SIU_IFCTL
siu_write32(base + SIU_IFCTL, 0x44440000);
ifctl = siu_read32(base + SIU_IFCTL);
siu_write32(base + SIU_IFCTL, ifctl);
siu_read32(base + SIU_IFCTL);
siu_write32(base + SIU_IFCTL, ifctl);