CAUTION: I HAVE NOT TRIED THIS SO PROCEED AT YOUR OWN RISK. READ THE INSTRUCTIONS IN THE INSTRUCTION LINK BELOW.
This is “today’s” solution. It will most likely change later.
you will have to
cd to where your driver download is, i.e., $HOME/Downloads
To install 5.4.0-54 do next:
sudo apt install linux-image-5.4.0-54-generic linux-headers-5.4.0-54-generic linux-modules-extra-5.4.0-54-generic
then reboot to 5.4.0-54
sudo apt remove linux-image-5.4.0-56-generic linux-image-unsigned-5.4.0-56-generic
(unsigned mentioned here because it tryed to install it for me by some reason.. it just helped)
sudo apt autoremove
then go to /usr/src and remove linux-headers-5.4.0-56-generic and inux-headers-5.4.0-56 (if any of them are there)
now you can
cd into the directory created by “winding the tar file” – $HOME/Download/driver_directory (noted above)
sudo ./amdgpu-install -y