xref: /openbmc/linux/drivers/acpi/acpica/dsopcode.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /******************************************************************************
2  *
3  * Module Name: dsopcode - Dispatcher Op Region support and handling of
4  *                         "control" opcodes
5  *
6  *****************************************************************************/
7 
8 /*
9  * Copyright (C) 2000 - 2010, 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, node->parent,
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, node->parent,
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 namespace node in buffer object %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 namespace 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, node->parent,
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 0x%02X",
584 			    aml_opcode));
585 		status = AE_AML_BAD_OPCODE;
586 		goto cleanup;
587 	}
588 
589 	/* Entire field must fit within the current length of the buffer */
590 
591 	if ((bit_offset + bit_count) > (8 * (u32) buffer_desc->buffer.length)) {
592 		ACPI_ERROR((AE_INFO,
593 			    "Field [%4.4s] at %u exceeds Buffer [%4.4s] size %u (bits)",
594 			    acpi_ut_get_node_name(result_desc),
595 			    bit_offset + bit_count,
596 			    acpi_ut_get_node_name(buffer_desc->buffer.node),
597 			    8 * (u32) buffer_desc->buffer.length));
598 		status = AE_AML_BUFFER_LIMIT;
599 		goto cleanup;
600 	}
601 
602 	/*
603 	 * Initialize areas of the field object that are common to all fields
604 	 * For field_flags, use LOCK_RULE = 0 (NO_LOCK),
605 	 * UPDATE_RULE = 0 (UPDATE_PRESERVE)
606 	 */
607 	status = acpi_ex_prep_common_field_object(obj_desc, field_flags, 0,
608 						  bit_offset, bit_count);
609 	if (ACPI_FAILURE(status)) {
610 		goto cleanup;
611 	}
612 
613 	obj_desc->buffer_field.buffer_obj = buffer_desc;
614 
615 	/* Reference count for buffer_desc inherits obj_desc count */
616 
617 	buffer_desc->common.reference_count = (u16)
618 	    (buffer_desc->common.reference_count +
619 	     obj_desc->common.reference_count);
620 
621       cleanup:
622 
623 	/* Always delete the operands */
624 
625 	acpi_ut_remove_reference(offset_desc);
626 	acpi_ut_remove_reference(buffer_desc);
627 
628 	if (aml_opcode == AML_CREATE_FIELD_OP) {
629 		acpi_ut_remove_reference(length_desc);
630 	}
631 
632 	/* On failure, delete the result descriptor */
633 
634 	if (ACPI_FAILURE(status)) {
635 		acpi_ut_remove_reference(result_desc);	/* Result descriptor */
636 	} else {
637 		/* Now the address and length are valid for this buffer_field */
638 
639 		obj_desc->buffer_field.flags |= AOPOBJ_DATA_VALID;
640 	}
641 
642 	return_ACPI_STATUS(status);
643 }
644 
645 /*******************************************************************************
646  *
647  * FUNCTION:    acpi_ds_eval_buffer_field_operands
648  *
649  * PARAMETERS:  walk_state      - Current walk
650  *              Op              - A valid buffer_field Op object
651  *
652  * RETURN:      Status
653  *
654  * DESCRIPTION: Get buffer_field Buffer and Index
655  *              Called from acpi_ds_exec_end_op during buffer_field parse tree walk
656  *
657  ******************************************************************************/
658 
659 acpi_status
660 acpi_ds_eval_buffer_field_operands(struct acpi_walk_state *walk_state,
661 				   union acpi_parse_object *op)
662 {
663 	acpi_status status;
664 	union acpi_operand_object *obj_desc;
665 	struct acpi_namespace_node *node;
666 	union acpi_parse_object *next_op;
667 
668 	ACPI_FUNCTION_TRACE_PTR(ds_eval_buffer_field_operands, op);
669 
670 	/*
671 	 * This is where we evaluate the address and length fields of the
672 	 * create_xxx_field declaration
673 	 */
674 	node = op->common.node;
675 
676 	/* next_op points to the op that holds the Buffer */
677 
678 	next_op = op->common.value.arg;
