PIIX_PM_BASE
base = pci_conf_read(pa->pa_pc, pa->pa_tag, PIIX_PM_BASE);
pmbase = pci_conf_read(sc->sc_pc, sc->sc_pcitag, PIIX_PM_BASE);
pci_conf_write(sc->sc_pc, sc->sc_pcitag, PIIX_PM_BASE, pmbase);
pci_conf_write(sc->sc_pc, sc->sc_pcitag, PIIX_PM_BASE, pmbase);