RS6000_BUS_SPACE_IO
data = inb(RS6000_BUS_SPACE_IO + MCA_POS_REG(reg) + (slot<<16));
outb(RS6000_BUS_SPACE_IO + MCA_POS_REG(reg) + (slot<<16), data);
mask = in32rb(RS6000_BUS_SPACE_IO + IOCC_IEE);
out32rb(RS6000_BUS_SPACE_IO + IOCC_IEE, mask);
mask = in32rb(RS6000_BUS_SPACE_IO + IOCC_IEE);
out32rb(RS6000_BUS_SPACE_IO + IOCC_IEE, mask);
out32rb(RS6000_BUS_SPACE_IO + IOCC_EOI(irq), 0x1); /* val is ignored */
out32rb(RS6000_BUS_SPACE_IO + IOCC_XIVR(irq), x);
rv = in32rb(RS6000_BUS_SPACE_IO + IOCC_IRR);