xref: /openbmc/linux/drivers/acpi/acpica/psloop.c (revision b6bec26c)
1 /******************************************************************************
2  *
3  * Module Name: psloop - Main AML parse loop
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2012, 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 /*
45  * Parse the AML and build an operation tree as most interpreters, (such as
46  * Perl) do. Parsing is done by hand rather than with a YACC generated parser
47  * to tightly constrain stack and dynamic memory usage. Parsing is kept
48  * flexible and the code fairly compact by parsing based on a list of AML
49  * opcode templates in aml_op_info[].
50  */
51 
52 #include <acpi/acpi.h>
53 #include "accommon.h"
54 #include "acparser.h"
55 #include "acdispat.h"
56 #include "amlcode.h"
57 
58 #define _COMPONENT          ACPI_PARSER
59 ACPI_MODULE_NAME("psloop")
60 
61 static u32 acpi_gbl_depth = 0;
62 
63 /* Local prototypes */
64 
65 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state);
66 
67 static acpi_status
68 acpi_ps_build_named_op(struct acpi_walk_state *walk_state,
69 		       u8 * aml_op_start,
70 		       union acpi_parse_object *unnamed_op,
71 		       union acpi_parse_object **op);
72 
73 static acpi_status
74 acpi_ps_create_op(struct acpi_walk_state *walk_state,
75 		  u8 * aml_op_start, union acpi_parse_object **new_op);
76 
77 static acpi_status
78 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
79 		      u8 * aml_op_start, union acpi_parse_object *op);
80 
81 static acpi_status
82 acpi_ps_complete_op(struct acpi_walk_state *walk_state,
83 		    union acpi_parse_object **op, acpi_status status);
84 
85 static acpi_status
86 acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
87 			  union acpi_parse_object *op, acpi_status status);
88 
89 static void
90 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
91 			 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id);
92 
93 /*******************************************************************************
94  *
95  * FUNCTION:    acpi_ps_get_aml_opcode
96  *
97  * PARAMETERS:  walk_state          - Current state
98  *
99  * RETURN:      Status
100  *
101  * DESCRIPTION: Extract the next AML opcode from the input stream.
102  *
103  ******************************************************************************/
104 
105 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state)
106 {
107 
108 	ACPI_FUNCTION_TRACE_PTR(ps_get_aml_opcode, walk_state);
109 
110 	walk_state->aml_offset =
111 	    (u32) ACPI_PTR_DIFF(walk_state->parser_state.aml,
112 				walk_state->parser_state.aml_start);
113 	walk_state->opcode = acpi_ps_peek_opcode(&(walk_state->parser_state));
114 
115 	/*
116 	 * First cut to determine what we have found:
117 	 * 1) A valid AML opcode
118 	 * 2) A name string
119 	 * 3) An unknown/invalid opcode
120 	 */
121 	walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
122 
123 	switch (walk_state->op_info->class) {
124 	case AML_CLASS_ASCII:
125 	case AML_CLASS_PREFIX:
126 		/*
127 		 * Starts with a valid prefix or ASCII char, this is a name
128 		 * string. Convert the bare name string to a namepath.
129 		 */
130 		walk_state->opcode = AML_INT_NAMEPATH_OP;
131 		walk_state->arg_types = ARGP_NAMESTRING;
132 		break;
133 
134 	case AML_CLASS_UNKNOWN:
135 
136 		/* The opcode is unrecognized. Complain and skip unknown opcodes */
137 
138 		if (walk_state->pass_number == 2) {
139 			ACPI_ERROR((AE_INFO,
140 				    "Unknown opcode 0x%.2X at table offset 0x%.4X, ignoring",
141 				    walk_state->opcode,
142 				    (u32)(walk_state->aml_offset +
143 					  sizeof(struct acpi_table_header))));
144 
145 			ACPI_DUMP_BUFFER(walk_state->parser_state.aml - 16, 48);
146 
147 #ifdef ACPI_ASL_COMPILER
148 			/*
149 			 * This is executed for the disassembler only. Output goes
150 			 * to the disassembled ASL output file.
151 			 */
152 			acpi_os_printf
153 			    ("/*\nError: Unknown opcode 0x%.2X at table offset 0x%.4X, context:\n",
154 			     walk_state->opcode,
155 			     (u32)(walk_state->aml_offset +
156 				   sizeof(struct acpi_table_header)));
157 
158 			/* Dump the context surrounding the invalid opcode */
159 
160 			acpi_ut_dump_buffer(((u8 *)walk_state->parser_state.
161 					     aml - 16), 48, DB_BYTE_DISPLAY,
162 					    walk_state->aml_offset +
163 					    sizeof(struct acpi_table_header) -
164 					    16);
165 			acpi_os_printf(" */\n");
166 #endif
167 		}
168 
169 		/* Increment past one-byte or two-byte opcode */
170 
171 		walk_state->parser_state.aml++;
172 		if (walk_state->opcode > 0xFF) {	/* Can only happen if first byte is 0x5B */
173 			walk_state->parser_state.aml++;
174 		}
175 
176 		return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
177 
178 	default:
179 
180 		/* Found opcode info, this is a normal opcode */
181 
182 		walk_state->parser_state.aml +=
183 		    acpi_ps_get_opcode_size(walk_state->opcode);
184 		walk_state->arg_types = walk_state->op_info->parse_args;
185 		break;
186 	}
187 
188 	return_ACPI_STATUS(AE_OK);
189 }
190 
191 /*******************************************************************************
192  *
193  * FUNCTION:    acpi_ps_build_named_op
194  *
195  * PARAMETERS:  walk_state          - Current state
196  *              aml_op_start        - Begin of named Op in AML
197  *              unnamed_op          - Early Op (not a named Op)
198  *              op                  - Returned Op
199  *
200  * RETURN:      Status
201  *
202  * DESCRIPTION: Parse a named Op
203  *
204  ******************************************************************************/
205 
206 static acpi_status
207 acpi_ps_build_named_op(struct acpi_walk_state *walk_state,
208 		       u8 * aml_op_start,
209 		       union acpi_parse_object *unnamed_op,
210 		       union acpi_parse_object **op)
211 {
212 	acpi_status status = AE_OK;
213 	union acpi_parse_object *arg = NULL;
214 
215 	ACPI_FUNCTION_TRACE_PTR(ps_build_named_op, walk_state);
216 
217 	unnamed_op->common.value.arg = NULL;
218 	unnamed_op->common.arg_list_length = 0;
219 	unnamed_op->common.aml_opcode = walk_state->opcode;
220 
221 	/*
222 	 * Get and append arguments until we find the node that contains
223 	 * the name (the type ARGP_NAME).
224 	 */
225 	while (GET_CURRENT_ARG_TYPE(walk_state->arg_types) &&
226 	       (GET_CURRENT_ARG_TYPE(walk_state->arg_types) != ARGP_NAME)) {
227 		status =
228 		    acpi_ps_get_next_arg(walk_state,
229 					 &(walk_state->parser_state),
230 					 GET_CURRENT_ARG_TYPE(walk_state->
231 							      arg_types), &arg);
232 		if (ACPI_FAILURE(status)) {
233 			return_ACPI_STATUS(status);
234 		}
235 
236 		acpi_ps_append_arg(unnamed_op, arg);
237 		INCREMENT_ARG_LIST(walk_state->arg_types);
238 	}
239 
240 	/*
241 	 * Make sure that we found a NAME and didn't run out of arguments
242 	 */
243 	if (!GET_CURRENT_ARG_TYPE(walk_state->arg_types)) {
244 		return_ACPI_STATUS(AE_AML_NO_OPERAND);
245 	}
246 
247 	/* We know that this arg is a name, move to next arg */
248 
249 	INCREMENT_ARG_LIST(walk_state->arg_types);
250 
251 	/*
252 	 * Find the object. This will either insert the object into
253 	 * the namespace or simply look it up
254 	 */
255 	walk_state->op = NULL;
256 
257 	status = walk_state->descending_callback(walk_state, op);
258 	if (ACPI_FAILURE(status)) {
259 		ACPI_EXCEPTION((AE_INFO, status, "During name lookup/catalog"));
260 		return_ACPI_STATUS(status);
261 	}
262 
263 	if (!*op) {
264 		return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
265 	}
266 
267 	status = acpi_ps_next_parse_state(walk_state, *op, status);
268 	if (ACPI_FAILURE(status)) {
269 		if (status == AE_CTRL_PENDING) {
270 			return_ACPI_STATUS(AE_CTRL_PARSE_PENDING);
271 		}
272 		return_ACPI_STATUS(status);
273 	}
274 
275 	acpi_ps_append_arg(*op, unnamed_op->common.value.arg);
276 	acpi_gbl_depth++;
277 
278 	if ((*op)->common.aml_opcode == AML_REGION_OP ||
279 	    (*op)->common.aml_opcode == AML_DATA_REGION_OP) {
280 		/*
281 		 * Defer final parsing of an operation_region body, because we don't
282 		 * have enough info in the first pass to parse it correctly (i.e.,
283 		 * there may be method calls within the term_arg elements of the body.)
284 		 *
285 		 * However, we must continue parsing because the opregion is not a
286 		 * standalone package -- we don't know where the end is at this point.
