ICS_ARCIN_V6_INTROFFSET_1
writeb(0, base + ICS_ARCIN_V6_INTROFFSET_1);
readb(state->irq_port + ICS_ARCIN_V6_INTROFFSET_1);
(ap->port_no ? ICS_ARCIN_V6_INTROFFSET_2 : ICS_ARCIN_V6_INTROFFSET_1);