"SeaUBoot" ROM images now available in Libreboot. This will feature in the next release.
Implemented in this patch:
https://browse.libreboot.org/lbmk.git/commit/?id=7d1fd1cc6a176d15d8a938cd0df9868cbbb86d8f
These images have SeaBIOS, GRUB and U-Boot. Boot anything you want in SeaBIOS by pressing ESC to access the menu; this includes GRUB, which is still in flash.
With SeaUBoot, a bootorder file makes SeaBIOS boot U-Boot from flash first, unless interrupted.
Same concept as SeaGRUB.
Nice UEFI-first setup.
Gonna try *UEFI* OpenBSD. Installation and booting.