EI_MEMSIZE
sc->sc_ie.sc_msize = EI_MEMSIZE;
#define EI_MEMBASE (0x1000000 - EI_MEMSIZE)
#define EI_NPAGES (EI_MEMSIZE / EI_PAGESIZE)
#define ei_atop(a) (((a) % EI_MEMSIZE) / EI_PAGESIZE)
#define EI_SCP_ADDR IE_SCP_ADDR % EI_MEMSIZE