xref: /openbmc/linux/drivers/acpi/acpica/dsopcode.c (revision b6dcefde)
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 (buffer_desc->common.type != 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 			    && ((walk_state->results->results.obj_desc[0])->
1369 				common.type == ACPI_TYPE_LOCAL_REFERENCE)
1370 			    && ((walk_state->results->results.obj_desc[0])->
1371 				reference.class != ACPI_REFCLASS_INDEX)) {
1372 				status =
1373 				    acpi_ex_resolve_to_value(&walk_state->
1374 							     results->results.
1375 							     obj_desc[0],
1376 							     walk_state);
1377 				if (ACPI_FAILURE(status)) {
1378 					return (status);
1379 				}
1380 			}
1381 
1382 			walk_state->return_desc =
1383 			    walk_state->results->results.obj_desc[0];
1384 		} else {
1385 			/* No return operand */
1386 
1387 			if (walk_state->num_operands) {
1388 				acpi_ut_remove_reference(walk_state->
1389 							 operands[0]);
1390 			}
1391 
1392 			walk_state->operands[0] = NULL;
1393 			walk_state->num_operands = 0;
1394 			walk_state->return_desc = NULL;
1395 		}
1396 
1397 		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
1398 				  "Completed RETURN_OP State=%p, RetVal=%p\n",
1399 				  walk_state, walk_state->return_desc));
1400 
1401 		/* End the control method execution right now */
1402 
1403 		status = AE_CTRL_TERMINATE;
1404 		break;
1405 
1406 	case AML_NOOP_OP:
1407 
1408 		/* Just do nothing! */
1409 		break;
1410 
1411 	case AML_BREAK_POINT_OP:
1412 
1413 		/*
1414 		 * Set the single-step flag. This will cause the debugger (if present)
1415 		 * to break to the console within the AML debugger at the start of the
1416 		 * next AML instruction.
1417 		 */
1418 		ACPI_DEBUGGER_EXEC(acpi_gbl_cm_single_step = TRUE);
1419 		ACPI_DEBUGGER_EXEC(acpi_os_printf
1420 				   ("**break** Executed AML BreakPoint opcode\n"));
1421 
1422 		/* Call to the OSL in case OS wants a piece of the action */
1423 
1424 		status = acpi_os_signal(ACPI_SIGNAL_BREAKPOINT,
1425 					"Executed AML Breakpoint opcode");
1426 		break;
1427 
1428 	case AML_BREAK_OP:
1429 	case AML_CONTINUE_OP:	/* ACPI 2.0 */
1430 
1431 		/* Pop and delete control states until we find a while */
1432 
1433 		while (walk_state->control_state &&
1434 		       (walk_state->control_state->control.opcode !=
1435 			AML_WHILE_OP)) {
1436 			control_state =
1437 			    acpi_ut_pop_generic_state(&walk_state->
1438 						      control_state);
1439 			acpi_ut_delete_generic_state(control_state);
1440 		}
1441 
1442 		/* No while found? */
1443 
1444 		if (!walk_state->control_state) {
1445 			return (AE_AML_NO_WHILE);
1446 		}
1447 
1448 		/* Was: walk_state->aml_last_while = walk_state->control_state->Control.aml_predicate_start; */
1449 
1450 		walk_state->aml_last_while =
1451 		    walk_state->control_state->control.package_end;
1452 
1453 		/* Return status depending on opcode */
1454 
1455 		if (op->common.aml_opcode == AML_BREAK_OP) {
1456 			status = AE_CTRL_BREAK;
1457 		} else {
1458 			status = AE_CTRL_CONTINUE;
1459 		}
1460 		break;
1461 
1462 	default:
1463 
1464 		ACPI_ERROR((AE_INFO, "Unknown control opcode=%X Op=%p",
1465 			    op->common.aml_opcode, op));
1466 
1467 		status = AE_AML_BAD_OPCODE;
1468 		break;
1469 	}
1470 
1471 	return (status);
1472 }
1473