INTMAP_IGN
vec = ((sc->sc_ign << INTMAP_IGN_SHIFT) & INTMAP_IGN) |
#define INTMAP_INR (INTMAP_IGN|INTMAP_INO)
#define INTIGN(x) ((x)&INTMAP_IGN)
sc->sc_ign = ma->ma_interrupts[0] & INTMAP_IGN;
ino |= schizo_pbm_readintr(pbm, mapoff) & INTMAP_IGN;
ino |= vec & INTMAP_IGN;