I haven't found anything for the Vega 8 that would run on Linux.
I believe my really old Llano (2011) APU even had OpenCL support. It was a selling point at the time.
Not that it really matters for me, I only run wgpu compute stuff over Vulkan for my experiments.
For what it's worth, my Llano kept hanging up when I tried.
If you are on Windows... shrug.