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54
55 package ti.sysbios.knl;
56
57 import xdc.rov.ViewInfo;
58
59 import xdc.runtime.Assert;
60 import xdc.runtime.Diags;
61 import xdc.runtime.Log;
62
63 import ti.sysbios.knl.Queue;
64 import ti.sysbios.knl.Clock;
65 import ti.sysbios.knl.Task;
66
67 /*!
68 * ======== Event ========
69 * Event Manager.
70 *
71 * SYS/BIOS events are a means of communication between Tasks and other
72 * threads such as Hwis, Swis, and other Tasks, or between Tasks and
73 * other SYS/BIOS objects. Other SYS/BIOS objects include semaphores,
74 * mailboxes,
75 * message queues, etc. Only tasks can wait for events; whereas tasks,
76 * Hwis, Swis, or SYS/BIOS objects can post them.
77 *
78 * In order for a task to be notified of an event from a SYS/BIOS object an
79 * event object must first be registered with that object. Separate APIs
80 * are provided (in their respective modules) for each of the SYS/BIOS object
81 * types that support this feature.
82 *
83 * Events are synchronous in nature, meaning that a receiving task will
84 * block or pend while waiting for the events to occur. When the desired
85 * events are received, the pending task continues its execution, as it
86 * would after a call to Semaphore_pend(), for example.
87 *
88 * Tasks can also wait on events that are not linked to other SYS/BIOS objects.
89 * These events are explicitly posted from other threads such as tasks,
90 * Swis, or Hwis. A task does not register to receive these events; the
91 * sending thread simply posts its event(s) to the event object the task
92 * is pending on. This scenario is similar to having an ISR post a
93 * semaphore.
94 *
95 * A task can wait on events from multiple resources and/or threads; thus,
96 * it can be waiting for a semaphore to be posted and for a message to
97 * arrive in a message queue or an ISR thread to signal that an event has
98 * occurred.
99 *
100 * Events are binary. Events become available (posted) on each Event_post()
101 * of the eventId and become non-available (consumed) on each qualifying
102 * Event_pend() mask.
103 *
104 * Unlike Semaphores, only a single task can pend on an Event object.
105 *
106 * {@link #pend} is used to wait for events. The andMask & orMask
107 * determine which
108 * event(s) must occur before returning from {@link #pend}. The timeout
109 * parameter
110 * allows the task to wait until a timeout, wait indefinitely, or not wait
111 * at all. A return value of zero indicates that a timeout has occurred. A
112 * non-zero return value is the set of events that were active at the time
113 * the task was unblocked.
114 *
115 * The andMask defines a set of events that must ALL occur to allow
116 * {@link #pend} to return.
117 *
118 * The orMask defines a set of events that will cause {@link #pend} to
119 * return if ANY of them occur.
120 *
121 * All active events present in the orMask are consumed (ie removed from
122 * the event object) upon return from {@link #pend}. Only when all events
123 * present in the andMask are active are they consumed on return from
124 * {@link #pend}.
125 *
126 * {@link #pend} returns immediately if the andMask OR orMask conditions
127 * are true upon entry.
128 *
129 * {@link #post} is used to signal events. If a task is waiting for the event
130 * and all of the event conditions are met, {@link #post} unblocks the task.
131 * If no task is waiting, {@link #post} simply registers the event with the
132 * event object and returns.
133 *
134 * The maximum number of eventIds supported is target specific and depends
135 * on the number of bits in a UInt data type.
136 * For 6x and ARM devices the maximum number of eventIds is therefore 32.
137 * For 28x and MSP430 devices, the maximum number of eventIds is 16.
