Merge branch 'master' of /home/shaggy/git/linus-clean/
[linux-2.6] / drivers / acpi / acpica / dsopcode.c
1 /******************************************************************************
2  *
3  * Module Name: dsopcode - Dispatcher Op Region support and handling of
4  *                         "control" opcodes
5  *
6  *****************************************************************************/
7
8 /*
9  * Copyright (C) 2000 - 2008, Intel Corp.
10  * All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions, and the following disclaimer,
17  *    without modification.
18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19  *    substantially similar to the "NO WARRANTY" disclaimer below
20  *    ("Disclaimer") and any redistribution must be conditioned upon
21  *    including a substantially similar Disclaimer requirement for further
22  *    binary redistribution.
23  * 3. Neither the names of the above-listed copyright holders nor the names
24  *    of any contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * Alternatively, this software may be distributed under the terms of the
28  * GNU General Public License ("GPL") version 2 as published by the Free
29  * Software Foundation.
30  *
31  * NO WARRANTY
32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42  * POSSIBILITY OF SUCH DAMAGES.
43  */
44
45 #include <acpi/acpi.h>
46 #include "accommon.h"
47 #include "acparser.h"
48 #include "amlcode.h"
49 #include "acdispat.h"
50 #include "acinterp.h"
51 #include "acnamesp.h"
52 #include "acevents.h"
53 #include "actables.h"
54
55 #define _COMPONENT          ACPI_DISPATCHER
56 ACPI_MODULE_NAME("dsopcode")
57
58 /* Local prototypes */
59 static acpi_status
60 acpi_ds_execute_arguments(struct acpi_namespace_node *node,
61                           struct acpi_namespace_node *scope_node,
62                           u32 aml_length, u8 * aml_start);
63
64 static acpi_status
65 acpi_ds_init_buffer_field(u16 aml_opcode,
66                           union acpi_operand_object *obj_desc,
67                           union acpi_operand_object *buffer_desc,
68                           union acpi_operand_object *offset_desc,
69                           union acpi_operand_object *length_desc,
70                           union acpi_operand_object *result_desc);
71
72 /*******************************************************************************
73  *
74  * FUNCTION:    acpi_ds_execute_arguments
75  *
76  * PARAMETERS:  Node                - Object NS node
77  *              scope_node          - Parent NS node
78  *              aml_length          - Length of executable AML
79  *              aml_start           - Pointer to the AML
80  *
81  * RETURN:      Status.
82  *
83  * DESCRIPTION: Late (deferred) execution of region or field arguments
84  *
85  ******************************************************************************/
86
87 static acpi_status
88 acpi_ds_execute_arguments(struct acpi_namespace_node *node,
89                           struct acpi_namespace_node *scope_node,
90                           u32 aml_length, u8 * aml_start)
91 {
92         acpi_status status;
93         union acpi_parse_object *op;
94         struct acpi_walk_state *walk_state;
95
96         ACPI_FUNCTION_TRACE(ds_execute_arguments);
97
98         /*
99          * Allocate a new parser op to be the root of the parsed tree
100          */
101         op = acpi_ps_alloc_op(AML_INT_EVAL_SUBTREE_OP);
102         if (!op) {
103                 return_ACPI_STATUS(AE_NO_MEMORY);
104         }
105
106         /* Save the Node for use in acpi_ps_parse_aml */
107
108         op->common.node = scope_node;
109
110         /* Create and initialize a new parser state */
111
112         walk_state = acpi_ds_create_walk_state(0, NULL, NULL, NULL);
113         if (!walk_state) {
114                 status = AE_NO_MEMORY;
115                 goto cleanup;
116         }
117
118         status = acpi_ds_init_aml_walk(walk_state, op, NULL, aml_start,
119                                        aml_length, NULL, ACPI_IMODE_LOAD_PASS1);
120         if (ACPI_FAILURE(status)) {
121                 acpi_ds_delete_walk_state(walk_state);
122                 goto cleanup;
123         }
124
125         /* Mark this parse as a deferred opcode */
126
127         walk_state->parse_flags = ACPI_PARSE_DEFERRED_OP;
128         walk_state->deferred_node = node;
129
130         /* Pass1: Parse the entire declaration */
131
132         status = acpi_ps_parse_aml(walk_state);
133         if (ACPI_FAILURE(status)) {
134                 goto cleanup;
135         }
136
137         /* Get and init the Op created above */
138
139         op->common.node = node;
140         acpi_ps_delete_parse_tree(op);
141
142         /* Evaluate the deferred arguments */
143
144         op = acpi_ps_alloc_op(AML_INT_EVAL_SUBTREE_OP);
145         if (!op) {
146                 return_ACPI_STATUS(AE_NO_MEMORY);
147         }
148
149         op->common.node = scope_node;
150
151         /* Create and initialize a new parser state */
152
153         walk_state = acpi_ds_create_walk_state(0, NULL, NULL, NULL);
154         if (!walk_state) {
155                 status = AE_NO_MEMORY;
156                 goto cleanup;
157         }
158
159         /* Execute the opcode and arguments */
160
161         status = acpi_ds_init_aml_walk(walk_state, op, NULL, aml_start,
162                                        aml_length, NULL, ACPI_IMODE_EXECUTE);
163         if (ACPI_FAILURE(status)) {
164                 acpi_ds_delete_walk_state(walk_state);
165                 goto cleanup;
166         }
167
168         /* Mark this execution as a deferred opcode */
169
170         walk_state->deferred_node = node;
171         status = acpi_ps_parse_aml(walk_state);
172
173       cleanup:
174         acpi_ps_delete_parse_tree(op);
175         return_ACPI_STATUS(status);
176 }
177
178 /*******************************************************************************
179  *
180  * FUNCTION:    acpi_ds_get_buffer_field_arguments
181  *
182  * PARAMETERS:  obj_desc        - A valid buffer_field object
183  *
184  * RETURN:      Status.
185  *
186  * DESCRIPTION: Get buffer_field Buffer and Index. This implements the late
187  *              evaluation of these field attributes.
