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1 /******************************************************************************
2  *
3  * Module Name: evmisc - Miscellaneous event manager support functions
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2008, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43
44 #include <acpi/acpi.h>
45 #include <acpi/acevents.h>
46 #include <acpi/acnamesp.h>
47 #include <acpi/acinterp.h>
48
49 #define _COMPONENT          ACPI_EVENTS
50 ACPI_MODULE_NAME("evmisc")
51
52 /* Pointer to FACS needed for the Global Lock */
53 static struct acpi_table_facs *facs = NULL;
54
55 /* Local prototypes */
56
57 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context);
58
59 static u32 acpi_ev_global_lock_handler(void *context);
60
61 static acpi_status acpi_ev_remove_global_lock_handler(void);
62
63 /*******************************************************************************
64  *
65  * FUNCTION:    acpi_ev_is_notify_object
66  *
67  * PARAMETERS:  Node            - Node to check
68  *
69  * RETURN:      TRUE if notifies allowed on this object
70  *
71  * DESCRIPTION: Check type of node for a object that supports notifies.
72  *
73  *              TBD: This could be replaced by a flag bit in the node.
74  *
75  ******************************************************************************/
76
77 u8 acpi_ev_is_notify_object(struct acpi_namespace_node *node)
78 {
79         switch (node->type) {
80         case ACPI_TYPE_DEVICE:
81         case ACPI_TYPE_PROCESSOR:
82         case ACPI_TYPE_THERMAL:
83                 /*
84                  * These are the ONLY objects that can receive ACPI notifications
85                  */
86                 return (TRUE);
87
88         default:
89                 return (FALSE);
90         }
91 }
92
93 /*******************************************************************************
94  *
95  * FUNCTION:    acpi_ev_queue_notify_request
96  *
97  * PARAMETERS:  Node            - NS node for the notified object
98  *              notify_value    - Value from the Notify() request
99  *
100  * RETURN:      Status
101  *
102  * DESCRIPTION: Dispatch a device notification event to a previously
103  *              installed handler.
104  *
105  ******************************************************************************/
106
107 acpi_status
108 acpi_ev_queue_notify_request(struct acpi_namespace_node * node,
109                              u32 notify_value)
110 {
111         union acpi_operand_object *obj_desc;
112         union acpi_operand_object *handler_obj = NULL;
113         union acpi_generic_state *notify_info;
114         acpi_status status = AE_OK;
115
116         ACPI_FUNCTION_NAME(ev_queue_notify_request);
117
118         /*
119          * For value 3 (Ejection Request), some device method may need to be run.
120          * For value 2 (Device Wake) if _PRW exists, the _PS0 method may need
121          *   to be run.
122          * For value 0x80 (Status Change) on the power button or sleep button,
123          *   initiate soft-off or sleep operation?
124          */
125         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
126                           "Dispatching Notify on [%4.4s] Node %p Value 0x%2.2X (%s)\n",
127                           acpi_ut_get_node_name(node), node, notify_value,
128                           acpi_ut_get_notify_name(notify_value)));
129
130         /* Get the notify object attached to the NS Node */
131
132         obj_desc = acpi_ns_get_attached_object(node);
133         if (obj_desc) {
134
135                 /* We have the notify object, Get the right handler */
136
137                 switch (node->type) {
138
139                         /* Notify allowed only on these types */
140
141                 case ACPI_TYPE_DEVICE:
142                 case ACPI_TYPE_THERMAL:
143                 case ACPI_TYPE_PROCESSOR:
144
145                         if (notify_value <= ACPI_MAX_SYS_NOTIFY) {
146                                 handler_obj =
147                                     obj_desc->common_notify.system_notify;
148                         } else {
149                                 handler_obj =
150                                     obj_desc->common_notify.device_notify;
151                         }
152                         break;
153
154                 default:
155                         /* All other types are not supported */
156                         return (AE_TYPE);
157                 }
158         }
159
160         /*
161          * If there is any handler to run, schedule the dispatcher.
