xref: /openbmc/linux/drivers/acpi/acpica/dsopcode.c (revision be709d48)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: dsopcode - Dispatcher support for regions and fields
5  *
6  * Copyright (C) 2000 - 2019, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acparser.h"
13 #include "amlcode.h"
14 #include "acdispat.h"
15 #include "acinterp.h"
16 #include "acnamesp.h"
17 #include "acevents.h"
18 #include "actables.h"
19 
20 #define _COMPONENT          ACPI_DISPATCHER
21 ACPI_MODULE_NAME("dsopcode")
22 
23 /* Local prototypes */
24 static acpi_status
25 acpi_ds_init_buffer_field(u16 aml_opcode,
26 			  union acpi_operand_object *obj_desc,
27 			  union acpi_operand_object *buffer_desc,
28 			  union acpi_operand_object *offset_desc,
29 			  union acpi_operand_object *length_desc,
30 			  union acpi_operand_object *result_desc);
31 
32 /*******************************************************************************
33  *
34  * FUNCTION:    acpi_ds_initialize_region
35  *
36  * PARAMETERS:  obj_handle      - Region namespace node
37  *
38  * RETURN:      Status
39  *
40  * DESCRIPTION: Front end to ev_initialize_region
41  *
42  ******************************************************************************/
43 
44 acpi_status acpi_ds_initialize_region(acpi_handle obj_handle)
45 {
46 	union acpi_operand_object *obj_desc;
47 	acpi_status status;
48 
49 	obj_desc = acpi_ns_get_attached_object(obj_handle);
50 
51 	/* Namespace is NOT locked */
52 
53 	status = acpi_ev_initialize_region(obj_desc);
54 	return (status);
55 }
56 
57 /*******************************************************************************
58  *
59  * FUNCTION:    acpi_ds_init_buffer_field
60  *
61  * PARAMETERS:  aml_opcode      - create_xxx_field
62  *              obj_desc        - buffer_field object
63  *              buffer_desc     - Host Buffer
64  *              offset_desc     - Offset into buffer
65  *              length_desc     - Length of field (CREATE_FIELD_OP only)
66  *              result_desc     - Where to store the result
67  *
68  * RETURN:      Status
69  *
70  * DESCRIPTION: Perform actual initialization of a buffer field
71  *
72  ******************************************************************************/
73 
74 static acpi_status
75 acpi_ds_init_buffer_field(u16 aml_opcode,
76 			  union acpi_operand_object *obj_desc,
77 			  union acpi_operand_object *buffer_desc,
78 			  union acpi_operand_object *offset_desc,
79 			  union acpi_operand_object *length_desc,
80 			  union acpi_operand_object *result_desc)
81 {
82 	u32 offset;
83 	u32 bit_offset;
84 	u32 bit_count;
85 	u8 field_flags;
86 	acpi_status status;
87 
88 	ACPI_FUNCTION_TRACE_PTR(ds_init_buffer_field, obj_desc);
89 
90 	/* Host object must be a Buffer */
91 
92 	if (buffer_desc->common.type != ACPI_TYPE_BUFFER) {
93 		ACPI_ERROR((AE_INFO,
94 			    "Target of Create Field is not a Buffer object - %s",
95 			    acpi_ut_get_object_type_name(buffer_desc)));
96 
97 		status = AE_AML_OPERAND_TYPE;
98 		goto cleanup;
99 	}
100 
101 	/*
102 	 * The last parameter to all of these opcodes (result_desc) started
103 	 * out as a name_string, and should therefore now be a NS node
104 	 * after resolution in acpi_ex_resolve_operands().
