int i;
 
     /* Initialize SoC */
-    object_initialize(&s->soc, sizeof(s->soc), TYPE_RISCV_U_SOC);
-    object_property_add_child(OBJECT(machine), "soc", OBJECT(&s->soc),
-                              &error_abort);
+    object_initialize_child(OBJECT(machine), "soc", &s->soc,
+                            sizeof(s->soc), TYPE_RISCV_U_SOC,
+                            &error_abort, NULL);
     object_property_set_bool(OBJECT(&s->soc), true, "realized",
                             &error_abort);
 
 {
     SiFiveUSoCState *s = RISCV_U_SOC(obj);
 
-    object_initialize(&s->cpus, sizeof(s->cpus), TYPE_RISCV_HART_ARRAY);
-    object_property_add_child(obj, "cpus", OBJECT(&s->cpus),
-                              &error_abort);
+    object_initialize_child(obj, "cpus", &s->cpus, sizeof(s->cpus),
+                            TYPE_RISCV_HART_ARRAY, &error_abort, NULL);
     object_property_set_str(OBJECT(&s->cpus), SIFIVE_U_CPU, "cpu-type",
                             &error_abort);
     object_property_set_int(OBJECT(&s->cpus), smp_cpus, "num-harts",
                             &error_abort);
 
-    object_initialize(&s->gem, sizeof(s->gem), TYPE_CADENCE_GEM);
-    qdev_set_parent_bus(DEVICE(&s->gem), sysbus_get_default());
+    sysbus_init_child_obj(obj, "gem", &s->gem, sizeof(s->gem),
+                          TYPE_CADENCE_GEM);
 }
 
 static void riscv_sifive_u_soc_realize(DeviceState *dev, Error **errp)