(no title)
aystatic | 2 months ago
afaik you technically can, except that m1/m2 force pcie bars to be mapped as device memory (forbids unaligned r/w), so most gpu software (and drivers) that just issue memcpys to vram and expect the fabric to behave sanely will sigbus. it's possible to work around this, and some people indeed have with amdgpu, but it'd absolutely destroy performance to fix in the general case
so it doesn't really have anything to do with apple themselves blocking it but rather a niche implementation detail of the AS platform that's essentially an erratum
ece|2 months ago
There's also an Apple VP saying unified memory on AS doesn't leave room for DGPUs and separate VRAM.
I think this is more than just an erratum, even with newer chips. It's monopolistic behavior all too common nowadays.
aystatic|2 months ago
> There's also an Apple VP saying unified memory on AS doesn't leave room for DGPUs and separate VRAM
can you link to this? my intuition is that they're speaking on whether apple would include dgpus inside AS systems like they used to with nvidia and amd chips in macbooks, which i agree wouldn't make much sense atp