162          * Check for:
163          * 1) Global system notify handler
164          * 2) Global device notify handler
165          * 3) Per-device notify handler
166          */
167         if ((acpi_gbl_system_notify.handler
168              && (notify_value <= ACPI_MAX_SYS_NOTIFY))
169             || (acpi_gbl_device_notify.handler
170                 && (notify_value > ACPI_MAX_SYS_NOTIFY)) || handler_obj) {
171                 notify_info = acpi_ut_create_generic_state();
172                 if (!notify_info) {
173                         return (AE_NO_MEMORY);
174                 }
175
176                 if (!handler_obj) {
177                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
178                                           "Executing system notify handler for Notify (%4.4s, %X) node %p\n",
179                                           acpi_ut_get_node_name(node),
180                                           notify_value, node));
181                 }
182
183                 notify_info->common.descriptor_type =
184                     ACPI_DESC_TYPE_STATE_NOTIFY;
185                 notify_info->notify.node = node;
186                 notify_info->notify.value = (u16) notify_value;
187                 notify_info->notify.handler_obj = handler_obj;
188
189                 status =
190                     acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_ev_notify_dispatch,
191                                     notify_info);
192                 if (ACPI_FAILURE(status)) {
193                         acpi_ut_delete_generic_state(notify_info);
194                 }
195         } else {
196                 /*
197                  * There is no notify handler (per-device or system) for this device.
198                  */
199                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
200                                   "No notify handler for Notify (%4.4s, %X) node %p\n",
201                                   acpi_ut_get_node_name(node), notify_value,
202                                   node));
203         }
204
205         return (status);
206 }
207
208 /*******************************************************************************
209  *
210  * FUNCTION:    acpi_ev_notify_dispatch
211  *
212  * PARAMETERS:  Context         - To be passed to the notify handler
213  *
214  * RETURN:      None.
215  *
216  * DESCRIPTION: Dispatch a device notification event to a previously
217  *              installed handler.
218  *
219  ******************************************************************************/
220
221 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context)
222 {
223         union acpi_generic_state *notify_info =
224             (union acpi_generic_state *)context;
225         acpi_notify_handler global_handler = NULL;
226         void *global_context = NULL;
227         union acpi_operand_object *handler_obj;
228
229         ACPI_FUNCTION_ENTRY();
230
231         /*
232          * We will invoke a global notify handler if installed.
233          * This is done _before_ we invoke the per-device handler attached
234          * to the device.
235          */
236         if (notify_info->notify.value <= ACPI_MAX_SYS_NOTIFY) {
237
238                 /* Global system notification handler */
239
240                 if (acpi_gbl_system_notify.handler) {
241                         global_handler = acpi_gbl_system_notify.handler;
242                         global_context = acpi_gbl_system_notify.context;
243                 }
244         } else {
245                 /* Global driver notification handler */
246
247                 if (acpi_gbl_device_notify.handler) {
248                         global_handler = acpi_gbl_device_notify.handler;
249                         global_context = acpi_gbl_device_notify.context;
250                 }
251         }
252
253         /* Invoke the system handler first, if present */
254
255         if (global_handler) {
256                 global_handler(notify_info->notify.node,
257                                notify_info->notify.value, global_context);
258         }
259
260         /* Now invoke the per-device handler, if present */
261
262         handler_obj = notify_info->notify.handler_obj;
263         if (handler_obj) {
264                 handler_obj->notify.handler(notify_info->notify.node,
265                                             notify_info->notify.value,
266                                             handler_obj->notify.context);
267         }
268
269         /* All done with the info object */
270
271         acpi_ut_delete_generic_state(notify_info);
272 }
273
274 /*******************************************************************************
275  *
276  * FUNCTION:    acpi_ev_global_lock_handler
277  *
278  * PARAMETERS:  Context         - From thread interface, not used
279  *
280  * RETURN:      ACPI_INTERRUPT_HANDLED
281  *
282  * DESCRIPTION: Invoked directly from the SCI handler when a global lock
283  *              release interrupt occurs. Attempt to acquire the global lock,
284  *              if successful, signal the thread waiting for the lock.
