Revert "ARM: tegra: tegratab: dummy change"
[linux-2.6.git] / drivers / acpi / acpica / psparse.c
1 /******************************************************************************
2  *
3  * Module Name: psparse - Parser top level AML parse routines
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2012, 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 /*
45  * Parse the AML and build an operation tree as most interpreters,
46  * like Perl, do.  Parsing is done by hand rather than with a YACC
47  * generated parser to tightly constrain stack and dynamic memory
48  * usage.  At the same time, parsing is kept flexible and the code
49  * fairly compact by parsing based on a list of AML opcode
50  * templates in aml_op_info[]
51  */
52
53 #include <acpi/acpi.h>
54 #include "accommon.h"
55 #include "acparser.h"
56 #include "acdispat.h"
57 #include "amlcode.h"
58 #include "acinterp.h"
59
60 #define _COMPONENT          ACPI_PARSER
61 ACPI_MODULE_NAME("psparse")
62
63 /*******************************************************************************
64  *
65  * FUNCTION:    acpi_ps_get_opcode_size
66  *
67  * PARAMETERS:  Opcode          - An AML opcode
68  *
69  * RETURN:      Size of the opcode, in bytes (1 or 2)
70  *
71  * DESCRIPTION: Get the size of the current opcode.
72  *
73  ******************************************************************************/
74 u32 acpi_ps_get_opcode_size(u32 opcode)
75 {
76
77         /* Extended (2-byte) opcode if > 255 */
78
79         if (opcode > 0x00FF) {
80                 return (2);
81         }
82
83         /* Otherwise, just a single byte opcode */
84
85         return (1);
86 }
87
88 /*******************************************************************************
89  *
90  * FUNCTION:    acpi_ps_peek_opcode
91  *
92  * PARAMETERS:  parser_state        - A parser state object
93  *
94  * RETURN:      Next AML opcode
95  *
96  * DESCRIPTION: Get next AML opcode (without incrementing AML pointer)
97  *
98  ******************************************************************************/
99
100 u16 acpi_ps_peek_opcode(struct acpi_parse_state * parser_state)
101 {
102         u8 *aml;
103         u16 opcode;
104
105         aml = parser_state->aml;
106         opcode = (u16) ACPI_GET8(aml);
107
108         if (opcode == AML_EXTENDED_OP_PREFIX) {
109
110                 /* Extended opcode, get the second opcode byte */
111
112                 aml++;
113                 opcode = (u16) ((opcode << 8) | ACPI_GET8(aml));
114         }
115
116         return (opcode);
117 }
118
119 /*******************************************************************************
120  *
121  * FUNCTION:    acpi_ps_complete_this_op
122  *
123  * PARAMETERS:  walk_state      - Current State
124  *              Op              - Op to complete
125  *
126  * RETURN:      Status
127  *
128  * DESCRIPTION: Perform any cleanup at the completion of an Op.
129  *
130  ******************************************************************************/
131
132 acpi_status
133 acpi_ps_complete_this_op(struct acpi_walk_state * walk_state,
134                          union acpi_parse_object * op)
135 {
136         union acpi_parse_object *prev;
137         union acpi_parse_object *next;
138         const struct acpi_opcode_info *parent_info;
139         union acpi_parse_object *replacement_op = NULL;
140         acpi_status status = AE_OK;
141
142         ACPI_FUNCTION_TRACE_PTR(ps_complete_this_op, op);
143
144         /* Check for null Op, can happen if AML code is corrupt */
145
146         if (!op) {
147                 return_ACPI_STATUS(AE_OK);      /* OK for now */
148         }
149
150         /* Delete this op and the subtree below it if asked to */
151
152         if (((walk_state->parse_flags & ACPI_PARSE_TREE_MASK) !=
153              ACPI_PARSE_DELETE_TREE)
154             || (walk_state->op_info->class == AML_CLASS_ARGUMENT)) {
155                 return_ACPI_STATUS(AE_OK);
156         }
157
158         /* Make sure that we only delete this subtree */
159
160         if (op->common.parent) {
161                 prev = op->common.parent->common.value.arg;
162                 if (!prev) {
163
164                         /* Nothing more to do */
165
166                         goto cleanup;
167                 }
168
169                 /*
170                  * Check if we need to replace the operator and its subtree
171                  * with a return value op (placeholder op)
172                  */
173                 parent_info =
174                     acpi_ps_get_opcode_info(op->common.parent->common.
175                                             aml_opcode);
176
177                 switch (parent_info->class) {
178                 case AML_CLASS_CONTROL:
179                         break;
180
181                 case AML_CLASS_CREATE:
182
183                         /*
184                          * These opcodes contain term_arg operands. The current
185                          * op must be replaced by a placeholder return op
186                          */
187                         replacement_op =
188                             acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP);
189                         if (!replacement_op) {
190                                 status = AE_NO_MEMORY;
191                         }
192                         break;
193
194                 case AML_CLASS_NAMED_OBJECT:
195
196                         /*
197                          * These opcodes contain term_arg operands. The current
198                          * op must be replaced by a placeholder return op
199                          */
200                         if ((op->common.parent->common.aml_opcode ==
201                              AML_REGION_OP)
202                             || (op->common.parent->common.aml_opcode ==
203                                 AML_DATA_REGION_OP)
204                             || (op->common.parent->common.aml_opcode ==
205                                 AML_BUFFER_OP)
206                             || (op->common.parent->common.aml_opcode ==
207                                 AML_PACKAGE_OP)
208                             || (op->common.parent->common.aml_opcode ==
209                                 AML_BANK_FIELD_OP)
210                             || (op->common.parent->common.aml_opcode ==
211                                 AML_VAR_PACKAGE_OP)) {
212                                 replacement_op =
213                                     acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP);
214                                 if (!replacement_op) {
215                                         status = AE_NO_MEMORY;
216                                 }
217                         } else
218                             if ((op->common.parent->common.aml_opcode ==
219                                  AML_NAME_OP)
220                                 && (walk_state->pass_number <=
221                                     ACPI_IMODE_LOAD_PASS2)) {
222                                 if ((op->common.aml_opcode == AML_BUFFER_OP)
223                                     || (op->common.aml_opcode == AML_PACKAGE_OP)
224                                     || (op->common.aml_opcode ==
225                                         AML_VAR_PACKAGE_OP)) {
226                                         replacement_op =
227                                             acpi_ps_alloc_op(op->common.
228                                                              aml_opcode);
229                                         if (!replacement_op) {
230                                                 status = AE_NO_MEMORY;
231                                         } else {
232                                                 replacement_op->named.data =
233                                                     op->named.data;
234                                                 replacement_op->named.length =
235                                                     op->named.length;
236                                         }
237                                 }
238                         }
239                         break;
240
241                 default:
242
243                         replacement_op =
244                             acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP);
245                         if (!replacement_op) {
246                                 status = AE_NO_MEMORY;
247                         }
248                 }
249
250                 /* We must unlink this op from the parent tree */
251
252                 if (prev == op) {
253
254                         /* This op is the first in the list */
255
256                         if (replacement_op) {
257                                 replacement_op->common.parent =
258                                     op->common.parent;
259                                 replacement_op->common.value.arg = NULL;
260                                 replacement_op->common.node = op->common.node;
261                                 op->common.parent->common.value.arg =
262                                     replacement_op;
263                                 replacement_op->common.next = op->common.next;
264                         } else {
265                                 op->common.parent->common.value.arg =
266                                     op->common.next;
267                         }
268                 }
269
270                 /* Search the parent list */
271
272                 else
273                         while (prev) {
274
275                                 /* Traverse all siblings in the parent's argument list */
276
277                                 next = prev->common.next;
278                                 if (next == op) {
279                                         if (replacement_op) {
280                                                 replacement_op->common.parent =
281                                                     op->common.parent;
282                                                 replacement_op->common.value.
283                                                     arg = NULL;
284                                                 replacement_op->common.node =
285                                                     op->common.node;
286                                                 prev->common.next =
287                                                     replacement_op;
288                                                 replacement_op->common.next =
289                                                     op->common.next;
290                                                 next = NULL;
291                                         } else {
292                                                 prev->common.next =
293                                                     op->common.next;
294                                                 next = NULL;
295                                         }
296                                 }
297                                 prev = next;
298                         }
299         }
300
301       cleanup:
302
303         /* Now we can actually delete the subtree rooted at Op */
304
305         acpi_ps_delete_parse_tree(op);
306         return_ACPI_STATUS(status);
307 }
308
309 /*******************************************************************************
310  *
311  * FUNCTION:    acpi_ps_next_parse_state
312  *
313  * PARAMETERS:  walk_state          - Current state
314  *              Op                  - Current parse op
315  *              callback_status     - Status from previous operation
316  *
317  * RETURN:      Status
318  *
319  * DESCRIPTION: Update the parser state based upon the return exception from
320  *              the parser callback.