105 	 */
106 	if (ACPI_GET_DESCRIPTOR_TYPE(result_desc) != ACPI_DESC_TYPE_NAMED) {
107 		ACPI_ERROR((AE_INFO,
108 			    "(%s) destination not a NS Node [%s]",
109 			    acpi_ps_get_opcode_name(aml_opcode),
110 			    acpi_ut_get_descriptor_name(result_desc)));
111 
112 		status = AE_AML_OPERAND_TYPE;
113 		goto cleanup;
114 	}
115 
116 	offset = (u32) offset_desc->integer.value;
117 
118 	/*
119 	 * Setup the Bit offsets and counts, according to the opcode
120 	 */
121 	switch (aml_opcode) {
122 	case AML_CREATE_FIELD_OP:
123 
124 		/* Offset is in bits, count is in bits */
125 
126 		field_flags = AML_FIELD_ACCESS_BYTE;
127 		bit_offset = offset;
128 		bit_count = (u32) length_desc->integer.value;
129 
130 		/* Must have a valid (>0) bit count */
131 
132 		if (bit_count == 0) {
133 			ACPI_BIOS_ERROR((AE_INFO,
134 					 "Attempt to CreateField of length zero"));
135 			status = AE_AML_OPERAND_VALUE;
136 			goto cleanup;
137 		}
138 		break;
139 
140 	case AML_CREATE_BIT_FIELD_OP:
141 
142 		/* Offset is in bits, Field is one bit */
143 
144 		bit_offset = offset;
145 		bit_count = 1;
146 		field_flags = AML_FIELD_ACCESS_BYTE;
147 		break;
148 
149 	case AML_CREATE_BYTE_FIELD_OP:
150 
151 		/* Offset is in bytes, field is one byte */
152 
153 		bit_offset = 8 * offset;
154 		bit_count = 8;
155 		field_flags = AML_FIELD_ACCESS_BYTE;
156 		break;
157 
158 	case AML_CREATE_WORD_FIELD_OP:
159 
160 		/* Offset is in bytes, field is one word */
161 
162 		bit_offset = 8 * offset;
163 		bit_count = 16;
164 		field_flags = AML_FIELD_ACCESS_WORD;
165 		break;
166 
167 	case AML_CREATE_DWORD_FIELD_OP:
168 
169 		/* Offset is in bytes, field is one dword */
170 
171 		bit_offset = 8 * offset;
172 		bit_count = 32;
173 		field_flags = AML_FIELD_ACCESS_DWORD;
174 		break;
175 
176 	case AML_CREATE_QWORD_FIELD_OP:
177 
178 		/* Offset is in bytes, field is one qword */
179 
180 		bit_offset = 8 * offset;
181 		bit_count = 64;
182 		field_flags = AML_FIELD_ACCESS_QWORD;
183 		break;
184 
185 	default:
186 
187 		ACPI_ERROR((AE_INFO,
188 			    "Unknown field creation opcode 0x%02X",
189 			    aml_opcode));
190 		status = AE_AML_BAD_OPCODE;
191 		goto cleanup;
192 	}
193 
194 	/* Entire field must fit within the current length of the buffer */
195 
196 	if ((bit_offset + bit_count) > (8 * (u32)buffer_desc->buffer.length)) {
197 		status = AE_AML_BUFFER_LIMIT;
198 		ACPI_BIOS_EXCEPTION((AE_INFO, status,
199 				     "Field [%4.4s] at bit offset/length %u/%u "
200 				     "exceeds size of target Buffer (%u bits)",
201 				     acpi_ut_get_node_name(result_desc),
202 				     bit_offset, bit_count,
203 				     8 * (u32)buffer_desc->buffer.length));
204 		goto cleanup;
205 	}
206 
207 	/*
208 	 * Initialize areas of the field object that are common to all fields
209 	 * For field_flags, use LOCK_RULE = 0 (NO_LOCK),
210 	 * UPDATE_RULE = 0 (UPDATE_PRESERVE)
211 	 */
212 	status =
213 	    acpi_ex_prep_common_field_object(obj_desc, field_flags, 0,
214 					     bit_offset, bit_count);
215 	if (ACPI_FAILURE(status)) {
216 		goto cleanup;
217 	}
218 
219 	obj_desc->buffer_field.buffer_obj = buffer_desc;
220 
221 	/* Reference count for buffer_desc inherits obj_desc count */
222 
223 	buffer_desc->common.reference_count = (u16)
224 	    (buffer_desc->common.reference_count +
225 	     obj_desc->common.reference_count);
226 
227 cleanup:
228 
229 	/* Always delete the operands */
230 
231 	acpi_ut_remove_reference(offset_desc);
232 	acpi_ut_remove_reference(buffer_desc);
233 
234 	if (aml_opcode == AML_CREATE_FIELD_OP) {
235 		acpi_ut_remove_reference(length_desc);
236 	}
237 
238 	/* On failure, delete the result descriptor */
239 
240 	if (ACPI_FAILURE(status)) {
241 		acpi_ut_remove_reference(result_desc);	/* Result descriptor */
242 	} else {
243 		/* Now the address and length are valid for this buffer_field */
244 
245 		obj_desc->buffer_field.flags |= AOPOBJ_DATA_VALID;
246 	}
247 
248 	return_ACPI_STATUS(status);
249 }
250 
251 /*******************************************************************************
