1/******************************************************************************
2 *
3 * Module Name: dsfield - Dispatcher field routines
4 *
5 *****************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2015, Intel Corp.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions, and the following disclaimer,
16 *    without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 *    substantially similar to the "NO WARRANTY" disclaimer below
19 *    ("Disclaimer") and any redistribution must be conditioned upon
20 *    including a substantially similar Disclaimer requirement for further
21 *    binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 *    of any contributors may be used to endorse or promote products derived
24 *    from this software without specific prior written permission.
25 *
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
29 *
30 * NO WARRANTY
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
42 */
43
44#include <acpi/acpi.h>
45#include "accommon.h"
46#include "amlcode.h"
47#include "acdispat.h"
48#include "acinterp.h"
49#include "acnamesp.h"
50#include "acparser.h"
51
52#define _COMPONENT          ACPI_DISPATCHER
53ACPI_MODULE_NAME("dsfield")
54
55/* Local prototypes */
56#ifdef ACPI_ASL_COMPILER
57#include "acdisasm.h"
58static acpi_status
59acpi_ds_create_external_region(acpi_status lookup_status,
60			       union acpi_parse_object *op,
61			       char *path,
62			       struct acpi_walk_state *walk_state,
63			       struct acpi_namespace_node **node);
64#endif
65
66static acpi_status
67acpi_ds_get_field_names(struct acpi_create_field_info *info,
68			struct acpi_walk_state *walk_state,
69			union acpi_parse_object *arg);
70
71#ifdef ACPI_ASL_COMPILER
72/*******************************************************************************
73 *
74 * FUNCTION:    acpi_ds_create_external_region (iASL Disassembler only)
75 *
76 * PARAMETERS:  lookup_status   - Status from ns_lookup operation
77 *              op              - Op containing the Field definition and args
78 *              path            - Pathname of the region
79 *  `           walk_state      - Current method state
80 *              node            - Where the new region node is returned
81 *
82 * RETURN:      Status
83 *
84 * DESCRIPTION: Add region to the external list if NOT_FOUND. Create a new
85 *              region node/object.
86 *
87 ******************************************************************************/
88
89static acpi_status
90acpi_ds_create_external_region(acpi_status lookup_status,
91			       union acpi_parse_object *op,
92			       char *path,
93			       struct acpi_walk_state *walk_state,
94			       struct acpi_namespace_node **node)
95{
96	acpi_status status;
97	union acpi_operand_object *obj_desc;
98
99	if (lookup_status != AE_NOT_FOUND) {
100		return (lookup_status);
101	}
102
103	/*
104	 * Table disassembly:
105	 * operation_region not found. Generate an External for it, and
106	 * insert the name into the namespace.
107	 */
108	acpi_dm_add_op_to_external_list(op, path, ACPI_TYPE_REGION, 0, 0);
109	status = acpi_ns_lookup(walk_state->scope_info, path, ACPI_TYPE_REGION,
110				ACPI_IMODE_LOAD_PASS1, ACPI_NS_SEARCH_PARENT,
111				walk_state, node);
112	if (ACPI_FAILURE(status)) {
113		return (status);
114	}
115
116	/* Must create and install a region object for the new node */
117
118	obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_REGION);
119	if (!obj_desc) {
120		return (AE_NO_MEMORY);
121	}
122
123	obj_desc->region.node = *node;
124	status = acpi_ns_attach_object(*node, obj_desc, ACPI_TYPE_REGION);
125	return (status);
126}
127#endif
128
129/*******************************************************************************
130 *
131 * FUNCTION:    acpi_ds_create_buffer_field
132 *
133 * PARAMETERS:  op                  - Current parse op (create_XXField)
134 *              walk_state          - Current state
135 *
136 * RETURN:      Status
137 *
138 * DESCRIPTION: Execute the create_field operators:
139 *              create_bit_field_op,
140 *              create_byte_field_op,
141 *              create_word_field_op,
142 *              create_dword_field_op,
143 *              create_qword_field_op,
144 *              create_field_op     (all of which define a field in a buffer)
