Since you need to
call it in early stage, it is not
good to put in pc80.
I don't think this is a problem... There is other code in src/pc80 that
runs in early stage, like mc4168rtc_early.c and usbdebug_direct_serial.c
src/pc80 seems like a better place than src/arch/i386, since the other
pc legacy stuff like rtc, isa-dma, serial, interrupt controller and
timer are there, too.