Enable ACPI table creation for PCI Expander Bridges to be independent
of PCI internals.  Note that the UID is currently the PCI bus number.
This is motivated by the forthcoming ACPI Generic Port SRAT entries
which can be made completely independent of PCI internals.

Suggested-by: Igor Mammedov <imammedo@redhat.com>
Tested-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 hw/pci-bridge/pci_expander_bridge.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/hw/pci-bridge/pci_expander_bridge.c b/hw/pci-bridge/pci_expander_bridge.c
index dfaea6cbf4..3d52ea5867 100644
--- a/hw/pci-bridge/pci_expander_bridge.c
+++ b/hw/pci-bridge/pci_expander_bridge.c
@@ -85,12 +85,25 @@ static uint16_t pxb_bus_numa_node(PCIBus *bus)
     return pxb->numa_node;
 }
 
+static void prop_pxb_uid_get(Object *obj, Visitor *v, const char *name,
+                             void *opaque, Error **errp)
+{
+    uint32_t uid = pci_bus_num(PCI_BUS(obj));
+
+    visit_type_uint32(v, name, &uid, errp);
+}
+
 static void pxb_bus_class_init(ObjectClass *class, void *data)
 {
     PCIBusClass *pbc = PCI_BUS_CLASS(class);
 
     pbc->bus_num = pxb_bus_num;
     pbc->numa_node = pxb_bus_numa_node;
+
+    object_class_property_add(class, "acpi_uid", "uint32",
+                              prop_pxb_uid_get, NULL, NULL, NULL);
+    object_class_property_set_description(class, "acpi_uid",
+        "ACPI Unique ID used to distinguish this PCI Host Bridge / ACPI00016");
 }
 
 static const TypeInfo pxb_bus_info = {
-- 
2.43.0