145 *
146 ******************************************************************************/
147
148acpi_status
149acpi_ds_create_buffer_field(union acpi_parse_object *op,
150			    struct acpi_walk_state *walk_state)
151{
152	union acpi_parse_object *arg;
153	struct acpi_namespace_node *node;
154	acpi_status status;
155	union acpi_operand_object *obj_desc;
156	union acpi_operand_object *second_desc = NULL;
157	u32 flags;
158
159	ACPI_FUNCTION_TRACE(ds_create_buffer_field);
160
161	/*
162	 * Get the name_string argument (name of the new buffer_field)
163	 */
164	if (op->common.aml_opcode == AML_CREATE_FIELD_OP) {
165
166		/* For create_field, name is the 4th argument */
167
168		arg = acpi_ps_get_arg(op, 3);
169	} else {
170		/* For all other create_XXXField operators, name is the 3rd argument */
171
172		arg = acpi_ps_get_arg(op, 2);
173	}
174
175	if (!arg) {
176		return_ACPI_STATUS(AE_AML_NO_OPERAND);
177	}
178
179	if (walk_state->deferred_node) {
180		node = walk_state->deferred_node;
181		status = AE_OK;
182	} else {
183		/* Execute flag should always be set when this function is entered */
184
185		if (!(walk_state->parse_flags & ACPI_PARSE_EXECUTE)) {
186			return_ACPI_STATUS(AE_AML_INTERNAL);
187		}
188
189		/* Creating new namespace node, should not already exist */
190
191		flags = ACPI_NS_NO_UPSEARCH | ACPI_NS_DONT_OPEN_SCOPE |
192		    ACPI_NS_ERROR_IF_FOUND;
193
194		/*
195		 * Mark node temporary if we are executing a normal control
196		 * method. (Don't mark if this is a module-level code method)
197		 */
198		if (walk_state->method_node &&
199		    !(walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL)) {
200			flags |= ACPI_NS_TEMPORARY;
201		}
202
203		/* Enter the name_string into the namespace */
204
205		status =
206		    acpi_ns_lookup(walk_state->scope_info,
207				   arg->common.value.string, ACPI_TYPE_ANY,
208				   ACPI_IMODE_LOAD_PASS1, flags, walk_state,
209				   &node);
210		if (ACPI_FAILURE(status)) {
211			ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
212			return_ACPI_STATUS(status);
213		}
214	}
215
216	/*
217	 * We could put the returned object (Node) on the object stack for later,
218	 * but for now, we will put it in the "op" object that the parser uses,
219	 * so we can get it again at the end of this scope.
220	 */
221	op->common.node = node;
222
223	/*
224	 * If there is no object attached to the node, this node was just created
225	 * and we need to create the field object. Otherwise, this was a lookup
226	 * of an existing node and we don't want to create the field object again.
227	 */
228	obj_desc = acpi_ns_get_attached_object(node);
229	if (obj_desc) {
230		return_ACPI_STATUS(AE_OK);
231	}
232
233	/*
234	 * The Field definition is not fully parsed at this time.
235	 * (We must save the address of the AML for the buffer and index operands)
236	 */
237
238	/* Create the buffer field object */
239
240	obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_BUFFER_FIELD);
241	if (!obj_desc) {
242		status = AE_NO_MEMORY;
243		goto cleanup;
244	}
245
246	/*
247	 * Remember location in AML stream of the field unit opcode and operands --
248	 * since the buffer and index operands must be evaluated.
249	 */
250	second_desc = obj_desc->common.next_object;
251	second_desc->extra.aml_start = op->named.data;
252	second_desc->extra.aml_length = op->named.length;
253	obj_desc->buffer_field.node = node;
254
255	/* Attach constructed field descriptors to parent node */
256
257	status = acpi_ns_attach_object(node, obj_desc, ACPI_TYPE_BUFFER_FIELD);
258	if (ACPI_FAILURE(status)) {
259		goto cleanup;
260	}
261
262cleanup:
263
264	/* Remove local reference to the object */
265
266	acpi_ut_remove_reference(obj_desc);
267	return_ACPI_STATUS(status);
268}
269
270/*******************************************************************************
271 *
272 * FUNCTION:    acpi_ds_get_field_names
273 *
274 * PARAMETERS:  info            - create_field info structure
275 *  `           walk_state      - Current method state
276 *              arg             - First parser arg for the field name list
277 *
278 * RETURN:      Status
279 *
280 * DESCRIPTION: Process all named fields in a field declaration. Names are
281 *              entered into the namespace.
282 *
283 ******************************************************************************/
284
285static acpi_status
286acpi_ds_get_field_names(struct acpi_create_field_info *info,
287			struct acpi_walk_state *walk_state,
288			union acpi_parse_object *arg)
289{
290	acpi_status status;
291	u64 position;
292	union acpi_parse_object *child;
293
294	ACPI_FUNCTION_TRACE_PTR(ds_get_field_names, info);
295
296	/* First field starts at bit zero */
297
298	info->field_bit_position = 0;
299
300	/* Process all elements in the field list (of parse nodes) */
301
302	while (arg) {
303		/*
304		 * Four types of field elements are handled:
305		 * 1) name - Enters a new named field into the namespace
306		 * 2) offset - specifies a bit offset
307		 * 3) access_as - changes the access mode/attributes
308		 * 4) connection - Associate a resource template with the field
309		 */
310		switch (arg->common.aml_opcode) {
311		case AML_INT_RESERVEDFIELD_OP:
312
313			position = (u64) info->field_bit_position
314			    + (u64) arg->common.value.size;
315
316			if (position > ACPI_UINT32_MAX) {
317				ACPI_ERROR((AE_INFO,
318					    "Bit offset within field too large (> 0xFFFFFFFF)"));
319				return_ACPI_STATUS(AE_SUPPORT);
320			}
321
322			info->field_bit_position = (u32) position;
323			break;
324
325		case AML_INT_ACCESSFIELD_OP:
326		case AML_INT_EXTACCESSFIELD_OP:
327			/*
328			 * Get new access_type, access_attribute, and access_length fields
329			 * -- to be used for all field units that follow, until the
330			 * end-of-field or another access_as keyword is encountered.
331			 * NOTE. These three bytes are encoded in the integer value
332			 * of the parseop for convenience.
333			 *
334			 * In field_flags, preserve the flag bits other than the
335			 * ACCESS_TYPE bits.
336			 */
337
338			/* access_type (byte_acc, word_acc, etc.) */
339
340			info->field_flags = (u8)
341			    ((info->
342			      field_flags & ~(AML_FIELD_ACCESS_TYPE_MASK)) |
343			     ((u8)((u32)(arg->common.value.integer & 0x07))));
344
345			/* access_attribute (attrib_quick, attrib_byte, etc.) */
346
347			info->attribute =
348			    (u8)((arg->common.value.integer >> 8) & 0xFF);
349
350			/* access_length (for serial/buffer protocols) */
351
352			info->access_length =
353			    (u8)((arg->common.value.integer >> 16) & 0xFF);
354			break;
355
356		case AML_INT_CONNECTION_OP:
357			/*
358			 * Clear any previous connection. New connection is used for all
359			 * fields that follow, similar to access_as
360			 */
361			info->resource_buffer = NULL;
362			info->connection_node = NULL;
363			info->pin_number_index = 0;
364
365			/*
366			 * A Connection() is either an actual resource descriptor (buffer)
367			 * or a named reference to a resource template
368			 */
369			child = arg->common.value.arg;
370			if (child->common.aml_opcode == AML_INT_BYTELIST_OP) {
371				info->resource_buffer = child->named.data;
372				info->resource_length =
373				    (u16)child->named.value.integer;
374			} else {
375				/* Lookup the Connection() namepath, it should already exist */
376
377				status = acpi_ns_lookup(walk_state->scope_info,
378							child->common.value.
379							name, ACPI_TYPE_ANY,
380							ACPI_IMODE_EXECUTE,
381							ACPI_NS_DONT_OPEN_SCOPE,
382							walk_state,
383							&info->connection_node);
384				if (ACPI_FAILURE(status)) {
385					ACPI_ERROR_NAMESPACE(child->common.
386							     value.name,
387							     status);
388					return_ACPI_STATUS(status);
389				}
390			}
391			break;
392
393		case AML_INT_NAMEDFIELD_OP:
394
395			/* Lookup the name, it should already exist */
396
397			status = acpi_ns_lookup(walk_state->scope_info,
398						(char *)&arg->named.name,
399						info->field_type,
400						ACPI_IMODE_EXECUTE,
401						ACPI_NS_DONT_OPEN_SCOPE,
402						walk_state, &info->field_node);
403			if (ACPI_FAILURE(status)) {
404				ACPI_ERROR_NAMESPACE((char *)&arg->named.name,
405						     status);
406				return_ACPI_STATUS(status);
407			} else {
408				arg->common.node = info->field_node;
409				info->field_bit_length = arg->common.value.size;
410
411				/*
412				 * If there is no object attached to the node, this node was
413				 * just created and we need to create the field object.