321  *
322  ******************************************************************************/
323
324 acpi_status
325 acpi_ps_next_parse_state(struct acpi_walk_state *walk_state,
326                          union acpi_parse_object *op,
327                          acpi_status callback_status)
328 {
329         struct acpi_parse_state *parser_state = &walk_state->parser_state;
330         acpi_status status = AE_CTRL_PENDING;
331
332         ACPI_FUNCTION_TRACE_PTR(ps_next_parse_state, op);
333
334         switch (callback_status) {
335         case AE_CTRL_TERMINATE:
336                 /*
337                  * A control method was terminated via a RETURN statement.
338                  * The walk of this method is complete.
339                  */
340                 parser_state->aml = parser_state->aml_end;
341                 status = AE_CTRL_TERMINATE;
342                 break;
343
344         case AE_CTRL_BREAK:
345
346                 parser_state->aml = walk_state->aml_last_while;
347                 walk_state->control_state->common.value = FALSE;
348                 status = AE_CTRL_BREAK;
349                 break;
350
351         case AE_CTRL_CONTINUE:
352
353                 parser_state->aml = walk_state->aml_last_while;
354                 status = AE_CTRL_CONTINUE;
355                 break;
356
357         case AE_CTRL_PENDING:
358
359                 parser_state->aml = walk_state->aml_last_while;
360                 break;
361
362 #if 0
363         case AE_CTRL_SKIP:
364
365                 parser_state->aml = parser_state->scope->parse_scope.pkg_end;
366                 status = AE_OK;
367                 break;
368 #endif
369
370         case AE_CTRL_TRUE:
371                 /*
372                  * Predicate of an IF was true, and we are at the matching ELSE.
373                  * Just close out this package
374                  */
375                 parser_state->aml = acpi_ps_get_next_package_end(parser_state);
376                 status = AE_CTRL_PENDING;
377                 break;
378
379         case AE_CTRL_FALSE:
380                 /*
381                  * Either an IF/WHILE Predicate was false or we encountered a BREAK
382                  * opcode.  In both cases, we do not execute the rest of the
383                  * package;  We simply close out the parent (finishing the walk of
384                  * this branch of the tree) and continue execution at the parent
385                  * level.
386                  */
387                 parser_state->aml = parser_state->scope->parse_scope.pkg_end;
388
389                 /* In the case of a BREAK, just force a predicate (if any) to FALSE */
390
391                 walk_state->control_state->common.value = FALSE;
392                 status = AE_CTRL_END;
393                 break;
394
395         case AE_CTRL_TRANSFER:
396
397                 /* A method call (invocation) -- transfer control */
398
399                 status = AE_CTRL_TRANSFER;
400                 walk_state->prev_op = op;
401                 walk_state->method_call_op = op;
402                 walk_state->method_call_node =
403                     (op->common.value.arg)->common.node;
404
405                 /* Will return value (if any) be used by the caller? */
406
407                 walk_state->return_used =
408                     acpi_ds_is_result_used(op, walk_state);
409                 break;
410
411         default:
412
413                 status = callback_status;
414                 if ((callback_status & AE_CODE_MASK) == AE_CODE_CONTROL) {
415                         status = AE_OK;
416                 }
417                 break;
418         }
419
420         return_ACPI_STATUS(status);
421 }
422
423 /*******************************************************************************
424  *
425  * FUNCTION:    acpi_ps_parse_aml
426  *
427  * PARAMETERS:  walk_state      - Current state
428  *
429  *
430  * RETURN:      Status
431  *
432  * DESCRIPTION: Parse raw AML and return a tree of ops
433  *
434  ******************************************************************************/
435
436 acpi_status acpi_ps_parse_aml(struct acpi_walk_state *walk_state)
437 {
438         acpi_status status;
439         struct acpi_thread_state *thread;
440         struct acpi_thread_state *prev_walk_list = acpi_gbl_current_walk_list;
441         struct acpi_walk_state *previous_walk_state;
442
443         ACPI_FUNCTION_TRACE(ps_parse_aml);
444
445         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
446                           "Entered with WalkState=%p Aml=%p size=%X\n",
