Revert "ARM: tegra: tegratab: dummy change"
[linux-2.6.git] / drivers / acpi / acpica / dsutils.c
1 /*******************************************************************************
2  *
3  * Module Name: dsutils - Dispatcher utilities
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 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acparser.h"
47 #include "amlcode.h"
48 #include "acdispat.h"
49 #include "acinterp.h"
50 #include "acnamesp.h"
51 #include "acdebug.h"
52
53 #define _COMPONENT          ACPI_DISPATCHER
54 ACPI_MODULE_NAME("dsutils")
55
56 /*******************************************************************************
57  *
58  * FUNCTION:    acpi_ds_clear_implicit_return
59  *
60  * PARAMETERS:  walk_state          - Current State
61  *
62  * RETURN:      None.
63  *
64  * DESCRIPTION: Clear and remove a reference on an implicit return value.  Used
65  *              to delete "stale" return values (if enabled, the return value
66  *              from every operator is saved at least momentarily, in case the
67  *              parent method exits.)
68  *
69  ******************************************************************************/
70 void acpi_ds_clear_implicit_return(struct acpi_walk_state *walk_state)
71 {
72         ACPI_FUNCTION_NAME(ds_clear_implicit_return);
73
74         /*
75          * Slack must be enabled for this feature
76          */
77         if (!acpi_gbl_enable_interpreter_slack) {
78                 return;
79         }
80
81         if (walk_state->implicit_return_obj) {
82                 /*
83                  * Delete any "stale" implicit return. However, in
84                  * complex statements, the implicit return value can be
85                  * bubbled up several levels.
86                  */
87                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
88                                   "Removing reference on stale implicit return obj %p\n",
89                                   walk_state->implicit_return_obj));
90
91                 acpi_ut_remove_reference(walk_state->implicit_return_obj);
92                 walk_state->implicit_return_obj = NULL;
93         }
94 }
95
96 #ifndef ACPI_NO_METHOD_EXECUTION
97 /*******************************************************************************
98  *
99  * FUNCTION:    acpi_ds_do_implicit_return
100  *
101  * PARAMETERS:  return_desc         - The return value
102  *              walk_state          - Current State
103  *              add_reference       - True if a reference should be added to the
104  *                                    return object
105  *
106  * RETURN:      TRUE if implicit return enabled, FALSE otherwise
107  *
108  * DESCRIPTION: Implements the optional "implicit return".  We save the result
109  *              of every ASL operator and control method invocation in case the
110  *              parent method exit.  Before storing a new return value, we
111  *              delete the previous return value.
112  *
113  ******************************************************************************/
114
115 u8
116 acpi_ds_do_implicit_return(union acpi_operand_object *return_desc,
117                            struct acpi_walk_state *walk_state, u8 add_reference)
118 {
119         ACPI_FUNCTION_NAME(ds_do_implicit_return);
120
121         /*
122          * Slack must be enabled for this feature, and we must
123          * have a valid return object
124          */
125         if ((!acpi_gbl_enable_interpreter_slack) || (!return_desc)) {
126                 return (FALSE);
127         }
128
129         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
130                           "Result %p will be implicitly returned; Prev=%p\n",
131                           return_desc, walk_state->implicit_return_obj));
132
133         /*
134          * Delete any "stale" implicit return value first. However, in
135          * complex statements, the implicit return value can be
136          * bubbled up several levels, so we don't clear the value if it
137          * is the same as the return_desc.
