xref: /openbmc/qemu/include/hw/qdev-core.h (revision ed3a06b1)
1 #ifndef QDEV_CORE_H
2 #define QDEV_CORE_H
3 
4 #include "qemu/queue.h"
5 #include "qemu/bitmap.h"
6 #include "qemu/rcu.h"
7 #include "qemu/rcu_queue.h"
8 #include "qom/object.h"
9 #include "hw/hotplug.h"
10 #include "hw/resettable.h"
11 
12 enum {
13     DEV_NVECTORS_UNSPECIFIED = -1,
14 };
15 
16 #define TYPE_DEVICE "device"
17 OBJECT_DECLARE_TYPE(DeviceState, DeviceClass, DEVICE)
18 
19 typedef enum DeviceCategory {
20     DEVICE_CATEGORY_BRIDGE,
21     DEVICE_CATEGORY_USB,
22     DEVICE_CATEGORY_STORAGE,
23     DEVICE_CATEGORY_NETWORK,
24     DEVICE_CATEGORY_INPUT,
25     DEVICE_CATEGORY_DISPLAY,
26     DEVICE_CATEGORY_SOUND,
27     DEVICE_CATEGORY_MISC,
28     DEVICE_CATEGORY_CPU,
29     DEVICE_CATEGORY_WATCHDOG,
30     DEVICE_CATEGORY_MAX
31 } DeviceCategory;
32 
33 typedef void (*DeviceRealize)(DeviceState *dev, Error **errp);
34 typedef void (*DeviceUnrealize)(DeviceState *dev);
35 typedef void (*DeviceReset)(DeviceState *dev);
36 typedef void (*BusRealize)(BusState *bus, Error **errp);
37 typedef void (*BusUnrealize)(BusState *bus);
38 
39 /**
40  * DeviceClass:
41  * @props: Properties accessing state fields.
42  * @realize: Callback function invoked when the #DeviceState:realized
43  * property is changed to %true.
44  * @unrealize: Callback function invoked when the #DeviceState:realized
45  * property is changed to %false.
46  * @hotpluggable: indicates if #DeviceClass is hotpluggable, available
47  * as readonly "hotpluggable" property of #DeviceState instance
48  *
49  * # Realization #
50  * Devices are constructed in two stages,
51  * 1) object instantiation via object_initialize() and
52  * 2) device realization via #DeviceState:realized property.
53  * The former may not fail (and must not abort or exit, since it is called
54  * during device introspection already), and the latter may return error
55  * information to the caller and must be re-entrant.
56  * Trivial field initializations should go into #TypeInfo.instance_init.
57  * Operations depending on @props static properties should go into @realize.
58  * After successful realization, setting static properties will fail.
59  *
60  * As an interim step, the #DeviceState:realized property can also be
61  * set with qdev_realize().
62  * In the future, devices will propagate this state change to their children
63  * and along busses they expose.
64  * The point in time will be deferred to machine creation, so that values
65  * set in @realize will not be introspectable beforehand. Therefore devices
66  * must not create children during @realize; they should initialize them via
67  * object_initialize() in their own #TypeInfo.instance_init and forward the
68  * realization events appropriately.
69  *
70  * Any type may override the @realize and/or @unrealize callbacks but needs
71  * to call the parent type's implementation if keeping their functionality
72  * is desired. Refer to QOM documentation for further discussion and examples.
73  *
74  * <note>
75  *   <para>
76  * Since TYPE_DEVICE doesn't implement @realize and @unrealize, types
77  * derived directly from it need not call their parent's @realize and
78  * @unrealize.
79  * For other types consult the documentation and implementation of the
80  * respective parent types.
81  *   </para>
82  * </note>
83  *
84  * # Hiding a device #
85  * To hide a device, a DeviceListener function hide_device() needs to
86  * be registered.
87  * It can be used to defer adding a device and therefore hide it from
88  * the guest. The handler registering to this DeviceListener can save
89  * the QOpts passed to it for re-using it later. It must return if it
90  * wants the device to be hidden or visible. When the handler function
91  * decides the device shall be visible it will be added with
92  * qdev_device_add() and realized as any other device. Otherwise
93  * qdev_device_add() will return early without adding the device. The
94  * guest will not see a "hidden" device until it was marked visible
95  * and qdev_device_add called again.
96  *
97  */
98 struct DeviceClass {
99     /*< private >*/
100     ObjectClass parent_class;
101     /*< public >*/
102 
103     DECLARE_BITMAP(categories, DEVICE_CATEGORY_MAX);
104     const char *fw_name;
105     const char *desc;
106 
107     /*
108      * The underscore at the end ensures a compile-time error if someone
109      * assigns to dc->props instead of using device_class_set_props.
