xref: /qemu/include/hw/qdev-core.h (revision 1a37eca107cece3ed454bae29eef0bd1fac4a244)
1074a86fcSAnthony Liguori #ifndef QDEV_CORE_H
2074a86fcSAnthony Liguori #define QDEV_CORE_H
3074a86fcSAnthony Liguori 
41de7afc9SPaolo Bonzini #include "qemu/queue.h"
51de7afc9SPaolo Bonzini #include "qemu/option.h"
61de7afc9SPaolo Bonzini #include "qemu/typedefs.h"
7949fc823SMarcel Apfelbaum #include "qemu/bitmap.h"
814cccb61SPaolo Bonzini #include "qom/object.h"
9074a86fcSAnthony Liguori #include "hw/irq.h"
107b1b5d19SPaolo Bonzini #include "qapi/error.h"
110ee4de6cSIgor Mammedov #include "hw/hotplug.h"
12074a86fcSAnthony Liguori 
13074a86fcSAnthony Liguori enum {
14074a86fcSAnthony Liguori     DEV_NVECTORS_UNSPECIFIED = -1,
15074a86fcSAnthony Liguori };
16074a86fcSAnthony Liguori 
17074a86fcSAnthony Liguori #define TYPE_DEVICE "device"
18074a86fcSAnthony Liguori #define DEVICE(obj) OBJECT_CHECK(DeviceState, (obj), TYPE_DEVICE)
19074a86fcSAnthony Liguori #define DEVICE_CLASS(klass) OBJECT_CLASS_CHECK(DeviceClass, (klass), TYPE_DEVICE)
20074a86fcSAnthony Liguori #define DEVICE_GET_CLASS(obj) OBJECT_GET_CLASS(DeviceClass, (obj), TYPE_DEVICE)
21074a86fcSAnthony Liguori 
223d1237fbSMarcel Apfelbaum typedef enum DeviceCategory {
233d1237fbSMarcel Apfelbaum     DEVICE_CATEGORY_BRIDGE,
243d1237fbSMarcel Apfelbaum     DEVICE_CATEGORY_USB,
253d1237fbSMarcel Apfelbaum     DEVICE_CATEGORY_STORAGE,
263d1237fbSMarcel Apfelbaum     DEVICE_CATEGORY_NETWORK,
273d1237fbSMarcel Apfelbaum     DEVICE_CATEGORY_INPUT,
283d1237fbSMarcel Apfelbaum     DEVICE_CATEGORY_DISPLAY,
293d1237fbSMarcel Apfelbaum     DEVICE_CATEGORY_SOUND,
303d1237fbSMarcel Apfelbaum     DEVICE_CATEGORY_MISC,
313d1237fbSMarcel Apfelbaum     DEVICE_CATEGORY_MAX
323d1237fbSMarcel Apfelbaum } DeviceCategory;
333d1237fbSMarcel Apfelbaum 
34074a86fcSAnthony Liguori typedef int (*qdev_initfn)(DeviceState *dev);
35074a86fcSAnthony Liguori typedef int (*qdev_event)(DeviceState *dev);
36074a86fcSAnthony Liguori typedef void (*qdev_resetfn)(DeviceState *dev);
37249d4172SAndreas Färber typedef void (*DeviceRealize)(DeviceState *dev, Error **errp);
38249d4172SAndreas Färber typedef void (*DeviceUnrealize)(DeviceState *dev, Error **errp);
39074a86fcSAnthony Liguori 
40074a86fcSAnthony Liguori struct VMStateDescription;
41074a86fcSAnthony Liguori 
42249d4172SAndreas Färber /**
43249d4172SAndreas Färber  * DeviceClass:
44249d4172SAndreas Färber  * @props: Properties accessing state fields.
45249d4172SAndreas Färber  * @realize: Callback function invoked when the #DeviceState:realized
46249d4172SAndreas Färber  * property is changed to %true. The default invokes @init if not %NULL.
47249d4172SAndreas Färber  * @unrealize: Callback function invoked when the #DeviceState:realized
48249d4172SAndreas Färber  * property is changed to %false.
49249d4172SAndreas Färber  * @init: Callback function invoked when the #DeviceState::realized property
50249d4172SAndreas Färber  * is changed to %true. Deprecated, new types inheriting directly from
51249d4172SAndreas Färber  * TYPE_DEVICE should use @realize instead, new leaf types should consult
52249d4172SAndreas Färber  * their respective parent type.
