Hi,
I have a 6800XT and a RX550 in my system. I want the system to use RX550 and only use the 6800XT when called with DRI_PRIME=1. With the automatic config everything in linux itself works fine.
I am currently trying to get a custom xorg.conf to work. Reason for that is that I need a bit more control over witch graphics card is claimed to make it pass-through to a kvm. Currently I am at the step to get the 6800XT ready to be passed through. (I use this as a template: https://www.mups.co.uk/post/2018/08/seamless-gpu-pass-through-on-linux/ )
Having the config like this works fine as well:
# RX550
Section "Device"
Identifier "amdgpu1"
Driver "amdgpu"
# BusID "PCI:e@0:0:0"
EndSection
# RX6800XT
Section "Device"
Identifier "amdgpu2"
Driver "amdgpu"
# BusID "PCI:d@0:0:0"
EndSection
But when I uncomment the BusID-Option XOrg does not start and shows this error in the Xorg.log:
[ 10.527] ABI class: X.Org Video Driver, version 24.1
[ 10.527] (II) AMDGPU: Driver for AMD Radeon:
All GPUs supported by the amdgpu kernel driver
[ 10.537] (EE) No devices detected.
[ 10.537] (EE)
Fatal server error:
[ 10.537] (EE) no screens found(EE)
[ 10.537] (EE)
(Full log: https://pastebin.com/mtdNm9pN)
I also tried a lot of stuff of setting the Screen and Layout manually (Full Config I tried https://pastebin.com/de2JeYEM), but the culprit seems to be the BusID. So it would stand to reason that I have goofed up there and put the wrong values in. But when I check lspci this is the output there:
⋊> ~ lspci | grep "VGA" 12:55:34
0d:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Navi 21 [Radeon RX 6800/6800 XT / 6900 XT] (rev c1)
0e:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Lexa PRO [Radeon 540/540X/550/550X / RX 540X/550/550X] (rev c7)
I am running out of things to consider what the culprit could be. Can anybody give me a hint where I am going wrong?