macOS support

[MOZGIII]

macOS support can be implemented via nvram command, and I'd love to add support macOS in my app.

[alixinne]

Without access to Apple hardware, we should at least find some sample output of nvram as well as its expected behavior so we could test the backend against that mock version, before adding it to the crate.

[iTrooz]

I'd like to try my hand at this, would you accept a PR ?

[MOZGIII]

Sure (ops, nvm, I don't have access to accept PRs here) :D

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There are now two flavors of macOS hardware, with Intel and Apple CPUs. The boot process is very different. @iTrooz which one do you plan to work on?

[alixinne]

I'd like to try my hand at this, would you accept a PR ?

Sure thing, I don't have much time to actively develop this project (as in, add new features and stuff) but I can review PRs no problem. The whole CI/release process is setup so any changes would get released as soon as they're merged.

[iTrooz]

There are now two flavors of macOS hardware, with Intel and Apple CPUs. The boot process is very different. @iTrooz which one do you plan to work on?

Honestly, I have no idea. I just liked the idea of tinkering with MacOS's internals.
You seem to have some insight, so if you have any documentation links to share, please do so ^^

[MOZGIII]

I did my research on this back in the day, and what I got to was the idea of running the nvram from the CLI and point things through that. Very suboptimal, but would do the trick. However, it was not clear if this was necessary, since macos has a built-in next boot switcher - that is, had on intel macs, but not on the arm macs as far as I can tell. Anyhow, my level of understanding is very surface here, probably the best source would be to look at asahi (or possibly even mainline) linux to see if the efi vars make sense at all on arm macs.

I suggest checking out the following:

• https://github.com/AsahiLinux/docs/wiki/Distro:Boot-process-guide
• https://github.com/AsahiLinux/docs/wiki/Tethered-Boot-Setup-%28For-Developers%29
• https://github.com/AsahiLinux/docs/wiki/U-Boot (maybe not relevant, but maybe it is)