53*1a37eca1SIgor Mammedov  * @hotpluggable: indicates if #DeviceClass is hotpluggable, available
54*1a37eca1SIgor Mammedov  * as readonly "hotpluggable" property of #DeviceState instance
55249d4172SAndreas Färber  *
56249d4172SAndreas Färber  * # Realization #
57249d4172SAndreas Färber  * Devices are constructed in two stages,
58249d4172SAndreas Färber  * 1) object instantiation via object_initialize() and
59249d4172SAndreas Färber  * 2) device realization via #DeviceState:realized property.
60249d4172SAndreas Färber  * The former may not fail (it might assert or exit), the latter may return
61249d4172SAndreas Färber  * error information to the caller and must be re-entrant.
62249d4172SAndreas Färber  * Trivial field initializations should go into #TypeInfo.instance_init.
63249d4172SAndreas Färber  * Operations depending on @props static properties should go into @realize.
64249d4172SAndreas Färber  * After successful realization, setting static properties will fail.
65249d4172SAndreas Färber  *
66249d4172SAndreas Färber  * As an interim step, the #DeviceState:realized property is set by deprecated
67249d4172SAndreas Färber  * functions qdev_init() and qdev_init_nofail().
68249d4172SAndreas Färber  * In the future, devices will propagate this state change to their children
69249d4172SAndreas Färber  * and along busses they expose.
70249d4172SAndreas Färber  * The point in time will be deferred to machine creation, so that values
71249d4172SAndreas Färber  * set in @realize will not be introspectable beforehand. Therefore devices
72249d4172SAndreas Färber  * must not create children during @realize; they should initialize them via
73249d4172SAndreas Färber  * object_initialize() in their own #TypeInfo.instance_init and forward the
74249d4172SAndreas Färber  * realization events appropriately.
75249d4172SAndreas Färber  *
76249d4172SAndreas Färber  * The @init callback is considered private to a particular bus implementation
77249d4172SAndreas Färber  * (immediate abstract child types of TYPE_DEVICE). Derived leaf types set an
78249d4172SAndreas Färber  * "init" callback on their parent class instead.
79782beb52SAndreas Färber  *
80249d4172SAndreas Färber  * Any type may override the @realize and/or @unrealize callbacks but needs
81782beb52SAndreas Färber  * to call the parent type's implementation if keeping their functionality
82782beb52SAndreas Färber  * is desired. Refer to QOM documentation for further discussion and examples.
83782beb52SAndreas Färber  *
84782beb52SAndreas Färber  * <note>
85782beb52SAndreas Färber  *   <para>
86249d4172SAndreas Färber  * If a type derived directly from TYPE_DEVICE implements @realize, it does
87249d4172SAndreas Färber  * not need to implement @init and therefore does not need to store and call
88249d4172SAndreas Färber  * #DeviceClass' default @realize callback.
89782beb52SAndreas Färber  * For other types consult the documentation and implementation of the
90782beb52SAndreas Färber  * respective parent types.
91782beb52SAndreas Färber  *   </para>
92782beb52SAndreas Färber  * </note>
93249d4172SAndreas Färber  */
94074a86fcSAnthony Liguori typedef struct DeviceClass {
95249d4172SAndreas Färber     /*< private >*/
96074a86fcSAnthony Liguori     ObjectClass parent_class;
97249d4172SAndreas Färber     /*< public >*/
98074a86fcSAnthony Liguori 
993d1237fbSMarcel Apfelbaum     DECLARE_BITMAP(categories, DEVICE_CATEGORY_MAX);
100074a86fcSAnthony Liguori     const char *fw_name;
101074a86fcSAnthony Liguori     const char *desc;
102074a86fcSAnthony Liguori     Property *props;
103efec3dd6SMarkus Armbruster 
104efec3dd6SMarkus Armbruster     /*
105efec3dd6SMarkus Armbruster      * Shall we hide this device model from -device / device_add?
106efec3dd6SMarkus Armbruster      * All devices should support instantiation with device_add, and
107efec3dd6SMarkus Armbruster      * this flag should not exist.  But we're not there, yet.  Some
108efec3dd6SMarkus Armbruster      * devices fail to instantiate with cryptic error messages.