110      */
111     Property *props_;
112 
113     /*
114      * Can this device be instantiated with -device / device_add?
115      * All devices should support instantiation with device_add, and
116      * this flag should not exist.  But we're not there, yet.  Some
117      * devices fail to instantiate with cryptic error messages.
118      * Others instantiate, but don't work.  Exposing users to such
119      * behavior would be cruel; clearing this flag will protect them.
120      * It should never be cleared without a comment explaining why it
121      * is cleared.
122      * TODO remove once we're there
123      */
124     bool user_creatable;
125     bool hotpluggable;
126 
127     /* callbacks */
128     /*
129      * Reset method here is deprecated and replaced by methods in the
130      * resettable class interface to implement a multi-phase reset.
131      * TODO: remove once every reset callback is unused
132      */
133     DeviceReset reset;
134     DeviceRealize realize;
135     DeviceUnrealize unrealize;
136 
137     /* device state */
138     const VMStateDescription *vmsd;
139 
140     /* Private to qdev / bus.  */
141     const char *bus_type;
142 };
143 
144 typedef struct NamedGPIOList NamedGPIOList;
145 
146 struct NamedGPIOList {
147     char *name;
148     qemu_irq *in;
149     int num_in;
150     int num_out;
151     QLIST_ENTRY(NamedGPIOList) node;
152 };
153 
154 typedef struct Clock Clock;
155 typedef struct NamedClockList NamedClockList;
156 
157 struct NamedClockList {
158     char *name;
159     Clock *clock;
160     bool output;
161     bool alias;
162     QLIST_ENTRY(NamedClockList) node;
163 };
164 
165 /**
166  * DeviceState:
167  * @realized: Indicates whether the device has been fully constructed.
168  *            When accessed outside big qemu lock, must be accessed with
169  *            qatomic_load_acquire()
170  * @reset: ResettableState for the device; handled by Resettable interface.
171  *
172  * This structure should not be accessed directly.  We declare it here
173  * so that it can be embedded in individual device state structures.
174  */
175 struct DeviceState {
176     /*< private >*/
177     Object parent_obj;
178     /*< public >*/
179 
180     char *id;
181     char *canonical_path;
182     bool realized;
183     bool pending_deleted_event;
184     int64_t pending_deleted_expires_ms;
185     QDict *opts;
186     int hotplugged;
187     bool allow_unplug_during_migration;
188     BusState *parent_bus;
189     QLIST_HEAD(, NamedGPIOList) gpios;
190     QLIST_HEAD(, NamedClockList) clocks;
191     QLIST_HEAD(, BusState) child_bus;
192     int num_child_bus;
193     int instance_id_alias;
194     int alias_required_for_version;
195     ResettableState reset;
196     GSList *unplug_blockers;
197 };
198 
199 struct DeviceListener {
200     void (*realize)(DeviceListener *listener, DeviceState *dev);
201     void (*unrealize)(DeviceListener *listener, DeviceState *dev);
202     /*
203      * This callback is called upon init of the DeviceState and
204      * informs qdev if a device should be visible or hidden.  We can
205      * hide a failover device depending for example on the device
206      * opts.
207      *
208      * On errors, it returns false and errp is set. Device creation
209      * should fail in this case.
210      */
211     bool (*hide_device)(DeviceListener *listener, const QDict *device_opts,
212                         bool from_json, Error **errp);
213     QTAILQ_ENTRY(DeviceListener) link;
214 };
215 
216 #define TYPE_BUS "bus"
217 DECLARE_OBJ_CHECKERS(BusState, BusClass,
218                      BUS, TYPE_BUS)
219 
220 struct BusClass {
221     ObjectClass parent_class;
222 
223     /* FIXME first arg should be BusState */
224     void (*print_dev)(Monitor *mon, DeviceState *dev, int indent);
225     char *(*get_dev_path)(DeviceState *dev);
226 
227     /*
228      * This callback is used to create Open Firmware device path in accordance
229      * with OF spec http://forthworks.com/standards/of1275.pdf. Individual bus
230      * bindings can be found at http://playground.sun.com/1275/bindings/.
231      */
232     char *(*get_fw_dev_path)(DeviceState *dev);
233 
234     void (*reset)(BusState *bus);
235 
236     /*
237      * Return whether the device can be added to @bus,
238      * based on the address that was set (via device properties)
239      * before realize.  If not, on return @errp contains the
240      * human-readable error message.