252  *
253  * FUNCTION:    acpi_ds_eval_buffer_field_operands
254  *
255  * PARAMETERS:  walk_state      - Current walk
256  *              op              - A valid buffer_field Op object
257  *
258  * RETURN:      Status
259  *
260  * DESCRIPTION: Get buffer_field Buffer and Index
261  *              Called from acpi_ds_exec_end_op during buffer_field parse tree walk
262  *
263  ******************************************************************************/
264 
265 acpi_status
266 acpi_ds_eval_buffer_field_operands(struct acpi_walk_state *walk_state,
267 				   union acpi_parse_object *op)
268 {
269 	acpi_status status;
270 	union acpi_operand_object *obj_desc;
271 	struct acpi_namespace_node *node;
272 	union acpi_parse_object *next_op;
273 
274 	ACPI_FUNCTION_TRACE_PTR(ds_eval_buffer_field_operands, op);
275 
276 	/*
277 	 * This is where we evaluate the address and length fields of the
278 	 * create_xxx_field declaration
279 	 */
280 	node = op->common.node;
281 
282 	/* next_op points to the op that holds the Buffer */
283 
284 	next_op = op->common.value.arg;
285 
286 	/* Evaluate/create the address and length operands */
287 
288 	status = acpi_ds_create_operands(walk_state, next_op);
289 	if (ACPI_FAILURE(status)) {
290 		return_ACPI_STATUS(status);
291 	}
292 
293 	obj_desc = acpi_ns_get_attached_object(node);
294 	if (!obj_desc) {
295 		return_ACPI_STATUS(AE_NOT_EXIST);
296 	}
297 
298 	/* Resolve the operands */
299 
300 	status =
301 	    acpi_ex_resolve_operands(op->common.aml_opcode, ACPI_WALK_OPERANDS,
302 				     walk_state);
303 	if (ACPI_FAILURE(status)) {
304 		ACPI_ERROR((AE_INFO, "(%s) bad operand(s), status 0x%X",
305 			    acpi_ps_get_opcode_name(op->common.aml_opcode),
306 			    status));
307 
308 		return_ACPI_STATUS(status);
309 	}
310 
311 	/* Initialize the Buffer Field */
312 
313 	if (op->common.aml_opcode == AML_CREATE_FIELD_OP) {
314 
315 		/* NOTE: Slightly different operands for this opcode */
316 
317 		status =
318 		    acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
319 					      walk_state->operands[0],
320 					      walk_state->operands[1],
321 					      walk_state->operands[2],
322 					      walk_state->operands[3]);
323 	} else {
324 		/* All other, create_xxx_field opcodes */
325 
326 		status =
327 		    acpi_ds_init_buffer_field(op->common.aml_opcode, obj_desc,
328 					      walk_state->operands[0],
329 					      walk_state->operands[1], NULL,
330 					      walk_state->operands[2]);
331 	}
332 
333 	return_ACPI_STATUS(status);
334 }
335 
336 /*******************************************************************************
337  *
338  * FUNCTION:    acpi_ds_eval_region_operands
339  *
340  * PARAMETERS:  walk_state      - Current walk
341  *              op              - A valid region Op object
342  *
343  * RETURN:      Status
344  *
345  * DESCRIPTION: Get region address and length
346  *              Called from acpi_ds_exec_end_op during op_region parse tree walk
347  *
348  ******************************************************************************/
349 
350 acpi_status
351 acpi_ds_eval_region_operands(struct acpi_walk_state *walk_state,
352 			     union acpi_parse_object *op)
353 {
354 	acpi_status status;
355 	union acpi_operand_object *obj_desc;
356 	union acpi_operand_object *operand_desc;
357 	struct acpi_namespace_node *node;
358 	union acpi_parse_object *next_op;
359 	acpi_adr_space_type space_id;
360 
361 	ACPI_FUNCTION_TRACE_PTR(ds_eval_region_operands, op);
362 
363 	/*
364 	 * This is where we evaluate the address and length fields of the
365 	 * op_region declaration
366 	 */
367 	node = op->common.node;
368 
369 	/* next_op points to the op that holds the space_ID */
370 
371 	next_op = op->common.value.arg;
372 	space_id = (acpi_adr_space_type)next_op->common.value.integer;
373 
374 	/* next_op points to address op */
375 
376 	next_op = next_op->common.next;
377 
378 	/* Evaluate/create the address and length operands */
379 
380 	status = acpi_ds_create_operands(walk_state, next_op);
381 	if (ACPI_FAILURE(status)) {