109efec3dd6SMarkus Armbruster      * Others instantiate, but don't work.  Exposing users to such
110efec3dd6SMarkus Armbruster      * behavior would be cruel; this flag serves to protect them.  It
111efec3dd6SMarkus Armbruster      * should never be set without a comment explaining why it is set.
112efec3dd6SMarkus Armbruster      * TODO remove once we're there
113efec3dd6SMarkus Armbruster      */
114efec3dd6SMarkus Armbruster     bool cannot_instantiate_with_device_add_yet;
115*1a37eca1SIgor Mammedov     bool hotpluggable;
116074a86fcSAnthony Liguori 
117074a86fcSAnthony Liguori     /* callbacks */
118074a86fcSAnthony Liguori     void (*reset)(DeviceState *dev);
119249d4172SAndreas Färber     DeviceRealize realize;
120249d4172SAndreas Färber     DeviceUnrealize unrealize;
121074a86fcSAnthony Liguori 
122074a86fcSAnthony Liguori     /* device state */
123074a86fcSAnthony Liguori     const struct VMStateDescription *vmsd;
124074a86fcSAnthony Liguori 
125074a86fcSAnthony Liguori     /* Private to qdev / bus.  */
126249d4172SAndreas Färber     qdev_initfn init; /* TODO remove, once users are converted to realize */
127074a86fcSAnthony Liguori     qdev_event unplug;
128fe6c2117SAndreas Färber     qdev_event exit; /* TODO remove, once users are converted to unrealize */
129074a86fcSAnthony Liguori     const char *bus_type;
130074a86fcSAnthony Liguori } DeviceClass;
131074a86fcSAnthony Liguori 
1327983c8a3SAndreas Färber /**
1337983c8a3SAndreas Färber  * DeviceState:
1347983c8a3SAndreas Färber  * @realized: Indicates whether the device has been fully constructed.
1357983c8a3SAndreas Färber  *
1367983c8a3SAndreas Färber  * This structure should not be accessed directly.  We declare it here
1377983c8a3SAndreas Färber  * so that it can be embedded in individual device state structures.
1387983c8a3SAndreas Färber  */
139074a86fcSAnthony Liguori struct DeviceState {
1407983c8a3SAndreas Färber     /*< private >*/
141074a86fcSAnthony Liguori     Object parent_obj;
1427983c8a3SAndreas Färber     /*< public >*/
143074a86fcSAnthony Liguori 
144074a86fcSAnthony Liguori     const char *id;
1457983c8a3SAndreas Färber     bool realized;
146074a86fcSAnthony Liguori     QemuOpts *opts;
147074a86fcSAnthony Liguori     int hotplugged;
148074a86fcSAnthony Liguori     BusState *parent_bus;
149074a86fcSAnthony Liguori     int num_gpio_out;
150074a86fcSAnthony Liguori     qemu_irq *gpio_out;
151074a86fcSAnthony Liguori     int num_gpio_in;
152074a86fcSAnthony Liguori     qemu_irq *gpio_in;
153074a86fcSAnthony Liguori     QLIST_HEAD(, BusState) child_bus;
154074a86fcSAnthony Liguori     int num_child_bus;
155074a86fcSAnthony Liguori     int instance_id_alias;
156074a86fcSAnthony Liguori     int alias_required_for_version;
157074a86fcSAnthony Liguori };
158074a86fcSAnthony Liguori 
159074a86fcSAnthony Liguori #define TYPE_BUS "bus"
160074a86fcSAnthony Liguori #define BUS(obj) OBJECT_CHECK(BusState, (obj), TYPE_BUS)
161074a86fcSAnthony Liguori #define BUS_CLASS(klass) OBJECT_CLASS_CHECK(BusClass, (klass), TYPE_BUS)
162074a86fcSAnthony Liguori #define BUS_GET_CLASS(obj) OBJECT_GET_CLASS(BusClass, (obj), TYPE_BUS)
163074a86fcSAnthony Liguori 
164074a86fcSAnthony Liguori struct BusClass {
165074a86fcSAnthony Liguori     ObjectClass parent_class;
166074a86fcSAnthony Liguori 
167074a86fcSAnthony Liguori     /* FIXME first arg should be BusState */
168074a86fcSAnthony Liguori     void (*print_dev)(Monitor *mon, DeviceState *dev, int indent);
169074a86fcSAnthony Liguori     char *(*get_dev_path)(DeviceState *dev);
170074a86fcSAnthony Liguori     /*
171074a86fcSAnthony Liguori      * This callback is used to create Open Firmware device path in accordance
172074a86fcSAnthony Liguori      * with OF spec http://forthworks.com/standards/of1275.pdf. Individual bus
173074a86fcSAnthony Liguori      * bindings can be found at http://playground.sun.com/1275/bindings/.
