Linux boot API and usage in ARM boots

index 807978e..be7280c 100644
@@ -1494,6 +1494,21 @@ int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
                          void *opaque);
 
 /**
+ * object_child_foreach_recursive:
+ * @obj: the object whose children will be navigated
+ * @fn: the iterator function to be called
+ * @opaque: an opaque value that will be passed to the iterator
+ *
+ * Call @fn passing each child of @obj and @opaque to it, until @fn returns
+ * non-zero. Calls recursively, all child nodes of @obj will also be passed
+ * all the way down to the leaf nodes of the tree. Depth first ordering.
+ *
+ * Returns: The last value returned by @fn, or 0 if there is no child.
+ */
+int object_child_foreach_recursive(Object *obj,
+                                   int (*fn)(Object *child, void *opaque),
+                                   void *opaque);
+/**
  * container_get:
  * @root: root of the #path, e.g., object_get_root()
  * @path: path to the container

index ee38431..081da83 100644
@@ -775,23 +775,42 @@ void object_class_foreach(void (*fn)(ObjectClass *klass, void *opaque),
     enumerating_types = false;
 }
 
-int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
-                         void *opaque)
+static int do_object_child_foreach(Object *obj,
+                                   int (*fn)(Object *child, void *opaque),
+                                   void *opaque, bool recurse)
 {
     ObjectProperty *prop, *next;
     int ret = 0;
 
     QTAILQ_FOREACH_SAFE(prop, &obj->properties, node, next) {
         if (object_property_is_child(prop)) {
-            ret = fn(prop->opaque, opaque);
+            Object *child = prop->opaque;
+
+            ret = fn(child, opaque);
             if (ret != 0) {
                 break;
             }
+            if (recurse) {
+                do_object_child_foreach(child, fn, opaque, true);
+            }
         }
     }
     return ret;
 }
 
+int object_child_foreach(Object *obj, int (*fn)(Object *child, void *opaque),
+                         void *opaque)
+{
+    return do_object_child_foreach(obj, fn, opaque, false);
+}
+
+int object_child_foreach_recursive(Object *obj,
+                                   int (*fn)(Object *child, void *opaque),
+                                   void *opaque)
+{
+    return do_object_child_foreach(obj, fn, opaque, true);
+}
+
 static void object_class_get_list_tramp(ObjectClass *klass, void *opaque)
 {
     GSList **list = opaque;

new file mode 100644
index 0000000..70d9652
@@ -0,0 +1,14 @@
+#include "hw/guest/linux.h"
+
+static const TypeInfo linux_device_info = {
+    .name          = TYPE_LINUX_DEVICE,
+    .parent        = TYPE_INTERFACE,
+    .class_size = sizeof(LinuxDeviceClass),
+};
+
+static void linux_register_types(void)
+{
+    type_register_static(&linux_device_info);
+}
+
+type_init(linux_register_types)

new file mode 100644
index 0000000..b481a33
@@ -0,0 +1,32 @@
+#ifndef GUEST_LINUX_H
+
+#include "qemu-common.h"
+#include "qom/object.h"
+
+#define TYPE_LINUX_DEVICE "linux,device"
+
+#define LINUX_DEVICE_CLASS(klass) \
+    OBJECT_CLASS_CHECK(LinuxDeviceClass, (klass), TYPE_LINUX_DEVICE)
+#define LINUX_DEVICE_GET_CLASS(obj) \
+    OBJECT_GET_CLASS(LinuxDeviceClass, (obj), TYPE_LINUX_DEVICE)
+#define LINUX_DEVICE(obj) \
+    INTERFACE_CHECK(LinuxDevice, (obj), TYPE_LINUX_DEVICE)
+
+typedef struct LinuxDevice {
+    /*< private >*/
+    Object parent_obj;
+} LinuxDevice;
+
+typedef struct LinuxDeviceClass {
+    /*< private > */
+    InterfaceClass parent_class;
+
+    /*< public >*/
+    /** linux_init - Init the device for a Linux boot. Setup the device in the
+     * correct post-firmware state for a Linux boot.
+     */
+    void (*linux_init)(LinuxDevice *obj);
+} LinuxDeviceClass;
+
+#define GUEST_LINUX_H
+#endif

index 454bfd7..9374145 100644
@@ -22,6 +22,8 @@
 #include "gic_internal.h"
 #include "qom/cpu.h"
 
+#include "hw/guest/linux.h"
+
 //#define DEBUG_GIC
 
 #ifdef DEBUG_GIC

@@ -1135,13 +1137,28 @@ static void arm_gic_realize(DeviceState *dev, Error **errp)
     }
 }
 
+static void arm_gic_linux_init(LinuxDevice *obj)
+{
+    /* FIXME: rebase - this is based on Xilinx tree code */
+#if 0
+    GICState *s = ARM_GIC(obj);
+    int i;
+
+    for (i = 0 ; i < s->num_irq; ++i) {
+        s->irq_state[i].group = 1;
+    }
+#endif
+}
+
 static void arm_gic_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
     ARMGICClass *agc = ARM_GIC_CLASS(klass);
+    LinuxDeviceClass *ldc = LINUX_DEVICE_CLASS(klass);
 
     agc->parent_realize = dc->realize;
     dc->realize = arm_gic_realize;
+    ldc->linux_init = arm_gic_linux_init;
 }
 
 static const TypeInfo arm_gic_info = {

@@ -1150,6 +1167,10 @@ static const TypeInfo arm_gic_info = {
     .instance_size = sizeof(GICState),
     .class_init = arm_gic_class_init,
     .class_size = sizeof(ARMGICClass),
+    .interfaces = (InterfaceInfo []) {
+        { TYPE_LINUX_DEVICE },
+        { },
+    }
 };
 
 static void arm_gic_register_types(void)

index 1e7fd28..2cf0dcb 100644
@@ -18,6 +18,8 @@
 #include "qemu/config-file.h"
 #include "exec/address-spaces.h"
 
+#include "hw/guest/linux.h"
+
 /* Kernel boot protocol is specified in the kernel docs
  * Documentation/arm/Booting and Documentation/arm64/booting.txt
  * They have different preferred image load offsets from system RAM base.

@@ -442,6 +444,19 @@ fail:
     return -1;
 }
 
+static int do_linux_dev_init(Object *obj, void *opaue)
+{
+    if (object_dynamic_cast(obj, TYPE_LINUX_DEVICE)) {
+        LinuxDevice *ld = LINUX_DEVICE(obj);
+        LinuxDeviceClass *ldc = LINUX_DEVICE_GET_CLASS(obj);
+
+        if (ldc->linux_init) {
+            ldc->linux_init(ld);
+        }
+    }
+    return 0;
+}
+
 static void do_cpu_reset(void *opaque)
 {
     ARMCPU *cpu = opaque;

@@ -504,8 +519,11 @@ static void do_cpu_reset(void *opaque)
             } else {
                 info->secondary_cpu_reset_hook(cpu, info);
             }
+            object_child_foreach_recursive(object_get_root(),
+                                           do_linux_dev_init, NULL);
         }
     }
+
 }
 
 /**