241      */
242     bool (*check_address)(BusState *bus, DeviceState *dev, Error **errp);
243 
244     BusRealize realize;
245     BusUnrealize unrealize;
246 
247     /* maximum devices allowed on the bus, 0: no limit. */
248     int max_dev;
249     /* number of automatically allocated bus ids (e.g. ide.0) */
250     int automatic_ids;
251 };
252 
253 typedef struct BusChild {
254     struct rcu_head rcu;
255     DeviceState *child;
256     int index;
257     QTAILQ_ENTRY(BusChild) sibling;
258 } BusChild;
259 
260 #define QDEV_HOTPLUG_HANDLER_PROPERTY "hotplug-handler"
261 
262 /**
263  * BusState:
264  * @hotplug_handler: link to a hotplug handler associated with bus.
265  * @reset: ResettableState for the bus; handled by Resettable interface.
266  */
267 struct BusState {
268     Object obj;
269     DeviceState *parent;
270     char *name;
271     HotplugHandler *hotplug_handler;
272     int max_index;
273     bool realized;
274     bool full;
275     int num_children;
276 
277     /*
278      * children is a RCU QTAILQ, thus readers must use RCU to access it,
279      * and writers must hold the big qemu lock
280      */
281 
282     QTAILQ_HEAD(, BusChild) children;
283     QLIST_ENTRY(BusState) sibling;
284     ResettableState reset;
285 };
286 
287 /**
288  * GlobalProperty:
289  * @used: Set to true if property was used when initializing a device.
290  * @optional: If set to true, GlobalProperty will be skipped without errors
291  *            if the property doesn't exist.
292  *
293  * An error is fatal for non-hotplugged devices, when the global is applied.
294  */
295 typedef struct GlobalProperty {
296     const char *driver;
297     const char *property;
298     const char *value;
299     bool used;
300     bool optional;
301 } GlobalProperty;
302 
303 static inline void
304 compat_props_add(GPtrArray *arr,
305                  GlobalProperty props[], size_t nelem)
306 {
307     int i;
308     for (i = 0; i < nelem; i++) {
309         g_ptr_array_add(arr, (void *)&props[i]);
310     }
311 }
312 
313 /*** Board API.  This should go away once we have a machine config file.  ***/
314 
315 /**
316  * qdev_new: Create a device on the heap
317  * @name: device type to create (we assert() that this type exists)
318  *
319  * This only allocates the memory and initializes the device state
320  * structure, ready for the caller to set properties if they wish.
321  * The device still needs to be realized.
322  * The returned object has a reference count of 1.
323  */
324 DeviceState *qdev_new(const char *name);
325 
326 /**
327  * qdev_try_new: Try to create a device on the heap
328  * @name: device type to create
329  *
330  * This is like qdev_new(), except it returns %NULL when type @name
331  * does not exist, rather than asserting.
332  */
333 DeviceState *qdev_try_new(const char *name);
334 
335 /**
336  * qdev_realize: Realize @dev.
337  * @dev: device to realize
338  * @bus: bus to plug it into (may be NULL)
339  * @errp: pointer to error object
340  *
341  * "Realize" the device, i.e. perform the second phase of device
342  * initialization.
343  * @dev must not be plugged into a bus already.
344  * If @bus, plug @dev into @bus.  This takes a reference to @dev.
345  * If @dev has no QOM parent, make one up, taking another reference.
346  * On success, return true.
347  * On failure, store an error through @errp and return false.
348  *
349  * If you created @dev using qdev_new(), you probably want to use
350  * qdev_realize_and_unref() instead.
351  */
352 bool qdev_realize(DeviceState *dev, BusState *bus, Error **errp);
353 
354 /**
355  * qdev_realize_and_unref: Realize @dev and drop a reference
356  * @dev: device to realize
357  * @bus: bus to plug it into (may be NULL)
358  * @errp: pointer to error object
359  *
360  * Realize @dev and drop a reference.
361  * This is like qdev_realize(), except the caller must hold a
362  * (private) reference, which is dropped on return regardless of
363  * success or failure.  Intended use::
364  *
365  *     dev = qdev_new();
366  *     [...]
367  *     qdev_realize_and_unref(dev, bus, errp);
368  *
369  * Now @dev can go away without further ado.
370  *
371  * If you are embedding the device into some other QOM device and
372  * initialized it via some variant on object_initialize_child() then
373  * do not use this function, because that family of functions arrange
374  * for the only reference to the child device to be held by the parent
375  * via the child<> property, and so the reference-count-drop done here
376  * would be incorrect. For that use case you want qdev_realize().
377  */
378 bool qdev_realize_and_unref(DeviceState *dev, BusState *bus, Error **errp);
379 
380 /**
381  * qdev_unrealize: Unrealize a device
382  * @dev: device to unrealize
383  *
384  * This function will "unrealize" a device, which is the first phase
385  * of correctly destroying a device that has been realized. It will:
386  *
387  *  - unrealize any child buses by calling qbus_unrealize()
388  *    (this will recursively unrealize any devices on those buses)
389  *  - call the the unrealize method of @dev
390  *
391  * The device can then be freed by causing its reference count to go
392  * to zero.
