PHN_IRQCTL
iowrite32(0, pht->caddr + PHN_IRQCTL);
ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
iowrite32(0, pht->caddr + PHN_IRQCTL);
ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */
iowrite32(0, dev->caddr + PHN_IRQCTL);
ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
iowrite32(0, dev->caddr + PHN_IRQCTL);
iowrite32(0x43, dev->caddr + PHN_IRQCTL);
ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */
iowrite32(0, dev->caddr + PHN_IRQCTL);
ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */