ZTWOROMBASE
pg_proto = ZTWOROMBASE | PG_RW | PG_CI | PG_V;
RELOC(ZTWOROMADDR, vaddr_t) - ZTWOROMBASE + CUSTOMBASE;
#define NZTWOROMPG btoc(ZTWOROMTOP-ZTWOROMBASE)
((volatile void *)((u_int)ZTWOROMADDR - ZTWOROMBASE + (u_int)(pa)))
#define ztwopa(va) ((void *)(ZTWOROMBASE + (u_int)(va) - (u_int)ZTWOROMADDR))
(ZTWOROMADDR + ZTWOROMTOP - ZTWOROMBASE))
#define isztwopa(pa) ((u_int)(pa) >= ZTWOROMBASE && (u_int)(pa) <= ZTWOROMTOP)