287 		 *
288 		 * (Length is unknown until parse of the body complete)
289 		 */
290 		(*op)->named.data = aml_op_start;
291 		(*op)->named.length = 0;
292 	}
293 
294 	return_ACPI_STATUS(AE_OK);
295 }
296 
297 /*******************************************************************************
298  *
299  * FUNCTION:    acpi_ps_create_op
300  *
301  * PARAMETERS:  walk_state          - Current state
302  *              aml_op_start        - Op start in AML
303  *              new_op              - Returned Op
304  *
305  * RETURN:      Status
306  *
307  * DESCRIPTION: Get Op from AML
308  *
309  ******************************************************************************/
310 
311 static acpi_status
312 acpi_ps_create_op(struct acpi_walk_state *walk_state,
313 		  u8 * aml_op_start, union acpi_parse_object **new_op)
314 {
315 	acpi_status status = AE_OK;
316 	union acpi_parse_object *op;
317 	union acpi_parse_object *named_op = NULL;
318 	union acpi_parse_object *parent_scope;
319 	u8 argument_count;
320 	const struct acpi_opcode_info *op_info;
321 
322 	ACPI_FUNCTION_TRACE_PTR(ps_create_op, walk_state);
323 
324 	status = acpi_ps_get_aml_opcode(walk_state);
325 	if (status == AE_CTRL_PARSE_CONTINUE) {
326 		return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
327 	}
328 
329 	/* Create Op structure and append to parent's argument list */
330 
331 	walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
332 	op = acpi_ps_alloc_op(walk_state->opcode);
333 	if (!op) {
334 		return_ACPI_STATUS(AE_NO_MEMORY);
335 	}
336 
337 	if (walk_state->op_info->flags & AML_NAMED) {
338 		status =
339 		    acpi_ps_build_named_op(walk_state, aml_op_start, op,
340 					   &named_op);
341 		acpi_ps_free_op(op);
342 		if (ACPI_FAILURE(status)) {
343 			return_ACPI_STATUS(status);
344 		}
345 
346 		*new_op = named_op;
347 		return_ACPI_STATUS(AE_OK);
348 	}
349 
350 	/* Not a named opcode, just allocate Op and append to parent */
351 
352 	if (walk_state->op_info->flags & AML_CREATE) {
353 		/*
354 		 * Backup to beginning of create_XXXfield declaration
355 		 * body_length is unknown until we parse the body
356 		 */
357 		op->named.data = aml_op_start;
358 		op->named.length = 0;
359 	}
360 
361 	if (walk_state->opcode == AML_BANK_FIELD_OP) {
362 		/*
363 		 * Backup to beginning of bank_field declaration
364 		 * body_length is unknown until we parse the body
365 		 */
366 		op->named.data = aml_op_start;
367 		op->named.length = 0;
368 	}
369 
370 	parent_scope = acpi_ps_get_parent_scope(&(walk_state->parser_state));
371 	acpi_ps_append_arg(parent_scope, op);
372 
373 	if (parent_scope) {
374 		op_info =
375 		    acpi_ps_get_opcode_info(parent_scope->common.aml_opcode);
376 		if (op_info->flags & AML_HAS_TARGET) {
377 			argument_count =
378 			    acpi_ps_get_argument_count(op_info->type);
379 			if (parent_scope->common.arg_list_length >
380 			    argument_count) {
381 				op->common.flags |= ACPI_PARSEOP_TARGET;
382 			}
383 		} else if (parent_scope->common.aml_opcode == AML_INCREMENT_OP) {
384 			op->common.flags |= ACPI_PARSEOP_TARGET;
385 		}
386 	}
387 
388 	if (walk_state->descending_callback != NULL) {
389 		/*
390 		 * Find the object. This will either insert the object into
391 		 * the namespace or simply look it up
392 		 */
393 		walk_state->op = *new_op = op;
394 
395 		status = walk_state->descending_callback(walk_state, &op);
396 		status = acpi_ps_next_parse_state(walk_state, op, status);
397 		if (status == AE_CTRL_PENDING) {
398 			status = AE_CTRL_PARSE_PENDING;
399 		}
400 	}
401 
402 	return_ACPI_STATUS(status);
403 }
404 
405 /*******************************************************************************
406  *
407  * FUNCTION:    acpi_ps_get_arguments
408  *
409  * PARAMETERS:  walk_state          - Current state
410  *              aml_op_start        - Op start in AML
411  *              op                  - Current Op
412  *
413  * RETURN:      Status
414  *
415  * DESCRIPTION: Get arguments for passed Op.