393  *
394  * Warning: most devices in QEMU do not expect to be unrealized.  Only
395  * devices which are hot-unpluggable should be unrealized (as part of
396  * the unplugging process); all other devices are expected to last for
397  * the life of the simulation and should not be unrealized and freed.
398  */
399 void qdev_unrealize(DeviceState *dev);
400 void qdev_set_legacy_instance_id(DeviceState *dev, int alias_id,
401                                  int required_for_version);
402 HotplugHandler *qdev_get_bus_hotplug_handler(DeviceState *dev);
403 HotplugHandler *qdev_get_machine_hotplug_handler(DeviceState *dev);
404 bool qdev_hotplug_allowed(DeviceState *dev, Error **errp);
405 /**
406  * qdev_get_hotplug_handler: Get handler responsible for device wiring
407  *
408  * Find HOTPLUG_HANDLER for @dev that provides [pre|un]plug callbacks for it.
409  *
410  * Note: in case @dev has a parent bus, it will be returned as handler unless
411  * machine handler overrides it.
412  *
413  * Returns: pointer to object that implements TYPE_HOTPLUG_HANDLER interface
414  *          or NULL if there aren't any.
415  */
416 HotplugHandler *qdev_get_hotplug_handler(DeviceState *dev);
417 void qdev_unplug(DeviceState *dev, Error **errp);
418 void qdev_simple_device_unplug_cb(HotplugHandler *hotplug_dev,
419                                   DeviceState *dev, Error **errp);
420 void qdev_machine_creation_done(void);
421 bool qdev_machine_modified(void);
422 
423 /**
424  * qdev_add_unplug_blocker: Add an unplug blocker to a device
425  *
426  * @dev: Device to be blocked from unplug
427  * @reason: Reason for blocking
428  */
429 void qdev_add_unplug_blocker(DeviceState *dev, Error *reason);
430 
431 /**
432  * qdev_del_unplug_blocker: Remove an unplug blocker from a device
433  *
434  * @dev: Device to be unblocked
435  * @reason: Pointer to the Error used with qdev_add_unplug_blocker.
436  *          Used as a handle to lookup the blocker for deletion.
437  */
438 void qdev_del_unplug_blocker(DeviceState *dev, Error *reason);
439 
440 /**
441  * qdev_unplug_blocked: Confirm if a device is blocked from unplug
442  *
443  * @dev: Device to be tested
444  * @reason: Returns one of the reasons why the device is blocked,
445  *          if any
446  *
447  * Returns: true if device is blocked from unplug, false otherwise
448  */
449 bool qdev_unplug_blocked(DeviceState *dev, Error **errp);
450 
451 /**
452  * GpioPolarity: Polarity of a GPIO line
453  *
454  * GPIO lines use either positive (active-high) logic,
455  * or negative (active-low) logic.
456  *
457  * In active-high logic (%GPIO_POLARITY_ACTIVE_HIGH), a pin is
458  * active when the voltage on the pin is high (relative to ground);
459  * whereas in active-low logic (%GPIO_POLARITY_ACTIVE_LOW), a pin
460  * is active when the voltage on the pin is low (or grounded).
461  */
462 typedef enum {
463     GPIO_POLARITY_ACTIVE_LOW,
464     GPIO_POLARITY_ACTIVE_HIGH
465 } GpioPolarity;
466 
467 /**
468  * qdev_get_gpio_in: Get one of a device's anonymous input GPIO lines
469  * @dev: Device whose GPIO we want
470  * @n: Number of the anonymous GPIO line (which must be in range)
471  *
472  * Returns the qemu_irq corresponding to an anonymous input GPIO line
473  * (which the device has set up with qdev_init_gpio_in()). The index
474  * @n of the GPIO line must be valid (i.e. be at least 0 and less than
475  * the total number of anonymous input GPIOs the device has); this
476  * function will assert() if passed an invalid index.
477  *
478  * This function is intended to be used by board code or SoC "container"
479  * device models to wire up the GPIO lines; usually the return value
480  * will be passed to qdev_connect_gpio_out() or a similar function to
481  * connect another device's output GPIO line to this input.
482  *
483  * For named input GPIO lines, use qdev_get_gpio_in_named().
484  */
485 qemu_irq qdev_get_gpio_in(DeviceState *dev, int n);
486 
487 /**
488  * qdev_get_gpio_in_named: Get one of a device's named input GPIO lines
489  * @dev: Device whose GPIO we want
490  * @name: Name of the input GPIO array
491  * @n: Number of the GPIO line in that array (which must be in range)
492  *
493  * Returns the qemu_irq corresponding to a named input GPIO line
494  * (which the device has set up with qdev_init_gpio_in_named()).