382 		return_ACPI_STATUS(status);
383 	}
384 
385 	/* Resolve the length and address operands to numbers */
386 
387 	status =
388 	    acpi_ex_resolve_operands(op->common.aml_opcode, ACPI_WALK_OPERANDS,
389 				     walk_state);
390 	if (ACPI_FAILURE(status)) {
391 		return_ACPI_STATUS(status);
392 	}
393 
394 	obj_desc = acpi_ns_get_attached_object(node);
395 	if (!obj_desc) {
396 		return_ACPI_STATUS(AE_NOT_EXIST);
397 	}
398 
399 	/*
400 	 * Get the length operand and save it
401 	 * (at Top of stack)
402 	 */
403 	operand_desc = walk_state->operands[walk_state->num_operands - 1];
404 
405 	obj_desc->region.length = (u32) operand_desc->integer.value;
406 	acpi_ut_remove_reference(operand_desc);
407 
408 	/* A zero-length operation region is unusable. Just warn */
409 
410 	if (!obj_desc->region.length
411 	    && (space_id < ACPI_NUM_PREDEFINED_REGIONS)) {
412 		ACPI_WARNING((AE_INFO,
413 			      "Operation Region [%4.4s] has zero length (SpaceId %X)",
414 			      node->name.ascii, space_id));
415 	}
416 
417 	/*
418 	 * Get the address and save it
419 	 * (at top of stack - 1)
420 	 */
421 	operand_desc = walk_state->operands[walk_state->num_operands - 2];
422 
423 	obj_desc->region.address = (acpi_physical_address)
424 	    operand_desc->integer.value;
425 	acpi_ut_remove_reference(operand_desc);
426 
427 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
428 			  obj_desc,
429 			  ACPI_FORMAT_UINT64(obj_desc->region.address),
430 			  obj_desc->region.length));
431 
432 	status = acpi_ut_add_address_range(obj_desc->region.space_id,
433 					   obj_desc->region.address,
434 					   obj_desc->region.length, node);
435 
436 	/* Now the address and length are valid for this opregion */
437 
438 	obj_desc->region.flags |= AOPOBJ_DATA_VALID;
439 	return_ACPI_STATUS(status);
440 }
441 
442 /*******************************************************************************
443  *
444  * FUNCTION:    acpi_ds_eval_table_region_operands
445  *
446  * PARAMETERS:  walk_state      - Current walk
447  *              op              - A valid region Op object
448  *
449  * RETURN:      Status
450  *
451  * DESCRIPTION: Get region address and length.
452  *              Called from acpi_ds_exec_end_op during data_table_region parse
453  *              tree walk.
454  *
455  ******************************************************************************/
456 
457 acpi_status
458 acpi_ds_eval_table_region_operands(struct acpi_walk_state *walk_state,
459 				   union acpi_parse_object *op)
460 {
461 	acpi_status status;
462 	union acpi_operand_object *obj_desc;
463 	union acpi_operand_object **operand;
464 	struct acpi_namespace_node *node;
465 	union acpi_parse_object *next_op;
466 	struct acpi_table_header *table;
467 	u32 table_index;
468 
469 	ACPI_FUNCTION_TRACE_PTR(ds_eval_table_region_operands, op);
470 
471 	/*
472 	 * This is where we evaluate the Signature string, oem_id string,
473 	 * and oem_table_id string of the Data Table Region declaration
474 	 */
475 	node = op->common.node;
476 
477 	/* next_op points to Signature string op */
478 
479 	next_op = op->common.value.arg;
480 
481 	/*
482 	 * Evaluate/create the Signature string, oem_id string,
483 	 * and oem_table_id string operands
484 	 */
485 	status = acpi_ds_create_operands(walk_state, next_op);
486 	if (ACPI_FAILURE(status)) {
487 		return_ACPI_STATUS(status);
488 	}
489 
490 	operand = &walk_state->operands[0];
491 
492 	/*
493 	 * Resolve the Signature string, oem_id string,
494 	 * and oem_table_id string operands
495 	 */
496 	status =
497 	    acpi_ex_resolve_operands(op->common.aml_opcode, ACPI_WALK_OPERANDS,
498 				     walk_state);
499 	if (ACPI_FAILURE(status)) {
500 		goto cleanup;
501 	}
502 
503 	/* Find the ACPI table */
504 
505 	status = acpi_tb_find_table(operand[0]->string.pointer,
506 				    operand[1]->string.pointer,
507 				    operand[2]->string.pointer, &table_index);
508 	if (ACPI_FAILURE(status)) {
509 		if (status == AE_NOT_FOUND) {
510 			ACPI_ERROR((AE_INFO,
