AMDGPU-PRO OpenCL with the open-source amdgpu kernel module

Update, 2021.01.20.

To install OpenCL part from AMDGPU-PRO, run:

    ./amdgpu-install --opencl=legacy --headless --no-dkms

Last tested with:

* As of AMDGPU-PRO 20.45-1188099-ubuntu-20.04 (and perhaps earlier), amdgpu-install does not honor --no-dkms option when run with --opencl=rocr, i.e. amdgpu-dkms is intalled and kernel module amdgpu.ko is compiled, replacing the one from Linux kernel tree.
* amdgpu-install may complain that it can't install, because this is not Ubuntu version expected. Edit /etc/os-release and replace Ubuntu version with what installer wants. After amdgpu-install completes /etc/os-release may be changed back.
* In Ubuntu 20.04 /dev/kfd is owned by root.render, not by Add user intended to use OpenCL to render group.

‘amdgpu’ is an open source Linux kernel module for AMD graphics. It is available in stock kernels starting with Linux 4.2. OpenCL support can be added by installing libraries from binary AMDGPU-PRO driver download, provided by AMD. AMDGPU-PRO itself only works with certain distributions/releases/kernel versions.

Check `lsmod` and /var/log/Xorg.log that you have amdgpu loaded and working.

Download AMDGPU-PRO package for your Linux distribution from

`tar -xvf ...` to upack the downloaded file and run:

    amdgpu-pro-install --compute    (see Update above)
which is for “compute only”, i.e. it will install only the following:

Run clinfo to check OpenCL support.
Or run darktable-cltest :)

May 2017. Šarūnas Burdulis.