679 
680 	/* Evaluate/create the address and length operands */
681 
682 	status = acpi_ds_create_operands(walk_state, next_op);
683 	if (ACPI_FAILURE(status)) {
684 		return_ACPI_STATUS(status);
685 	}
686 
687 	obj_desc = acpi_ns_get_attached_object(node);
688 	if (!obj_desc) {
689 		return_ACPI_STATUS(AE_NOT_EXIST);
690 	}
691 
692 	/* Resolve the operands */
693 
694 	status = acpi_ex_resolve_operands(op->common.aml_opcode,
695 					  ACPI_WALK_OPERANDS, walk_state);
696 	if (ACPI_FAILURE(status)) {
697 		ACPI_ERROR((AE_INFO, "(%s) bad operand(s), status 0x%X",
698 			    acpi_ps_get_opcode_name(op->common.aml_opcode),
699 			    status));
700 
701 		return_ACPI_STATUS(status);
702 	}
703 
704 	/* Initialize the Buffer Field */
705 
706 	if (op->common.aml_opcode == AML_CREATE_FIELD_OP) {
707 
708 		/* NOTE: Slightly different operands for this opcode */
709 
710 		status =
711 		    acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
712 					      walk_state->operands[0],
713 					      walk_state->operands[1],
714 					      walk_state->operands[2],
715 					      walk_state->operands[3]);
716 	} else {
717 		/* All other, create_xxx_field opcodes */
718 
719 		status =
720 		    acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
721 					      walk_state->operands[0],
722 					      walk_state->operands[1], NULL,
723 					      walk_state->operands[2]);
724 	}
725 
726 	return_ACPI_STATUS(status);
727 }
728 
729 /*******************************************************************************
730  *
731  * FUNCTION:    acpi_ds_eval_region_operands
732  *
733  * PARAMETERS:  walk_state      - Current walk
734  *              Op              - A valid region Op object
735  *
736  * RETURN:      Status
737  *
738  * DESCRIPTION: Get region address and length
739  *              Called from acpi_ds_exec_end_op during op_region parse tree walk
740  *
741  ******************************************************************************/
742 
743 acpi_status
744 acpi_ds_eval_region_operands(struct acpi_walk_state *walk_state,
745 			     union acpi_parse_object *op)
746 {
747 	acpi_status status;
748 	union acpi_operand_object *obj_desc;
749 	union acpi_operand_object *operand_desc;
750 	struct acpi_namespace_node *node;
751 	union acpi_parse_object *next_op;
752 
753 	ACPI_FUNCTION_TRACE_PTR(ds_eval_region_operands, op);
754 
755 	/*
756 	 * This is where we evaluate the address and length fields of the
757 	 * op_region declaration
758 	 */
759 	node = op->common.node;
760 
761 	/* next_op points to the op that holds the space_iD */
762 
763 	next_op = op->common.value.arg;
764 
765 	/* next_op points to address op */
766 
767 	next_op = next_op->common.next;
768 
769 	/* Evaluate/create the address and length operands */
770 
771 	status = acpi_ds_create_operands(walk_state, next_op);
772 	if (ACPI_FAILURE(status)) {
773 		return_ACPI_STATUS(status);
774 	}
775 
776 	/* Resolve the length and address operands to numbers */
777 
778 	status = acpi_ex_resolve_operands(op->common.aml_opcode,
779 					  ACPI_WALK_OPERANDS, walk_state);
780 	if (ACPI_FAILURE(status)) {
781 		return_ACPI_STATUS(status);
782 	}
783 
784 	obj_desc = acpi_ns_get_attached_object(node);
785 	if (!obj_desc) {
786 		return_ACPI_STATUS(AE_NOT_EXIST);
787 	}
788 
789 	/*
790 	 * Get the length operand and save it
791 	 * (at Top of stack)
792 	 */
793 	operand_desc = walk_state->operands[walk_state->num_operands - 1];
794 
795 	obj_desc->region.length = (u32) operand_desc->integer.value;
796 	acpi_ut_remove_reference(operand_desc);
797 
798 	/*
799 	 * Get the address and save it
800 	 * (at top of stack - 1)
801 	 */
802 	operand_desc = walk_state->operands[walk_state->num_operands - 2];
803 
804 	obj_desc->region.address = (acpi_physical_address)
805 	    operand_desc->integer.value;
806 	acpi_ut_remove_reference(operand_desc);
