diff --git a/hw/isa/piix4.c b/hw/isa/piix4.c
index 1d04fb6a55..18aa24424f 100644
--- a/hw/isa/piix4.c
+++ b/hw/isa/piix4.c
@@ -74,6 +74,31 @@ static void piix4_set_irq(void *opaque, int irq_num, int level)
     }
 }
 
+static int pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
+{
+    int slot;
+
+    slot = PCI_SLOT(pci_dev->devfn);
+
+    switch (slot) {
+    /* PIIX4 USB */
+    case 10:
+        return 3;
+    /* AMD 79C973 Ethernet */
+    case 11:
+        return 1;
+    /* Crystal 4281 Sound */
+    case 12:
+        return 2;
+    /* PCI slot 1 to 4 */
+    case 18 ... 21:
+        return ((slot - 18) + irq_num) & 0x03;
+    /* Unknown device, don't do any translation */
+    default:
+        return irq_num;
+    }
+}
+
 static void piix4_isa_reset(DeviceState *dev)
 {
     PIIX4State *d = PIIX4_PCI_DEVICE(dev);
@@ -266,31 +291,6 @@ static void piix4_register_types(void)
 
 type_init(piix4_register_types)
 
-static int pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
-{
-    int slot;
-
-    slot = PCI_SLOT(pci_dev->devfn);
-
-    switch (slot) {
-    /* PIIX4 USB */
-    case 10:
-        return 3;
-    /* AMD 79C973 Ethernet */
-    case 11:
-        return 1;
-    /* Crystal 4281 Sound */
-    case 12:
-        return 2;
-    /* PCI slot 1 to 4 */
-    case 18 ... 21:
-        return ((slot - 18) + irq_num) & 0x03;
-    /* Unknown device, don't do any translation */
-    default:
-        return irq_num;
-    }
-}
-
 DeviceState *piix4_create(PCIBus *pci_bus, ISABus **isa_bus, I2CBus **smbus)
 {
     PIIX4State *s;