https://bugs.freedesktop.org/show_bug.cgi?id=109246
--- Comment #8 from Michel Dänzer michel@daenzer.net ---
From the Xorg log file:
[ 212.439] (II) AMDGPU(0): Allocate new frame buffer 1440x900 [ 212.439] (II) AMDGPU(0): => pitch 6144 bytes [ 212.639] (II) AMDGPU(0): Allocate new frame buffer 3360x1080 [ 212.639] (II) AMDGPU(0): => pitch 14336 bytes
This does look like there are hotplug events, and the HDMI output is considered disconnected for a moment.
(In reply to Alex Deucher from comment #5)
Some monitors poll inputs which sometimes causes the hpd pin to fire which looks like a hotplug event to the driver.
Any idea why this seems to only cause trouble with DC though?
(I was seeing similar symptoms with DC and an HDMI connection with Kaveri, I reported it to the DC developers internally a while ago; it's one reason why I'm currently not using DC on this machine)