PCI_CB_IOBASE0
offs = PCI_CB_IOBASE0;
sc->sc_iobase[0] = pci_conf_read(pc, tag, PCI_CB_IOBASE0);
pci_conf_write(pc, tag, PCI_CB_IOBASE0, sc->sc_iobase[0]);
pci_conf_write(pc, tag, PCI_CB_IOBASE0, 0xffffffff);