diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c
index 83dedc878a..2223b985b2 100644
--- a/hw/pci-host/pnv_phb4.c
+++ b/hw/pci-host/pnv_phb4.c
@@ -1069,6 +1069,23 @@ static const TypeInfo pnv_phb4_iommu_memory_region_info = {
     .class_init = pnv_phb4_iommu_memory_region_class_init,
 };
 
+/*
+ * Return the index/phb-id of a PHB4 that belongs to a
+ * pec->stacks[stack_index] stack.
+ */
+int pnv_phb4_pec_get_phb_id(PnvPhb4PecState *pec, int stack_index)
+{
+    PnvPhb4PecClass *pecc = PNV_PHB4_PEC_GET_CLASS(pec);
+    int index = pec->index;
+    int offset = 0;
+
+    while (index--) {
+        offset += pecc->num_stacks[index];
+    }
+
+    return offset + stack_index;
+}
+
 /*
  * MSI/MSIX memory region implementation.
  * The handler handles both MSI and MSIX.
diff --git a/hw/pci-host/pnv_phb4_pec.c b/hw/pci-host/pnv_phb4_pec.c
index f3e4fa0c82..49360de8c8 100644
--- a/hw/pci-host/pnv_phb4_pec.c
+++ b/hw/pci-host/pnv_phb4_pec.c
@@ -374,19 +374,6 @@ static void pnv_pec_instance_init(Object *obj)
     }
 }
 
-static int pnv_pec_phb_offset(PnvPhb4PecState *pec)
-{
-    PnvPhb4PecClass *pecc = PNV_PHB4_PEC_GET_CLASS(pec);
-    int index = pec->index;
-    int offset = 0;
-
-    while (index--) {
-        offset += pecc->num_stacks[index];
-    }
-
-    return offset;
-}
-
 static void pnv_pec_realize(DeviceState *dev, Error **errp)
 {
     PnvPhb4PecState *pec = PNV_PHB4_PEC(dev);
@@ -405,7 +392,7 @@ static void pnv_pec_realize(DeviceState *dev, Error **errp)
     for (i = 0; i < pec->num_stacks; i++) {
         PnvPhb4PecStack *stack = &pec->stacks[i];
         Object *stk_obj = OBJECT(stack);
-        int phb_id = pnv_pec_phb_offset(pec) + i;
+        int phb_id = pnv_phb4_pec_get_phb_id(pec, i);
 
         object_property_set_int(stk_obj, "stack-no", i, &error_abort);
         object_property_set_int(stk_obj, "phb-id", phb_id, &error_abort);
diff --git a/include/hw/pci-host/pnv_phb4.h b/include/hw/pci-host/pnv_phb4.h
index 88dc6abb1c..5ee996ebc6 100644
--- a/include/hw/pci-host/pnv_phb4.h
+++ b/include/hw/pci-host/pnv_phb4.h
@@ -15,6 +15,7 @@
 #include "hw/ppc/xive.h"
 #include "qom/object.h"
 
+typedef struct PnvPhb4PecState PnvPhb4PecState;
 typedef struct PnvPhb4PecStack PnvPhb4PecStack;
 typedef struct PnvPHB4 PnvPHB4;
 typedef struct PnvChip PnvChip;
@@ -131,6 +132,7 @@ struct PnvPHB4 {
 
 void pnv_phb4_pic_print_info(PnvPHB4 *phb, Monitor *mon);
 void pnv_phb4_update_regions(PnvPhb4PecStack *stack);
+int pnv_phb4_pec_get_phb_id(PnvPhb4PecState *pec, int stack_index);
 extern const MemoryRegionOps pnv_phb4_xscom_ops;
 
 /*