285  *
286  * NOTE: Assumes that the semaphore can be signaled from interrupt level. If
287  * this is not possible for some reason, a separate thread will have to be
288  * scheduled to do this.
289  *
290  ******************************************************************************/
291
292 static u32 acpi_ev_global_lock_handler(void *context)
293 {
294         u8 acquired = FALSE;
295
296         /*
297          * Attempt to get the lock.
298          *
299          * If we don't get it now, it will be marked pending and we will
300          * take another interrupt when it becomes free.
301          */
302         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
303         if (acquired) {
304
305                 /* Got the lock, now wake all threads waiting for it */
306
307                 acpi_gbl_global_lock_acquired = TRUE;
308                 /* Send a unit to the semaphore */
309
310                 if (ACPI_FAILURE
311                     (acpi_os_signal_semaphore
312                      (acpi_gbl_global_lock_semaphore, 1))) {
313                         ACPI_ERROR((AE_INFO,
314                                     "Could not signal Global Lock semaphore"));
315                 }
316         }
317
318         return (ACPI_INTERRUPT_HANDLED);
319 }
320
321 /*******************************************************************************
322  *
323  * FUNCTION:    acpi_ev_init_global_lock_handler
324  *
325  * PARAMETERS:  None
326  *
327  * RETURN:      Status
328  *
329  * DESCRIPTION: Install a handler for the global lock release event
330  *
331  ******************************************************************************/
332
333 acpi_status acpi_ev_init_global_lock_handler(void)
334 {
335         acpi_status status;
336
337         ACPI_FUNCTION_TRACE(ev_init_global_lock_handler);
338
339         status = acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
340                                          ACPI_CAST_INDIRECT_PTR(struct
341                                                                 acpi_table_header,
342                                                                 &facs));
343         if (ACPI_FAILURE(status)) {
344                 return_ACPI_STATUS(status);
345         }
346
347         acpi_gbl_global_lock_present = TRUE;
348         status = acpi_install_fixed_event_handler(ACPI_EVENT_GLOBAL,
349                                                   acpi_ev_global_lock_handler,
350                                                   NULL);
351
352         /*
353          * If the global lock does not exist on this platform, the attempt
354          * to enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick)
355          * Map to AE_OK, but mark global lock as not present.
356          * Any attempt to actually use the global lock will be flagged
357          * with an error.
358          */
359         if (status == AE_NO_HARDWARE_RESPONSE) {
360                 ACPI_ERROR((AE_INFO,
361                             "No response from Global Lock hardware, disabling lock"));
362
363                 acpi_gbl_global_lock_present = FALSE;
364                 status = AE_OK;
365         }
366
367         return_ACPI_STATUS(status);
368 }
369
370 /*******************************************************************************
371  *
372  * FUNCTION:    acpi_ev_remove_global_lock_handler
373  *
374  * PARAMETERS:  None
375  *
376  * RETURN:      Status
377  *
378  * DESCRIPTION: Remove the handler for the Global Lock
379  *
380  ******************************************************************************/
381
382 static acpi_status acpi_ev_remove_global_lock_handler(void)
383 {
384         acpi_status status;
385
386         ACPI_FUNCTION_TRACE(ev_remove_global_lock_handler);
387
388         acpi_gbl_global_lock_present = FALSE;
389         status = acpi_remove_fixed_event_handler(ACPI_EVENT_GLOBAL,
390                                                  acpi_ev_global_lock_handler);
391
392         return_ACPI_STATUS(status);
393 }
394
395 /******************************************************************************
396  *
397  * FUNCTION:    acpi_ev_acquire_global_lock
398  *
399  * PARAMETERS:  Timeout         - Max time to wait for the lock, in millisec.
400  *
401  * RETURN:      Status
402  *
403  * DESCRIPTION: Attempt to gain ownership of the Global Lock.