188  *
189  ******************************************************************************/
190
191 acpi_status
192 acpi_ds_get_buffer_field_arguments(union acpi_operand_object *obj_desc)
193 {
194         union acpi_operand_object *extra_desc;
195         struct acpi_namespace_node *node;
196         acpi_status status;
197
198         ACPI_FUNCTION_TRACE_PTR(ds_get_buffer_field_arguments, obj_desc);
199
200         if (obj_desc->common.flags & AOPOBJ_DATA_VALID) {
201                 return_ACPI_STATUS(AE_OK);
202         }
203
204         /* Get the AML pointer (method object) and buffer_field node */
205
206         extra_desc = acpi_ns_get_secondary_object(obj_desc);
207         node = obj_desc->buffer_field.node;
208
209         ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
210                         (ACPI_TYPE_BUFFER_FIELD, node, NULL));
211         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "[%4.4s] BufferField Arg Init\n",
212                           acpi_ut_get_node_name(node)));
213
214         /* Execute the AML code for the term_arg arguments */
215
216         status = acpi_ds_execute_arguments(node, acpi_ns_get_parent_node(node),
217                                            extra_desc->extra.aml_length,
218                                            extra_desc->extra.aml_start);
219         return_ACPI_STATUS(status);
220 }
221
222 /*******************************************************************************
223  *
224  * FUNCTION:    acpi_ds_get_bank_field_arguments
225  *
226  * PARAMETERS:  obj_desc        - A valid bank_field object
227  *
228  * RETURN:      Status.
229  *
230  * DESCRIPTION: Get bank_field bank_value. This implements the late
231  *              evaluation of these field attributes.
232  *
233  ******************************************************************************/
234
235 acpi_status
236 acpi_ds_get_bank_field_arguments(union acpi_operand_object *obj_desc)
237 {
238         union acpi_operand_object *extra_desc;
239         struct acpi_namespace_node *node;
240         acpi_status status;
241
242         ACPI_FUNCTION_TRACE_PTR(ds_get_bank_field_arguments, obj_desc);
243
244         if (obj_desc->common.flags & AOPOBJ_DATA_VALID) {
245                 return_ACPI_STATUS(AE_OK);
246         }
247
248         /* Get the AML pointer (method object) and bank_field node */
249
250         extra_desc = acpi_ns_get_secondary_object(obj_desc);
251         node = obj_desc->bank_field.node;
252
253         ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
254                         (ACPI_TYPE_LOCAL_BANK_FIELD, node, NULL));
255         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "[%4.4s] BankField Arg Init\n",
256                           acpi_ut_get_node_name(node)));
257
258         /* Execute the AML code for the term_arg arguments */
259
260         status = acpi_ds_execute_arguments(node, acpi_ns_get_parent_node(node),
261                                            extra_desc->extra.aml_length,
262                                            extra_desc->extra.aml_start);
263         return_ACPI_STATUS(status);
264 }
265
266 /*******************************************************************************
267  *
268  * FUNCTION:    acpi_ds_get_buffer_arguments
269  *
270  * PARAMETERS:  obj_desc        - A valid Buffer object
271  *
272  * RETURN:      Status.
273  *
274  * DESCRIPTION: Get Buffer length and initializer byte list.  This implements
275  *              the late evaluation of these attributes.
276  *
277  ******************************************************************************/
278
279 acpi_status acpi_ds_get_buffer_arguments(union acpi_operand_object *obj_desc)
280 {
281         struct acpi_namespace_node *node;
282         acpi_status status;
283
284         ACPI_FUNCTION_TRACE_PTR(ds_get_buffer_arguments, obj_desc);
285
286         if (obj_desc->common.flags & AOPOBJ_DATA_VALID) {
287                 return_ACPI_STATUS(AE_OK);
288         }
289
290         /* Get the Buffer node */
291
292         node = obj_desc->buffer.node;
293         if (!node) {
294                 ACPI_ERROR((AE_INFO,
295                             "No pointer back to NS node in buffer obj %p",
296                             obj_desc));
297                 return_ACPI_STATUS(AE_AML_INTERNAL);
298         }
299
300         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Buffer Arg Init\n"));
301
302         /* Execute the AML code for the term_arg arguments */
303
304         status = acpi_ds_execute_arguments(node, node,
305                                            obj_desc->buffer.aml_length,
306                                            obj_desc->buffer.aml_start);
307         return_ACPI_STATUS(status);
308 }
309
310 /*******************************************************************************
311  *
312  * FUNCTION:    acpi_ds_get_package_arguments
313  *
314  * PARAMETERS:  obj_desc        - A valid Package object
315  *
316  * RETURN:      Status.
317  *
318  * DESCRIPTION: Get Package length and initializer byte list.  This implements
319  *              the late evaluation of these attributes.
320  *
321  ******************************************************************************/
322
323 acpi_status acpi_ds_get_package_arguments(union acpi_operand_object *obj_desc)
324 {
325         struct acpi_namespace_node *node;
326         acpi_status status;
327
328         ACPI_FUNCTION_TRACE_PTR(ds_get_package_arguments, obj_desc);
329
330         if (obj_desc->common.flags & AOPOBJ_DATA_VALID) {
331                 return_ACPI_STATUS(AE_OK);
332         }
333
334         /* Get the Package node */
335
336         node = obj_desc->package.node;
337         if (!node) {
338                 ACPI_ERROR((AE_INFO,
339                             "No pointer back to NS node in package %p",
340                             obj_desc));
341                 return_ACPI_STATUS(AE_AML_INTERNAL);
342         }
343
344         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Package Arg Init\n"));
345
346         /* Execute the AML code for the term_arg arguments */
347
348         status = acpi_ds_execute_arguments(node, node,
349                                            obj_desc->package.aml_length,
350                                            obj_desc->package.aml_start);
351         return_ACPI_STATUS(status);
352 }
353
354 /*****************************************************************************
355  *
356  * FUNCTION:    acpi_ds_get_region_arguments
357  *
358  * PARAMETERS:  obj_desc        - A valid region object
359  *
360  * RETURN:      Status.
361  *
362  * DESCRIPTION: Get region address and length.  This implements the late
363  *              evaluation of these region attributes.