807 
808 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
809 			  obj_desc,
810 			  ACPI_FORMAT_NATIVE_UINT(obj_desc->region.address),
811 			  obj_desc->region.length));
812 
813 	/* Now the address and length are valid for this opregion */
814 
815 	obj_desc->region.flags |= AOPOBJ_DATA_VALID;
816 
817 	return_ACPI_STATUS(status);
818 }
819 
820 /*******************************************************************************
821  *
822  * FUNCTION:    acpi_ds_eval_table_region_operands
823  *
824  * PARAMETERS:  walk_state      - Current walk
825  *              Op              - A valid region Op object
826  *
827  * RETURN:      Status
828  *
829  * DESCRIPTION: Get region address and length
830  *              Called from acpi_ds_exec_end_op during data_table_region parse tree walk
831  *
832  ******************************************************************************/
833 
834 acpi_status
835 acpi_ds_eval_table_region_operands(struct acpi_walk_state *walk_state,
836 				   union acpi_parse_object *op)
837 {
838 	acpi_status status;
839 	union acpi_operand_object *obj_desc;
840 	union acpi_operand_object **operand;
841 	struct acpi_namespace_node *node;
842 	union acpi_parse_object *next_op;
843 	u32 table_index;
844 	struct acpi_table_header *table;
845 
846 	ACPI_FUNCTION_TRACE_PTR(ds_eval_table_region_operands, op);
847 
848 	/*
849 	 * This is where we evaluate the signature_string and oem_iDString
850 	 * and oem_table_iDString of the data_table_region declaration
851 	 */
852 	node = op->common.node;
853 
854 	/* next_op points to signature_string op */
855 
856 	next_op = op->common.value.arg;
857 
858 	/*
859 	 * Evaluate/create the signature_string and oem_iDString
860 	 * and oem_table_iDString operands
861 	 */
862 	status = acpi_ds_create_operands(walk_state, next_op);
863 	if (ACPI_FAILURE(status)) {
864 		return_ACPI_STATUS(status);
865 	}
866 
867 	/*
868 	 * Resolve the signature_string and oem_iDString
869 	 * and oem_table_iDString operands
870 	 */
871 	status = acpi_ex_resolve_operands(op->common.aml_opcode,
872 					  ACPI_WALK_OPERANDS, walk_state);
873 	if (ACPI_FAILURE(status)) {
874 		return_ACPI_STATUS(status);
875 	}
876 
877 	operand = &walk_state->operands[0];
878 
879 	/* Find the ACPI table */
880 
881 	status = acpi_tb_find_table(operand[0]->string.pointer,
882 				    operand[1]->string.pointer,
883 				    operand[2]->string.pointer, &table_index);
884 	if (ACPI_FAILURE(status)) {
885 		return_ACPI_STATUS(status);
886 	}
887 
888 	acpi_ut_remove_reference(operand[0]);
889 	acpi_ut_remove_reference(operand[1]);
890 	acpi_ut_remove_reference(operand[2]);
891 
892 	status = acpi_get_table_by_index(table_index, &table);
893 	if (ACPI_FAILURE(status)) {
894 		return_ACPI_STATUS(status);
895 	}
896 
897 	obj_desc = acpi_ns_get_attached_object(node);
898 	if (!obj_desc) {
899 		return_ACPI_STATUS(AE_NOT_EXIST);
900 	}
901 
902 	obj_desc->region.address =
903 	    (acpi_physical_address) ACPI_TO_INTEGER(table);
904 	obj_desc->region.length = table->length;
905 
906 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
907 			  obj_desc,
908 			  ACPI_FORMAT_NATIVE_UINT(obj_desc->region.address),
909 			  obj_desc->region.length));
910 
911 	/* Now the address and length are valid for this opregion */
912 
913 	obj_desc->region.flags |= AOPOBJ_DATA_VALID;
914 
915 	return_ACPI_STATUS(status);
916 }
917 
918 /*******************************************************************************
919  *
920  * FUNCTION:    acpi_ds_eval_data_object_operands
921  *
922  * PARAMETERS:  walk_state      - Current walk
923  *              Op              - A valid data_object Op object
924  *              obj_desc        - data_object
925  *
926  * RETURN:      Status
927  *
928  * DESCRIPTION: Get the operands and complete the following data object types:
929  *              Buffer, Package.
