MV_INT_CAUSE1
cause1 = pci_dw_dbi_rd4(sc->dev, MV_INT_CAUSE1);
pci_dw_dbi_wr4(sc->dev, MV_INT_CAUSE1, cause1);
pci_dw_dbi_wr4(sc->dev, MV_INT_CAUSE1, 0xFFFFFFFF);
cause1 = pci_dw_dbi_rd4(sc->dev, MV_INT_CAUSE1);
pci_dw_dbi_wr4(sc->dev, MV_INT_CAUSE1, cause1);