511 				    "ACPI Table [%4.4s] OEM:(%s, %s) not found in RSDT/XSDT",
512 				    operand[0]->string.pointer,
513 				    operand[1]->string.pointer,
514 				    operand[2]->string.pointer));
515 		}
516 		goto cleanup;
517 	}
518 
519 	status = acpi_get_table_by_index(table_index, &table);
520 	if (ACPI_FAILURE(status)) {
521 		goto cleanup;
522 	}
523 
524 	obj_desc = acpi_ns_get_attached_object(node);
525 	if (!obj_desc) {
526 		status = AE_NOT_EXIST;
527 		goto cleanup;
528 	}
529 
530 	obj_desc->region.address = ACPI_PTR_TO_PHYSADDR(table);
531 	obj_desc->region.length = table->length;
532 
533 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "RgnObj %p Addr %8.8X%8.8X Len %X\n",
534 			  obj_desc,
535 			  ACPI_FORMAT_UINT64(obj_desc->region.address),
536 			  obj_desc->region.length));
537 
538 	/* Now the address and length are valid for this opregion */
539 
540 	obj_desc->region.flags |= AOPOBJ_DATA_VALID;
541 
542 cleanup:
543 	acpi_ut_remove_reference(operand[0]);
544 	acpi_ut_remove_reference(operand[1]);
545 	acpi_ut_remove_reference(operand[2]);
546 
547 	return_ACPI_STATUS(status);
548 }
549 
550 /*******************************************************************************
551  *
552  * FUNCTION:    acpi_ds_eval_data_object_operands
553  *
554  * PARAMETERS:  walk_state      - Current walk
555  *              op              - A valid data_object Op object
556  *              obj_desc        - data_object
557  *
558  * RETURN:      Status
559  *
560  * DESCRIPTION: Get the operands and complete the following data object types:
561  *              Buffer, Package.
562  *
563  ******************************************************************************/
564 
565 acpi_status
566 acpi_ds_eval_data_object_operands(struct acpi_walk_state *walk_state,
567 				  union acpi_parse_object *op,
568 				  union acpi_operand_object *obj_desc)
569 {
570 	acpi_status status;
571 	union acpi_operand_object *arg_desc;
572 	u32 length;
573 
574 	ACPI_FUNCTION_TRACE(ds_eval_data_object_operands);
575 
576 	/* The first operand (for all of these data objects) is the length */
577 
578 	/*
579 	 * Set proper index into operand stack for acpi_ds_obj_stack_push
580 	 * invoked inside acpi_ds_create_operand.
581 	 */
582 	walk_state->operand_index = walk_state->num_operands;
583 
584 	/* Ignore if child is not valid */
585 
586 	if (!op->common.value.arg) {
587 		ACPI_ERROR((AE_INFO,
588 			    "Missing child while evaluating opcode %4.4X, Op %p",
589 			    op->common.aml_opcode, op));
590 		return_ACPI_STATUS(AE_OK);
591 	}
592 
593 	status = acpi_ds_create_operand(walk_state, op->common.value.arg, 1);
594 	if (ACPI_FAILURE(status)) {
595 		return_ACPI_STATUS(status);
596 	}
597 
598 	status = acpi_ex_resolve_operands(walk_state->opcode,
599 					  &(walk_state->
600 					    operands[walk_state->num_operands -
601 						     1]), walk_state);
602 	if (ACPI_FAILURE(status)) {
603 		return_ACPI_STATUS(status);
604 	}
605 
606 	/* Extract length operand */
607 
608 	arg_desc = walk_state->operands[walk_state->num_operands - 1];
609 	length = (u32) arg_desc->integer.value;
610 
611 	/* Cleanup for length operand */
612 
613 	status = acpi_ds_obj_stack_pop(1, walk_state);
614 	if (ACPI_FAILURE(status)) {
615 		return_ACPI_STATUS(status);
616 	}
617 
618 	acpi_ut_remove_reference(arg_desc);
619 
620 	/*
621 	 * Create the actual data object
622 	 */
623 	switch (op->common.aml_opcode) {
624 	case AML_BUFFER_OP:
625 
626 		status =
627 		    acpi_ds_build_internal_buffer_obj(walk_state, op, length,
628 						      &obj_desc);
629 		break;
630 
631 	case AML_PACKAGE_OP:
632 	case AML_VARIABLE_PACKAGE_OP:
633 
634 		status =
635 		    acpi_ds_build_internal_package_obj(walk_state, op, length,
636 						       &obj_desc);
637 		break;
638 
639 	default:
640 
641 		return_ACPI_STATUS(AE_AML_BAD_OPCODE);
642 	}
643 
644 	if (ACPI_SUCCESS(status)) {
645 		/*
646 		 * Return the object in the walk_state, unless the parent is a package -
647 		 * in this case, the return object will be stored in the parse tree
648 		 * for the package.