930  *
931  ******************************************************************************/
932 
933 acpi_status
934 acpi_ds_eval_data_object_operands(struct acpi_walk_state *walk_state,
935 				  union acpi_parse_object *op,
936 				  union acpi_operand_object *obj_desc)
937 {
938 	acpi_status status;
939 	union acpi_operand_object *arg_desc;
940 	u32 length;
941 
942 	ACPI_FUNCTION_TRACE(ds_eval_data_object_operands);
943 
944 	/* The first operand (for all of these data objects) is the length */
945 
946 	/*
947 	 * Set proper index into operand stack for acpi_ds_obj_stack_push
948 	 * invoked inside acpi_ds_create_operand.
949 	 */
950 	walk_state->operand_index = walk_state->num_operands;
951 
952 	status = acpi_ds_create_operand(walk_state, op->common.value.arg, 1);
953 	if (ACPI_FAILURE(status)) {
954 		return_ACPI_STATUS(status);
955 	}
956 
957 	status = acpi_ex_resolve_operands(walk_state->opcode,
958 					  &(walk_state->
959 					    operands[walk_state->num_operands -
960 						     1]), walk_state);
961 	if (ACPI_FAILURE(status)) {
962 		return_ACPI_STATUS(status);
963 	}
964 
965 	/* Extract length operand */
966 
967 	arg_desc = walk_state->operands[walk_state->num_operands - 1];
968 	length = (u32) arg_desc->integer.value;
969 
970 	/* Cleanup for length operand */
971 
972 	status = acpi_ds_obj_stack_pop(1, walk_state);
973 	if (ACPI_FAILURE(status)) {
974 		return_ACPI_STATUS(status);
975 	}
976 
977 	acpi_ut_remove_reference(arg_desc);
978 
979 	/*
980 	 * Create the actual data object
981 	 */
982 	switch (op->common.aml_opcode) {
983 	case AML_BUFFER_OP:
984 
985 		status =
986 		    acpi_ds_build_internal_buffer_obj(walk_state, op, length,
987 						      &obj_desc);
988 		break;
989 
990 	case AML_PACKAGE_OP:
991 	case AML_VAR_PACKAGE_OP:
992 
993 		status =
994 		    acpi_ds_build_internal_package_obj(walk_state, op, length,
995 						       &obj_desc);
996 		break;
997 
998 	default:
999 		return_ACPI_STATUS(AE_AML_BAD_OPCODE);
1000 	}
1001 
1002 	if (ACPI_SUCCESS(status)) {
1003 		/*
1004 		 * Return the object in the walk_state, unless the parent is a package -
1005 		 * in this case, the return object will be stored in the parse tree
1006 		 * for the package.
