Just tested with Ubuntu mainline kernel 6.2.0-060200rc5-generic. OpenCL with Arc 750 works with stock i915 module. No need for: specific OEM kernel, compile/DKMS, use of Intel repositories. On Ubuntu all that needs to be done is apt install intel-opencl-icd.
$ clinfo -l
Platform #0: Intel(R) OpenCL HD Graphics
`-- Device #0: Intel(R) Graphics [0x56a1]
$ darktable-cltest
[dt_get_sysresource_level] switched to 2 as `large'
total mem: 32003MB
mipmap cache: 4000MB
available mem: 21877MB
singlebuff: 500MB
OpenCL tune mem: WANTED
OpenCL pinned: OFF
[opencl_init] opencl related configuration options:
[opencl_init] opencl: ON
[opencl_init] opencl_scheduling_profile: 'very fast GPU'
[opencl_init] opencl_library: 'default path'
[opencl_init] opencl_device_priority: '*/!0,*/*/*/!0,*'
[opencl_init] opencl_mandatory_timeout: 400
[opencl_init] opencl library 'libOpenCL.so.1' found on your system and loaded
[opencl_init] found 1 platform
[opencl_init] found 1 device
[dt_opencl_device_init]
DEVICE: 0: 'Intel(R) Graphics [0x56a1]'
CANONICAL NAME: intelrgraphics0x56a1
PLATFORM NAME & VENDOR: Intel(R) OpenCL HD Graphics, Intel(R) Corporation
DRIVER VERSION: 1.0.0
DEVICE VERSION: OpenCL 3.0 NEO
DEVICE_TYPE: GPU
GLOBAL MEM SIZE: 7722 MB
MAX MEM ALLOC: 3861 MB
MAX IMAGE SIZE: 16384 x 16384
MAX WORK GROUP SIZE: 1024
MAX WORK ITEM DIMENSIONS: 3
MAX WORK ITEM SIZES: [ 1024 1024 1024 ]
ASYNC PIXELPIPE: NO
PINNED MEMORY TRANSFER: NO
MEMORY TUNING: WANTED
FORCED HEADROOM: 400
AVOID ATOMICS: NO
MICRO NAP: 250
ROUNDUP WIDTH: 16
ROUNDUP HEIGHT: 16
CHECK EVENT HANDLES: 128
PERFORMANCE: 1.460
TILING ADVANTAGE: 0.000
DEFAULT DEVICE: NO
KERNEL DIRECTORY: /usr/share/darktable/kernels
CL COMPILER OPTION: -cl-fast-relaxed-math
KERNEL LOADING TIME: 0.0171 sec
[opencl_init] OpenCL successfully initialized.
[opencl_init] here are the internal numbers and names of OpenCL devices available to darktable:
[opencl_init] 0 'Intel(R) Graphics [0x56a1]'
[opencl_init] FINALLY: opencl is AVAILABLE on this system.