of that.
Procedure was the same both times: - boot - X login - switch to console - sleep, wakeup - switch to X
The drm/amdgpu lines appear already in the console right after waking up, prior to switching to X.
This time "only" X crashed (could still move the pointer); at times the complete machine is dead, no switching to console and and no SSH.
(as a side note: is is normal that waking up on ryzen takes something on the order of 10-30s? I'm used to split second wakeups on Intel.)
HTH