138          */
139         if (walk_state->implicit_return_obj) {
140                 if (walk_state->implicit_return_obj == return_desc) {
141                         return (TRUE);
142                 }
143                 acpi_ds_clear_implicit_return(walk_state);
144         }
145
146         /* Save the implicit return value, add a reference if requested */
147
148         walk_state->implicit_return_obj = return_desc;
149         if (add_reference) {
150                 acpi_ut_add_reference(return_desc);
151         }
152
153         return (TRUE);
154 }
155
156 /*******************************************************************************
157  *
158  * FUNCTION:    acpi_ds_is_result_used
159  *
160  * PARAMETERS:  Op                  - Current Op
161  *              walk_state          - Current State
162  *
163  * RETURN:      TRUE if result is used, FALSE otherwise
164  *
165  * DESCRIPTION: Check if a result object will be used by the parent
166  *
167  ******************************************************************************/
168
169 u8
170 acpi_ds_is_result_used(union acpi_parse_object * op,
171                        struct acpi_walk_state * walk_state)
172 {
173         const struct acpi_opcode_info *parent_info;
174
175         ACPI_FUNCTION_TRACE_PTR(ds_is_result_used, op);
176
177         /* Must have both an Op and a Result Object */
178
179         if (!op) {
180                 ACPI_ERROR((AE_INFO, "Null Op"));
181                 return_UINT8(TRUE);
182         }
183
184         /*
185          * We know that this operator is not a
186          * Return() operator (would not come here.) The following code is the
187          * optional support for a so-called "implicit return". Some AML code
188          * assumes that the last value of the method is "implicitly" returned
189          * to the caller. Just save the last result as the return value.
190          * NOTE: this is optional because the ASL language does not actually
191          * support this behavior.
192          */
193         (void)acpi_ds_do_implicit_return(walk_state->result_obj, walk_state,
194                                          TRUE);
195
196         /*
197          * Now determine if the parent will use the result
198          *
199          * If there is no parent, or the parent is a scope_op, we are executing
200          * at the method level. An executing method typically has no parent,
201          * since each method is parsed separately.  A method invoked externally
202          * via execute_control_method has a scope_op as the parent.
203          */
204         if ((!op->common.parent) ||
205             (op->common.parent->common.aml_opcode == AML_SCOPE_OP)) {
206
207                 /* No parent, the return value cannot possibly be used */
208
209                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
210                                   "At Method level, result of [%s] not used\n",
211                                   acpi_ps_get_opcode_name(op->common.
212                                                           aml_opcode)));
213                 return_UINT8(FALSE);
214         }
215
216         /* Get info on the parent. The root_op is AML_SCOPE */
217
218         parent_info =
219             acpi_ps_get_opcode_info(op->common.parent->common.aml_opcode);
220         if (parent_info->class == AML_CLASS_UNKNOWN) {
221                 ACPI_ERROR((AE_INFO, "Unknown parent opcode Op=%p", op));
222                 return_UINT8(FALSE);
223         }
224
225         /*
226          * Decide what to do with the result based on the parent.  If
227          * the parent opcode will not use the result, delete the object.
228          * Otherwise leave it as is, it will be deleted when it is used
229          * as an operand later.
230          */
231         switch (parent_info->class) {
232         case AML_CLASS_CONTROL:
233
234                 switch (op->common.parent->common.aml_opcode) {
235                 case AML_RETURN_OP:
236
237                         /* Never delete the return value associated with a return opcode */
238
239                         goto result_used;
240
241                 case AML_IF_OP:
242                 case AML_WHILE_OP:
243
244                         /*
245                          * If we are executing the predicate AND this is the predicate op,
246                          * we will use the return value
247                          */
248                         if ((walk_state->control_state->common.state ==
249                              ACPI_CONTROL_PREDICATE_EXECUTING)
250                             && (walk_state->control_state->control.
251                                 predicate_op == op)) {
252                                 goto result_used;
253                         }
254                         break;
255
256                 default:
257                         /* Ignore other control opcodes */
258                         break;
259                 }
260
261                 /* The general control opcode returns no result */
262
263                 goto result_not_used;
264
265         case AML_CLASS_CREATE:
266
267                 /*
268                  * These opcodes allow term_arg(s) as operands and therefore
269                  * the operands can be method calls.  The result is used.