364  *
365  ****************************************************************************/
366
367 acpi_status acpi_ds_get_region_arguments(union acpi_operand_object *obj_desc)
368 {
369         struct acpi_namespace_node *node;
370         acpi_status status;
371         union acpi_operand_object *extra_desc;
372
373         ACPI_FUNCTION_TRACE_PTR(ds_get_region_arguments, obj_desc);
374
375         if (obj_desc->region.flags & AOPOBJ_DATA_VALID) {
376                 return_ACPI_STATUS(AE_OK);
377         }
378
379         extra_desc = acpi_ns_get_secondary_object(obj_desc);
380         if (!extra_desc) {
381                 return_ACPI_STATUS(AE_NOT_EXIST);
382         }
383
384         /* Get the Region node */
385
386         node = obj_desc->region.node;
387
388         ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
389                         (ACPI_TYPE_REGION, node, NULL));
390
391         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "[%4.4s] OpRegion Arg Init at AML %p\n",
392                           acpi_ut_get_node_name(node),
393                           extra_desc->extra.aml_start));
394
395         /* Execute the argument AML */
396
397         status = acpi_ds_execute_arguments(node, acpi_ns_get_parent_node(node),
398                                            extra_desc->extra.aml_length,
399                                            extra_desc->extra.aml_start);
400         if (ACPI_FAILURE(status)) {
401                 return_ACPI_STATUS(status);
402         }
403
404         /* Validate the region address/length via the host OS */
405
406         status = acpi_os_validate_address(obj_desc->region.space_id,
407                                           obj_desc->region.address,
408                                           (acpi_size) obj_desc->region.length,
409                                           acpi_ut_get_node_name(node));
410
411         if (ACPI_FAILURE(status)) {
412                 /*
413                  * Invalid address/length. We will emit an error message and mark
414                  * the region as invalid, so that it will cause an additional error if
415                  * it is ever used. Then return AE_OK.
416                  */
417                 ACPI_EXCEPTION((AE_INFO, status,
418                                 "During address validation of OpRegion [%4.4s]",
419                                 node->name.ascii));
420                 obj_desc->common.flags |= AOPOBJ_INVALID;
421                 status = AE_OK;
422         }
423
424         return_ACPI_STATUS(status);
425 }
426
427 /*******************************************************************************
428  *
429  * FUNCTION:    acpi_ds_initialize_region
430  *
431  * PARAMETERS:  obj_handle      - Region namespace node
432  *
433  * RETURN:      Status
434  *
435  * DESCRIPTION: Front end to ev_initialize_region
436  *
437  ******************************************************************************/
438
439 acpi_status acpi_ds_initialize_region(acpi_handle obj_handle)
440 {
441         union acpi_operand_object *obj_desc;
442         acpi_status status;
443
444         obj_desc = acpi_ns_get_attached_object(obj_handle);
445
446         /* Namespace is NOT locked */
447
448         status = acpi_ev_initialize_region(obj_desc, FALSE);
449         return (status);
450 }
451
452 /*******************************************************************************
453  *
454  * FUNCTION:    acpi_ds_init_buffer_field
455  *
456  * PARAMETERS:  aml_opcode      - create_xxx_field
457  *              obj_desc        - buffer_field object
458  *              buffer_desc     - Host Buffer
459  *              offset_desc     - Offset into buffer
460  *              length_desc     - Length of field (CREATE_FIELD_OP only)
461  *              result_desc     - Where to store the result
462  *
463  * RETURN:      Status
464  *
465  * DESCRIPTION: Perform actual initialization of a buffer field
466  *
467  ******************************************************************************/
468
469 static acpi_status
470 acpi_ds_init_buffer_field(u16 aml_opcode,
471                           union acpi_operand_object *obj_desc,
472                           union acpi_operand_object *buffer_desc,
473                           union acpi_operand_object *offset_desc,
474                           union acpi_operand_object *length_desc,
475                           union acpi_operand_object *result_desc)
476 {
477         u32 offset;
478         u32 bit_offset;
479         u32 bit_count;
480         u8 field_flags;
481         acpi_status status;
482
483         ACPI_FUNCTION_TRACE_PTR(ds_init_buffer_field, obj_desc);
484
485         /* Host object must be a Buffer */
486
487         if (ACPI_GET_OBJECT_TYPE(buffer_desc) != ACPI_TYPE_BUFFER) {
488                 ACPI_ERROR((AE_INFO,
489                             "Target of Create Field is not a Buffer object - %s",
490                             acpi_ut_get_object_type_name(buffer_desc)));
491
492                 status = AE_AML_OPERAND_TYPE;
493                 goto cleanup;
494         }
495
496         /*
497          * The last parameter to all of these opcodes (result_desc) started
498          * out as a name_string, and should therefore now be a NS node
499          * after resolution in acpi_ex_resolve_operands().
