4 ms·

Are we any closer to eGPU support for apple silicon?

by lamontcg 4y ago

mulderc 4y ago
I am skeptical that we will ever see that.
- fragmede 4y ago
  given that thunderbolt 3 is basically PCI, the only far fetched part would be having to write a 3rd party driver for the card. Given the high end businesses that exist in this world to work with video on the (eg Davinci on the iPad which was recently on the front page), combined with a demand for absolute highest end GPU performance, I think there's a business case for it. I wouldn't hold my breath waiting for it to be open source though.
  - smoldesu 4y ago
    Considering how little commercial support there is for basic GPU functionality on regular Linux, it's wishful thinking to expect a mysterious stranger to write this code for you. Especially for black-box hardware.
    - anthk 4y ago
      eGPU-s work on Linux. https://dataswamp.org/~solene/2021-12-05-nixos-egpu.html https://dataswamp.org/~solene/2021-12-05-nixos-egpu.html
      - smoldesu 4y ago
        I don't think this is generic eGPU support. AFAIK, Nvidia's render offloading is baked into their driver. Not sure if it has an AMD/Intel equivalent.
    - fragmede 4y ago
      The mysterious strangers I have in mind are Blackmagic Design, who write Davinci Resolve, for both Mac and Linux, and have the economic incentive to. They made $576 million in revenue last year so it's not that far fetched.
  - kcb 4y ago
    AMD gpu drivers are open source and already work on multiple platforms thanks to being part of the kernel and Mesa.
    - fragmede 4y ago
      The Linux kernel, yes. I was thinking of Darwin when I wrote that
rollcat 4y ago
Under macOS? Not until Apple acts, I guess.
- nicoburns 4y ago
  Presumably on linux this would "just work" (assuming drivers for the IO ports are written)?
  - leodriesch 4y ago
    Thunderbolt drivers are still WIP for Asahi so I’d assume eGPU support is still in the future.
amaranth 4y ago
I remember seeing this wasn't possible because the CPU uses 16KB page tables but GPUs only know how to work with 4KB but I can't find the reference anymore. I don't know if this just requires a change in VBIOS or a whole new GPU but it would mean it's up to nvidia, AMD, or Intel to make a Mac-specific GPU even though no Apple Silicon devices have PCIe slots so it would only be for the small minority of Mac users inside the small minority of eGPU users.

Are we any closer to eGPU support for apple silicon?

mulderc 4y ago

I am skeptical that we will ever see that.

fragmede 4y ago
given that thunderbolt 3 is basically PCI, the only far fetched part would be having to write a 3rd party driver for the card. Given the high end businesses that exist in this world to work with video on the (eg Davinci on the iPad which was recently on the front page), combined with a demand for absolute highest end GPU performance, I think there's a business case for it. I wouldn't hold my breath waiting for it to be open source though.
- smoldesu 4y ago
  Considering how little commercial support there is for basic GPU functionality on regular Linux, it's wishful thinking to expect a mysterious stranger to write this code for you. Especially for black-box hardware.
  - anthk 4y ago
    eGPU-s work on Linux. https://dataswamp.org/~solene/2021-12-05-nixos-egpu.html https://dataswamp.org/~solene/2021-12-05-nixos-egpu.html
    - smoldesu 4y ago
      I don't think this is generic eGPU support. AFAIK, Nvidia's render offloading is baked into their driver. Not sure if it has an AMD/Intel equivalent.
  - fragmede 4y ago
    The mysterious strangers I have in mind are Blackmagic Design, who write Davinci Resolve, for both Mac and Linux, and have the economic incentive to. They made $576 million in revenue last year so it's not that far fetched.
- kcb 4y ago
  AMD gpu drivers are open source and already work on multiple platforms thanks to being part of the kernel and Mesa.
  - fragmede 4y ago
    The Linux kernel, yes. I was thinking of Darwin when I wrote that

rollcat 4y ago

Under macOS? Not until Apple acts, I guess.

nicoburns 4y ago
Presumably on linux this would "just work" (assuming drivers for the IO ports are written)?
- leodriesch 4y ago
  Thunderbolt drivers are still WIP for Asahi so I’d assume eGPU support is still in the future.

amaranth 4y ago

I remember seeing this wasn't possible because the CPU uses 16KB page tables but GPUs only know how to work with 4KB but I can't find the reference anymore. I don't know if this just requires a change in VBIOS or a whole new GPU but it would mean it's up to nvidia, AMD, or Intel to make a Mac-specific GPU even though no Apple Silicon devices have PCIe slots so it would only be for the small minority of Mac users inside the small minority of eGPU users.