AMD Mesa OpenCL not recognized.

[brucethemoose]

Running Arch Linux, KNLMeans does not recognize my AMD (integrated) GPU, even though clinfo does.

Looks like its a problem with the oclutils library. This is what I get from running its little example utility:

❯ ./OclUtilsExample
OpenCL: File locking mechanism enabled. Will probably fail if run under a queueing system.
-------------------------------------------------------------------------------------------------------------
OpenCL: Getting a list of platform(s)... done.
OpenCL: Initializing the 3 available platforms...
        (1/3) NVIDIA Corporation
        (2/3) Mesa
        (3/3) Mesa/X.org
OpenCL: Initialize platform "NVIDIA CUDA"'s device(s)
OpenCL: WARNING: Can't find a usable CPU!
OpenCL: Attempt to acquire lock on file /tmp/OpenCL_Platform0_Device0__NVIDIA_CUDA_NVIDIA_GeForce_RTX_2060_with_Max_Q_Design.lck...Success!
ERROR: Unknown OpenCL platform "mesa"! Exiting.
fish: Job 1, './OclUtilsExample' terminated by signal SIGABRT (Abort)

And that looks like an issue of simply not recognizing "mesa" as a valid platform:

https://github.com/nbigaouette/oclutils/blob/183589c63d47c05a0304c92f9cbcf77994167563/src/OclUtils.cpp#L462-L474

EDIT: Doesn't seem to work with ROCM either.

I think this means AMD GPUs are incompatible with this on linux.