649 		 */
650 		if ((!op->common.parent) ||
651 		    ((op->common.parent->common.aml_opcode != AML_PACKAGE_OP) &&
652 		     (op->common.parent->common.aml_opcode !=
653 		      AML_VARIABLE_PACKAGE_OP)
654 		     && (op->common.parent->common.aml_opcode !=
655 			 AML_NAME_OP))) {
656 			walk_state->result_obj = obj_desc;
657 		}
658 	}
659 
660 	return_ACPI_STATUS(status);
661 }
662 
663 /*******************************************************************************
664  *
665  * FUNCTION:    acpi_ds_eval_bank_field_operands
666  *
667  * PARAMETERS:  walk_state      - Current walk
668  *              op              - A valid bank_field Op object
669  *
670  * RETURN:      Status
671  *
672  * DESCRIPTION: Get bank_field bank_value
673  *              Called from acpi_ds_exec_end_op during bank_field parse tree walk
674  *
675  ******************************************************************************/
676 
677 acpi_status
678 acpi_ds_eval_bank_field_operands(struct acpi_walk_state *walk_state,
679 				 union acpi_parse_object *op)
680 {
681 	acpi_status status;
682 	union acpi_operand_object *obj_desc;
683 	union acpi_operand_object *operand_desc;
684 	struct acpi_namespace_node *node;
685 	union acpi_parse_object *next_op;
686 	union acpi_parse_object *arg;
687 
688 	ACPI_FUNCTION_TRACE_PTR(ds_eval_bank_field_operands, op);
689 
690 	/*
691 	 * This is where we evaluate the bank_value field of the
692 	 * bank_field declaration
693 	 */
694 
695 	/* next_op points to the op that holds the Region */
696 
697 	next_op = op->common.value.arg;
698 
699 	/* next_op points to the op that holds the Bank Register */
700 
701 	next_op = next_op->common.next;
702 
703 	/* next_op points to the op that holds the Bank Value */
704 
705 	next_op = next_op->common.next;
706 
707 	/*
708 	 * Set proper index into operand stack for acpi_ds_obj_stack_push
709 	 * invoked inside acpi_ds_create_operand.
710 	 *
711 	 * We use walk_state->Operands[0] to store the evaluated bank_value
712 	 */
713 	walk_state->operand_index = 0;
714 
715 	status = acpi_ds_create_operand(walk_state, next_op, 0);
716 	if (ACPI_FAILURE(status)) {
717 		return_ACPI_STATUS(status);
718 	}
719 
720 	status = acpi_ex_resolve_to_value(&walk_state->operands[0], walk_state);
721 	if (ACPI_FAILURE(status)) {
722 		return_ACPI_STATUS(status);
723 	}
724 
725 	ACPI_DUMP_OPERANDS(ACPI_WALK_OPERANDS,
726 			   acpi_ps_get_opcode_name(op->common.aml_opcode), 1);
727 	/*
728 	 * Get the bank_value operand and save it
729 	 * (at Top of stack)
730 	 */
731 	operand_desc = walk_state->operands[0];
732 
733 	/* Arg points to the start Bank Field */
734 
735 	arg = acpi_ps_get_arg(op, 4);
736 	while (arg) {
737 
738 		/* Ignore OFFSET and ACCESSAS terms here */
739 
740 		if (arg->common.aml_opcode == AML_INT_NAMEDFIELD_OP) {
741 			node = arg->common.node;
742 
743 			obj_desc = acpi_ns_get_attached_object(node);
744 			if (!obj_desc) {
745 				return_ACPI_STATUS(AE_NOT_EXIST);
746 			}
747 
748 			obj_desc->bank_field.value =
749 			    (u32) operand_desc->integer.value;
750 		}
751 
752 		/* Move to next field in the list */
753 
754 		arg = arg->common.next;
755 	}
756 
757 	acpi_ut_remove_reference(operand_desc);
758 	return_ACPI_STATUS(status);
759 }
760