174074a86fcSAnthony Liguori      */
175074a86fcSAnthony Liguori     char *(*get_fw_dev_path)(DeviceState *dev);
176dcc20931SPaolo Bonzini     void (*reset)(BusState *bus);
1771395af6fSKONRAD Frederic     /* maximum devices allowed on the bus, 0: no limit. */
1781395af6fSKONRAD Frederic     int max_dev;
179074a86fcSAnthony Liguori };
180074a86fcSAnthony Liguori 
181074a86fcSAnthony Liguori typedef struct BusChild {
182074a86fcSAnthony Liguori     DeviceState *child;
183074a86fcSAnthony Liguori     int index;
184074a86fcSAnthony Liguori     QTAILQ_ENTRY(BusChild) sibling;
185074a86fcSAnthony Liguori } BusChild;
186074a86fcSAnthony Liguori 
1870ee4de6cSIgor Mammedov #define QDEV_HOTPLUG_HANDLER_PROPERTY "hotplug-handler"
1880ee4de6cSIgor Mammedov 
189074a86fcSAnthony Liguori /**
190074a86fcSAnthony Liguori  * BusState:
1910ee4de6cSIgor Mammedov  * @hotplug_device: link to a hotplug device associated with bus.
192074a86fcSAnthony Liguori  */
193074a86fcSAnthony Liguori struct BusState {
194074a86fcSAnthony Liguori     Object obj;
195074a86fcSAnthony Liguori     DeviceState *parent;
196074a86fcSAnthony Liguori     const char *name;
197074a86fcSAnthony Liguori     int allow_hotplug;
1980ee4de6cSIgor Mammedov     HotplugHandler *hotplug_handler;
199074a86fcSAnthony Liguori     int max_index;
200074a86fcSAnthony Liguori     QTAILQ_HEAD(ChildrenHead, BusChild) children;
201074a86fcSAnthony Liguori     QLIST_ENTRY(BusState) sibling;
202074a86fcSAnthony Liguori };
203074a86fcSAnthony Liguori 
204074a86fcSAnthony Liguori struct Property {
205074a86fcSAnthony Liguori     const char   *name;
206074a86fcSAnthony Liguori     PropertyInfo *info;
207074a86fcSAnthony Liguori     int          offset;
208074a86fcSAnthony Liguori     uint8_t      bitnr;
209074a86fcSAnthony Liguori     uint8_t      qtype;
210074a86fcSAnthony Liguori     int64_t      defval;
2110be6bfacSPeter Maydell     int          arrayoffset;
2120be6bfacSPeter Maydell     PropertyInfo *arrayinfo;
2130be6bfacSPeter Maydell     int          arrayfieldsize;
214074a86fcSAnthony Liguori };
215074a86fcSAnthony Liguori 
216074a86fcSAnthony Liguori struct PropertyInfo {
217074a86fcSAnthony Liguori     const char *name;
218074a86fcSAnthony Liguori     const char *legacy_name;
219074a86fcSAnthony Liguori     const char **enum_table;
220074a86fcSAnthony Liguori     int (*parse)(DeviceState *dev, Property *prop, const char *str);
221074a86fcSAnthony Liguori     int (*print)(DeviceState *dev, Property *prop, char *dest, size_t len);
222074a86fcSAnthony Liguori     ObjectPropertyAccessor *get;
223074a86fcSAnthony Liguori     ObjectPropertyAccessor *set;
224074a86fcSAnthony Liguori     ObjectPropertyRelease *release;
225074a86fcSAnthony Liguori };
226074a86fcSAnthony Liguori 
227074a86fcSAnthony Liguori typedef struct GlobalProperty {
228074a86fcSAnthony Liguori     const char *driver;
229074a86fcSAnthony Liguori     const char *property;
230074a86fcSAnthony Liguori     const char *value;
231074a86fcSAnthony Liguori     QTAILQ_ENTRY(GlobalProperty) next;
232074a86fcSAnthony Liguori } GlobalProperty;
233074a86fcSAnthony Liguori 
234074a86fcSAnthony Liguori /*** Board API.  This should go away once we have a machine config file.  ***/
235074a86fcSAnthony Liguori 
236074a86fcSAnthony Liguori DeviceState *qdev_create(BusState *bus, const char *name);
237074a86fcSAnthony Liguori DeviceState *qdev_try_create(BusState *bus, const char *name);