416  *
417  ******************************************************************************/
418 
419 static acpi_status
420 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
421 		      u8 * aml_op_start, union acpi_parse_object *op)
422 {
423 	acpi_status status = AE_OK;
424 	union acpi_parse_object *arg = NULL;
425 	const struct acpi_opcode_info *op_info;
426 
427 	ACPI_FUNCTION_TRACE_PTR(ps_get_arguments, walk_state);
428 
429 	switch (op->common.aml_opcode) {
430 	case AML_BYTE_OP:	/* AML_BYTEDATA_ARG */
431 	case AML_WORD_OP:	/* AML_WORDDATA_ARG */
432 	case AML_DWORD_OP:	/* AML_DWORDATA_ARG */
433 	case AML_QWORD_OP:	/* AML_QWORDATA_ARG */
434 	case AML_STRING_OP:	/* AML_ASCIICHARLIST_ARG */
435 
436 		/* Fill in constant or string argument directly */
437 
438 		acpi_ps_get_next_simple_arg(&(walk_state->parser_state),
439 					    GET_CURRENT_ARG_TYPE(walk_state->
440 								 arg_types),
441 					    op);
442 		break;
443 
444 	case AML_INT_NAMEPATH_OP:	/* AML_NAMESTRING_ARG */
445 
446 		status =
447 		    acpi_ps_get_next_namepath(walk_state,
448 					      &(walk_state->parser_state), op,
449 					      1);
450 		if (ACPI_FAILURE(status)) {
451 			return_ACPI_STATUS(status);
452 		}
453 
454 		walk_state->arg_types = 0;
455 		break;
456 
457 	default:
458 		/*
459 		 * Op is not a constant or string, append each argument to the Op
460 		 */
461 		while (GET_CURRENT_ARG_TYPE(walk_state->arg_types)
462 		       && !walk_state->arg_count) {
463 			walk_state->aml_offset =
464 			    (u32) ACPI_PTR_DIFF(walk_state->parser_state.aml,
465 						walk_state->parser_state.
466 						aml_start);
467 
468 			status =
469 			    acpi_ps_get_next_arg(walk_state,
470 						 &(walk_state->parser_state),
471 						 GET_CURRENT_ARG_TYPE
472 						 (walk_state->arg_types), &arg);
473 			if (ACPI_FAILURE(status)) {
474 				return_ACPI_STATUS(status);
475 			}
476 
477 			if (arg) {
478 				arg->common.aml_offset = walk_state->aml_offset;
479 				acpi_ps_append_arg(op, arg);
480 			}
481 
482 			INCREMENT_ARG_LIST(walk_state->arg_types);
483 		}
484 
485 		/*
486 		 * Handle executable code at "module-level". This refers to
487 		 * executable opcodes that appear outside of any control method.
488 		 */
489 		if ((walk_state->pass_number <= ACPI_IMODE_LOAD_PASS2) &&
490 		    ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) == 0)) {
491 			/*
492 			 * We want to skip If/Else/While constructs during Pass1 because we
493 			 * want to actually conditionally execute the code during Pass2.
494 			 *
495 			 * Except for disassembly, where we always want to walk the
496 			 * If/Else/While packages
497 			 */
498 			switch (op->common.aml_opcode) {
499 			case AML_IF_OP:
500 			case AML_ELSE_OP:
501 			case AML_WHILE_OP:
502 
503 				/*
504 				 * Currently supported module-level opcodes are:
505 				 * IF/ELSE/WHILE. These appear to be the most common,
506 				 * and easiest to support since they open an AML
507 				 * package.
508 				 */
509 				if (walk_state->pass_number ==
510 				    ACPI_IMODE_LOAD_PASS1) {
511 					acpi_ps_link_module_code(op->common.
512 								 parent,
513 								 aml_op_start,
514 								 (u32)
515 								 (walk_state->
516 								 parser_state.
517 								 pkg_end -
518 								 aml_op_start),
519 								 walk_state->
520 								 owner_id);
521 				}
522 
523 				ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
524 						  "Pass1: Skipping an If/Else/While body\n"));
525 
526 				/* Skip body of if/else/while in pass 1 */
527 
528 				walk_state->parser_state.aml =
529 				    walk_state->parser_state.pkg_end;
530 				walk_state->arg_count = 0;
531 				break;
532 
533 			default:
534 				/*
535 				 * Check for an unsupported executable opcode at module
536 				 * level. We must be in PASS1, the parent must be a SCOPE,
537 				 * The opcode class must be EXECUTE, and the opcode must
538 				 * not be an argument to another opcode.
539 				 */
540 				if ((walk_state->pass_number ==
541 				     ACPI_IMODE_LOAD_PASS1)
542 				    && (op->common.parent->common.aml_opcode ==
543 					AML_SCOPE_OP)) {
544 					op_info =
545 					    acpi_ps_get_opcode_info(op->common.
546 								    aml_opcode);
547 					if ((op_info->class ==
548 					     AML_CLASS_EXECUTE) && (!arg)) {
549 						ACPI_WARNING((AE_INFO,
550 							      "Unsupported module-level executable opcode "
551 							      "0x%.2X at table offset 0x%.4X",
552 							      op->common.