1007 		 */
1008 		if ((!op->common.parent) ||
1009 		    ((op->common.parent->common.aml_opcode != AML_PACKAGE_OP) &&
1010 		     (op->common.parent->common.aml_opcode !=
1011 		      AML_VAR_PACKAGE_OP)
1012 		     && (op->common.parent->common.aml_opcode != AML_NAME_OP))) {
1013 			walk_state->result_obj = obj_desc;
1014 		}
1015 	}
1016 
1017 	return_ACPI_STATUS(status);
1018 }
1019 
1020 /*******************************************************************************
1021  *
1022  * FUNCTION:    acpi_ds_eval_bank_field_operands
1023  *
1024  * PARAMETERS:  walk_state      - Current walk
1025  *              Op              - A valid bank_field Op object
1026  *
1027  * RETURN:      Status
1028  *
1029  * DESCRIPTION: Get bank_field bank_value
1030  *              Called from acpi_ds_exec_end_op during bank_field parse tree walk
1031  *
1032  ******************************************************************************/
1033 
1034 acpi_status
1035 acpi_ds_eval_bank_field_operands(struct acpi_walk_state *walk_state,
1036 				 union acpi_parse_object *op)
1037 {
1038 	acpi_status status;
1039 	union acpi_operand_object *obj_desc;
1040 	union acpi_operand_object *operand_desc;
1041 	struct acpi_namespace_node *node;
1042 	union acpi_parse_object *next_op;
1043 	union acpi_parse_object *arg;
1044 
1045 	ACPI_FUNCTION_TRACE_PTR(ds_eval_bank_field_operands, op);
1046 
1047 	/*
1048 	 * This is where we evaluate the bank_value field of the
1049 	 * bank_field declaration
1050 	 */
1051 
1052 	/* next_op points to the op that holds the Region */
1053 
1054 	next_op = op->common.value.arg;
1055 
1056 	/* next_op points to the op that holds the Bank Register */
1057 
1058 	next_op = next_op->common.next;
1059 
1060 	/* next_op points to the op that holds the Bank Value */
1061 
1062 	next_op = next_op->common.next;
1063 
1064 	/*
1065 	 * Set proper index into operand stack for acpi_ds_obj_stack_push
1066 	 * invoked inside acpi_ds_create_operand.
1067 	 *
1068 	 * We use walk_state->Operands[0] to store the evaluated bank_value
1069 	 */
1070 	walk_state->operand_index = 0;
1071 
1072 	status = acpi_ds_create_operand(walk_state, next_op, 0);
1073 	if (ACPI_FAILURE(status)) {
1074 		return_ACPI_STATUS(status);
1075 	}
1076 
1077 	status = acpi_ex_resolve_to_value(&walk_state->operands[0], walk_state);
1078 	if (ACPI_FAILURE(status)) {
1079 		return_ACPI_STATUS(status);
1080 	}
1081 
1082 	ACPI_DUMP_OPERANDS(ACPI_WALK_OPERANDS,
1083 			   acpi_ps_get_opcode_name(op->common.aml_opcode), 1);
1084 	/*
1085 	 * Get the bank_value operand and save it
1086 	 * (at Top of stack)
1087 	 */
1088 	operand_desc = walk_state->operands[0];
1089 
1090 	/* Arg points to the start Bank Field */
1091 
1092 	arg = acpi_ps_get_arg(op, 4);
1093 	while (arg) {
1094 
1095 		/* Ignore OFFSET and ACCESSAS terms here */
1096 
1097 		if (arg->common.aml_opcode == AML_INT_NAMEDFIELD_OP) {
1098 			node = arg->common.node;
1099 
1100 			obj_desc = acpi_ns_get_attached_object(node);
1101 			if (!obj_desc) {
1102 				return_ACPI_STATUS(AE_NOT_EXIST);
1103 			}
1104 
1105 			obj_desc->bank_field.value =
1106 			    (u32) operand_desc->integer.value;
1107 		}
1108 
1109 		/* Move to next field in the list */
1110 
1111 		arg = arg->common.next;
1112 	}
1113 
1114 	acpi_ut_remove_reference(operand_desc);
1115 	return_ACPI_STATUS(status);
1116 }
1117 
1118 /*******************************************************************************
1119  *
1120  * FUNCTION:    acpi_ds_exec_begin_control_op
1121  *
1122  * PARAMETERS:  walk_list       - The list that owns the walk stack
1123  *              Op              - The control Op
1124  *
1125  * RETURN:      Status
1126  *
1127  * DESCRIPTION: Handles all control ops encountered during control method
1128  *              execution.
