U-Boot: EFI patches applied, and new bootefi command

Alexander Graf of SuSE has been adding EFI support to U-Boot.  He also just added a new boot loader command, ‘bootefi’, as well:

[PATCH v6 19/30] efi_loader: Add “bootefi” command

In order to execute an EFI application, we need to bridge the gap between U-Boot’s notion of executing images and EFI’s notion of doing the same. The best path forward IMHO here is to stick completely to the way U-Boot deals with payloads. You manually load them using whatever method to RAM and then have a simple boot command to execute them. So in our case, you would do

  # load mmc 0:1 $loadaddr grub.efi
  # bootefi $loadaddr

which then gets you into a grub shell. Fdt information known to U-boot via the fdt addr command is also passed to the EFI payload.

Tom Rini of the U-Boot project also just posted a message saying that the EFI patches have been mostly applied:

EFI loader support largely enabled

What I mean by the subject is that with the EFI loader patches enabled U-Boot itself (not SPL) now includes the EFI loader and required bits on ARM/aarch64.  This is in general I think a good thing.  I’ve however disabled it on a few boards due to size constraints.  This is an average gain of ~12KiB in U-Boot proper.  I fully expect a number of platform patches opting out of this support due to it just not being a real usecase and I am agreeable to talking about making it not enabled by default.  So, lets kick things off.

For more information, see the U-Boot sources or mailing list archives:


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