500          */
501         if (ACPI_GET_DESCRIPTOR_TYPE(result_desc) != ACPI_DESC_TYPE_NAMED) {
502                 ACPI_ERROR((AE_INFO,
503                             "(%s) destination not a NS Node [%s]",
504                             acpi_ps_get_opcode_name(aml_opcode),
505                             acpi_ut_get_descriptor_name(result_desc)));
506
507                 status = AE_AML_OPERAND_TYPE;
508                 goto cleanup;
509         }
510
511         offset = (u32) offset_desc->integer.value;
512
513         /*
514          * Setup the Bit offsets and counts, according to the opcode
515          */
516         switch (aml_opcode) {
517         case AML_CREATE_FIELD_OP:
518
519                 /* Offset is in bits, count is in bits */
520
521                 field_flags = AML_FIELD_ACCESS_BYTE;
522                 bit_offset = offset;
523                 bit_count = (u32) length_desc->integer.value;
524
525                 /* Must have a valid (>0) bit count */
526
527                 if (bit_count == 0) {
528                         ACPI_ERROR((AE_INFO,
529                                     "Attempt to CreateField of length zero"));
530                         status = AE_AML_OPERAND_VALUE;
531                         goto cleanup;
532                 }
533                 break;
534
535         case AML_CREATE_BIT_FIELD_OP:
536
537                 /* Offset is in bits, Field is one bit */
538
539                 bit_offset = offset;
540                 bit_count = 1;
541                 field_flags = AML_FIELD_ACCESS_BYTE;
542                 break;
543
544         case AML_CREATE_BYTE_FIELD_OP:
545
546                 /* Offset is in bytes, field is one byte */
547
548                 bit_offset = 8 * offset;
549                 bit_count = 8;
550                 field_flags = AML_FIELD_ACCESS_BYTE;
551                 break;
552
553         case AML_CREATE_WORD_FIELD_OP:
554
555                 /* Offset is in bytes, field is one word */
556
557                 bit_offset = 8 * offset;
558                 bit_count = 16;
559                 field_flags = AML_FIELD_ACCESS_WORD;
560                 break;
561
562         case AML_CREATE_DWORD_FIELD_OP:
563
564                 /* Offset is in bytes, field is one dword */
565
566                 bit_offset = 8 * offset;
567                 bit_count = 32;
568                 field_flags = AML_FIELD_ACCESS_DWORD;
569                 break;
570
571         case AML_CREATE_QWORD_FIELD_OP:
572
573                 /* Offset is in bytes, field is one qword */
574
575                 bit_offset = 8 * offset;
576                 bit_count = 64;
577                 field_flags = AML_FIELD_ACCESS_QWORD;
578                 break;
579
580         default:
581
582                 ACPI_ERROR((AE_INFO,
583                             "Unknown field creation opcode %02x", aml_opcode));
584                 status = AE_AML_BAD_OPCODE;
585                 goto cleanup;
586         }
587
588         /* Entire field must fit within the current length of the buffer */
589
590         if ((bit_offset + bit_count) > (8 * (u32) buffer_desc->buffer.length)) {
591                 ACPI_ERROR((AE_INFO,
592                             "Field [%4.4s] at %d exceeds Buffer [%4.4s] size %d (bits)",
593                             acpi_ut_get_node_name(result_desc),
594                             bit_offset + bit_count,
595                             acpi_ut_get_node_name(buffer_desc->buffer.node),
596                             8 * (u32) buffer_desc->buffer.length));
597                 status = AE_AML_BUFFER_LIMIT;
598                 goto cleanup;
599         }
600
601         /*
602          * Initialize areas of the field object that are common to all fields
603          * For field_flags, use LOCK_RULE = 0 (NO_LOCK),
604          * UPDATE_RULE = 0 (UPDATE_PRESERVE)
605          */
606         status = acpi_ex_prep_common_field_object(obj_desc, field_flags, 0,
607                                                   bit_offset, bit_count);
608         if (ACPI_FAILURE(status)) {
609                 goto cleanup;
610         }
611
612         obj_desc->buffer_field.buffer_obj = buffer_desc;
613
614         /* Reference count for buffer_desc inherits obj_desc count */
615
616         buffer_desc->common.reference_count = (u16)
617             (buffer_desc->common.reference_count +
618              obj_desc->common.reference_count);
619
620       cleanup:
621
622         /* Always delete the operands */
623
624         acpi_ut_remove_reference(offset_desc);
625         acpi_ut_remove_reference(buffer_desc);
626
627         if (aml_opcode == AML_CREATE_FIELD_OP) {
628                 acpi_ut_remove_reference(length_desc);
629         }
630
631         /* On failure, delete the result descriptor */
632
633         if (ACPI_FAILURE(status)) {
634                 acpi_ut_remove_reference(result_desc);  /* Result descriptor */
635         } else {
636                 /* Now the address and length are valid for this buffer_field */
637
638                 obj_desc->buffer_field.flags |= AOPOBJ_DATA_VALID;
639         }
640
641         return_ACPI_STATUS(status);
642 }
643
644 /*******************************************************************************
645  *
646  * FUNCTION:    acpi_ds_eval_buffer_field_operands
647  *
648  * PARAMETERS:  walk_state      - Current walk
649  *              Op              - A valid buffer_field Op object
650  *
651  * RETURN:      Status
652  *
653  * DESCRIPTION: Get buffer_field Buffer and Index
654  *              Called from acpi_ds_exec_end_op during buffer_field parse tree walk
655  *
656  ******************************************************************************/
657
658 acpi_status
659 acpi_ds_eval_buffer_field_operands(struct acpi_walk_state *walk_state,
660                                    union acpi_parse_object *op)
661 {
662         acpi_status status;
663         union acpi_operand_object *obj_desc;
664         struct acpi_namespace_node *node;
665         union acpi_parse_object *next_op;
666
667         ACPI_FUNCTION_TRACE_PTR(ds_eval_buffer_field_operands, op);
668
669         /*
670          * This is where we evaluate the address and length fields of the
671          * create_xxx_field declaration
672          */
673         node = op->common.node;
674
675         /* next_op points to the op that holds the Buffer */
676
677         next_op = op->common.value.arg;
678
679         /* Evaluate/create the address and length operands */
680
681         status = acpi_ds_create_operands(walk_state, next_op);
682         if (ACPI_FAILURE(status)) {
683                 return_ACPI_STATUS(status);
684         }
685
686         obj_desc = acpi_ns_get_attached_object(node);
687         if (!obj_desc) {
688                 return_ACPI_STATUS(AE_NOT_EXIST);
689         }
690
691         /* Resolve the operands */
692
693         status = acpi_ex_resolve_operands(op->common.aml_opcode,
694                                           ACPI_WALK_OPERANDS, walk_state);
695         if (ACPI_FAILURE(status)) {
696                 ACPI_ERROR((AE_INFO, "(%s) bad operand(s) (%X)",
697                             acpi_ps_get_opcode_name(op->common.aml_opcode),
698                             status));
699
700                 return_ACPI_STATUS(status);
701         }
702
703         /* Initialize the Buffer Field */
704
705         if (op->common.aml_opcode == AML_CREATE_FIELD_OP) {
706
707                 /* NOTE: Slightly different operands for this opcode */
708
709                 status =
710                     acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
711                                               walk_state->operands[0],
712                                               walk_state->operands[1],
713                                               walk_state->operands[2],