1129  *
1130  ******************************************************************************/
1131 
1132 acpi_status
1133 acpi_ds_exec_begin_control_op(struct acpi_walk_state *walk_state,
1134 			      union acpi_parse_object *op)
1135 {
1136 	acpi_status status = AE_OK;
1137 	union acpi_generic_state *control_state;
1138 
1139 	ACPI_FUNCTION_NAME(ds_exec_begin_control_op);
1140 
1141 	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "Op=%p Opcode=%2.2X State=%p\n", op,
1142 			  op->common.aml_opcode, walk_state));
1143 
1144 	switch (op->common.aml_opcode) {
1145 	case AML_WHILE_OP:
1146 
1147 		/*
1148 		 * If this is an additional iteration of a while loop, continue.
1149 		 * There is no need to allocate a new control state.
1150 		 */
1151 		if (walk_state->control_state) {
1152 			if (walk_state->control_state->control.aml_predicate_start
1153 				== (walk_state->parser_state.aml - 1)) {
1154 
1155 				/* Reset the state to start-of-loop */
1156 
1157 				walk_state->control_state->common.state =
1158 				    ACPI_CONTROL_CONDITIONAL_EXECUTING;
1159 				break;
1160 			}
1161 		}
1162 
1163 		/*lint -fallthrough */
1164 
1165 	case AML_IF_OP:
1166 
1167 		/*
1168 		 * IF/WHILE: Create a new control state to manage these
1169 		 * constructs. We need to manage these as a stack, in order
1170 		 * to handle nesting.
1171 		 */
1172 		control_state = acpi_ut_create_control_state();
1173 		if (!control_state) {
1174 			status = AE_NO_MEMORY;
1175 			break;
1176 		}
1177 		/*
1178 		 * Save a pointer to the predicate for multiple executions
1179 		 * of a loop
1180 		 */
1181 		control_state->control.aml_predicate_start =
1182 		    walk_state->parser_state.aml - 1;
1183 		control_state->control.package_end =
1184 		    walk_state->parser_state.pkg_end;
1185 		control_state->control.opcode = op->common.aml_opcode;
1186 
1187 		/* Push the control state on this walk's control stack */
1188 
1189 		acpi_ut_push_generic_state(&walk_state->control_state,
1190 					   control_state);
1191 		break;
1192 
1193 	case AML_ELSE_OP:
1194 
1195 		/* Predicate is in the state object */
1196 		/* If predicate is true, the IF was executed, ignore ELSE part */
1197 
1198 		if (walk_state->last_predicate) {
1199 			status = AE_CTRL_TRUE;
1200 		}
1201 
1202 		break;
1203 
1204 	case AML_RETURN_OP:
1205 
1206 		break;
1207 
1208 	default:
1209 		break;
1210 	}
1211 
1212 	return (status);
1213 }
1214 
1215 /*******************************************************************************
1216  *
1217  * FUNCTION:    acpi_ds_exec_end_control_op
1218  *
1219  * PARAMETERS:  walk_list       - The list that owns the walk stack
1220  *              Op              - The control Op
1221  *
1222  * RETURN:      Status
1223  *
1224  * DESCRIPTION: Handles all control ops encountered during control method
1225  *              execution.
