It works on the huppyryzen pc after some patches.
But it didn'T work with a clean Ubuntu Mate 20.04.1 Live USB-Stick:
inxi -SMG
System:
Host: ubuntu-mate Kernel: 5.4.0-42-generic x86_64 bits: 64
Desktop: MATE 1.24.0 Distro: Ubuntu 20.04.1 LTS (Focal Fossa)
Machine:
Type: Desktop Mobo: ASUSTeK model: PRIME B350-PLUS v: Rev X.0x
serial: <superuser/root required> UEFI: American Megatrends v: 5602
date: 07/14/2020
Graphics:
Device-1: AMD Vega 10 XL/XT [Radeon RX Vega 56/64] driver: amdgpu
v: kernel
Display: x11 server: X.Org 1.20.8 driver: amdgpu,ati
unloaded: fbdev,modesetting,vesa
resolution: 2560x1440~60Hz, 3440x1440~60Hz
OpenGL:
renderer: Radeon RX Vega (VEGA10 DRM 3.35.0 5.4.0-42-generic LLVM 10.0.0)
v: 4.6 Mesa 20.0.8