QDev(qtree)

• previously separate API
• Now built on QOM
• Generic Device base class, can connect to buses
• Extra constructors realize()/unrealize() :(

Device Init

It show the class relationship.

/* hw/core/qdev.c: 652 */ 
static void device_initfn(Object *obj) { 
	DeviceState *dev = DEVICE(obj);  // translate Object to DeviceState (cast)
	if (phase_check(PHASE_MACHINE_READY)) {  // check machine init state
		dev->hotplugged = 1; 
		qdev_hot_added = true; 
	} 
	dev->instance_id_alias = -1;  // init device property
	dev->realized = false; // realized is false indicate device is not inited
	dev->allow_unplug_during_migration = false; 
	
	QLIST_INIT(&dev->gpios);  // init gpio and clocks
	QLIST_INIT(&dev->clocks); 
}

realized property set

In qdev_realize function, the realized property is set to true, the device complete the initial.