270                  */
271                 goto result_used;
272
273         case AML_CLASS_NAMED_OBJECT:
274
275                 if ((op->common.parent->common.aml_opcode == AML_REGION_OP) ||
276                     (op->common.parent->common.aml_opcode == AML_DATA_REGION_OP)
277                     || (op->common.parent->common.aml_opcode == AML_PACKAGE_OP)
278                     || (op->common.parent->common.aml_opcode ==
279                         AML_VAR_PACKAGE_OP)
280                     || (op->common.parent->common.aml_opcode == AML_BUFFER_OP)
281                     || (op->common.parent->common.aml_opcode ==
282                         AML_INT_EVAL_SUBTREE_OP)
283                     || (op->common.parent->common.aml_opcode ==
284                         AML_BANK_FIELD_OP)) {
285                         /*
286                          * These opcodes allow term_arg(s) as operands and therefore
287                          * the operands can be method calls.  The result is used.
288                          */
289                         goto result_used;
290                 }
291
292                 goto result_not_used;
293
294         default:
295
296                 /*
297                  * In all other cases. the parent will actually use the return
298                  * object, so keep it.
299                  */
300                 goto result_used;
301         }
302
303       result_used:
304         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
305                           "Result of [%s] used by Parent [%s] Op=%p\n",
306                           acpi_ps_get_opcode_name(op->common.aml_opcode),
307                           acpi_ps_get_opcode_name(op->common.parent->common.
308                                                   aml_opcode), op));
309
310         return_UINT8(TRUE);
311
312       result_not_used:
313         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
314                           "Result of [%s] not used by Parent [%s] Op=%p\n",
315                           acpi_ps_get_opcode_name(op->common.aml_opcode),
316                           acpi_ps_get_opcode_name(op->common.parent->common.
317                                                   aml_opcode), op));
318
319         return_UINT8(FALSE);
320 }
321
322 /*******************************************************************************
323  *
324  * FUNCTION:    acpi_ds_delete_result_if_not_used
325  *
326  * PARAMETERS:  Op              - Current parse Op
327  *              result_obj      - Result of the operation
328  *              walk_state      - Current state
329  *
330  * RETURN:      Status
331  *
332  * DESCRIPTION: Used after interpretation of an opcode.  If there is an internal
333  *              result descriptor, check if the parent opcode will actually use
334  *              this result.  If not, delete the result now so that it will
335  *              not become orphaned.
336  *
337  ******************************************************************************/
338
339 void
340 acpi_ds_delete_result_if_not_used(union acpi_parse_object *op,
341                                   union acpi_operand_object *result_obj,
342                                   struct acpi_walk_state *walk_state)
343 {
344         union acpi_operand_object *obj_desc;
345         acpi_status status;
346
347         ACPI_FUNCTION_TRACE_PTR(ds_delete_result_if_not_used, result_obj);
348
349         if (!op) {
350                 ACPI_ERROR((AE_INFO, "Null Op"));
351                 return_VOID;
352         }
353
354         if (!result_obj) {
355                 return_VOID;
356         }
357
358         if (!acpi_ds_is_result_used(op, walk_state)) {
359
360                 /* Must pop the result stack (obj_desc should be equal to result_obj) */
361
362                 status = acpi_ds_result_pop(&obj_desc, walk_state);
363                 if (ACPI_SUCCESS(status)) {
364                         acpi_ut_remove_reference(result_obj);
365                 }
366         }
367
368         return_VOID;
369 }
370
371 /*******************************************************************************
372  *
373  * FUNCTION:    acpi_ds_resolve_operands
374  *
375  * PARAMETERS:  walk_state          - Current walk state with operands on stack
376  *
377  * RETURN:      Status
378  *
379  * DESCRIPTION: Resolve all operands to their values.  Used to prepare
380  *              arguments to a control method invocation (a call from one
381  *              method to another.)
382  *
383  ******************************************************************************/
384
385 acpi_status acpi_ds_resolve_operands(struct acpi_walk_state *walk_state)
386 {
387         u32 i;
388         acpi_status status = AE_OK;
389
390         ACPI_FUNCTION_TRACE_PTR(ds_resolve_operands, walk_state);
391
392         /*
393          * Attempt to resolve each of the valid operands
394          * Method arguments are passed by reference, not by value.  This means
395          * that the actual objects are passed, not copies of the objects.