414				 * Otherwise, this was a lookup of an existing node and we
415				 * don't want to create the field object again.
416				 */
417				if (!acpi_ns_get_attached_object
418				    (info->field_node)) {
419					status = acpi_ex_prep_field_value(info);
420					if (ACPI_FAILURE(status)) {
421						return_ACPI_STATUS(status);
422					}
423				}
424			}
425
426			/* Keep track of bit position for the next field */
427
428			position = (u64) info->field_bit_position
429			    + (u64) arg->common.value.size;
430
431			if (position > ACPI_UINT32_MAX) {
432				ACPI_ERROR((AE_INFO,
433					    "Field [%4.4s] bit offset too large (> 0xFFFFFFFF)",
434					    ACPI_CAST_PTR(char,
435							  &info->field_node->
436							  name)));
437				return_ACPI_STATUS(AE_SUPPORT);
438			}
439
440			info->field_bit_position += info->field_bit_length;
441			info->pin_number_index++;	/* Index relative to previous Connection() */
442			break;
443
444		default:
445
446			ACPI_ERROR((AE_INFO,
447				    "Invalid opcode in field list: 0x%X",
448				    arg->common.aml_opcode));
449			return_ACPI_STATUS(AE_AML_BAD_OPCODE);
450		}
451
452		arg = arg->common.next;
453	}
454
455	return_ACPI_STATUS(AE_OK);
456}
457
458/*******************************************************************************
459 *
460 * FUNCTION:    acpi_ds_create_field
461 *
462 * PARAMETERS:  op              - Op containing the Field definition and args
463 *              region_node     - Object for the containing Operation Region
464 *  `           walk_state      - Current method state
465 *
466 * RETURN:      Status
467 *
468 * DESCRIPTION: Create a new field in the specified operation region
469 *
470 ******************************************************************************/
471
472acpi_status
473acpi_ds_create_field(union acpi_parse_object *op,
474		     struct acpi_namespace_node *region_node,
475		     struct acpi_walk_state *walk_state)
476{
477	acpi_status status;
478	union acpi_parse_object *arg;
479	struct acpi_create_field_info info;
480
481	ACPI_FUNCTION_TRACE_PTR(ds_create_field, op);
482
483	/* First arg is the name of the parent op_region (must already exist) */
484
485	arg = op->common.value.arg;
486
487	if (!region_node) {
488		status =
489		    acpi_ns_lookup(walk_state->scope_info,
490				   arg->common.value.name, ACPI_TYPE_REGION,
491				   ACPI_IMODE_EXECUTE, ACPI_NS_SEARCH_PARENT,
492				   walk_state, &region_node);
493#ifdef ACPI_ASL_COMPILER
494		status = acpi_ds_create_external_region(status, arg,
495							arg->common.value.name,
496							walk_state,
497							&region_node);
498#endif
499		if (ACPI_FAILURE(status)) {
500			ACPI_ERROR_NAMESPACE(arg->common.value.name, status);
501			return_ACPI_STATUS(status);
502		}
503	}
504
505	ACPI_MEMSET(&info, 0, sizeof(struct acpi_create_field_info));
506
507	/* Second arg is the field flags */
508
509	arg = arg->common.next;
510	info.field_flags = (u8) arg->common.value.integer;
511	info.attribute = 0;
512
513	/* Each remaining arg is a Named Field */
514
515	info.field_type = ACPI_TYPE_LOCAL_REGION_FIELD;
516	info.region_node = region_node;
517
518	status = acpi_ds_get_field_names(&info, walk_state, arg->common.next);
519	return_ACPI_STATUS(status);
520}
521
522/*******************************************************************************
523 *
524 * FUNCTION:    acpi_ds_init_field_objects
525 *
526 * PARAMETERS:  op              - Op containing the Field definition and args
527 *  `           walk_state      - Current method state
528 *
529 * RETURN:      Status
530 *
531 * DESCRIPTION: For each "Field Unit" name in the argument list that is
532 *              part of the field declaration, enter the name into the
533 *              namespace.