495  * The @name string must correspond to an input GPIO array which exists on
496  * the device, and the index @n of the GPIO line must be valid (i.e.
497  * be at least 0 and less than the total number of input GPIOs in that
498  * array); this function will assert() if passed an invalid name or index.
499  *
500  * For anonymous input GPIO lines, use qdev_get_gpio_in().
501  */
502 qemu_irq qdev_get_gpio_in_named(DeviceState *dev, const char *name, int n);
503 
504 /**
505  * qdev_connect_gpio_out: Connect one of a device's anonymous output GPIO lines
506  * @dev: Device whose GPIO to connect
507  * @n: Number of the anonymous output GPIO line (which must be in range)
508  * @input_pin: qemu_irq to connect the output line to
509  *
510  * This function connects an anonymous output GPIO line on a device
511  * up to an arbitrary qemu_irq, so that when the device asserts that
512  * output GPIO line, the qemu_irq's callback is invoked.
513  * The index @n of the GPIO line must be valid (i.e. be at least 0 and
514  * less than the total number of anonymous output GPIOs the device has
515  * created with qdev_init_gpio_out()); otherwise this function will assert().
516  *
517  * Outbound GPIO lines can be connected to any qemu_irq, but the common
518  * case is connecting them to another device's inbound GPIO line, using
519  * the qemu_irq returned by qdev_get_gpio_in() or qdev_get_gpio_in_named().
520  *
521  * It is not valid to try to connect one outbound GPIO to multiple
522  * qemu_irqs at once, or to connect multiple outbound GPIOs to the
523  * same qemu_irq. (Warning: there is no assertion or other guard to
524  * catch this error: the model will just not do the right thing.)
525  * Instead, for fan-out you can use the TYPE_SPLIT_IRQ device: connect
526  * a device's outbound GPIO to the splitter's input, and connect each
527  * of the splitter's outputs to a different device.  For fan-in you
528  * can use the TYPE_OR_IRQ device, which is a model of a logical OR
529  * gate with multiple inputs and one output.
530  *
531  * For named output GPIO lines, use qdev_connect_gpio_out_named().
532  */
533 void qdev_connect_gpio_out(DeviceState *dev, int n, qemu_irq pin);
534 
535 /**
536  * qdev_connect_gpio_out_named: Connect one of a device's named output
537  *                              GPIO lines
538  * @dev: Device whose GPIO to connect
539  * @name: Name of the output GPIO array
540  * @n: Number of the anonymous output GPIO line (which must be in range)
541  * @input_pin: qemu_irq to connect the output line to
542  *
543  * This function connects an anonymous output GPIO line on a device
544  * up to an arbitrary qemu_irq, so that when the device asserts that
545  * output GPIO line, the qemu_irq's callback is invoked.
546  * The @name string must correspond to an output GPIO array which exists on
547  * the device, and the index @n of the GPIO line must be valid (i.e.
548  * be at least 0 and less than the total number of input GPIOs in that
549  * array); this function will assert() if passed an invalid name or index.
550  *
551  * Outbound GPIO lines can be connected to any qemu_irq, but the common
552  * case is connecting them to another device's inbound GPIO line, using
553  * the qemu_irq returned by qdev_get_gpio_in() or qdev_get_gpio_in_named().
554  *
555  * It is not valid to try to connect one outbound GPIO to multiple
556  * qemu_irqs at once, or to connect multiple outbound GPIOs to the
557  * same qemu_irq; see qdev_connect_gpio_out() for details.
558  *
559  * For anonymous output GPIO lines, use qdev_connect_gpio_out().
560  */
561 void qdev_connect_gpio_out_named(DeviceState *dev, const char *name, int n,
562                                  qemu_irq input_pin);
563 
564 /**
565  * qdev_get_gpio_out_connector: Get the qemu_irq connected to an output GPIO
566  * @dev: Device whose output GPIO we are interested in
567  * @name: Name of the output GPIO array
568  * @n: Number of the output GPIO line within that array
569  *
570  * Returns whatever qemu_irq is currently connected to the specified
571  * output GPIO line of @dev. This will be NULL if the output GPIO line
572  * has never been wired up to the anything.  Note that the qemu_irq
573  * returned does not belong to @dev -- it will be the input GPIO or
574  * IRQ of whichever device the board code has connected up to @dev's
575  * output GPIO.
576  *
577  * You probably don't need to use this function -- it is used only
578  * by the platform-bus subsystem.