404  *
405  * MUTEX:       Interpreter must be locked
406  *
407  * Note: The original implementation allowed multiple threads to "acquire" the
408  * Global Lock, and the OS would hold the lock until the last thread had
409  * released it. However, this could potentially starve the BIOS out of the
410  * lock, especially in the case where there is a tight handshake between the
411  * Embedded Controller driver and the BIOS. Therefore, this implementation
412  * allows only one thread to acquire the HW Global Lock at a time, and makes
413  * the global lock appear as a standard mutex on the OS side.
414  *
415  *****************************************************************************/
416 static acpi_thread_id acpi_ev_global_lock_thread_id;
417 static int acpi_ev_global_lock_acquired;
418
419 acpi_status acpi_ev_acquire_global_lock(u16 timeout)
420 {
421         acpi_status status = AE_OK;
422         u8 acquired = FALSE;
423
424         ACPI_FUNCTION_TRACE(ev_acquire_global_lock);
425
426         /*
427          * Only one thread can acquire the GL at a time, the global_lock_mutex
428          * enforces this. This interface releases the interpreter if we must wait.
429          */
430         status = acpi_ex_system_wait_mutex(
431                         acpi_gbl_global_lock_mutex->mutex.os_mutex, 0);
432         if (status == AE_TIME) {
433                 if (acpi_ev_global_lock_thread_id == acpi_os_get_thread_id()) {
434                         acpi_ev_global_lock_acquired++;
435                         return AE_OK;
436                 }
437         }
438
439         if (ACPI_FAILURE(status)) {
440                 status = acpi_ex_system_wait_mutex(
441                                 acpi_gbl_global_lock_mutex->mutex.os_mutex,
442                                 timeout);
443         }
444         if (ACPI_FAILURE(status)) {
445                 return_ACPI_STATUS(status);
446         }
447
448         acpi_ev_global_lock_thread_id = acpi_os_get_thread_id();
449         acpi_ev_global_lock_acquired++;
450
451         /*
452          * Update the global lock handle and check for wraparound. The handle is
453          * only used for the external global lock interfaces, but it is updated
454          * here to properly handle the case where a single thread may acquire the
455          * lock via both the AML and the acpi_acquire_global_lock interfaces. The
456          * handle is therefore updated on the first acquire from a given thread
457          * regardless of where the acquisition request originated.
458          */
459         acpi_gbl_global_lock_handle++;
460         if (acpi_gbl_global_lock_handle == 0) {
461                 acpi_gbl_global_lock_handle = 1;
462         }
463
464         /*
465          * Make sure that a global lock actually exists. If not, just treat
466          * the lock as a standard mutex.
467          */
468         if (!acpi_gbl_global_lock_present) {
469                 acpi_gbl_global_lock_acquired = TRUE;
470                 return_ACPI_STATUS(AE_OK);
471         }
472
473         /* Attempt to acquire the actual hardware lock */
474
475         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
476         if (acquired) {
477
478                 /* We got the lock */
479
480                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
481                                   "Acquired hardware Global Lock\n"));
482
483                 acpi_gbl_global_lock_acquired = TRUE;
484                 return_ACPI_STATUS(AE_OK);
485         }
486
487         /*
488          * Did not get the lock. The pending bit was set above, and we must now
489          * wait until we get the global lock released interrupt.
490          */
491         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Waiting for hardware Global Lock\n"));
492
493         /*
494          * Wait for handshake with the global lock interrupt handler.
495          * This interface releases the interpreter if we must wait.
496          */
497         status = acpi_ex_system_wait_semaphore(acpi_gbl_global_lock_semaphore,
498                                                ACPI_WAIT_FOREVER);
499
500         return_ACPI_STATUS(status);
501 }
502
503 /*******************************************************************************
504  *
505  * FUNCTION:    acpi_ev_release_global_lock
506  *
507  * PARAMETERS:  None
508  *
509  * RETURN:      Status
510  *
511  * DESCRIPTION: Releases ownership of the Global Lock.