534 *
535 ******************************************************************************/
536
537acpi_status
538acpi_ds_init_field_objects(union acpi_parse_object *op,
539			   struct acpi_walk_state *walk_state)
540{
541	acpi_status status;
542	union acpi_parse_object *arg = NULL;
543	struct acpi_namespace_node *node;
544	u8 type = 0;
545	u32 flags;
546
547	ACPI_FUNCTION_TRACE_PTR(ds_init_field_objects, op);
548
549	/* Execute flag should always be set when this function is entered */
550
551	if (!(walk_state->parse_flags & ACPI_PARSE_EXECUTE)) {
552		if (walk_state->parse_flags & ACPI_PARSE_DEFERRED_OP) {
553
554			/* bank_field Op is deferred, just return OK */
555
556			return_ACPI_STATUS(AE_OK);
557		}
558
559		return_ACPI_STATUS(AE_AML_INTERNAL);
560	}
561
562	/*
563	 * Get the field_list argument for this opcode. This is the start of the
564	 * list of field elements.
565	 */
566	switch (walk_state->opcode) {
567	case AML_FIELD_OP:
568
569		arg = acpi_ps_get_arg(op, 2);
570		type = ACPI_TYPE_LOCAL_REGION_FIELD;
571		break;
572
573	case AML_BANK_FIELD_OP:
574
575		arg = acpi_ps_get_arg(op, 4);
576		type = ACPI_TYPE_LOCAL_BANK_FIELD;
577		break;
578
579	case AML_INDEX_FIELD_OP:
580
581		arg = acpi_ps_get_arg(op, 3);
582		type = ACPI_TYPE_LOCAL_INDEX_FIELD;
583		break;
584
585	default:
586
587		return_ACPI_STATUS(AE_BAD_PARAMETER);
588	}
589
590	/* Creating new namespace node(s), should not already exist */
591
592	flags = ACPI_NS_NO_UPSEARCH | ACPI_NS_DONT_OPEN_SCOPE |
593	    ACPI_NS_ERROR_IF_FOUND;
594
595	/*
596	 * Mark node(s) temporary if we are executing a normal control
597	 * method. (Don't mark if this is a module-level code method)
598	 */
599	if (walk_state->method_node &&
600	    !(walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL)) {
601		flags |= ACPI_NS_TEMPORARY;
602	}
603
604	/*
605	 * Walk the list of entries in the field_list
606	 * Note: field_list can be of zero length. In this case, Arg will be NULL.
607	 */
608	while (arg) {
609		/*
610		 * Ignore OFFSET/ACCESSAS/CONNECTION terms here; we are only interested
611		 * in the field names in order to enter them into the namespace.
612		 */
613		if (arg->common.aml_opcode == AML_INT_NAMEDFIELD_OP) {
614			status = acpi_ns_lookup(walk_state->scope_info,
615						(char *)&arg->named.name, type,
616						ACPI_IMODE_LOAD_PASS1, flags,
617						walk_state, &node);
618			if (ACPI_FAILURE(status)) {
619				ACPI_ERROR_NAMESPACE((char *)&arg->named.name,
620						     status);
621				if (status != AE_ALREADY_EXISTS) {
622					return_ACPI_STATUS(status);
623				}
624
625				/* Name already exists, just ignore this error */
626
627				status = AE_OK;
628			}
629
630			arg->common.node = node;
631		}
632
633		/* Get the next field element in the list */
634
635		arg = arg->common.next;
636	}
637
638	return_ACPI_STATUS(AE_OK);
639}
640
641/*******************************************************************************
642 *
643 * FUNCTION:    acpi_ds_create_bank_field
644 *
645 * PARAMETERS:  op              - Op containing the Field definition and args
646 *              region_node     - Object for the containing Operation Region
647 *              walk_state      - Current method state
648 *
649 * RETURN:      Status
650 *
651 * DESCRIPTION: Create a new bank field in the specified operation region
652 *
653 ******************************************************************************/
654
655acpi_status
656acpi_ds_create_bank_field(union acpi_parse_object *op,
657			  struct acpi_namespace_node *region_node,
658			  struct acpi_walk_state *walk_state)
659{
660	acpi_status status;
661	union acpi_parse_object *arg;
662	struct acpi_create_field_info info;
663
664	ACPI_FUNCTION_TRACE_PTR(ds_create_bank_field, op);
665
666	/* First arg is the name of the parent op_region (must already exist) */
667
668	arg = op->common.value.arg;
669	if (!region_node) {
670		status =
671		    acpi_ns_lookup(walk_state->scope_info,
672				   arg->common.value.name, ACPI_TYPE_REGION,
673				   ACPI_IMODE_EXECUTE, ACPI_NS_SEARCH_PARENT,