579  */
580 qemu_irq qdev_get_gpio_out_connector(DeviceState *dev, const char *name, int n);
581 
582 /**
583  * qdev_intercept_gpio_out: Intercept an existing GPIO connection
584  * @dev: Device to intercept the outbound GPIO line from
585  * @icpt: New qemu_irq to connect instead
586  * @name: Name of the output GPIO array
587  * @n: Number of the GPIO line in the array
588  *
589  * This function is provided only for use by the qtest testing framework
590  * and is not suitable for use in non-testing parts of QEMU.
591  *
592  * This function breaks an existing connection of an outbound GPIO
593  * line from @dev, and replaces it with the new qemu_irq @icpt, as if
594  * ``qdev_connect_gpio_out_named(dev, icpt, name, n)`` had been called.
595  * The previously connected qemu_irq is returned, so it can be restored
596  * by a second call to qdev_intercept_gpio_out() if desired.
597  */
598 qemu_irq qdev_intercept_gpio_out(DeviceState *dev, qemu_irq icpt,
599                                  const char *name, int n);
600 
601 BusState *qdev_get_child_bus(DeviceState *dev, const char *name);
602 
603 /*** Device API.  ***/
604 
605 /**
606  * qdev_init_gpio_in: create an array of anonymous input GPIO lines
607  * @dev: Device to create input GPIOs for
608  * @handler: Function to call when GPIO line value is set
609  * @n: Number of GPIO lines to create
610  *
611  * Devices should use functions in the qdev_init_gpio_in* family in
612  * their instance_init or realize methods to create any input GPIO
613  * lines they need. There is no functional difference between
614  * anonymous and named GPIO lines. Stylistically, named GPIOs are
615  * preferable (easier to understand at callsites) unless a device
616  * has exactly one uniform kind of GPIO input whose purpose is obvious.
617  * Note that input GPIO lines can serve as 'sinks' for IRQ lines.
618  *
619  * See qdev_get_gpio_in() for how code that uses such a device can get
620  * hold of an input GPIO line to manipulate it.
621  */
622 void qdev_init_gpio_in(DeviceState *dev, qemu_irq_handler handler, int n);
623 
624 /**
625  * qdev_init_gpio_out: create an array of anonymous output GPIO lines
626  * @dev: Device to create output GPIOs for
627  * @pins: Pointer to qemu_irq or qemu_irq array for the GPIO lines
628  * @n: Number of GPIO lines to create
629  *
630  * Devices should use functions in the qdev_init_gpio_out* family
631  * in their instance_init or realize methods to create any output
632  * GPIO lines they need. There is no functional difference between
633  * anonymous and named GPIO lines. Stylistically, named GPIOs are
634  * preferable (easier to understand at callsites) unless a device
635  * has exactly one uniform kind of GPIO output whose purpose is obvious.
636  *
637  * The @pins argument should be a pointer to either a "qemu_irq"
638  * (if @n == 1) or a "qemu_irq []" array (if @n > 1) in the device's
639  * state structure. The device implementation can then raise and
640  * lower the GPIO line by calling qemu_set_irq(). (If anything is
641  * connected to the other end of the GPIO this will cause the handler
642  * function for that input GPIO to be called.)
643  *
644  * See qdev_connect_gpio_out() for how code that uses such a device
645  * can connect to one of its output GPIO lines.
646  *
647  * There is no need to release the @pins allocated array because it
648  * will be automatically released when @dev calls its instance_finalize()
649  * handler.
650  */
651 void qdev_init_gpio_out(DeviceState *dev, qemu_irq *pins, int n);
652 
653 /**
654  * qdev_init_gpio_out_named: create an array of named output GPIO lines
655  * @dev: Device to create output GPIOs for
656  * @pins: Pointer to qemu_irq or qemu_irq array for the GPIO lines
657  * @name: Name to give this array of GPIO lines
658  * @n: Number of GPIO lines to create
659  *
660  * Like qdev_init_gpio_out(), but creates an array of GPIO output lines
661  * with a name. Code using the device can then connect these GPIO lines
662  * using qdev_connect_gpio_out_named().
663  */
664 void qdev_init_gpio_out_named(DeviceState *dev, qemu_irq *pins,
665                               const char *name, int n);
666 
667 /**
668  * qdev_init_gpio_in_named_with_opaque: create an array of input GPIO lines
669  *   for the specified device
670  *
671  * @dev: Device to create input GPIOs for
672  * @handler: Function to call when GPIO line value is set
673  * @opaque: Opaque data pointer to pass to @handler
674  * @name: Name of the GPIO input (must be unique for this device)
675  * @n: Number of GPIO lines in this input set
676  */
677 void qdev_init_gpio_in_named_with_opaque(DeviceState *dev,
678                                          qemu_irq_handler handler,
679                                          void *opaque,
680                                          const char *name, int n);
681 
682 /**
683  * qdev_init_gpio_in_named: create an array of input GPIO lines
684  *   for the specified device
685  *
686  * Like qdev_init_gpio_in_named_with_opaque(), but the opaque pointer
687  * passed to the handler is @dev (which is the most commonly desired behaviour).
