Booting on real hardware

[IsaacWoods]

I would like to get Pebble booting on a Thinkpad T490, just because that's what I have lying around. This unfortunately does not have a serial port AFAIK, so let's hope it has good GOP support at least.

So far, I've managed to get efiloader booting, but it crashes soon after because there are no load options specified.

Tasks:

• Don't panic if no load options are specified
• If no load options, use sensible defaults (e.g. assume kernel is at \kernel.elf) and that we should try and create a framebuffer of some reasonable size
• Test rendering to the framebuffer from inside the kernel
• Create some sort of gfxconsole layer to print stuff nicely inside the kernel. I don't think we'll get a userspace working on real hardware for a while, so I think this is a good first step.
• Build Butler infrastructure for creating an image on a USB stick or something (it would be nice for it to update existing images without needing to format the whole thing as well)

[IsaacWoods]

Firstly, UEFI booting and the GOP framebuffer seem to work well on the Thinkpad, so that's nice. However, efiloader currently fails to exit boot services, for an as-of-yet unknown reason. It never seems to actually return from this method, so it seems likely that something's not working correctly inside there.

After building up the gfxconsole layer, we could just add a bunch of logging in there to see where it fails. Falling back to not creating the framebuffer doesn't really work because we can't use ConsoleOut after successfully exiting boot services, so we'd never know.

What a shame it doesn't just have a serial port.