714                                               walk_state->operands[3]);
715         } else {
716                 /* All other, create_xxx_field opcodes */
717
718                 status =
719                     acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
720                                               walk_state->operands[0],
721                                               walk_state->operands[1], NULL,
722                                               walk_state->operands[2]);
723         }
724
725         return_ACPI_STATUS(status);
726 }
727
728 /*******************************************************************************
729  *
730  * FUNCTION:    acpi_ds_eval_region_operands
731  *
732  * PARAMETERS:  walk_state      - Current walk
733  *              Op              - A valid region Op object
734  *
735  * RETURN:      Status
736  *
737  * DESCRIPTION: Get region address and length
738  *              Called from acpi_ds_exec_end_op during op_region parse tree walk
739  *
740  ******************************************************************************/
741
742 acpi_status
743 acpi_ds_eval_region_operands(struct acpi_walk_state *walk_state,
744                              union acpi_parse_object *op)
745 {
746         acpi_status status;
747         union acpi_operand_object *obj_desc;
748         union acpi_operand_object *operand_desc;
749         struct acpi_namespace_node *node;
750         union acpi_parse_object *next_op;
751
752         ACPI_FUNCTION_TRACE_PTR(ds_eval_region_operands, op);
753
754         /*
755          * This is where we evaluate the address and length fields of the
756          * op_region declaration
757          */
758         node = op->common.node;
759
760         /* next_op points to the op that holds the space_iD */
761
762         next_op = op->common.value.arg;
763
764         /* next_op points to address op */
765
766         next_op = next_op->common.next;
767
768         /* Evaluate/create the address and length operands */
769
770         status = acpi_ds_create_operands(walk_state, next_op);
771         if (ACPI_FAILURE(status)) {
772                 return_ACPI_STATUS(status);
773         }
774
775         /* Resolve the length and address operands to numbers */
776
777         status = acpi_ex_resolve_operands(op->common.aml_opcode,
778                                           ACPI_WALK_OPERANDS, walk_state);
779         if (ACPI_FAILURE(status)) {
780                 return_ACPI_STATUS(status);
781         }
782
783         obj_desc = acpi_ns_get_attached_object(node);
784         if (!obj_desc) {
785                 return_ACPI_STATUS(AE_NOT_EXIST);
786         }
787
788         /*
789          * Get the length operand and save it
790          * (at Top of stack)
791          */
792         operand_desc = walk_state->operands[walk_state->num_operands - 1];
793
794         obj_desc->region.length = (u32) operand_desc->integer.value;
795         acpi_ut_remove_reference(operand_desc);
796
797         /*
798          * Get the address and save it
799          * (at top of stack - 1)
800          */
801         operand_desc = walk_state->operands[walk_state->num_operands - 2];
802
803         obj_desc->region.address = (acpi_physical_address)
804             operand_desc->integer.value;
805         acpi_ut_remove_reference(operand_desc);
806
807         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
808                           obj_desc,
809                           ACPI_FORMAT_NATIVE_UINT(obj_desc->region.address),
810                           obj_desc->region.length));
811
812         /* Now the address and length are valid for this opregion */
813
814         obj_desc->region.flags |= AOPOBJ_DATA_VALID;
815
816         return_ACPI_STATUS(status);
817 }
818
819 /*******************************************************************************
820  *
821  * FUNCTION:    acpi_ds_eval_table_region_operands
822  *
823  * PARAMETERS:  walk_state      - Current walk
824  *              Op              - A valid region Op object
825  *
826  * RETURN:      Status
827  *
828  * DESCRIPTION: Get region address and length
829  *              Called from acpi_ds_exec_end_op during data_table_region parse tree walk
830  *
831  ******************************************************************************/
832
833 acpi_status
834 acpi_ds_eval_table_region_operands(struct acpi_walk_state *walk_state,
835                                    union acpi_parse_object *op)
836 {
837         acpi_status status;
838         union acpi_operand_object *obj_desc;
839         union acpi_operand_object **operand;
840         struct acpi_namespace_node *node;
841         union acpi_parse_object *next_op;
842         u32 table_index;
843         struct acpi_table_header *table;
844
845         ACPI_FUNCTION_TRACE_PTR(ds_eval_table_region_operands, op);
846
847         /*
848          * This is where we evaluate the signature_string and oem_iDString
849          * and oem_table_iDString of the data_table_region declaration
850          */
851         node = op->common.node;
852
853         /* next_op points to signature_string op */
854
855         next_op = op->common.value.arg;
856
857         /*
858          * Evaluate/create the signature_string and oem_iDString
859          * and oem_table_iDString operands
860          */
861         status = acpi_ds_create_operands(walk_state, next_op);
862         if (ACPI_FAILURE(status)) {
863                 return_ACPI_STATUS(status);
864         }
865
866         /*
867          * Resolve the signature_string and oem_iDString
868          * and oem_table_iDString operands
869          */
870         status = acpi_ex_resolve_operands(op->common.aml_opcode,
871                                           ACPI_WALK_OPERANDS, walk_state);
872         if (ACPI_FAILURE(status)) {
873                 return_ACPI_STATUS(status);
874         }
875
876         operand = &walk_state->operands[0];
877
878         /* Find the ACPI table */
879
880         status = acpi_tb_find_table(operand[0]->string.pointer,
881                                     operand[1]->string.pointer,
882                                     operand[2]->string.pointer, &table_index);
883         if (ACPI_FAILURE(status)) {
884                 return_ACPI_STATUS(status);
885         }
886
887         acpi_ut_remove_reference(operand[0]);
888         acpi_ut_remove_reference(operand[1]);
889         acpi_ut_remove_reference(operand[2]);
890
891         status = acpi_get_table_by_index(table_index, &table);
892         if (ACPI_FAILURE(status)) {
893                 return_ACPI_STATUS(status);
894         }
895
896         obj_desc = acpi_ns_get_attached_object(node);
897         if (!obj_desc) {
898                 return_ACPI_STATUS(AE_NOT_EXIST);
899         }
900
901         obj_desc->region.address =
902             (acpi_physical_address) ACPI_TO_INTEGER(table);
903         obj_desc->region.length = table->length;
904
905         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
906                           obj_desc,
907                           ACPI_FORMAT_NATIVE_UINT(obj_desc->region.address),
908                           obj_desc->region.length));
909
910         /* Now the address and length are valid for this opregion */
911
912         obj_desc->region.flags |= AOPOBJ_DATA_VALID;
913
914         return_ACPI_STATUS(status);
915 }
916
917 /*******************************************************************************
918  *
919  * FUNCTION:    acpi_ds_eval_data_object_operands
920  *
921  * PARAMETERS:  walk_state      - Current walk
922  *              Op              - A valid data_object Op object
923  *              obj_desc        - data_object
924  *
925  * RETURN:      Status
926  *
927  * DESCRIPTION: Get the operands and complete the following data object types:
928  *              Buffer, Package.