138 *
139 * @p(html)
140 * <h3> Calling Context </h3>
141 * <table border="1" cellpadding="3">
142 * <colgroup span="1"></colgroup> <colgroup span="5" align="center">
143 * </colgroup>
144 *
145 * <tr><th> Function </th><th> Hwi </th><th> Swi </th>
146 * <th> Task </th><th> Main </th><th> Startup </th></tr>
147 * <!-- -->
148 * <tr><td> {@link #create} </td><td> N </td><td> N </td>
149 * <td> Y </td><td> Y </td><td> N </td></tr>
150 * <tr><td> {@link #Params_init} </td><td> Y </td><td> Y </td>
151 * <td> Y </td><td> Y </td><td> Y </td></tr>
152 * <tr><td> {@link #construct} </td><td> N </td><td> N </td>
153 * <td> Y </td><td> Y </td><td> N </td></tr>
154 * <tr><td> {@link #delete} </td><td> N </td><td> N </td>
155 * <td> Y </td><td> Y </td><td> N </td></tr>
156 * <tr><td> {@link #destruct} </td><td> N </td><td> N </td>
157 * <td> Y </td><td> Y </td><td> N </td></tr>
158 * <tr><td> {@link #getPostedEvents} </td><td> Y </td><td> Y </td>
159 * <td> Y </td><td> Y </td><td> Y </td></tr>
160 * <tr><td> {@link #pend} </td><td> N* </td><td> N* </td>
161 * <td> Y </td><td> N* </td><td> N </td></tr>
162 * <tr><td> {@link #post} </td><td> Y </td><td> Y </td>
163 * <td> Y </td><td> Y </td><td> N </td></tr>
164 * <tr><td colspan="6"> Definitions: (N* means OK to call iff the timeout
165 * parameter is set to '0'.)<br />
166 * <ul>
167 * <li> <b>Hwi</b>: API is callable from a Hwi thread. </li>
168 * <li> <b>Swi</b>: API is callable from a Swi thread. </li>
169 * <li> <b>Task</b>: API is callable from a Task thread. </li>
170 * <li> <b>Main</b>: API is callable during any of these phases: </li>
171 * <ul>
172 * <li> In your module startup after this module is started
173 * (e.g. Event_Module_startupDone() returns TRUE). </li>
174 * <li> During xdc.runtime.Startup.lastFxns. </li>
175 * <li> During main().</li>
176 * <li> During BIOS.startupFxns.</li>
177 * </ul>
178 * <li> <b>Startup</b>: API is callable during any of these phases:</li>
179 * <ul>
180 * <li> During xdc.runtime.Startup.firstFxns.</li>
181 * <li> In your module startup before this module is started
182 * (e.g. Event_Module_startupDone() returns FALSE).</li>
183 * </ul>
184 * </ul>
185 * </td></tr>
186 *
187 * </table>
188 * @p
189 */
190
191 @DirectCall
192 193 194
195 @CustomHeader
196 @InstanceInitStatic
197
198 module Event
199 {
200 /*!
201 * Pre-defined Event Ids
202 *
203 * Event_Ids are provided to simplify the specification of
204 * andMasks and orMasks arguments to {@link #pend Event_pend()}.
205 *
206 * Since each Event_Id is a bitmask composed of only a single bit,
207 * a group of Event_Ids within an andMask or orMask can be indicated
208 * by simply adding them together. For instance, to indicate that a task
209 * is to be awakened only when both Event_Id_00 and Event_Id_01 have
210 * been posted, the andMask for Event_pend() would be constructed
211 * as below:
212 *
213 * @p(code)
214 * Event_pend(event, Event_Id_00+EventId_01, Event_Id_NONE,
215 * BIOS_WAIT_FOREVER);
216 * @p
217 *
218 * As shown above, Event_Id_NONE is to be used as an empty (NULL)
219 * andMask or orMask.
220 *
221 * @a(Note)
222 * For targets where a UInt is 32 bits in length,
223 * Event_Id_00 thru Event_Id_31 can be used.
224 *
225 * For targets where a UInt is 16 bits in length,
226 * Event_Id_00 thru Event_Id_15 can be used.