238074a86fcSAnthony Liguori int qdev_init(DeviceState *dev) QEMU_WARN_UNUSED_RESULT;
239074a86fcSAnthony Liguori void qdev_init_nofail(DeviceState *dev);
240074a86fcSAnthony Liguori void qdev_set_legacy_instance_id(DeviceState *dev, int alias_id,
241074a86fcSAnthony Liguori                                  int required_for_version);
242074a86fcSAnthony Liguori void qdev_unplug(DeviceState *dev, Error **errp);
243074a86fcSAnthony Liguori int qdev_simple_unplug_cb(DeviceState *dev);
244074a86fcSAnthony Liguori void qdev_machine_creation_done(void);
245074a86fcSAnthony Liguori bool qdev_machine_modified(void);
246074a86fcSAnthony Liguori 
247074a86fcSAnthony Liguori qemu_irq qdev_get_gpio_in(DeviceState *dev, int n);
248074a86fcSAnthony Liguori void qdev_connect_gpio_out(DeviceState *dev, int n, qemu_irq pin);
249074a86fcSAnthony Liguori 
250074a86fcSAnthony Liguori BusState *qdev_get_child_bus(DeviceState *dev, const char *name);
251074a86fcSAnthony Liguori 
252074a86fcSAnthony Liguori /*** Device API.  ***/
253074a86fcSAnthony Liguori 
254074a86fcSAnthony Liguori /* Register device properties.  */
255074a86fcSAnthony Liguori /* GPIO inputs also double as IRQ sinks.  */
256074a86fcSAnthony Liguori void qdev_init_gpio_in(DeviceState *dev, qemu_irq_handler handler, int n);
257074a86fcSAnthony Liguori void qdev_init_gpio_out(DeviceState *dev, qemu_irq *pins, int n);
258074a86fcSAnthony Liguori 
259074a86fcSAnthony Liguori BusState *qdev_get_parent_bus(DeviceState *dev);
260074a86fcSAnthony Liguori 
261074a86fcSAnthony Liguori /*** BUS API. ***/
262074a86fcSAnthony Liguori 
263074a86fcSAnthony Liguori DeviceState *qdev_find_recursive(BusState *bus, const char *id);
264074a86fcSAnthony Liguori 
265074a86fcSAnthony Liguori /* Returns 0 to walk children, > 0 to skip walk, < 0 to terminate walk. */
266074a86fcSAnthony Liguori typedef int (qbus_walkerfn)(BusState *bus, void *opaque);
267074a86fcSAnthony Liguori typedef int (qdev_walkerfn)(DeviceState *dev, void *opaque);
268074a86fcSAnthony Liguori 
269fb17dfe0SAndreas Färber void qbus_create_inplace(void *bus, size_t size, const char *typename,
270074a86fcSAnthony Liguori                          DeviceState *parent, const char *name);
271074a86fcSAnthony Liguori BusState *qbus_create(const char *typename, DeviceState *parent, const char *name);
272074a86fcSAnthony Liguori /* Returns > 0 if either devfn or busfn skip walk somewhere in cursion,
273074a86fcSAnthony Liguori  *         < 0 if either devfn or busfn terminate walk somewhere in cursion,
274074a86fcSAnthony Liguori  *           0 otherwise. */
2750293214bSPaolo Bonzini int qbus_walk_children(BusState *bus,
2760293214bSPaolo Bonzini                        qdev_walkerfn *pre_devfn, qbus_walkerfn *pre_busfn,
2770293214bSPaolo Bonzini                        qdev_walkerfn *post_devfn, qbus_walkerfn *post_busfn,
2780293214bSPaolo Bonzini                        void *opaque);
2790293214bSPaolo Bonzini int qdev_walk_children(DeviceState *dev,
2800293214bSPaolo Bonzini                        qdev_walkerfn *pre_devfn, qbus_walkerfn *pre_busfn,
2810293214bSPaolo Bonzini                        qdev_walkerfn *post_devfn, qbus_walkerfn *post_busfn,
2820293214bSPaolo Bonzini                        void *opaque);
2830293214bSPaolo Bonzini 
284074a86fcSAnthony Liguori void qdev_reset_all(DeviceState *dev);
285d0508c36SPaolo Bonzini 
286d0508c36SPaolo Bonzini /**
287d0508c36SPaolo Bonzini  * @qbus_reset_all:
288d0508c36SPaolo Bonzini  * @bus: Bus to be reset.