929  *
930  ******************************************************************************/
931
932 acpi_status
933 acpi_ds_eval_data_object_operands(struct acpi_walk_state *walk_state,
934                                   union acpi_parse_object *op,
935                                   union acpi_operand_object *obj_desc)
936 {
937         acpi_status status;
938         union acpi_operand_object *arg_desc;
939         u32 length;
940
941         ACPI_FUNCTION_TRACE(ds_eval_data_object_operands);
942
943         /* The first operand (for all of these data objects) is the length */
944
945         /*
946          * Set proper index into operand stack for acpi_ds_obj_stack_push
947          * invoked inside acpi_ds_create_operand.
948          */
949         walk_state->operand_index = walk_state->num_operands;
950
951         status = acpi_ds_create_operand(walk_state, op->common.value.arg, 1);
952         if (ACPI_FAILURE(status)) {
953                 return_ACPI_STATUS(status);
954         }
955
956         status = acpi_ex_resolve_operands(walk_state->opcode,
957                                           &(walk_state->
958                                             operands[walk_state->num_operands -
959                                                      1]), walk_state);
960         if (ACPI_FAILURE(status)) {
961                 return_ACPI_STATUS(status);
962         }
963
964         /* Extract length operand */
965
966         arg_desc = walk_state->operands[walk_state->num_operands - 1];
967         length = (u32) arg_desc->integer.value;
968
969         /* Cleanup for length operand */
970
971         status = acpi_ds_obj_stack_pop(1, walk_state);
972         if (ACPI_FAILURE(status)) {
973                 return_ACPI_STATUS(status);
974         }
975
976         acpi_ut_remove_reference(arg_desc);
977
978         /*
979          * Create the actual data object
980          */
981         switch (op->common.aml_opcode) {
982         case AML_BUFFER_OP:
983
984                 status =
985                     acpi_ds_build_internal_buffer_obj(walk_state, op, length,
986                                                       &obj_desc);
987                 break;
988
989         case AML_PACKAGE_OP:
990         case AML_VAR_PACKAGE_OP:
991
992                 status =
993                     acpi_ds_build_internal_package_obj(walk_state, op, length,
994                                                        &obj_desc);
995                 break;
996
997         default:
998                 return_ACPI_STATUS(AE_AML_BAD_OPCODE);
999         }
1000
1001         if (ACPI_SUCCESS(status)) {
1002                 /*
1003                  * Return the object in the walk_state, unless the parent is a package -
1004                  * in this case, the return object will be stored in the parse tree
1005                  * for the package.
1006                  */
1007                 if ((!op->common.parent) ||
1008                     ((op->common.parent->common.aml_opcode != AML_PACKAGE_OP) &&
1009                      (op->common.parent->common.aml_opcode !=
1010                       AML_VAR_PACKAGE_OP)
1011                      && (op->common.parent->common.aml_opcode != AML_NAME_OP))) {
1012                         walk_state->result_obj = obj_desc;
1013                 }
1014         }
1015
1016         return_ACPI_STATUS(status);
1017 }
1018
1019 /*******************************************************************************
1020  *
1021  * FUNCTION:    acpi_ds_eval_bank_field_operands
1022  *
1023  * PARAMETERS:  walk_state      - Current walk
1024  *              Op              - A valid bank_field Op object
1025  *
1026  * RETURN:      Status
1027  *
1028  * DESCRIPTION: Get bank_field bank_value
1029  *              Called from acpi_ds_exec_end_op during bank_field parse tree walk
1030  *
1031  ******************************************************************************/
1032
1033 acpi_status
1034 acpi_ds_eval_bank_field_operands(struct acpi_walk_state *walk_state,
1035                                  union acpi_parse_object *op)
1036 {
1037         acpi_status status;
1038         union acpi_operand_object *obj_desc;
1039         union acpi_operand_object *operand_desc;
1040         struct acpi_namespace_node *node;
1041         union acpi_parse_object *next_op;
1042         union acpi_parse_object *arg;
1043
1044         ACPI_FUNCTION_TRACE_PTR(ds_eval_bank_field_operands, op);
1045
1046         /*
1047          * This is where we evaluate the bank_value field of the
1048          * bank_field declaration
1049          */
1050
1051         /* next_op points to the op that holds the Region */
1052
1053         next_op = op->common.value.arg;
1054
1055         /* next_op points to the op that holds the Bank Register */
1056
1057         next_op = next_op->common.next;
1058
1059         /* next_op points to the op that holds the Bank Value */
1060
1061         next_op = next_op->common.next;
1062
1063         /*
1064          * Set proper index into operand stack for acpi_ds_obj_stack_push
1065          * invoked inside acpi_ds_create_operand.
