I’ve got Cycles Metal working on my M1 Max (32 core). It’s rather impressive as well.
I built Blender from source on my MBP15 i9 with VEGA 20 dGPU and applied the diff for the unreviewed patch. That gave me an X86 build of Blender that showed the Metal GPU options on the Intel Mac but alas didn’t render (kernel internal error).
I then tried to set the ARM flag to compile again but that didn’t work.
So as a last ditch I took the built X86 version over to my M1 Max and low and behold it renders on the GPU.
BMW in 43 seconds on the 32 core GPU - so not 30% faster than the 24 core version but it is an X86 build.
However, every scene I tried the live viewport performance is rather wonderful.
I’d never built Blender from source until today. I’ll keep this build now to play with until the proper one lands.
The only slightly difficult bit was getting the new patch added, which I did like this:
patch -p1 < ~/Developer/D13423.diff [downloaded the RAW file from the Dev site]
Then ran make again and that was it basically.