Hi

I experience random lock-ups when X starts.
It appears as system freeze just after X switch to graphic mode.
/var/log/messages contains: 

Mar 17 23:33:24 desktop64 kernel: [drm:amdgpu_atombios_dp_link_train] *ERROR*
displayport link status failed
Mar 17 23:33:24 desktop64 kernel: [drm:amdgpu_atombios_dp_link_train] *ERROR*
clock recovery failed
Mar 17 23:33:24 desktop64 kernel: [drm:amdgpu_atombios_dp_link_train] *ERROR*
displayport link status failed
Mar 17 23:33:24 desktop64 kernel: [drm:amdgpu_atombios_dp_link_train] *ERROR*
clock recovery failed
Mar 17 23:33:25 desktop64 kernel: [drm:amdgpu_atombios_dp_link_train] *ERROR*
displayport link status failed
Mar 17 23:33:25 desktop64 kernel: [drm:amdgpu_atombios_dp_link_train] *ERROR*
clock recovery failed
Mar 17 23:33:25 desktop64 kernel: [drm:amdgpu_atombios_dp_link_train] *ERROR*
displayport link status failed
Mar 17 23:33:25 desktop64 kernel: [drm:amdgpu_atombios_dp_link_train] *ERROR*
clock recovery failed

Tested under https://cgit.freedesktop.org/~agd5f/linux/log/?h=drm-next-4.17-wip
with amddc disabled. Video card - Radeon RX580