A couple of years ago I assembled a Blackbird into a case with a Radeon RX580 GPU, installed a version of Fedora Linux and I don't recall having to do anything special to make it work.
This week I dropped the Radeon back into the Blackbird which now runs Fedora 35 Workstation, and it doesn't produce video.
uname -r
5.14.16-301.fc35.ppc64le
The card is seen along with the aspeed one:
lspci | grep VGA
0000:01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/570X/580/580X/590] (rev e7)
0005:02:00.0 VGA compatible controller: ASPEED Technology, Inc. ASPEED Graphics Family (rev 41)
And the kernel is loading modules for it:
lsmod | grep -i amdgpu
amdgpu 8257536 1
drm_ttm_helper 262144 3 drm_vram_helper,ast,amdgpu
ttm 327680 3 drm_vram_helper,amdgpu,drm_ttm_helper
mfd_core 327680 1 amdgpu
gpu_sched 327680 1 amdgpu
i2c_algo_bit 262144 2 ast,amdgpu
drm_kms_helper 524288 5 drm_vram_helper,ast,amdgpu
drm 851968 10 gpu_sched,drm_kms_helper,drm_vram_helper,ast,amdgpu,drm_ttm_helper,ttm
i2c_core 327680 8 drm_kms_helper,i2c_algo_bit,at24,ast,amdgpu,i2c_opal,regmap_i2c,drm
The only clue I have found so far comes from dmesg, which says in part:
[ 121.619204] amdgpu 0000:01:00.0: [drm] Cannot find any crtc or sizes
[ 133.894384] amdgpu 0000:01:00.0: refused to change power state from D0 to D3hot
I don't recall seeing this in the past (though I may have and have just forgotten) but I wonder if someone could point me in the direction of what I'm missing to get this going?
Thanks,
MC