396          */
397         for (i = 0; i < walk_state->num_operands; i++) {
398                 status =
399                     acpi_ex_resolve_to_value(&walk_state->operands[i],
400                                              walk_state);
401                 if (ACPI_FAILURE(status)) {
402                         break;
403                 }
404         }
405
406         return_ACPI_STATUS(status);
407 }
408
409 /*******************************************************************************
410  *
411  * FUNCTION:    acpi_ds_clear_operands
412  *
413  * PARAMETERS:  walk_state          - Current walk state with operands on stack
414  *
415  * RETURN:      None
416  *
417  * DESCRIPTION: Clear all operands on the current walk state operand stack.
418  *
419  ******************************************************************************/
420
421 void acpi_ds_clear_operands(struct acpi_walk_state *walk_state)
422 {
423         u32 i;
424
425         ACPI_FUNCTION_TRACE_PTR(ds_clear_operands, walk_state);
426
427         /* Remove a reference on each operand on the stack */
428
429         for (i = 0; i < walk_state->num_operands; i++) {
430                 /*
431                  * Remove a reference to all operands, including both
432                  * "Arguments" and "Targets".
433                  */
434                 acpi_ut_remove_reference(walk_state->operands[i]);
435                 walk_state->operands[i] = NULL;
436         }
437
438         walk_state->num_operands = 0;
439         return_VOID;
440 }
441 #endif
442
443 /*******************************************************************************
444  *
445  * FUNCTION:    acpi_ds_create_operand
446  *
447  * PARAMETERS:  walk_state      - Current walk state
448  *              Arg             - Parse object for the argument
449  *              arg_index       - Which argument (zero based)
450  *
451  * RETURN:      Status
452  *
453  * DESCRIPTION: Translate a parse tree object that is an argument to an AML
454  *              opcode to the equivalent interpreter object.  This may include
455  *              looking up a name or entering a new name into the internal
456  *              namespace.
457  *
458  ******************************************************************************/
459
460 acpi_status
461 acpi_ds_create_operand(struct acpi_walk_state *walk_state,
462                        union acpi_parse_object *arg, u32 arg_index)
463 {
464         acpi_status status = AE_OK;
465         char *name_string;
466         u32 name_length;
467         union acpi_operand_object *obj_desc;
468         union acpi_parse_object *parent_op;
469         u16 opcode;
470         acpi_interpreter_mode interpreter_mode;
471         const struct acpi_opcode_info *op_info;
472
473         ACPI_FUNCTION_TRACE_PTR(ds_create_operand, arg);
474
475         /* A valid name must be looked up in the namespace */
476
477         if ((arg->common.aml_opcode == AML_INT_NAMEPATH_OP) &&
478             (arg->common.value.string) &&
479             !(arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
480                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Getting a name: Arg=%p\n",
481                                   arg));
482
483                 /* Get the entire name string from the AML stream */
484
485                 status =
486                     acpi_ex_get_name_string(ACPI_TYPE_ANY,
487                                             arg->common.value.buffer,
488                                             &name_string, &name_length);
489
490                 if (ACPI_FAILURE(status)) {
491                         return_ACPI_STATUS(status);
492                 }
493
494                 /* All prefixes have been handled, and the name is in name_string */
495
496                 /*
497                  * Special handling for buffer_field declarations. This is a deferred
498                  * opcode that unfortunately defines the field name as the last
499                  * parameter instead of the first.  We get here when we are performing
500                  * the deferred execution, so the actual name of the field is already
501                  * in the namespace.  We don't want to attempt to look it up again
502                  * because we may be executing in a different scope than where the
503                  * actual opcode exists.
504                  */
505                 if ((walk_state->deferred_node) &&
506                     (walk_state->deferred_node->type == ACPI_TYPE_BUFFER_FIELD)
507                     && (arg_index ==
508                         (u32) ((walk_state->opcode ==
509                                 AML_CREATE_FIELD_OP) ? 3 : 2))) {
510                         obj_desc =
511                             ACPI_CAST_PTR(union acpi_operand_object,
512                                           walk_state->deferred_node);
513                         status = AE_OK;
514                 } else {        /* All other opcodes */
515
516                         /*
517                          * Differentiate between a namespace "create" operation
518                          * versus a "lookup" operation (IMODE_LOAD_PASS2 vs.