688  */
689 static inline void qdev_init_gpio_in_named(DeviceState *dev,
690                                            qemu_irq_handler handler,
691                                            const char *name, int n)
692 {
693     qdev_init_gpio_in_named_with_opaque(dev, handler, dev, name, n);
694 }
695 
696 /**
697  * qdev_pass_gpios: create GPIO lines on container which pass through to device
698  * @dev: Device which has GPIO lines
699  * @container: Container device which needs to expose them
700  * @name: Name of GPIO array to pass through (NULL for the anonymous GPIO array)
701  *
702  * In QEMU, complicated devices like SoCs are often modelled with a
703  * "container" QOM device which itself contains other QOM devices and
704  * which wires them up appropriately. This function allows the container
705  * to create GPIO arrays on itself which simply pass through to a GPIO
706  * array of one of its internal devices.
707  *
708  * If @dev has both input and output GPIOs named @name then both will
709  * be passed through. It is not possible to pass a subset of the array
710  * with this function.
711  *
712  * To users of the container device, the GPIO array created on @container
713  * behaves exactly like any other.
714  */
715 void qdev_pass_gpios(DeviceState *dev, DeviceState *container,
716                      const char *name);
717 
718 BusState *qdev_get_parent_bus(DeviceState *dev);
719 
720 /*** BUS API. ***/
721 
722 DeviceState *qdev_find_recursive(BusState *bus, const char *id);
723 
724 /* Returns 0 to walk children, > 0 to skip walk, < 0 to terminate walk. */
725 typedef int (qbus_walkerfn)(BusState *bus, void *opaque);
726 typedef int (qdev_walkerfn)(DeviceState *dev, void *opaque);
727 
728 void qbus_init(void *bus, size_t size, const char *typename,
729                DeviceState *parent, const char *name);
730 BusState *qbus_new(const char *typename, DeviceState *parent, const char *name);
731 bool qbus_realize(BusState *bus, Error **errp);
732 void qbus_unrealize(BusState *bus);
733 
734 /* Returns > 0 if either devfn or busfn skip walk somewhere in cursion,
735  *         < 0 if either devfn or busfn terminate walk somewhere in cursion,
736  *           0 otherwise. */
737 int qbus_walk_children(BusState *bus,
738                        qdev_walkerfn *pre_devfn, qbus_walkerfn *pre_busfn,
739                        qdev_walkerfn *post_devfn, qbus_walkerfn *post_busfn,
740                        void *opaque);
741 int qdev_walk_children(DeviceState *dev,
742                        qdev_walkerfn *pre_devfn, qbus_walkerfn *pre_busfn,
743                        qdev_walkerfn *post_devfn, qbus_walkerfn *post_busfn,
744                        void *opaque);
745 
746 /**
747  * @qdev_reset_all:
748  * Reset @dev. See @qbus_reset_all() for more details.
749  *
750  * Note: This function is deprecated and will be removed when it becomes unused.
751  * Please use device_cold_reset() now.
752  */
753 void qdev_reset_all(DeviceState *dev);
754 void qdev_reset_all_fn(void *opaque);
755 
756 /**
757  * @qbus_reset_all:
758  * @bus: Bus to be reset.
759  *
760  * Reset @bus and perform a bus-level ("hard") reset of all devices connected
761  * to it, including recursive processing of all buses below @bus itself.  A
762  * hard reset means that qbus_reset_all will reset all state of the device.
763  * For PCI devices, for example, this will include the base address registers
764  * or configuration space.
765  *
766  * Note: This function is deprecated and will be removed when it becomes unused.
767  * Please use bus_cold_reset() now.
768  */
769 void qbus_reset_all(BusState *bus);
770 void qbus_reset_all_fn(void *opaque);
771 
772 /**
773  * device_cold_reset:
774  * Reset device @dev and perform a recursive processing using the resettable
775  * interface. It triggers a RESET_TYPE_COLD.
776  */
777 void device_cold_reset(DeviceState *dev);
778 
779 /**
780  * bus_cold_reset:
781  *
782  * Reset bus @bus and perform a recursive processing using the resettable
783  * interface. It triggers a RESET_TYPE_COLD.
784  */
785 void bus_cold_reset(BusState *bus);
786 
787 /**
788  * device_is_in_reset:
789  * Return true if the device @dev is currently being reset.
790  */
791 bool device_is_in_reset(DeviceState *dev);
792 
793 /**
794  * bus_is_in_reset:
795  * Return true if the bus @bus is currently being reset.