1226  *
1227  ******************************************************************************/
1228 
1229 acpi_status
1230 acpi_ds_exec_end_control_op(struct acpi_walk_state * walk_state,
1231 			    union acpi_parse_object * op)
1232 {
1233 	acpi_status status = AE_OK;
1234 	union acpi_generic_state *control_state;
1235 
1236 	ACPI_FUNCTION_NAME(ds_exec_end_control_op);
1237 
1238 	switch (op->common.aml_opcode) {
1239 	case AML_IF_OP:
1240 
1241 		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "[IF_OP] Op=%p\n", op));
1242 
1243 		/*
1244 		 * Save the result of the predicate in case there is an
1245 		 * ELSE to come
1246 		 */
1247 		walk_state->last_predicate =
1248 		    (u8) walk_state->control_state->common.value;
1249 
1250 		/*
1251 		 * Pop the control state that was created at the start
1252 		 * of the IF and free it
1253 		 */
1254 		control_state =
1255 		    acpi_ut_pop_generic_state(&walk_state->control_state);
1256 		acpi_ut_delete_generic_state(control_state);
1257 		break;
1258 
1259 	case AML_ELSE_OP:
1260 
1261 		break;
1262 
1263 	case AML_WHILE_OP:
1264 
1265 		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH, "[WHILE_OP] Op=%p\n", op));
1266 
1267 		control_state = walk_state->control_state;
1268 		if (control_state->common.value) {
1269 
1270 			/* Predicate was true, the body of the loop was just executed */
1271 
1272 			/*
1273 			 * This loop counter mechanism allows the interpreter to escape
1274 			 * possibly infinite loops. This can occur in poorly written AML
1275 			 * when the hardware does not respond within a while loop and the
1276 			 * loop does not implement a timeout.
1277 			 */
1278 			control_state->control.loop_count++;
1279 			if (control_state->control.loop_count >
1280 				ACPI_MAX_LOOP_ITERATIONS) {
1281 				status = AE_AML_INFINITE_LOOP;
1282 				break;
1283 			}
1284 
1285 			/*
1286 			 * Go back and evaluate the predicate and maybe execute the loop
1287 			 * another time
1288 			 */
1289 			status = AE_CTRL_PENDING;
1290 			walk_state->aml_last_while =
1291 			    control_state->control.aml_predicate_start;
1292 			break;
1293 		}
1294 
1295 		/* Predicate was false, terminate this while loop */
1296 
1297 		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
1298 				  "[WHILE_OP] termination! Op=%p\n", op));
1299 
1300 		/* Pop this control state and free it */
1301 
1302 		control_state =
1303 		    acpi_ut_pop_generic_state(&walk_state->control_state);
1304 		acpi_ut_delete_generic_state(control_state);
1305 		break;
1306 
1307 	case AML_RETURN_OP:
1308 
1309 		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
1310 				  "[RETURN_OP] Op=%p Arg=%p\n", op,
1311 				  op->common.value.arg));
1312 
1313 		/*
1314 		 * One optional operand -- the return value
1315 		 * It can be either an immediate operand or a result that
1316 		 * has been bubbled up the tree
1317 		 */
1318 		if (op->common.value.arg) {
1319 
1320 			/* Since we have a real Return(), delete any implicit return */
1321 
1322 			acpi_ds_clear_implicit_return(walk_state);
1323 
1324 			/* Return statement has an immediate operand */
1325 
1326 			status =
1327 			    acpi_ds_create_operands(walk_state,
1328 						    op->common.value.arg);
1329 			if (ACPI_FAILURE(status)) {
1330 				return (status);
1331 			}
1332 
1333 			/*
1334 			 * If value being returned is a Reference (such as
1335 			 * an arg or local), resolve it now because it may
1336 			 * cease to exist at the end of the method.
1337 			 */
1338 			status =
1339 			    acpi_ex_resolve_to_value(&walk_state->operands[0],
1340 						     walk_state);
1341 			if (ACPI_FAILURE(status)) {
1342 				return (status);
1343 			}
1344 
1345 			/*
1346 			 * Get the return value and save as the last result
1347 			 * value.  This is the only place where walk_state->return_desc
1348 			 * is set to anything other than zero!
1349 			 */
1350 			walk_state->return_desc = walk_state->operands[0];
1351 		} else if (walk_state->result_count) {
1352 
1353 			/* Since we have a real Return(), delete any implicit return */
1354 
1355 			acpi_ds_clear_implicit_return(walk_state);
1356 
1357 			/*
1358 			 * The return value has come from a previous calculation.
1359 			 *
1360 			 * If value being returned is a Reference (such as
1361 			 * an arg or local), resolve it now because it may
1362 			 * cease to exist at the end of the method.
1363 			 *
1364 			 * Allow references created by the Index operator to return unchanged.