553 							      aml_opcode,
554 							      (u32)
555 							      (ACPI_PTR_DIFF
556 							       (aml_op_start,
557 								walk_state->
558 								parser_state.
559 								aml_start) +
560 							       sizeof(struct
561 								      acpi_table_header))));
562 					}
563 				}
564 				break;
565 			}
566 		}
567 
568 		/* Special processing for certain opcodes */
569 
570 		switch (op->common.aml_opcode) {
571 		case AML_METHOD_OP:
572 			/*
573 			 * Skip parsing of control method because we don't have enough
574 			 * info in the first pass to parse it correctly.
575 			 *
576 			 * Save the length and address of the body
577 			 */
578 			op->named.data = walk_state->parser_state.aml;
579 			op->named.length = (u32)
580 			    (walk_state->parser_state.pkg_end -
581 			     walk_state->parser_state.aml);
582 
583 			/* Skip body of method */
584 
585 			walk_state->parser_state.aml =
586 			    walk_state->parser_state.pkg_end;
587 			walk_state->arg_count = 0;
588 			break;
589 
590 		case AML_BUFFER_OP:
591 		case AML_PACKAGE_OP:
592 		case AML_VAR_PACKAGE_OP:
593 
594 			if ((op->common.parent) &&
595 			    (op->common.parent->common.aml_opcode ==
596 			     AML_NAME_OP)
597 			    && (walk_state->pass_number <=
598 				ACPI_IMODE_LOAD_PASS2)) {
599 				/*
600 				 * Skip parsing of Buffers and Packages because we don't have
601 				 * enough info in the first pass to parse them correctly.
602 				 */
603 				op->named.data = aml_op_start;
604 				op->named.length = (u32)
605 				    (walk_state->parser_state.pkg_end -
606 				     aml_op_start);
607 
608 				/* Skip body */
609 
610 				walk_state->parser_state.aml =
611 				    walk_state->parser_state.pkg_end;
612 				walk_state->arg_count = 0;
613 			}
614 			break;
615 
616 		case AML_WHILE_OP:
617 
618 			if (walk_state->control_state) {
619 				walk_state->control_state->control.package_end =
620 				    walk_state->parser_state.pkg_end;
621 			}
622 			break;
623 
624 		default:
625 
626 			/* No action for all other opcodes */
627 			break;
628 		}
629 
630 		break;
631 	}
632 
633 	return_ACPI_STATUS(AE_OK);
634 }
635 
636 /*******************************************************************************
637  *
638  * FUNCTION:    acpi_ps_link_module_code
639  *
640  * PARAMETERS:  parent_op           - Parent parser op
641  *              aml_start           - Pointer to the AML
642  *              aml_length          - Length of executable AML
643  *              owner_id            - owner_id of module level code
644  *
645  * RETURN:      None.
646  *
647  * DESCRIPTION: Wrap the module-level code with a method object and link the
648  *              object to the global list. Note, the mutex field of the method
649  *              object is used to link multiple module-level code objects.
650  *
651  ******************************************************************************/
652 
653 static void
654 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
655 			 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id)
656 {
657 	union acpi_operand_object *prev;
658 	union acpi_operand_object *next;
659 	union acpi_operand_object *method_obj;
660 	struct acpi_namespace_node *parent_node;
661 
662 	/* Get the tail of the list */
663 
664 	prev = next = acpi_gbl_module_code_list;
665 	while (next) {
666 		prev = next;
667 		next = next->method.mutex;
668 	}
669 
670 	/*
671 	 * Insert the module level code into the list. Merge it if it is
672 	 * adjacent to the previous element.
673 	 */
674 	if (!prev ||
675 	    ((prev->method.aml_start + prev->method.aml_length) != aml_start)) {
676 
677 		/* Create, initialize, and link a new temporary method object */
678 
679 		method_obj = acpi_ut_create_internal_object(ACPI_TYPE_METHOD);
680 		if (!method_obj) {
681 			return;
682 		}
683 
684 		if (parent_op->common.node) {
685 			parent_node = parent_op->common.node;
686 		} else {
687 			parent_node = acpi_gbl_root_node;
688 		}
689 
690 		method_obj->method.aml_start = aml_start;
691 		method_obj->method.aml_length = aml_length;
692 		method_obj->method.owner_id = owner_id;
693 		method_obj->method.info_flags |= ACPI_METHOD_MODULE_LEVEL;
694 
695 		/*
696 		 * Save the parent node in next_object. This is cheating, but we
697 		 * don't want to expand the method object.
