diff --git a/hw/ppce500_pci.c b/hw/ppce500_pci.c
index 0ece422446..960a5d0c60 100644
--- a/hw/ppce500_pci.c
+++ b/hw/ppce500_pci.c
@@ -89,6 +89,7 @@ static uint32_t pci_reg_read4(void *opaque, target_phys_addr_t addr)
     PPCE500PCIState *pci = opaque;
     unsigned long win;
     uint32_t value = 0;
+    int idx;
 
     win = addr & 0xfe0;
 
@@ -97,18 +98,19 @@ static uint32_t pci_reg_read4(void *opaque, target_phys_addr_t addr)
     case PPCE500_PCI_OW2:
     case PPCE500_PCI_OW3:
     case PPCE500_PCI_OW4:
+        idx = (addr >> 5) & 0x7;
         switch (addr & 0xC) {
         case PCI_POTAR:
-            value = pci->pob[(addr >> 5) & 0x7].potar;
+            value = pci->pob[idx].potar;
             break;
         case PCI_POTEAR:
-            value = pci->pob[(addr >> 5) & 0x7].potear;
+            value = pci->pob[idx].potear;
             break;
         case PCI_POWBAR:
-            value = pci->pob[(addr >> 5) & 0x7].powbar;
+            value = pci->pob[idx].powbar;
             break;
         case PCI_POWAR:
-            value = pci->pob[(addr >> 5) & 0x7].powar;
+            value = pci->pob[idx].powar;
             break;
         default:
             break;
@@ -118,18 +120,19 @@ static uint32_t pci_reg_read4(void *opaque, target_phys_addr_t addr)
     case PPCE500_PCI_IW3:
     case PPCE500_PCI_IW2:
     case PPCE500_PCI_IW1:
+        idx = ((addr >> 5) & 0x3) - 1;
         switch (addr & 0xC) {
         case PCI_PITAR:
-            value = pci->pib[(addr >> 5) & 0x3].pitar;
+            value = pci->pib[idx].pitar;
             break;
         case PCI_PIWBAR:
-            value = pci->pib[(addr >> 5) & 0x3].piwbar;
+            value = pci->pib[idx].piwbar;
             break;
         case PCI_PIWBEAR:
-            value = pci->pib[(addr >> 5) & 0x3].piwbear;
+            value = pci->pib[idx].piwbear;
             break;
         case PCI_PIWAR:
-            value = pci->pib[(addr >> 5) & 0x3].piwar;
+            value = pci->pib[idx].piwar;
             break;
         default:
             break;
@@ -160,6 +163,7 @@ static void pci_reg_write4(void *opaque, target_phys_addr_t addr,
 {
     PPCE500PCIState *pci = opaque;
     unsigned long win;
+    int idx;
 
     win = addr & 0xfe0;
 
@@ -171,18 +175,19 @@ static void pci_reg_write4(void *opaque, target_phys_addr_t addr,
     case PPCE500_PCI_OW2:
     case PPCE500_PCI_OW3:
     case PPCE500_PCI_OW4:
+        idx = (addr >> 5) & 0x7;
         switch (addr & 0xC) {
         case PCI_POTAR:
-            pci->pob[(addr >> 5) & 0x7].potar = value;
+            pci->pob[idx].potar = value;
             break;
         case PCI_POTEAR:
-            pci->pob[(addr >> 5) & 0x7].potear = value;
+            pci->pob[idx].potear = value;
             break;
         case PCI_POWBAR:
-            pci->pob[(addr >> 5) & 0x7].powbar = value;
+            pci->pob[idx].powbar = value;
             break;
         case PCI_POWAR:
-            pci->pob[(addr >> 5) & 0x7].powar = value;
+            pci->pob[idx].powar = value;
             break;
         default:
             break;
@@ -192,18 +197,19 @@ static void pci_reg_write4(void *opaque, target_phys_addr_t addr,
     case PPCE500_PCI_IW3:
     case PPCE500_PCI_IW2:
     case PPCE500_PCI_IW1:
+        idx = ((addr >> 5) & 0x3) - 1;
         switch (addr & 0xC) {
         case PCI_PITAR:
-            pci->pib[(addr >> 5) & 0x3].pitar = value;
+            pci->pib[idx].pitar = value;
             break;
         case PCI_PIWBAR:
-            pci->pib[(addr >> 5) & 0x3].piwbar = value;
+            pci->pib[idx].piwbar = value;
             break;
         case PCI_PIWBEAR:
-            pci->pib[(addr >> 5) & 0x3].piwbear = value;
+            pci->pib[idx].piwbear = value;
             break;
         case PCI_PIWAR:
-            pci->pib[(addr >> 5) & 0x3].piwar = value;
+            pci->pib[idx].piwar = value;
             break;
         default:
             break;