hw/i386: extend pxb query for all PC machines

Add bus property to PC machines and use it when looking
for primary PCI root bus (bus 0).
Signed-off-by: NMarcel Apfelbaum <marcel@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NEduardo Habkost <ehabkost@redhat.com>

hw/i386/acpi-build.c

@@ -950,8 +950,7 @@ build_ssdt(GArray *table_data, GArray *linker,
     /* Reserve space for header */
     acpi_data_push(ssdt->buf, sizeof(AcpiTableHeader));
 
-    /* Extra PCI root buses are implemented  only for i440fx */
-    bus = find_i440fx();
+    bus = PC_MACHINE(machine)->bus;
     if (bus) {
         QLIST_FOREACH(bus, &bus->child, sibling) {
             uint8_t bus_num = pci_bus_num(bus);

hw/i386/pc.c

@@ -1167,7 +1167,7 @@ void pc_guest_info_machine_done(Notifier *notifier, void *data)
     PcGuestInfoState *guest_info_state = container_of(notifier,
                                                       PcGuestInfoState,
                                                       machine_done);
-    PCIBus *bus = find_i440fx();
+    PCIBus *bus = PC_MACHINE(qdev_get_machine())->bus;
 
     if (bus) {
         int extra_hosts = 0;

hw/i386/pc_piix.c

@@ -185,6 +185,7 @@ static void pc_init1(MachineState *machine,
                               pcms->below_4g_mem_size,
                               pcms->above_4g_mem_size,
                               pci_memory, ram_memory);
+        pcms->bus = pci_bus;
     } else {
         pci_bus = NULL;
         i440fx_state = NULL;

hw/i386/pc_q35.c

@@ -181,6 +181,7 @@ static void pc_q35_init(MachineState *machine)
     qdev_init_nofail(DEVICE(q35_host));
     phb = PCI_HOST_BRIDGE(q35_host);
     host_bus = phb->bus;
+    pcms->bus = phb->bus;
     /* create ISA bus */
     lpc = pci_create_simple_multifunction(host_bus, PCI_DEVFN(ICH9_LPC_DEV,
                                           ICH9_LPC_FUNC), true,

include/hw/i386/pc.h

@@ -51,6 +51,7 @@ struct PCMachineState {
     OnOffAuto vmport;
     OnOffAuto smm;
     ram_addr_t below_4g_mem_size, above_4g_mem_size;
+    PCIBus *bus;
 };
 
 #define PC_MACHINE_ACPI_DEVICE_PROP "acpi-device"