Re:Fedora considers deprecating legacy BIOS
by babypuncher on Thursday April 21, 2022 @01:45PM
(#31112753)
I think FAT is a fair baseline. It can be implemented in a few dozen lines of code. Support for it is ubiquitous. It is not encumbered by any active patents. All the alternatives I have seen proposed are both considerably more complex and not ubiquitously supported.
So, just do FAT and be done with it. Adding other filesystems is just a waste of time because the ESP only needs to store a half dozen files or so.
13.3.1.1: "The EFI firmware must support the FAT32, FAT16, and FAT12 variants of the EFI file system"