796  */
797 bool bus_is_in_reset(BusState *bus);
798 
799 /* This should go away once we get rid of the NULL bus hack */
800 BusState *sysbus_get_default(void);
801 
802 char *qdev_get_fw_dev_path(DeviceState *dev);
803 char *qdev_get_own_fw_dev_path_from_handler(BusState *bus, DeviceState *dev);
804 
805 /**
806  * device_legacy_reset:
807  *
808  * Reset a single device (by calling the reset method).
809  * Note: This function is deprecated and will be removed when it becomes unused.
810  * Please use device_cold_reset() now.
811  */
812 void device_legacy_reset(DeviceState *dev);
813 
814 void device_class_set_props(DeviceClass *dc, Property *props);
815 
816 /**
817  * device_class_set_parent_reset:
818  * TODO: remove the function when DeviceClass's reset method
819  * is not used anymore.
820  */
821 void device_class_set_parent_reset(DeviceClass *dc,
822                                    DeviceReset dev_reset,
823                                    DeviceReset *parent_reset);
824 void device_class_set_parent_realize(DeviceClass *dc,
825                                      DeviceRealize dev_realize,
826                                      DeviceRealize *parent_realize);
827 void device_class_set_parent_unrealize(DeviceClass *dc,
828                                        DeviceUnrealize dev_unrealize,
829                                        DeviceUnrealize *parent_unrealize);
830 
831 const VMStateDescription *qdev_get_vmsd(DeviceState *dev);
832 
833 const char *qdev_fw_name(DeviceState *dev);
834 
835 void qdev_assert_realized_properly(void);
836 Object *qdev_get_machine(void);
837 
838 /* FIXME: make this a link<> */
839 bool qdev_set_parent_bus(DeviceState *dev, BusState *bus, Error **errp);
840 
841 extern bool qdev_hot_removed;
842 
843 char *qdev_get_dev_path(DeviceState *dev);
844 
845 void qbus_set_hotplug_handler(BusState *bus, Object *handler);
846 void qbus_set_bus_hotplug_handler(BusState *bus);
847 
848 static inline bool qbus_is_hotpluggable(BusState *bus)
849 {
850    return bus->hotplug_handler;
851 }
852 
853 /**
854  * qbus_mark_full: Mark this bus as full, so no more devices can be attached
855  * @bus: Bus to mark as full
856  *
857  * By default, QEMU will allow devices to be plugged into a bus up
858  * to the bus class's device count limit. Calling this function
859  * marks a particular bus as full, so that no more devices can be
860  * plugged into it. In particular this means that the bus will not
861  * be considered as a candidate for plugging in devices created by
862  * the user on the commandline or via the monitor.
863  * If a machine has multiple buses of a given type, such as I2C,
864  * where some of those buses in the real hardware are used only for
865  * internal devices and some are exposed via expansion ports, you
866  * can use this function to mark the internal-only buses as full
867  * after you have created all their internal devices. Then user
868  * created devices will appear on the expansion-port bus where
869  * guest software expects them.
870  */
871 static inline void qbus_mark_full(BusState *bus)
872 {
873     bus->full = true;
874 }
875 
876 void device_listener_register(DeviceListener *listener);
877 void device_listener_unregister(DeviceListener *listener);
878 
879 /**
880  * @qdev_should_hide_device:
881  * @opts: options QDict
882  * @from_json: true if @opts entries are typed, false for all strings
883  * @errp: pointer to error object
884  *
885  * Check if a device should be added.
886  * When a device is added via qdev_device_add() this will be called,
887  * and return if the device should be added now or not.
888  */
889 bool qdev_should_hide_device(const QDict *opts, bool from_json, Error **errp);
890 
891 typedef enum MachineInitPhase {
892     /* current_machine is NULL.  */
893     PHASE_NO_MACHINE,
894 
895     /* current_machine is not NULL, but current_machine->accel is NULL.  */
896     PHASE_MACHINE_CREATED,
897 
898     /*
899      * current_machine->accel is not NULL, but the machine properties have
900      * not been validated and machine_class->init has not yet been called.
901      */
902     PHASE_ACCEL_CREATED,
903 
904     /*
905      * machine_class->init has been called, thus creating any embedded
906      * devices and validating machine properties.  Devices created at
907      * this time are considered to be cold-plugged.
908      */
909     PHASE_MACHINE_INITIALIZED,
910 
911     /*
912      * QEMU is ready to start CPUs and devices created at this time
913      * are considered to be hot-plugged.  The monitor is not restricted
914      * to "preconfig" commands.
915      */
916     PHASE_MACHINE_READY,
917 } MachineInitPhase;
918 
919 extern bool phase_check(MachineInitPhase phase);
920 extern void phase_advance(MachineInitPhase phase);
921 
922 #endif
923