Easily unlockable with WPInternals :)
> only the dead Windows phones
Marvell/SolidRun MACCHIATObin, SoftIron Overdrive, even the old Gigabyte boards with APM X-Gene have both U-Boot and EDK2 (TianoCore) firmwares available. I'm not even talking about big servers (ThunderX) :)
Heck, U-Boot itself can run EFI binaries, with network access for netbooting even — and it's good enough for FreeBSD/aarch64 to not even consider non-EFI booting methods.