isa_mtb
#define isa_readb(p) in_8(isa_mtb((unsigned long)(p)))
#define isa_writeb(val,p) out_8(isa_mtb((unsigned long)(p)),(val))
#define isa_rom_readb(p) rom_in_8(isa_mtb((unsigned long)(p)))
#define isa_rom_writeb(val, p) rom_out_8(isa_mtb((unsigned long)(p)), (val))