698 		 */
699 		method_obj->method.next_object =
700 		    ACPI_CAST_PTR(union acpi_operand_object, parent_node);
701 
702 		if (!prev) {
703 			acpi_gbl_module_code_list = method_obj;
704 		} else {
705 			prev->method.mutex = method_obj;
706 		}
707 	} else {
708 		prev->method.aml_length += aml_length;
709 	}
710 }
711 
712 /*******************************************************************************
713  *
714  * FUNCTION:    acpi_ps_complete_op
715  *
716  * PARAMETERS:  walk_state          - Current state
717  *              op                  - Returned Op
718  *              status              - Parse status before complete Op
719  *
720  * RETURN:      Status
721  *
722  * DESCRIPTION: Complete Op
723  *
724  ******************************************************************************/
725 
726 static acpi_status
727 acpi_ps_complete_op(struct acpi_walk_state *walk_state,
728 		    union acpi_parse_object **op, acpi_status status)
729 {
730 	acpi_status status2;
731 
732 	ACPI_FUNCTION_TRACE_PTR(ps_complete_op, walk_state);
733 
734 	/*
735 	 * Finished one argument of the containing scope
736 	 */
737 	walk_state->parser_state.scope->parse_scope.arg_count--;
738 
739 	/* Close this Op (will result in parse subtree deletion) */
740 
741 	status2 = acpi_ps_complete_this_op(walk_state, *op);
742 	if (ACPI_FAILURE(status2)) {
743 		return_ACPI_STATUS(status2);
744 	}
745 
746 	*op = NULL;
747 
748 	switch (status) {
749 	case AE_OK:
750 		break;
751 
752 	case AE_CTRL_TRANSFER:
753 
754 		/* We are about to transfer to a called method */
755 
756 		walk_state->prev_op = NULL;
757 		walk_state->prev_arg_types = walk_state->arg_types;
758 		return_ACPI_STATUS(status);
759 
760 	case AE_CTRL_END:
761 
762 		acpi_ps_pop_scope(&(walk_state->parser_state), op,
763 				  &walk_state->arg_types,
764 				  &walk_state->arg_count);
765 
766 		if (*op) {
767 			walk_state->op = *op;
768 			walk_state->op_info =
769 			    acpi_ps_get_opcode_info((*op)->common.aml_opcode);
770 			walk_state->opcode = (*op)->common.aml_opcode;
771 
772 			status = walk_state->ascending_callback(walk_state);
773 			status =
774 			    acpi_ps_next_parse_state(walk_state, *op, status);
775 
776 			status2 = acpi_ps_complete_this_op(walk_state, *op);
777 			if (ACPI_FAILURE(status2)) {
778 				return_ACPI_STATUS(status2);
779 			}
780 		}
781 
782 		status = AE_OK;
783 		break;
784 
785 	case AE_CTRL_BREAK:
786 	case AE_CTRL_CONTINUE:
787 
788 		/* Pop off scopes until we find the While */
789 
790 		while (!(*op) || ((*op)->common.aml_opcode != AML_WHILE_OP)) {
791 			acpi_ps_pop_scope(&(walk_state->parser_state), op,
792 					  &walk_state->arg_types,
793 					  &walk_state->arg_count);
794 		}
795 
796 		/* Close this iteration of the While loop */
797 
798 		walk_state->op = *op;
799 		walk_state->op_info =
800 		    acpi_ps_get_opcode_info((*op)->common.aml_opcode);
801 		walk_state->opcode = (*op)->common.aml_opcode;
802 
803 		status = walk_state->ascending_callback(walk_state);
804 		status = acpi_ps_next_parse_state(walk_state, *op, status);
805 
806 		status2 = acpi_ps_complete_this_op(walk_state, *op);
807 		if (ACPI_FAILURE(status2)) {
808 			return_ACPI_STATUS(status2);
809 		}
810 
811 		status = AE_OK;
812 		break;
813 
814 	case AE_CTRL_TERMINATE:
815 
816 		/* Clean up */
817 		do {
818 			if (*op) {
819 				status2 =
820 				    acpi_ps_complete_this_op(walk_state, *op);
821 				if (ACPI_FAILURE(status2)) {
822 					return_ACPI_STATUS(status2);
823 				}
824 
825 				acpi_ut_delete_generic_state
826 				    (acpi_ut_pop_generic_state
827 				     (&walk_state->control_state));
828 			}
829 
830 			acpi_ps_pop_scope(&(walk_state->parser_state), op,
831 					  &walk_state->arg_types,
832 					  &walk_state->arg_count);
833 
834 		} while (*op);
835 
836 		return_ACPI_STATUS(AE_OK);
837 
838 	default:		/* All other non-AE_OK status */
839 
840 		do {
841 			if (*op) {
842 				status2 =
843 				    acpi_ps_complete_this_op(walk_state, *op);
844 				if (ACPI_FAILURE(status2)) {
845 					return_ACPI_STATUS(status2);
846 				}
847 			}
848 
849 			acpi_ps_pop_scope(&(walk_state->parser_state), op,
850 					  &walk_state->arg_types,
851 					  &walk_state->arg_count);
852 
853 		} while (*op);
854 
