$ opencv_version --opencl

4.5.5
OpenCL Platforms:
    Clover
        dGPU: AMD Radeon RX 580 Series (POLARIS10, DRM 3.35.0, 13.1-RELEASE-p1, LLVM 13.0.1) (OpenCL 1.1 Mesa 21.3.8)
    Portable Computing Language
        CPU: AMD FX(tm)-8350 Eight-Core Processor            (OpenCL 1.2 pocl HSTR: pthread-x86_64-portbld-freebsd13.1-bdver2)
Current OpenCL device:
    Type = dGPU
    Name = AMD Radeon RX 580 Series (POLARIS10, DRM 3.35.0, 13.1-RELEASE-p1, LLVM 13.0.1)
    Version = OpenCL 1.1 Mesa 21.3.8
    Driver version = 21.3.8
    Address bits = 64
    Compute units = 36
    Max work group size = 256
    Local memory size = 32 KB
    Max memory allocation size = 3 GB 204 MB 819 KB 204 B
    Double support = Yes
    Half support = Yes
    Host unified memory = No
    Device extensions:
        cl_khr_byte_addressable_store
        cl_khr_global_int32_base_atomics
        cl_khr_global_int32_extended_atomics
        cl_khr_local_int32_base_atomics
        cl_khr_local_int32_extended_atomics
        cl_khr_int64_base_atomics
        cl_khr_int64_extended_atomics
        cl_khr_fp64
        cl_khr_extended_versioning
    Has AMD Blas = No
    Has AMD Fft = No
    Preferred vector width char = 16
    Preferred vector width short = 8
    Preferred vector width int = 4
    Preferred vector width long = 2
    Preferred vector width float = 4
    Preferred vector width double = 2
    Preferred vector width half = 0