512  *
513  ******************************************************************************/
514
515 acpi_status acpi_ev_release_global_lock(void)
516 {
517         u8 pending = FALSE;
518         acpi_status status = AE_OK;
519
520         ACPI_FUNCTION_TRACE(ev_release_global_lock);
521
522         /* Lock must be already acquired */
523
524         if (!acpi_gbl_global_lock_acquired) {
525                 ACPI_WARNING((AE_INFO,
526                               "Cannot release the ACPI Global Lock, it has not been acquired"));
527                 return_ACPI_STATUS(AE_NOT_ACQUIRED);
528         }
529
530         acpi_ev_global_lock_acquired--;
531         if (acpi_ev_global_lock_acquired > 0) {
532                 return AE_OK;
533         }
534
535         if (acpi_gbl_global_lock_present) {
536
537                 /* Allow any thread to release the lock */
538
539                 ACPI_RELEASE_GLOBAL_LOCK(facs, pending);
540
541                 /*
542                  * If the pending bit was set, we must write GBL_RLS to the control
543                  * register
544                  */
545                 if (pending) {
546                         status =
547                             acpi_set_register(ACPI_BITREG_GLOBAL_LOCK_RELEASE,
548                                               1);
549                 }
550
551                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
552                                   "Released hardware Global Lock\n"));
553         }
554
555         acpi_gbl_global_lock_acquired = FALSE;
556
557         /* Release the local GL mutex */
558         acpi_ev_global_lock_thread_id = NULL;
559         acpi_ev_global_lock_acquired = 0;
560         acpi_os_release_mutex(acpi_gbl_global_lock_mutex->mutex.os_mutex);
561         return_ACPI_STATUS(status);
562 }
563
564 /******************************************************************************
565  *
566  * FUNCTION:    acpi_ev_terminate
567  *
568  * PARAMETERS:  none
569  *
570  * RETURN:      none
571  *
572  * DESCRIPTION: Disable events and free memory allocated for table storage.
573  *
574  ******************************************************************************/
575
576 void acpi_ev_terminate(void)
577 {
578         u32 i;
579         acpi_status status;
580
581         ACPI_FUNCTION_TRACE(ev_terminate);
582
583         if (acpi_gbl_events_initialized) {
584                 /*
585                  * Disable all event-related functionality.
586                  * In all cases, on error, print a message but obviously we don't abort.
587                  */
588
589                 /* Disable all fixed events */
590
591                 for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++) {
592                         status = acpi_disable_event(i, 0);
593                         if (ACPI_FAILURE(status)) {
594                                 ACPI_ERROR((AE_INFO,
595                                             "Could not disable fixed event %d",
596                                             (u32) i));
597                         }
598                 }
599
600                 /* Disable all GPEs in all GPE blocks */
601
602                 status = acpi_ev_walk_gpe_list(acpi_hw_disable_gpe_block);
603
604                 /* Remove SCI handler */
605
606                 status = acpi_ev_remove_sci_handler();
607                 if (ACPI_FAILURE(status)) {
608                         ACPI_ERROR((AE_INFO, "Could not remove SCI handler"));
609                 }
610
611                 status = acpi_ev_remove_global_lock_handler();
612                 if (ACPI_FAILURE(status)) {
613                         ACPI_ERROR((AE_INFO,
614                                     "Could not remove Global Lock handler"));
615                 }
616         }
617
618         /* Deallocate all handler objects installed within GPE info structs */
619
620         status = acpi_ev_walk_gpe_list(acpi_ev_delete_gpe_handlers);
621
622         /* Return to original mode if necessary */
623
624         if (acpi_gbl_original_mode == ACPI_SYS_MODE_LEGACY) {
625                 status = acpi_disable();
626                 if (ACPI_FAILURE(status)) {
627                         ACPI_WARNING((AE_INFO, "AcpiDisable failed"));
628                 }
629         }
630         return_VOID;
631 }