855 #if 0
856 		/*
857 		 * TBD: Cleanup parse ops on error
858 		 */
859 		if (*op == NULL) {
860 			acpi_ps_pop_scope(parser_state, op,
861 					  &walk_state->arg_types,
862 					  &walk_state->arg_count);
863 		}
864 #endif
865 		walk_state->prev_op = NULL;
866 		walk_state->prev_arg_types = walk_state->arg_types;
867 		return_ACPI_STATUS(status);
868 	}
869 
870 	/* This scope complete? */
871 
872 	if (acpi_ps_has_completed_scope(&(walk_state->parser_state))) {
873 		acpi_ps_pop_scope(&(walk_state->parser_state), op,
874 				  &walk_state->arg_types,
875 				  &walk_state->arg_count);
876 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Popped scope, Op=%p\n", *op));
877 	} else {
878 		*op = NULL;
879 	}
880 
881 	return_ACPI_STATUS(AE_OK);
882 }
883 
884 /*******************************************************************************
885  *
886  * FUNCTION:    acpi_ps_complete_final_op
887  *
888  * PARAMETERS:  walk_state          - Current state
889  *              op                  - Current Op
890  *              status              - Current parse status before complete last
891  *                                    Op
892  *
893  * RETURN:      Status
894  *
895  * DESCRIPTION: Complete last Op.
896  *
897  ******************************************************************************/
898 
899 static acpi_status
900 acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
901 			  union acpi_parse_object *op, acpi_status status)
902 {
903 	acpi_status status2;
904 
905 	ACPI_FUNCTION_TRACE_PTR(ps_complete_final_op, walk_state);
906 
907 	/*
908 	 * Complete the last Op (if not completed), and clear the scope stack.
909 	 * It is easily possible to end an AML "package" with an unbounded number
910 	 * of open scopes (such as when several ASL blocks are closed with
911 	 * sequential closing braces). We want to terminate each one cleanly.
912 	 */
913 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "AML package complete at Op %p\n",
914 			  op));
915 	do {
916 		if (op) {
917 			if (walk_state->ascending_callback != NULL) {
918 				walk_state->op = op;
919 				walk_state->op_info =
920 				    acpi_ps_get_opcode_info(op->common.
921 							    aml_opcode);
922 				walk_state->opcode = op->common.aml_opcode;
923 
924 				status =
925 				    walk_state->ascending_callback(walk_state);
926 				status =
927 				    acpi_ps_next_parse_state(walk_state, op,
928 							     status);
929 				if (status == AE_CTRL_PENDING) {
930 					status =
931 					    acpi_ps_complete_op(walk_state, &op,
932 								AE_OK);
933 					if (ACPI_FAILURE(status)) {
934 						return_ACPI_STATUS(status);
935 					}
936 				}
937 
938 				if (status == AE_CTRL_TERMINATE) {
939 					status = AE_OK;
940 
941 					/* Clean up */
942 					do {
943 						if (op) {
944 							status2 =
945 							    acpi_ps_complete_this_op
946 							    (walk_state, op);
947 							if (ACPI_FAILURE
948 							    (status2)) {
949 								return_ACPI_STATUS
950 								    (status2);
951 							}
952 						}
953 
954 						acpi_ps_pop_scope(&
955 								  (walk_state->
956 								   parser_state),
957 								  &op,
958 								  &walk_state->
959 								  arg_types,
960 								  &walk_state->
961 								  arg_count);
962 
963 					} while (op);
964 
965 					return_ACPI_STATUS(status);
966 				}
967 
968 				else if (ACPI_FAILURE(status)) {
969 
970 					/* First error is most important */
971 
972 					(void)
973 					    acpi_ps_complete_this_op(walk_state,
974 								     op);
975 					return_ACPI_STATUS(status);
976 				}
977 			}
978 
979 			status2 = acpi_ps_complete_this_op(walk_state, op);
980 			if (ACPI_FAILURE(status2)) {
981 				return_ACPI_STATUS(status2);
982 			}
983 		}
984 
985 		acpi_ps_pop_scope(&(walk_state->parser_state), &op,
986 				  &walk_state->arg_types,
987 				  &walk_state->arg_count);
988 
989 	} while (op);
990 
991 	return_ACPI_STATUS(status);
992 }
993 
994 /*******************************************************************************
995  *
996  * FUNCTION:    acpi_ps_parse_loop
997  *
998  * PARAMETERS:  walk_state          - Current state
999  *
1000  * RETURN:      Status
1001  *
1002  * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
1003  *              a tree of ops.