227 */
228
229 const UInt Id_00 = 0x1;
230 const UInt Id_01 = 0x2; /*! @see #Id_00 Pre-defined Event IDs. */
231 const UInt Id_02 = 0x4; /*! @see #Id_00 Pre-defined Event IDs. */
232 const UInt Id_03 = 0x8; /*! @see #Id_00 Pre-defined Event IDs. */
233 const UInt Id_04 = 0x10; /*! @see #Id_00 Pre-defined Event IDs. */
234 const UInt Id_05 = 0x20; /*! @see #Id_00 Pre-defined Event IDs. */
235 const UInt Id_06 = 0x40; /*! @see #Id_00 Pre-defined Event IDs. */
236 const UInt Id_07 = 0x80; /*! @see #Id_00 Pre-defined Event IDs. */
237 const UInt Id_08 = 0x100; /*! @see #Id_00 Pre-defined Event IDs. */
238 const UInt Id_09 = 0x200; /*! @see #Id_00 Pre-defined Event IDs. */
239 const UInt Id_10 = 0x400; /*! @see #Id_00 Pre-defined Event IDs. */
240 const UInt Id_11 = 0x800; /*! @see #Id_00 Pre-defined Event IDs. */
241 const UInt Id_12 = 0x1000; /*! @see #Id_00 Pre-defined Event IDs. */
242 const UInt Id_13 = 0x2000; /*! @see #Id_00 Pre-defined Event IDs. */
243 const UInt Id_14 = 0x4000; /*! @see #Id_00 Pre-defined Event IDs. */
244 const UInt Id_15 = 0x8000; /*! @see #Id_00 Pre-defined Event IDs. */
245 const UInt Id_16 = 0x10000; /*! @see #Id_00 Pre-defined Event IDs. */
246 const UInt Id_17 = 0x20000; /*! @see #Id_00 Pre-defined Event IDs. */
247 const UInt Id_18 = 0x40000; /*! @see #Id_00 Pre-defined Event IDs. */
248 const UInt Id_19 = 0x80000; /*! @see #Id_00 Pre-defined Event IDs. */
249 const UInt Id_20 = 0x100000; /*! @see #Id_00 Pre-defined Event IDs. */
250 const UInt Id_21 = 0x200000; /*! @see #Id_00 Pre-defined Event IDs. */
251 const UInt Id_22 = 0x400000; /*! @see #Id_00 Pre-defined Event IDs. */
252 const UInt Id_23 = 0x800000; /*! @see #Id_00 Pre-defined Event IDs. */
253 const UInt Id_24 = 0x1000000; /*! @see #Id_00 Pre-defined Event IDs. */
254 const UInt Id_25 = 0x2000000; /*! @see #Id_00 Pre-defined Event IDs. */
255 const UInt Id_26 = 0x4000000; /*! @see #Id_00 Pre-defined Event IDs. */
256 const UInt Id_27 = 0x8000000; /*! @see #Id_00 Pre-defined Event IDs. */
257 const UInt Id_28 = 0x10000000; /*! @see #Id_00 Pre-defined Event IDs. */
258 const UInt Id_29 = 0x20000000; /*! @see #Id_00 Pre-defined Event IDs. */
259 const UInt Id_30 = 0x40000000; /*! @see #Id_00 Pre-defined Event IDs. */
260 const UInt Id_31 = 0x80000000; /*! @see #Id_00 Pre-defined Event IDs. */
261
262 const UInt Id_NONE = 0; /*! @see #Id_00 Pre-defined Event IDs. */
263 /*!
264 * ======== BasicView ========
265 * @_nodoc
266 */
267 metaonly struct BasicView {
268 String label;
269 String postedEvents;
270 String pendedTask;
271 String andMask;
272 String orMask;
273 String timeout;
274 };
275
276 /*!
277 * ======== rovViewInfo ========
278 * @_nodoc
279 */
280 @Facet
281 metaonly config ViewInfo.Instance rovViewInfo =
282 ViewInfo.create({
283 viewMap: [
284 ['Basic', {type: ViewInfo.INSTANCE, viewInitFxn: 'viewInitBasic',
285 structName: 'BasicView'}]
286 ]
287 });
288
289
290
291
292
293 /*! Logged on calls to Event_post() */
294 config Log.Event LM_post = {
295 mask: Diags.USER1 | Diags.USER2,
296 msg: "LM_post: event: 0x%x, currEvents: 0x%x, eventId: 0x%x"
297 };
298
299 /*! Logged on calls to Event_pend() */
300 config Log.Event LM_pend = {
301 mask: Diags.USER1 | Diags.USER2,
302 msg: "LM_pend: event: 0x%x, currEvents: 0x%x, andMask: 0x%x, orMask: 0x%x, timeout: %d"
303 };
304
305
306
307 /*!
308 * Asserted when {@link #pend} is called with andMask and orMask == 0
309 */
310 config Assert.Id A_nullEventMasks = {
311 msg: "A_nullEventMasks: orMask and andMask are null."
312 };
313
314 /*!
315 * Asserted when {@link #post} is called with eventId == 0
316 */
317 config Assert.Id A_nullEventId = {
318 msg: "A_nullEventId: posted eventId is null."
319 };
320
321 /*!
322 * Asserted when {@link #pend} is called by multiple tasks on the same
323 * Event object.
324 */
325 config Assert.Id A_eventInUse = {
326 msg: "A_eventInUse: Event object already in use."
327 };
328
329 /*!
330 * Asserted when {@link #pend} is called with non-zero timeout from other
331 * than a Task context.
332 */
333 config Assert.Id A_badContext = {
334 msg: "A_badContext: bad calling context. Must be called from a Task."
335 };
336
337 /*!
