was updating my coreboot tree, rebuild after rebuild, etc
pretty sure i nuked one of the flash chips on the motherboard by keeping the clip connected (and powered & all) while powercycling.
i got away with it before, but i guess i rolled snake eyes this time. those are the bad ones, right?
edit: now that i think about it, i was able to read both flash chips without issue, and reflash them. it might just be a firmware issue, after all!
Good chance you could read the number on the chip and find a replacement on AliExpress