+
+void sysbus_add_memory(SysBusDevice *dev, hwaddr addr,
+ MemoryRegion *mem)
+{
+ memory_region_add_subregion(get_system_memory(), addr, mem);
+}
+
+void sysbus_add_memory_overlap(SysBusDevice *dev, hwaddr addr,
+ MemoryRegion *mem, unsigned priority)
+{
+ memory_region_add_subregion_overlap(get_system_memory(), addr, mem,
+ priority);
+}
+
+void sysbus_del_memory(SysBusDevice *dev, MemoryRegion *mem)
+{
+ memory_region_del_subregion(get_system_memory(), mem);
+}
+
+void sysbus_add_io(SysBusDevice *dev, hwaddr addr,
+ MemoryRegion *mem)
+{
+ memory_region_add_subregion(get_system_io(), addr, mem);
+}
+
+void sysbus_del_io(SysBusDevice *dev, MemoryRegion *mem)
+{
+ memory_region_del_subregion(get_system_io(), mem);
+}
+
+MemoryRegion *sysbus_address_space(SysBusDevice *dev)
+{
+ return get_system_memory();
+}
+
+static void sysbus_device_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *k = DEVICE_CLASS(klass);
+ k->init = sysbus_device_init;
+ k->bus_type = TYPE_SYSTEM_BUS;
+}
+
+static const TypeInfo sysbus_device_type_info = {
+ .name = TYPE_SYS_BUS_DEVICE,
+ .parent = TYPE_DEVICE,
+ .instance_size = sizeof(SysBusDevice),
+ .abstract = true,
+ .class_size = sizeof(SysBusDeviceClass),
+ .class_init = sysbus_device_class_init,
+};
+
+/* This is a nasty hack to allow passing a NULL bus to qdev_create. */
+static BusState *main_system_bus;
+
+static void main_system_bus_create(void)
+{
+ /* assign main_system_bus before qbus_create_inplace()
+ * in order to make "if (bus != sysbus_get_default())" work */
+ main_system_bus = g_malloc0(system_bus_info.instance_size);
+ qbus_create_inplace(main_system_bus, TYPE_SYSTEM_BUS, NULL,
+ "main-system-bus");
+ OBJECT(main_system_bus)->free = g_free;
+ object_property_add_child(container_get(qdev_get_machine(),
+ "/unattached"),
+ "sysbus", OBJECT(main_system_bus), NULL);
+}
+
+BusState *sysbus_get_default(void)
+{
+ if (!main_system_bus) {
+ main_system_bus_create();
+ }
+ return main_system_bus;
+}
+
+static void sysbus_register_types(void)
+{
+ type_register_static(&system_bus_info);
+ type_register_static(&sysbus_device_type_info);
+}
+
+type_init(sysbus_register_types)