338 * ======== A_pendTaskDisabled ========
339 * Asserted in Event_pend()
340 *
341 * Assert raised if Event_pend() is called with the Task or
342 * Swi scheduler disabled.
343 */
344 config Assert.Id A_pendTaskDisabled = {
345 msg: "A_pendTaskDisabled: Cannot call Event_pend() while the Task or Swi scheduler is disabled."
346 };
347
348 instance:
349
350 /*!
351 * ======== create ========
352 * Create an Event object.
353 *
354 * This function creates a new Event object.
355 */
356 create();
357
358 /*!
359 * ======== pend ========
360 * Wait for events defined in 'and' OR 'or' masks.
361 *
362 * pend() is used to wait for events. The andMask and orMask determine
363 * which
364 * event(s) must occur before returning from pend(). The timeout parameter
365 * allows the task to wait until a timeout, wait indefinitely, or not wait
366 * at all. A return value of zero indicates that a timeout has occurred. A
367 * non-zero return value is the set of events that were active at the time
368 * the task was unblocked.
369 *
370 * The andMask defines a set of events that must
371 * ALL occur to allow pend() to return.
372 *
373 * The orMask defines a set of events
374 * that will cause pend() to return if ANY of them occur.
375 *
376 * All active events
377 * present in the orMask are consumed (i.e. removed from the event object)
378 * upon return from pend(). Only when all events present in the andMask
379 * are active are they consumed on return from pend().
380 *
381 * The pend conditions are satisfied when either ALL of the events
382 * in the andMask occur or ANY of the events in the orMask occur.
383 *
384 * A timeout value of
385 * {@link ti.sysbios.BIOS#WAIT_FOREVER, BIOS_WAIT_FOREVER} causes
386 * the task to wait indefinitely for matching events to be posted.
387 *
388 * A timeout value of {@link ti.sysbios.BIOS#NO_WAIT, BIOS_NO_WAIT}
389 * causes Event_pend to return immediately.
390 *
391 * @param(andMask) return from pend() when ALL of these
392 * events have occurred
393 * @param(orMask) return from pend() when ANY of these
394 * events have occurred
395 * @param(timeout) return from pend() after this many system
396 * time units
397 *
398 * @b(returns) All consumed events or zero if timeout.
399 */
400 UInt pend(UInt andMask, UInt orMask, UInt32 timeout);
401
402 /*!
403 * ======== post ========
404 * Post event(s) to an event object.
405 *
406 * Event_post() is used to signal events. If a task is waiting for the
407 * event and the event conditions are met, post() unblocks the
408 * task. If no tasks are waiting, post() simply registers the event with
409 * the event object and returns.
410 *
411 * @param(eventMask) mask of eventIds to post (must be non-zero)
412 */
413 Void post(UInt eventMask);
414
415 /*!
416 * ======== getPostedEvents ========
417 * Returns the set of events that have not been consumed by a task
418 * (ie those events that have not fully satisfied any pend() conditions).
419 * No events are consumed!
420 *
421 * @b(returns) All un-consumed events posted to the event.
422 */
423 UInt getPostedEvents();
424
425 /*!
426 * @_nodoc
427 * ======== sync ========
428 * synchronize an eventId to the value given
429 * must call with interrupts disabled
430 *
431 * @param(eventId) eventId to sync
432 * @param(count) count
433 */
434 Void sync(UInt eventId, UInt count);
435
436 /*!
437 * @_nodoc
438 * ======== syncMeta ========
439 * synchronize an eventId to the value given (static version)
440 *
441 * @param(eventId) eventId to sync
442 * @param(count) count
443 */
444 metaonly Void syncMeta(UInt eventId, UInt count);
445
446 internal:
447
448 /*!
449 * ======== pendTimeout ========
450 * This function is the clock event handler for pend
451 */
452 Void pendTimeout(UArg arg);
453
454 455 456 457 458 459 460
461 UInt checkEvents (Object *event, UInt andMask, UInt orMask);
462
463 464 465 466 467 468
469 metaonly config Any eventInstances[];
470
471
472 enum PendState {
473 PendState_TIMEOUT = 0,
474 PendState_POSTED = 1,
475 PendState_CLOCK_WAIT = 2,
476 PendState_WAIT_FOREVER = 3
477 };
478
479
480 struct PendElem {
481 Task.PendElem tpElem;
482 PendState pendState;
483 UInt matchingEvents;
484 UInt andMask;
485 UInt orMask;
486 };
487
488 struct Instance_State {
489 volatile UInt postedEvents;
490 Queue.Object pendQ;
491
492
493 };
494 }