519                          * IMODE_EXECUTE) in order to support the creation of
520                          * namespace objects during the execution of control methods.
521                          */
522                         parent_op = arg->common.parent;
523                         op_info =
524                             acpi_ps_get_opcode_info(parent_op->common.
525                                                     aml_opcode);
526                         if ((op_info->flags & AML_NSNODE)
527                             && (parent_op->common.aml_opcode !=
528                                 AML_INT_METHODCALL_OP)
529                             && (parent_op->common.aml_opcode != AML_REGION_OP)
530                             && (parent_op->common.aml_opcode !=
531                                 AML_INT_NAMEPATH_OP)) {
532
533                                 /* Enter name into namespace if not found */
534
535                                 interpreter_mode = ACPI_IMODE_LOAD_PASS2;
536                         } else {
537                                 /* Return a failure if name not found */
538
539                                 interpreter_mode = ACPI_IMODE_EXECUTE;
540                         }
541
542                         status =
543                             acpi_ns_lookup(walk_state->scope_info, name_string,
544                                            ACPI_TYPE_ANY, interpreter_mode,
545                                            ACPI_NS_SEARCH_PARENT |
546                                            ACPI_NS_DONT_OPEN_SCOPE, walk_state,
547                                            ACPI_CAST_INDIRECT_PTR(struct
548                                                                   acpi_namespace_node,
549                                                                   &obj_desc));
550                         /*
551                          * The only case where we pass through (ignore) a NOT_FOUND
552                          * error is for the cond_ref_of opcode.
553                          */
554                         if (status == AE_NOT_FOUND) {
555                                 if (parent_op->common.aml_opcode ==
556                                     AML_COND_REF_OF_OP) {
557                                         /*
558                                          * For the Conditional Reference op, it's OK if
559                                          * the name is not found;  We just need a way to
560                                          * indicate this to the interpreter, set the
561                                          * object to the root
562                                          */
563                                         obj_desc = ACPI_CAST_PTR(union
564                                                                  acpi_operand_object,
565                                                                  acpi_gbl_root_node);
566                                         status = AE_OK;
567                                 } else {
568                                         /*
569                                          * We just plain didn't find it -- which is a
570                                          * very serious error at this point
571                                          */
572                                         status = AE_AML_NAME_NOT_FOUND;
573                                 }
574                         }
575
576                         if (ACPI_FAILURE(status)) {
577                                 ACPI_ERROR_NAMESPACE(name_string, status);
578                         }
579                 }
580
581                 /* Free the namestring created above */
582
583                 ACPI_FREE(name_string);
584
585                 /* Check status from the lookup */
586
587                 if (ACPI_FAILURE(status)) {
588                         return_ACPI_STATUS(status);
589                 }
590
591                 /* Put the resulting object onto the current object stack */
592
593                 status = acpi_ds_obj_stack_push(obj_desc, walk_state);
594                 if (ACPI_FAILURE(status)) {
595                         return_ACPI_STATUS(status);
596                 }
597                 ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
598                                    (obj_desc, walk_state));
599         } else {
600                 /* Check for null name case */
601
602                 if ((arg->common.aml_opcode == AML_INT_NAMEPATH_OP) &&
603                     !(arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
604                         /*
605                          * If the name is null, this means that this is an
606                          * optional result parameter that was not specified
607                          * in the original ASL.  Create a Zero Constant for a
608                          * placeholder.  (Store to a constant is a Noop.)