1066          *
1067          * We use walk_state->Operands[0] to store the evaluated bank_value
1068          */
1069         walk_state->operand_index = 0;
1070
1071         status = acpi_ds_create_operand(walk_state, next_op, 0);
1072         if (ACPI_FAILURE(status)) {
1073                 return_ACPI_STATUS(status);
1074         }
1075
1076         status = acpi_ex_resolve_to_value(&walk_state->operands[0], walk_state);
1077         if (ACPI_FAILURE(status)) {
1078                 return_ACPI_STATUS(status);
1079         }
1080
1081         ACPI_DUMP_OPERANDS(ACPI_WALK_OPERANDS,
1082                            acpi_ps_get_opcode_name(op->common.aml_opcode), 1);
1083         /*
1084          * Get the bank_value operand and save it
1085          * (at Top of stack)
1086          */
1087         operand_desc = walk_state->operands[0];
1088
1089         /* Arg points to the start Bank Field */
1090
1091         arg = acpi_ps_get_arg(op, 4);
1092         while (arg) {
1093
1094                 /* Ignore OFFSET and ACCESSAS terms here */
1095
1096                 if (arg->common.aml_opcode == AML_INT_NAMEDFIELD_OP) {
1097                         node = arg->common.node;
1098
1099                         obj_desc = acpi_ns_get_attached_object(node);
1100                         if (!obj_desc) {
1101                                 return_ACPI_STATUS(AE_NOT_EXIST);
1102                         }
1103
1104                         obj_desc->bank_field.value =
1105                             (u32) operand_desc->integer.value;
1106                 }
1107
1108                 /* Move to next field in the list */
1109
1110                 arg = arg->common.next;
1111         }
1112
1113         acpi_ut_remove_reference(operand_desc);
1114         return_ACPI_STATUS(status);
1115 }
1116
1117 /*******************************************************************************
1118  *
1119  * FUNCTION:    acpi_ds_exec_begin_control_op
1120  *
1121  * PARAMETERS:  walk_list       - The list that owns the walk stack
1122  *              Op              - The control Op
1123  *
1124  * RETURN:      Status
1125  *
1126  * DESCRIPTION: Handles all control ops encountered during control method
1127  *              execution.
1128  *
1129  ******************************************************************************/
1130
1131 acpi_status
1132 acpi_ds_exec_begin_control_op(struct acpi_walk_state *walk_state,
1133                               union acpi_parse_object *op)
1134 {
1135         acpi_status status = AE_OK;
1136         union acpi_generic_state *control_state;
1137
1138         ACPI_FUNCTION_NAME(ds_exec_begin_control_op);
1139
1140         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Op=%p Opcode=%2.2X State=%p\n", op,
1141                           op->common.aml_opcode, walk_state));
1142
1143         switch (op->common.aml_opcode) {
1144         case AML_WHILE_OP:
1145
1146                 /*
1147                  * If this is an additional iteration of a while loop, continue.
1148                  * There is no need to allocate a new control state.
1149                  */
1150                 if (walk_state->control_state) {
1151                         if (walk_state->control_state->control.aml_predicate_start
1152                                 == (walk_state->parser_state.aml - 1)) {
1153
1154                                 /* Reset the state to start-of-loop */
1155
1156                                 walk_state->control_state->common.state =
1157                                     ACPI_CONTROL_CONDITIONAL_EXECUTING;
1158                                 break;
1159                         }
1160                 }
1161
1162                 /*lint -fallthrough */
1163
1164         case AML_IF_OP:
1165
1166                 /*
1167                  * IF/WHILE: Create a new control state to manage these
1168                  * constructs. We need to manage these as a stack, in order
1169                  * to handle nesting.
1170                  */
1171                 control_state = acpi_ut_create_control_state();
1172                 if (!control_state) {
1173                         status = AE_NO_MEMORY;
1174                         break;
1175                 }
1176                 /*
1177                  * Save a pointer to the predicate for multiple executions
1178                  * of a loop
1179                  */
1180                 control_state->control.aml_predicate_start =
1181                     walk_state->parser_state.aml - 1;
1182                 control_state->control.package_end =
1183                     walk_state->parser_state.pkg_end;
1184                 control_state->control.opcode = op->common.aml_opcode;
1185
1186                 /* Push the control state on this walk's control stack */
1187
1188                 acpi_ut_push_generic_state(&walk_state->control_state,
1189                                            control_state);
1190                 break;
1191
1192         case AML_ELSE_OP:
1193
1194                 /* Predicate is in the state object */
1195                 /* If predicate is true, the IF was executed, ignore ELSE part */
1196
1197                 if (walk_state->last_predicate) {
1198                         status = AE_CTRL_TRUE;
1199                 }
1200
1201                 break;
1202
1203         case AML_RETURN_OP:
1204
1205                 break;
1206
1207         default:
1208                 break;
1209         }
1210
1211         return (status);
1212 }
1213
1214 /*******************************************************************************
1215  *
1216  * FUNCTION:    acpi_ds_exec_end_control_op
1217  *
1218  * PARAMETERS:  walk_list       - The list that owns the walk stack
1219  *              Op              - The control Op
1220  *
1221  * RETURN:      Status
1222  *
1223  * DESCRIPTION: Handles all control ops encountered during control method
1224  *              execution.
1225  *
1226  ******************************************************************************/
1227
1228 acpi_status
1229 acpi_ds_exec_end_control_op(struct acpi_walk_state * walk_state,
1230                             union acpi_parse_object * op)
1231 {
1232         acpi_status status = AE_OK;
1233         union acpi_generic_state *control_state;
1234
1235         ACPI_FUNCTION_NAME(ds_exec_end_control_op);
1236
1237         switch (op->common.aml_opcode) {
1238         case AML_IF_OP:
1239
1240                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "[IF_OP] Op=%p\n", op));
1241
1242                 /*
1243                  * Save the result of the predicate in case there is an
1244                  * ELSE to come
1245                  */
1246                 walk_state->last_predicate =
1247                     (u8) walk_state->control_state->common.value;
1248
1249                 /*
1250                  * Pop the control state that was created at the start
1251                  * of the IF and free it
1252                  */
1253                 control_state =
1254                     acpi_ut_pop_generic_state(&walk_state->control_state);
1255                 acpi_ut_delete_generic_state(control_state);
1256                 break;
1257
1258         case AML_ELSE_OP:
1259
1260                 break;
1261
1262         case AML_WHILE_OP:
1263
1264                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "[WHILE_OP] Op=%p\n", op));
1265
1266                 control_state = walk_state->control_state;
1267                 if (control_state->common.value) {
1268
1269                         /* Predicate was true, the body of the loop was just executed */
1270
1271                         /*
1272                          * This loop counter mechanism allows the interpreter to escape
1273                          * possibly infinite loops. This can occur in poorly written AML
1274                          * when the hardware does not respond within a while loop and the
1275                          * loop does not implement a timeout.