1365 			 */
1366 			if ((ACPI_GET_DESCRIPTOR_TYPE
1367 			     (walk_state->results->results.obj_desc[0]) ==
1368 			     ACPI_DESC_TYPE_OPERAND)
1369 			    && ((walk_state->results->results.obj_desc[0])->
1370 				common.type == ACPI_TYPE_LOCAL_REFERENCE)
1371 			    && ((walk_state->results->results.obj_desc[0])->
1372 				reference.class != ACPI_REFCLASS_INDEX)) {
1373 				status =
1374 				    acpi_ex_resolve_to_value(&walk_state->
1375 							     results->results.
1376 							     obj_desc[0],
1377 							     walk_state);
1378 				if (ACPI_FAILURE(status)) {
1379 					return (status);
1380 				}
1381 			}
1382 
1383 			walk_state->return_desc =
1384 			    walk_state->results->results.obj_desc[0];
1385 		} else {
1386 			/* No return operand */
1387 
1388 			if (walk_state->num_operands) {
1389 				acpi_ut_remove_reference(walk_state->
1390 							 operands[0]);
1391 			}
1392 
1393 			walk_state->operands[0] = NULL;
1394 			walk_state->num_operands = 0;
1395 			walk_state->return_desc = NULL;
1396 		}
1397 
1398 		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
1399 				  "Completed RETURN_OP State=%p, RetVal=%p\n",
1400 				  walk_state, walk_state->return_desc));
1401 
1402 		/* End the control method execution right now */
1403 
1404 		status = AE_CTRL_TERMINATE;
1405 		break;
1406 
1407 	case AML_NOOP_OP:
1408 
1409 		/* Just do nothing! */
1410 		break;
1411 
1412 	case AML_BREAK_POINT_OP:
1413 
1414 		/*
1415 		 * Set the single-step flag. This will cause the debugger (if present)
1416 		 * to break to the console within the AML debugger at the start of the
1417 		 * next AML instruction.
1418 		 */
1419 		ACPI_DEBUGGER_EXEC(acpi_gbl_cm_single_step = TRUE);
1420 		ACPI_DEBUGGER_EXEC(acpi_os_printf
1421 				   ("**break** Executed AML BreakPoint opcode\n"));
1422 
1423 		/* Call to the OSL in case OS wants a piece of the action */
1424 
1425 		status = acpi_os_signal(ACPI_SIGNAL_BREAKPOINT,
1426 					"Executed AML Breakpoint opcode");
1427 		break;
1428 
1429 	case AML_BREAK_OP:
1430 	case AML_CONTINUE_OP:	/* ACPI 2.0 */
1431 
1432 		/* Pop and delete control states until we find a while */
1433 
1434 		while (walk_state->control_state &&
1435 		       (walk_state->control_state->control.opcode !=
1436 			AML_WHILE_OP)) {
1437 			control_state =
1438 			    acpi_ut_pop_generic_state(&walk_state->
1439 						      control_state);
1440 			acpi_ut_delete_generic_state(control_state);
1441 		}
1442 
1443 		/* No while found? */
1444 
1445 		if (!walk_state->control_state) {
1446 			return (AE_AML_NO_WHILE);
1447 		}
1448 
1449 		/* Was: walk_state->aml_last_while = walk_state->control_state->Control.aml_predicate_start; */
1450 
1451 		walk_state->aml_last_while =
1452 		    walk_state->control_state->control.package_end;
1453 
1454 		/* Return status depending on opcode */
1455 
1456 		if (op->common.aml_opcode == AML_BREAK_OP) {
1457 			status = AE_CTRL_BREAK;
1458 		} else {
1459 			status = AE_CTRL_CONTINUE;
1460 		}
1461 		break;
1462 
1463 	default:
1464 
1465 		ACPI_ERROR((AE_INFO, "Unknown control opcode=0x%X Op=%p",
1466 			    op->common.aml_opcode, op));
1467 
1468 		status = AE_AML_BAD_OPCODE;
1469 		break;
1470 	}
1471 
1472 	return (status);
1473 }
1474