This would presumably let x86 windows games run on ARM hardware.
This is almost certainly meant for the next Valve VR headset, but ARM has so much better power efficiency than x86 that a future ARM based Deck would be a huge improvement to battery life.
Also see this tweet:
VR games that have already secretly pushed Android ARM builds onto the Steam Store are ran via Waydroid (androidARM to LinuxARM)
VR games that do not have an ARM build on Steam (windows x86) are being translated/emulated via ProtonARM and FEX
Edit: here’s gamingonlinux coverage of this info, includes some more information
True, but I feel like having to reroute x86 calls to ARM will produce more overhead than just Proton.
Depends on how it’s implemented. If they have a version of Proton that translates all x86 windows syscalls to ARM Linux, some operations could be extremely efficient.
There’s definitely got to be more overhead overall, though. Especially for devices with memory page sizes other than 4K, like the M-series Apple chips do (they use 16K as their page size), likely a VM will need to be sandwiched in there to ensure memory alignment. It’ll more fully be emulation and not just translation.