609                          */
610                         opcode = AML_ZERO_OP;   /* Has no arguments! */
611
612                         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
613                                           "Null namepath: Arg=%p\n", arg));
614                 } else {
615                         opcode = arg->common.aml_opcode;
616                 }
617
618                 /* Get the object type of the argument */
619
620                 op_info = acpi_ps_get_opcode_info(opcode);
621                 if (op_info->object_type == ACPI_TYPE_INVALID) {
622                         return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
623                 }
624
625                 if ((op_info->flags & AML_HAS_RETVAL)
626                     || (arg->common.flags & ACPI_PARSEOP_IN_STACK)) {
627                         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
628                                           "Argument previously created, already stacked\n"));
629
630                         ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
631                                            (walk_state->
632                                             operands[walk_state->num_operands -
633                                                      1], walk_state));
634
635                         /*
636                          * Use value that was already previously returned
637                          * by the evaluation of this argument
638                          */
639                         status = acpi_ds_result_pop(&obj_desc, walk_state);
640                         if (ACPI_FAILURE(status)) {
641                                 /*
642                                  * Only error is underflow, and this indicates
643                                  * a missing or null operand!
644                                  */
645                                 ACPI_EXCEPTION((AE_INFO, status,
646                                                 "Missing or null operand"));
647                                 return_ACPI_STATUS(status);
648                         }
649                 } else {
650                         /* Create an ACPI_INTERNAL_OBJECT for the argument */
651
652                         obj_desc =
653                             acpi_ut_create_internal_object(op_info->
654                                                            object_type);
655                         if (!obj_desc) {
656                                 return_ACPI_STATUS(AE_NO_MEMORY);
657                         }
658
659                         /* Initialize the new object */
660
661                         status =
662                             acpi_ds_init_object_from_op(walk_state, arg, opcode,
663                                                         &obj_desc);
664                         if (ACPI_FAILURE(status)) {
665                                 acpi_ut_delete_object_desc(obj_desc);
666                                 return_ACPI_STATUS(status);
667                         }
668                 }
669
670                 /* Put the operand object on the object stack */
671
672                 status = acpi_ds_obj_stack_push(obj_desc, walk_state);
673                 if (ACPI_FAILURE(status)) {
674                         return_ACPI_STATUS(status);
675                 }
676
677                 ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
678                                    (obj_desc, walk_state));
679         }
680
681         return_ACPI_STATUS(AE_OK);
682 }
683
684 /*******************************************************************************
685  *
686  * FUNCTION:    acpi_ds_create_operands
687  *
688  * PARAMETERS:  walk_state          - Current state
689  *              first_arg           - First argument of a parser argument tree
690  *
691  * RETURN:      Status
692  *
693  * DESCRIPTION: Convert an operator's arguments from a parse tree format to
694  *              namespace objects and place those argument object on the object
695  *              stack in preparation for evaluation by the interpreter.
696  *
697  ******************************************************************************/
698
699 acpi_status
700 acpi_ds_create_operands(struct acpi_walk_state *walk_state,
701                         union acpi_parse_object *first_arg)
702 {
703         acpi_status status = AE_OK;
704         union acpi_parse_object *arg;
705         union acpi_parse_object *arguments[ACPI_OBJ_NUM_OPERANDS];
706         u32 arg_count = 0;
707         u32 index = walk_state->num_operands;
708         u32 i;
709
710         ACPI_FUNCTION_TRACE_PTR(ds_create_operands, first_arg);
711
712         /* Get all arguments in the list */
713
714         arg = first_arg;
715         while (arg) {
716                 if (index >= ACPI_OBJ_NUM_OPERANDS) {
717                         return_ACPI_STATUS(AE_BAD_DATA);
718                 }
719
720                 arguments[index] = arg;
721                 walk_state->operands[index] = NULL;
722
723                 /* Move on to next argument, if any */
724
725                 arg = arg->common.next;
726                 arg_count++;
727                 index++;
728         }
729
730         index--;
731
732         /* It is the appropriate order to get objects from the Result stack */
733
734         for (i = 0; i < arg_count; i++) {
735                 arg = arguments[index];
736
737                 /* Force the filling of the operand stack in inverse order */
738
739                 walk_state->operand_index = (u8) index;
740
741                 status = acpi_ds_create_operand(walk_state, arg, index);
742                 if (ACPI_FAILURE(status)) {
743                         goto cleanup;
744                 }
745
746                 index--;
747
748                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
749                                   "Arg #%u (%p) done, Arg1=%p\n", index, arg,
750                                   first_arg));
751         }
752
753         return_ACPI_STATUS(status);
754
755       cleanup:
756         /*
757          * We must undo everything done above; meaning that we must
758          * pop everything off of the operand stack and delete those
759          * objects
760          */
761         acpi_ds_obj_stack_pop_and_delete(arg_count, walk_state);
762
763         ACPI_EXCEPTION((AE_INFO, status, "While creating Arg %u", index));
764         return_ACPI_STATUS(status);
765 }
766
767 /*****************************************************************************
768  *
769  * FUNCTION:    acpi_ds_evaluate_name_path
770  *
771  * PARAMETERS:  walk_state      - Current state of the parse tree walk,
772  *                                the opcode of current operation should be
773  *                                AML_INT_NAMEPATH_OP
774  *
775  * RETURN:      Status
776  *
777  * DESCRIPTION: Translate the -name_path- parse tree object to the equivalent
778  *              interpreter object, convert it to value, if needed, duplicate
779  *              it, if needed, and push it onto the current result stack.