447                           walk_state, walk_state->parser_state.aml,
448                           walk_state->parser_state.aml_size));
449
450         if (!walk_state->parser_state.aml) {
451                 return_ACPI_STATUS(AE_NULL_OBJECT);
452         }
453
454         /* Create and initialize a new thread state */
455
456         thread = acpi_ut_create_thread_state();
457         if (!thread) {
458                 if (walk_state->method_desc) {
459
460                         /* Executing a control method - additional cleanup */
461
462                         acpi_ds_terminate_control_method(
463                                 walk_state->method_desc, walk_state);
464                 }
465
466                 acpi_ds_delete_walk_state(walk_state);
467                 return_ACPI_STATUS(AE_NO_MEMORY);
468         }
469
470         walk_state->thread = thread;
471
472         /*
473          * If executing a method, the starting sync_level is this method's
474          * sync_level
475          */
476         if (walk_state->method_desc) {
477                 walk_state->thread->current_sync_level =
478                     walk_state->method_desc->method.sync_level;
479         }
480
481         acpi_ds_push_walk_state(walk_state, thread);
482
483         /*
484          * This global allows the AML debugger to get a handle to the currently
485          * executing control method.
486          */
487         acpi_gbl_current_walk_list = thread;
488
489         /*
490          * Execute the walk loop as long as there is a valid Walk State.  This
491          * handles nested control method invocations without recursion.
492          */
493         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "State=%p\n", walk_state));
494
495         status = AE_OK;
496         while (walk_state) {
497                 if (ACPI_SUCCESS(status)) {
498                         /*
499                          * The parse_loop executes AML until the method terminates
500                          * or calls another method.
501                          */
502                         status = acpi_ps_parse_loop(walk_state);
503                 }
504
505                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
506                                   "Completed one call to walk loop, %s State=%p\n",
507                                   acpi_format_exception(status), walk_state));
508
509                 if (status == AE_CTRL_TRANSFER) {
510                         /*
511                          * A method call was detected.
512                          * Transfer control to the called control method
513                          */
514                         status =
515                             acpi_ds_call_control_method(thread, walk_state,
516                                                         NULL);
517                         if (ACPI_FAILURE(status)) {
518                                 status =
519                                     acpi_ds_method_error(status, walk_state);
520                         }
521
522                         /*
523                          * If the transfer to the new method method call worked, a new walk
524                          * state was created -- get it
525                          */
526                         walk_state = acpi_ds_get_current_walk_state(thread);
527                         continue;
528                 } else if (status == AE_CTRL_TERMINATE) {
529                         status = AE_OK;
530                 } else if ((status != AE_OK) && (walk_state->method_desc)) {
531
532                         /* Either the method parse or actual execution failed */
533
534                         ACPI_ERROR_METHOD("Method parse/execution failed",
535                                           walk_state->method_node, NULL,
536                                           status);
537
538                         /* Check for possible multi-thread reentrancy problem */
539
540                         if ((status == AE_ALREADY_EXISTS) &&
541                             (!(walk_state->method_desc->method.
542                                info_flags & ACPI_METHOD_SERIALIZED))) {
543                                 /*
544                                  * Method is not serialized and tried to create an object
545                                  * twice. The probable cause is that the method cannot
546                                  * handle reentrancy. Mark as "pending serialized" now, and
547                                  * then mark "serialized" when the last thread exits.
