Xorg fails after update system to 16.0

Hello Matthias,

> # kldload amdgpu
> (PANIC)
> 
> Loading amdgpu.ko (which would be normally done via /etc/rc.conf) 
> PANICs
> the system. The lines in /var/log/messages after the kldload are:
> 
> ...
> Oct 18 22:33:16 ASUS-150 kernel: amdgpu: ATOM BIOS: 113-CEZANNE-018
> Oct 18 22:33:16 ASUS-150 kernel: drmn0: could not load firmware image
> 'amdgpu/green_sardine_sdma.bin'
> Oct 18 22:33:16 ASUS-150 kernel: [drm ERROR
> :amdgpu_sdma_init_microcode] SDMA: Failed to init firmware
> "amdgpu/green_sardine_sdma.bin"

I work with different kernels and I face similar issues occasionally. 
Looks like you have somehow intermixed modules for old and new kernel. 
Please check against which version of kernel each of your module is 
compiled (including firmware), then replace old ones.

I recently posted a simple 'kldinfo' tool for that purpose, you can get 
it from https://github.com/pointcheck/kldinfo.git

Example from my laptop running 13.5:

% kldinfo /boot/modules/amdgpu_green_sardine_sdma_bin.ko
MODULE: amdgpu_green_sardine_sdma_bin_fw DEPENDS: kernel                 
       VERSION: 1305000 1305000 1399999
MODULE: amdgpu_green_sardine_sdma_bin_fw DEPENDS: firmware               
       VERSION:       1       1       1
kldinfo: found 2 dependencies in 
/boot/modules/amdgpu_green_sardine_sdma_bin.ko

Hope this helps.

---
Regards,
Ruslan