hw/pci-host/gpex-acpi: Use acpi_uid property.

Reduce the direct use of PCI internals inside ACPI table creation.

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>
Message-Id: <20240916171017.1841767-10-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/pci-host/gpex-acpi.c

@@ -141,6 +141,7 @@ void acpi_dsdt_add_gpex(Aml *scope, struct GPEXConfig *cfg)
         QLIST_FOREACH(bus, &bus->child, sibling) {
             uint8_t bus_num = pci_bus_num(bus);
             uint8_t numa_node = pci_bus_numa_node(bus);
+            uint32_t uid;
             bool is_cxl = pci_bus_is_cxl(bus);
 
             if (!pci_bus_is_root(bus)) {
@@ -156,6 +157,8 @@ void acpi_dsdt_add_gpex(Aml *scope, struct GPEXConfig *cfg)
                 nr_pcie_buses = bus_num;
             }
 
+            uid = object_property_get_uint(OBJECT(bus), "acpi_uid",
+                                           &error_fatal);
             dev = aml_device("PC%.02X", bus_num);
             if (is_cxl) {
                 struct Aml *pkg = aml_package(2);
@@ -168,7 +171,7 @@ void acpi_dsdt_add_gpex(Aml *scope, struct GPEXConfig *cfg)
                 aml_append(dev, aml_name_decl("_CID", aml_string("PNP0A03")));
             }
             aml_append(dev, aml_name_decl("_BBN", aml_int(bus_num)));
-            aml_append(dev, aml_name_decl("_UID", aml_int(bus_num)));
+            aml_append(dev, aml_name_decl("_UID", aml_int(uid)));
             aml_append(dev, aml_name_decl("_STR", aml_unicode("pxb Device")));
             aml_append(dev, aml_name_decl("_CCA", aml_int(1)));
             if (numa_node != NUMA_NODE_UNASSIGNED) {