1276                          */
1277                         control_state->control.loop_count++;
1278                         if (control_state->control.loop_count >
1279                                 ACPI_MAX_LOOP_ITERATIONS) {
1280                                 status = AE_AML_INFINITE_LOOP;
1281                                 break;
1282                         }
1283
1284                         /*
1285                          * Go back and evaluate the predicate and maybe execute the loop
1286                          * another time
1287                          */
1288                         status = AE_CTRL_PENDING;
1289                         walk_state->aml_last_while =
1290                             control_state->control.aml_predicate_start;
1291                         break;
1292                 }
1293
1294                 /* Predicate was false, terminate this while loop */
1295
1296                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
1297                                   "[WHILE_OP] termination! Op=%p\n", op));
1298
1299                 /* Pop this control state and free it */
1300
1301                 control_state =
1302                     acpi_ut_pop_generic_state(&walk_state->control_state);
1303                 acpi_ut_delete_generic_state(control_state);
1304                 break;
1305
1306         case AML_RETURN_OP:
1307
1308                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
1309                                   "[RETURN_OP] Op=%p Arg=%p\n", op,
1310                                   op->common.value.arg));
1311
1312                 /*
1313                  * One optional operand -- the return value
1314                  * It can be either an immediate operand or a result that
1315                  * has been bubbled up the tree
1316                  */
1317                 if (op->common.value.arg) {
1318
1319                         /* Since we have a real Return(), delete any implicit return */
1320
1321                         acpi_ds_clear_implicit_return(walk_state);
1322
1323                         /* Return statement has an immediate operand */
1324
1325                         status =
1326                             acpi_ds_create_operands(walk_state,
1327                                                     op->common.value.arg);
1328                         if (ACPI_FAILURE(status)) {
1329                                 return (status);
1330                         }
1331
1332                         /*
1333                          * If value being returned is a Reference (such as
1334                          * an arg or local), resolve it now because it may
1335                          * cease to exist at the end of the method.
1336                          */
1337                         status =
1338                             acpi_ex_resolve_to_value(&walk_state->operands[0],
1339                                                      walk_state);
1340                         if (ACPI_FAILURE(status)) {
1341                                 return (status);
1342                         }
1343
1344                         /*
1345                          * Get the return value and save as the last result
1346                          * value.  This is the only place where walk_state->return_desc
1347                          * is set to anything other than zero!
1348                          */
1349                         walk_state->return_desc = walk_state->operands[0];
1350                 } else if (walk_state->result_count) {
1351
1352                         /* Since we have a real Return(), delete any implicit return */
1353
1354                         acpi_ds_clear_implicit_return(walk_state);
1355
1356                         /*
1357                          * The return value has come from a previous calculation.
1358                          *
1359                          * If value being returned is a Reference (such as
1360                          * an arg or local), resolve it now because it may
1361                          * cease to exist at the end of the method.
1362                          *
1363                          * Allow references created by the Index operator to return unchanged.
1364                          */
1365                         if ((ACPI_GET_DESCRIPTOR_TYPE
1366                              (walk_state->results->results.obj_desc[0]) ==
1367                              ACPI_DESC_TYPE_OPERAND)
1368                             &&
1369                             (ACPI_GET_OBJECT_TYPE
1370                              (walk_state->results->results.obj_desc[0]) ==
1371                              ACPI_TYPE_LOCAL_REFERENCE)
1372                             && ((walk_state->results->results.obj_desc[0])->
1373                                 reference.class != ACPI_REFCLASS_INDEX)) {
1374                                 status =
1375                                     acpi_ex_resolve_to_value(&walk_state->
1376                                                              results->results.
1377                                                              obj_desc[0],
1378                                                              walk_state);
1379                                 if (ACPI_FAILURE(status)) {
1380                                         return (status);
1381                                 }
1382                         }
1383
1384                         walk_state->return_desc =
1385                             walk_state->results->results.obj_desc[0];
1386                 } else {
1387                         /* No return operand */
1388
1389                         if (walk_state->num_operands) {
1390                                 acpi_ut_remove_reference(walk_state->
1391                                                          operands[0]);
1392                         }
1393
1394                         walk_state->operands[0] = NULL;
1395                         walk_state->num_operands = 0;
1396                         walk_state->return_desc = NULL;
1397                 }
1398
1399                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
1400                                   "Completed RETURN_OP State=%p, RetVal=%p\n",
1401                                   walk_state, walk_state->return_desc));
1402
1403                 /* End the control method execution right now */
1404
1405                 status = AE_CTRL_TERMINATE;
1406                 break;
1407
1408         case AML_NOOP_OP:
1409
1410                 /* Just do nothing! */
1411                 break;
1412
1413         case AML_BREAK_POINT_OP:
1414
1415                 /* Call up to the OS service layer to handle this */
1416
1417                 status =
1418                     acpi_os_signal(ACPI_SIGNAL_BREAKPOINT,
1419                                    "Executed AML Breakpoint opcode");
1420
1421                 /* If and when it returns, all done. */
1422
1423                 break;
1424
1425         case AML_BREAK_OP:
1426         case AML_CONTINUE_OP:   /* ACPI 2.0 */
1427
1428                 /* Pop and delete control states until we find a while */
1429
1430                 while (walk_state->control_state &&
1431                        (walk_state->control_state->control.opcode !=
1432                         AML_WHILE_OP)) {
1433                         control_state =
1434                             acpi_ut_pop_generic_state(&walk_state->
1435                                                       control_state);
1436                         acpi_ut_delete_generic_state(control_state);
1437                 }
1438
1439                 /* No while found? */
1440
1441                 if (!walk_state->control_state) {
1442                         return (AE_AML_NO_WHILE);
1443                 }
1444
1445                 /* Was: walk_state->aml_last_while = walk_state->control_state->Control.aml_predicate_start; */
1446
1447                 walk_state->aml_last_while =
1448                     walk_state->control_state->control.package_end;
1449
1450                 /* Return status depending on opcode */
1451
1452                 if (op->common.aml_opcode == AML_BREAK_OP) {
1453                         status = AE_CTRL_BREAK;
1454                 } else {
1455                         status = AE_CTRL_CONTINUE;
1456                 }
1457                 break;
1458
1459         default:
1460
1461                 ACPI_ERROR((AE_INFO, "Unknown control opcode=%X Op=%p",
1462                             op->common.aml_opcode, op));
1463
1464                 status = AE_AML_BAD_OPCODE;
1465                 break;
1466         }
1467
1468         return (status);
1469 }