780  *
781  ****************************************************************************/
782
783 acpi_status acpi_ds_evaluate_name_path(struct acpi_walk_state *walk_state)
784 {
785         acpi_status status = AE_OK;
786         union acpi_parse_object *op = walk_state->op;
787         union acpi_operand_object **operand = &walk_state->operands[0];
788         union acpi_operand_object *new_obj_desc;
789         u8 type;
790
791         ACPI_FUNCTION_TRACE_PTR(ds_evaluate_name_path, walk_state);
792
793         if (!op->common.parent) {
794
795                 /* This happens after certain exception processing */
796
797                 goto exit;
798         }
799
800         if ((op->common.parent->common.aml_opcode == AML_PACKAGE_OP) ||
801             (op->common.parent->common.aml_opcode == AML_VAR_PACKAGE_OP) ||
802             (op->common.parent->common.aml_opcode == AML_REF_OF_OP)) {
803
804                 /* TBD: Should we specify this feature as a bit of op_info->Flags of these opcodes? */
805
806                 goto exit;
807         }
808
809         status = acpi_ds_create_operand(walk_state, op, 0);
810         if (ACPI_FAILURE(status)) {
811                 goto exit;
812         }
813
814         if (op->common.flags & ACPI_PARSEOP_TARGET) {
815                 new_obj_desc = *operand;
816                 goto push_result;
817         }
818
819         type = (*operand)->common.type;
820
821         status = acpi_ex_resolve_to_value(operand, walk_state);
822         if (ACPI_FAILURE(status)) {
823                 goto exit;
824         }
825
826         if (type == ACPI_TYPE_INTEGER) {
827
828                 /* It was incremented by acpi_ex_resolve_to_value */
829
830                 acpi_ut_remove_reference(*operand);
831
832                 status =
833                     acpi_ut_copy_iobject_to_iobject(*operand, &new_obj_desc,
834                                                     walk_state);
835                 if (ACPI_FAILURE(status)) {
836                         goto exit;
837                 }
838         } else {
839                 /*
840                  * The object either was anew created or is
841                  * a Namespace node - don't decrement it.
842                  */
843                 new_obj_desc = *operand;
844         }
845
846         /* Cleanup for name-path operand */
847
848         status = acpi_ds_obj_stack_pop(1, walk_state);
849         if (ACPI_FAILURE(status)) {
850                 walk_state->result_obj = new_obj_desc;
851                 goto exit;
852         }
853
854       push_result:
855
856         walk_state->result_obj = new_obj_desc;
857
858         status = acpi_ds_result_push(walk_state->result_obj, walk_state);
859         if (ACPI_SUCCESS(status)) {
860
861                 /* Force to take it from stack */
862
863                 op->common.flags |= ACPI_PARSEOP_IN_STACK;
864         }
865
866       exit:
867
868         return_ACPI_STATUS(status);
869 }