APPLE_UNINORTH_GART_BASE
pci_conf_write(pa->pa_pc, pa->pa_tag, APPLE_UNINORTH_GART_BASE,
APPLE_UNINORTH_GART_BASE) & 0x0000ffff;
reg = pci_conf_read(sc->as_pc, sc->as_tag, APPLE_UNINORTH_GART_BASE)
pci_conf_write(sc->as_pc, sc->as_tag, APPLE_UNINORTH_GART_BASE, reg);