Re: Can't boot GNU Mach with efi

[Paul Dufresne]

https://help.ubuntu.com/community/UEFIBooting
is a good introduction to booting on UEFI with Grub.

They say: 
"If you have a non-Mac UEFI system, then you have a x86_64 (aka 64-bit) UEFI 
2.x firmware. "
But I did saw non-MAC UEFI which was 32 bit on relatively old laptops.

Type the following command in a MacOS terminal : ioreg -l -p IODeviceTree | 
grep firmware-abi
Which should show either EFI32 or EFI64.

Later in that document:
Using Apple bootloader itself (safest option)
You need to use the following naming convention for grub.efi :
EFI
Bootloader path and filename
32-bit
/EFI/BOOT/BOOTIA32.EFI

64-bit
/EFI/BOOT/BOOTX64.EFI

Also, about not having a console in GNUMach...

UEFI have their own drivers, written in a virtual machine (Describe in 
Appendice J of [1]).

When you begin in UEFI, you get the EFI_SYSTEM_TABLE (section 4.2) where you 
get handles to:
*ConIn (Console Input) and *ConOut (Console Output), that is describe more in 
chapter 12,
and Appendix B of [1].

[1]: https://uefi.org/sites/default/files/resources/UEFI_Spec_2_8_A_Feb14.pdf
taken from: https://www.uefi.org/specifications/

The question is... how to we get the EFI_SYSTEM_TABLE, that was read by 
BOOTX64.EFI (which I believe is part of Grub binary package)...
or is there an other way to get it again?