548                                  */
549                                 walk_state->method_desc->method.info_flags |=
550                                     ACPI_METHOD_SERIALIZED_PENDING;
551                         }
552                 }
553
554                 /* We are done with this walk, move on to the parent if any */
555
556                 walk_state = acpi_ds_pop_walk_state(thread);
557
558                 /* Reset the current scope to the beginning of scope stack */
559
560                 acpi_ds_scope_stack_clear(walk_state);
561
562                 /*
563                  * If we just returned from the execution of a control method or if we
564                  * encountered an error during the method parse phase, there's lots of
565                  * cleanup to do
566                  */
567                 if (((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) ==
568                      ACPI_PARSE_EXECUTE) || (ACPI_FAILURE(status))) {
569                         acpi_ds_terminate_control_method(walk_state->
570                                                          method_desc,
571                                                          walk_state);
572                 }
573
574                 /* Delete this walk state and all linked control states */
575
576                 acpi_ps_cleanup_scope(&walk_state->parser_state);
577                 previous_walk_state = walk_state;
578
579                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
580                                   "ReturnValue=%p, ImplicitValue=%p State=%p\n",
581                                   walk_state->return_desc,
582                                   walk_state->implicit_return_obj, walk_state));
583
584                 /* Check if we have restarted a preempted walk */
585
586                 walk_state = acpi_ds_get_current_walk_state(thread);
587                 if (walk_state) {
588                         if (ACPI_SUCCESS(status)) {
589                                 /*
590                                  * There is another walk state, restart it.
591                                  * If the method return value is not used by the parent,
592                                  * The object is deleted
593                                  */
594                                 if (!previous_walk_state->return_desc) {
595                                         /*
596                                          * In slack mode execution, if there is no return value
597                                          * we should implicitly return zero (0) as a default value.
598                                          */
599                                         if (acpi_gbl_enable_interpreter_slack &&
600                                             !previous_walk_state->
601                                             implicit_return_obj) {
602                                                 previous_walk_state->
603                                                     implicit_return_obj =
604                                                     acpi_ut_create_integer_object
605                                                     ((u64) 0);
606                                                 if (!previous_walk_state->
607                                                     implicit_return_obj) {
608                                                         return_ACPI_STATUS
609                                                             (AE_NO_MEMORY);
610                                                 }
611                                         }
612
613                                         /* Restart the calling control method */
614
615                                         status =
616                                             acpi_ds_restart_control_method
617                                             (walk_state,
618                                              previous_walk_state->
619                                              implicit_return_obj);
620                                 } else {
621                                         /*
622                                          * We have a valid return value, delete any implicit
623                                          * return value.
624                                          */
625                                         acpi_ds_clear_implicit_return
626                                             (previous_walk_state);
627
628                                         status =
629                                             acpi_ds_restart_control_method
630                                             (walk_state,
631                                              previous_walk_state->return_desc);
632                                 }
633                                 if (ACPI_SUCCESS(status)) {
634                                         walk_state->walk_type |=
635                                             ACPI_WALK_METHOD_RESTART;
636                                 }
637                         } else {
638                                 /* On error, delete any return object or implicit return */
639
640                                 acpi_ut_remove_reference(previous_walk_state->
641                                                          return_desc);
642                                 acpi_ds_clear_implicit_return
643                                     (previous_walk_state);
644                         }
645                 }
646
647                 /*
648                  * Just completed a 1st-level method, save the final internal return
649                  * value (if any)
650                  */
651                 else if (previous_walk_state->caller_return_desc) {
652                         if (previous_walk_state->implicit_return_obj) {
653                                 *(previous_walk_state->caller_return_desc) =
654                                     previous_walk_state->implicit_return_obj;
655                         } else {
656                                 /* NULL if no return value */
657
658                                 *(previous_walk_state->caller_return_desc) =
659                                     previous_walk_state->return_desc;
660                         }
661                 } else {
662                         if (previous_walk_state->return_desc) {
663
664                                 /* Caller doesn't want it, must delete it */
665
666                                 acpi_ut_remove_reference(previous_walk_state->
667                                                          return_desc);
668                         }
669                         if (previous_walk_state->implicit_return_obj) {
670
671                                 /* Caller doesn't want it, must delete it */
672
673                                 acpi_ut_remove_reference(previous_walk_state->
674                                                          implicit_return_obj);
675                         }
676                 }
677
678                 acpi_ds_delete_walk_state(previous_walk_state);
679         }
680
681         /* Normal exit */
682
683         acpi_ex_release_all_mutexes(thread);
684         acpi_ut_delete_generic_state(ACPI_CAST_PTR
685                                      (union acpi_generic_state, thread));
686         acpi_gbl_current_walk_list = prev_walk_list;
687         return_ACPI_STATUS(status);
688 }