674				   walk_state, &region_node);
675#ifdef ACPI_ASL_COMPILER
676		status = acpi_ds_create_external_region(status, arg,
677							arg->common.value.name,
678							walk_state,
679							&region_node);
680#endif
681		if (ACPI_FAILURE(status)) {
682			ACPI_ERROR_NAMESPACE(arg->common.value.name, status);
683			return_ACPI_STATUS(status);
684		}
685	}
686
687	/* Second arg is the Bank Register (Field) (must already exist) */
688
689	arg = arg->common.next;
690	status =
691	    acpi_ns_lookup(walk_state->scope_info, arg->common.value.string,
692			   ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
693			   ACPI_NS_SEARCH_PARENT, walk_state,
694			   &info.register_node);
695	if (ACPI_FAILURE(status)) {
696		ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
697		return_ACPI_STATUS(status);
698	}
699
700	/*
701	 * Third arg is the bank_value
702	 * This arg is a term_arg, not a constant
703	 * It will be evaluated later, by acpi_ds_eval_bank_field_operands
704	 */
705	arg = arg->common.next;
706
707	/* Fourth arg is the field flags */
708
709	arg = arg->common.next;
710	info.field_flags = (u8) arg->common.value.integer;
711
712	/* Each remaining arg is a Named Field */
713
714	info.field_type = ACPI_TYPE_LOCAL_BANK_FIELD;
715	info.region_node = region_node;
716
717	/*
718	 * Use Info.data_register_node to store bank_field Op
719	 * It's safe because data_register_node will never be used when create bank field
720	 * We store aml_start and aml_length in the bank_field Op for late evaluation
721	 * Used in acpi_ex_prep_field_value(Info)
722	 *
723	 * TBD: Or, should we add a field in struct acpi_create_field_info, like "void *ParentOp"?
724	 */
725	info.data_register_node = (struct acpi_namespace_node *)op;
726
727	status = acpi_ds_get_field_names(&info, walk_state, arg->common.next);
728	return_ACPI_STATUS(status);
729}
730
731/*******************************************************************************
732 *
733 * FUNCTION:    acpi_ds_create_index_field
734 *
735 * PARAMETERS:  op              - Op containing the Field definition and args
736 *              region_node     - Object for the containing Operation Region
737 *  `           walk_state      - Current method state
738 *
739 * RETURN:      Status
740 *
741 * DESCRIPTION: Create a new index field in the specified operation region
742 *
743 ******************************************************************************/
744
745acpi_status
746acpi_ds_create_index_field(union acpi_parse_object *op,
747			   struct acpi_namespace_node *region_node,
748			   struct acpi_walk_state *walk_state)
749{
750	acpi_status status;
751	union acpi_parse_object *arg;
752	struct acpi_create_field_info info;
753
754	ACPI_FUNCTION_TRACE_PTR(ds_create_index_field, op);
755
756	/* First arg is the name of the Index register (must already exist) */
757
758	arg = op->common.value.arg;
759	status =
760	    acpi_ns_lookup(walk_state->scope_info, arg->common.value.string,
761			   ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
762			   ACPI_NS_SEARCH_PARENT, walk_state,
763			   &info.register_node);
764	if (ACPI_FAILURE(status)) {
765		ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
766		return_ACPI_STATUS(status);
767	}
768
769	/* Second arg is the data register (must already exist) */
770
771	arg = arg->common.next;
772	status =
773	    acpi_ns_lookup(walk_state->scope_info, arg->common.value.string,
774			   ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
775			   ACPI_NS_SEARCH_PARENT, walk_state,
776			   &info.data_register_node);
777	if (ACPI_FAILURE(status)) {
778		ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
779		return_ACPI_STATUS(status);
780	}
781
782	/* Next arg is the field flags */
783
784	arg = arg->common.next;
785	info.field_flags = (u8) arg->common.value.integer;
786
787	/* Each remaining arg is a Named Field */
788
789	info.field_type = ACPI_TYPE_LOCAL_INDEX_FIELD;
790	info.region_node = region_node;
791
792	status = acpi_ds_get_field_names(&info, walk_state, arg->common.next);
793	return_ACPI_STATUS(status);
794}
795