Julius Werner has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/37262 )
Change subject: util: cbfstool: Check alignment at build time ......................................................................
Patch Set 8:
Maybe the previous discussions in CB:33300 are useful?
Yeah, if we want to do explicit numbers I would vote for FMAP/512K or RO_FRID/1 instead of the %. I think the '/' stands for division and alignment is sort of a "is divisible by". For this here I suggested '%' to stand for modulo, because it's the "unaligned" sigil (as in "you may have a non-zero modulus for this section). But maybe I'm also widely overthinking all of this. :D (Also I think the '%' looks a bit better than '/' without another number behind it.)
I don't think we really need explicit numbers, though, I think that just makes this more complicated and more boilerplate-y again. In practice, we'll only ever care about 4K. The FMAP is sort of a "soft" requirement (make the alignment as large as makes sense for this platform), I don't think a hard constraint is very useful for that. In practice you usually just put in an explicit, largely-aligned offset for the FMAP section and then let the other RO sections flow around that.