diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 7c5f2e283dbb43fe3a6d2221b9c516652f6764a9..7f28101cb488b942fc7b8aa8b2418c4763e637c1 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -297,6 +297,11 @@ static void pci_bus_init(PCIBus *bus, DeviceState *parent,
     vmstate_register(NULL, -1, &vmstate_pcibus, bus);
 }
 
+bool pci_bus_is_express(PCIBus *bus)
+{
+    return object_dynamic_cast(OBJECT(bus), TYPE_PCIE_BUS);
+}
+
 void pci_bus_new_inplace(PCIBus *bus, DeviceState *parent,
                          const char *name,
                          MemoryRegion *address_space_mem,
diff --git a/hw/pci/pci.h b/hw/pci/pci.h
index 10aeaf0cc6656d74434e5cd112c2d05ac2fd49f5..d715e6f09d24e1bf1f4c39467043da60f33eb9e3 100644
--- a/hw/pci/pci.h
+++ b/hw/pci/pci.h
@@ -344,6 +344,7 @@ typedef int (*pci_hotplug_fn)(DeviceState *qdev, PCIDevice *pci_dev,
 #define PCI_BUS(obj) OBJECT_CHECK(PCIBus, (obj), TYPE_PCI_BUS)
 #define TYPE_PCIE_BUS "PCIE"
 
+bool pci_bus_is_express(PCIBus *bus);
 void pci_bus_new_inplace(PCIBus *bus, DeviceState *parent,
                          const char *name,
                          MemoryRegion *address_space_mem,