289d0508c36SPaolo Bonzini  *
290d0508c36SPaolo Bonzini  * Reset @bus and perform a bus-level ("hard") reset of all devices connected
291d0508c36SPaolo Bonzini  * to it, including recursive processing of all buses below @bus itself.  A
292d0508c36SPaolo Bonzini  * hard reset means that qbus_reset_all will reset all state of the device.
293d0508c36SPaolo Bonzini  * For PCI devices, for example, this will include the base address registers
294d0508c36SPaolo Bonzini  * or configuration space.
295d0508c36SPaolo Bonzini  */
296d0508c36SPaolo Bonzini void qbus_reset_all(BusState *bus);
297074a86fcSAnthony Liguori void qbus_reset_all_fn(void *opaque);
298074a86fcSAnthony Liguori 
299074a86fcSAnthony Liguori /* This should go away once we get rid of the NULL bus hack */
300074a86fcSAnthony Liguori BusState *sysbus_get_default(void);
301074a86fcSAnthony Liguori 
302074a86fcSAnthony Liguori char *qdev_get_fw_dev_path(DeviceState *dev);
303074a86fcSAnthony Liguori 
304074a86fcSAnthony Liguori /**
305074a86fcSAnthony Liguori  * @qdev_machine_init
306074a86fcSAnthony Liguori  *
307074a86fcSAnthony Liguori  * Initialize platform devices before machine init.  This is a hack until full
308074a86fcSAnthony Liguori  * support for composition is added.
309074a86fcSAnthony Liguori  */
310074a86fcSAnthony Liguori void qdev_machine_init(void);
311074a86fcSAnthony Liguori 
312074a86fcSAnthony Liguori /**
313074a86fcSAnthony Liguori  * @device_reset
314074a86fcSAnthony Liguori  *
315074a86fcSAnthony Liguori  * Reset a single device (by calling the reset method).
316074a86fcSAnthony Liguori  */
317074a86fcSAnthony Liguori void device_reset(DeviceState *dev);
318074a86fcSAnthony Liguori 
319074a86fcSAnthony Liguori const struct VMStateDescription *qdev_get_vmsd(DeviceState *dev);
320074a86fcSAnthony Liguori 
321074a86fcSAnthony Liguori const char *qdev_fw_name(DeviceState *dev);
322074a86fcSAnthony Liguori 
323074a86fcSAnthony Liguori Object *qdev_get_machine(void);
324074a86fcSAnthony Liguori 
325074a86fcSAnthony Liguori /* FIXME: make this a link<> */
326074a86fcSAnthony Liguori void qdev_set_parent_bus(DeviceState *dev, BusState *bus);
327074a86fcSAnthony Liguori 
328074a86fcSAnthony Liguori extern int qdev_hotplug;
329074a86fcSAnthony Liguori 
330074a86fcSAnthony Liguori char *qdev_get_dev_path(DeviceState *dev);
331074a86fcSAnthony Liguori 
3320ee4de6cSIgor Mammedov static inline void qbus_set_hotplug_handler(BusState *bus, DeviceState *handler,
3330ee4de6cSIgor Mammedov                                             Error **errp)
3340ee4de6cSIgor Mammedov {
3350ee4de6cSIgor Mammedov     object_property_set_link(OBJECT(bus), OBJECT(handler),
3360ee4de6cSIgor Mammedov                              QDEV_HOTPLUG_HANDLER_PROPERTY, errp);
3370ee4de6cSIgor Mammedov     bus->allow_hotplug = 1;
3380ee4de6cSIgor Mammedov }
339074a86fcSAnthony Liguori #endif
340