Created attachment 142991 [details]
Xorg.0.log with modesetting
+++ This bug was initially created as a clone of Bug #103953 +++
I have 3 Dell WQHD Screens (2560x1440) screens, connected to a Radeon RX580 (XFX, RX-580 GTS Black Edition, 1425 MHz 8GB).
My kernel is:
Linux edison 4.19.13-300.fc29.x86_64 #1 SMP Sat Dec 29 22:54:28 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
With the default boot settings, which enable amdgpu.dc, I am unable to get the native resolution on one of the three monitors.
If I disable amdgpu.dc on the kernel command line, I am able to get the native resolution on all three monitors.
I have attached the Xorg.0.conf.old from the startup with amdgpu.dc at the default setting, and Xorg.0.conf from the startup with amdgpu.dc=0.
I have also attached the initial part of the dmesg log from both boots:
dmesg-amdgpudcdefault.log : default amdgpu.dc setting (enabled)
dmesg-amdgpudc0.log : amdgpu.dc=0
The only relevant difference I see between the two is that with modesetting, I see the following errors:
edison kernel: amdgpu: [powerplay] Failed to retrieve minimum clocks.
edison kernel: amdgpu: [powerplay] Error in phm_get_clock_info
whereas without modesetting I do not see those errors.
Created attachment 142992 [details]
Xorg.0.log without modesetting
Created attachment 142993 [details]
dmesg with modesetting
Created attachment 142994 [details]
dmesg without modesetting