1004  *
1005  ******************************************************************************/
1006 
1007 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
1008 {
1009 	acpi_status status = AE_OK;
1010 	union acpi_parse_object *op = NULL;	/* current op */
1011 	struct acpi_parse_state *parser_state;
1012 	u8 *aml_op_start = NULL;
1013 
1014 	ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);
1015 
1016 	if (walk_state->descending_callback == NULL) {
1017 		return_ACPI_STATUS(AE_BAD_PARAMETER);
1018 	}
1019 
1020 	parser_state = &walk_state->parser_state;
1021 	walk_state->arg_types = 0;
1022 
1023 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
1024 
1025 	if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
1026 
1027 		/* We are restarting a preempted control method */
1028 
1029 		if (acpi_ps_has_completed_scope(parser_state)) {
1030 			/*
1031 			 * We must check if a predicate to an IF or WHILE statement
1032 			 * was just completed
1033 			 */
1034 			if ((parser_state->scope->parse_scope.op) &&
1035 			    ((parser_state->scope->parse_scope.op->common.
1036 			      aml_opcode == AML_IF_OP)
1037 			     || (parser_state->scope->parse_scope.op->common.
1038 				 aml_opcode == AML_WHILE_OP))
1039 			    && (walk_state->control_state)
1040 			    && (walk_state->control_state->common.state ==
1041 				ACPI_CONTROL_PREDICATE_EXECUTING)) {
1042 				/*
1043 				 * A predicate was just completed, get the value of the
1044 				 * predicate and branch based on that value
1045 				 */
1046 				walk_state->op = NULL;
1047 				status =
1048 				    acpi_ds_get_predicate_value(walk_state,
1049 								ACPI_TO_POINTER
1050 								(TRUE));
1051 				if (ACPI_FAILURE(status)
1052 				    && ((status & AE_CODE_MASK) !=
1053 					AE_CODE_CONTROL)) {
1054 					if (status == AE_AML_NO_RETURN_VALUE) {
1055 						ACPI_EXCEPTION((AE_INFO, status,
1056 								"Invoked method did not return a value"));
1057 					}
1058 
1059 					ACPI_EXCEPTION((AE_INFO, status,
1060 							"GetPredicate Failed"));
1061 					return_ACPI_STATUS(status);
1062 				}
1063 
1064 				status =
1065 				    acpi_ps_next_parse_state(walk_state, op,
1066 							     status);
1067 			}
1068 
1069 			acpi_ps_pop_scope(parser_state, &op,
1070 					  &walk_state->arg_types,
1071 					  &walk_state->arg_count);
1072 			ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
1073 					  "Popped scope, Op=%p\n", op));
1074 		} else if (walk_state->prev_op) {
1075 
1076 			/* We were in the middle of an op */
1077 
1078 			op = walk_state->prev_op;
1079 			walk_state->arg_types = walk_state->prev_arg_types;
1080 		}
1081 	}
1082 #endif
1083 
1084 	/* Iterative parsing loop, while there is more AML to process: */
1085 
1086 	while ((parser_state->aml < parser_state->aml_end) || (op)) {
1087 		aml_op_start = parser_state->aml;
1088 		if (!op) {
1089 			status =
1090 			    acpi_ps_create_op(walk_state, aml_op_start, &op);
1091 			if (ACPI_FAILURE(status)) {
1092 				if (status == AE_CTRL_PARSE_CONTINUE) {
1093 					continue;
1094 				}
1095 
1096 				if (status == AE_CTRL_PARSE_PENDING) {
1097 					status = AE_OK;
1098 				}
1099 
1100 				status =
1101 				    acpi_ps_complete_op(walk_state, &op,
1102 							status);
1103 				if (ACPI_FAILURE(status)) {
1104 					return_ACPI_STATUS(status);
1105 				}
1106 
1107 				continue;
1108 			}
1109 
1110 			op->common.aml_offset = walk_state->aml_offset;
1111 
1112 			if (walk_state->op_info) {
1113 				ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
1114 						  "Opcode %4.4X [%s] Op %p Aml %p AmlOffset %5.5X\n",
1115 						  (u32) op->common.aml_opcode,
1116 						  walk_state->op_info->name, op,
1117 						  parser_state->aml,
1118 						  op->common.aml_offset));
1119 			}
1120 		}
1121 
1122 		/*
1123 		 * Start arg_count at zero because we don't know if there are
1124 		 * any args yet
1125 		 */
1126 		walk_state->arg_count = 0;
1127 
1128 		/* Are there any arguments that must be processed? */
1129 
1130 		if (walk_state->arg_types) {
1131 
1132 			/* Get arguments */
1133 
1134 			status =
1135 			    acpi_ps_get_arguments(walk_state, aml_op_start, op);
1136 			if (ACPI_FAILURE(status)) {
1137 				status =
1138 				    acpi_ps_complete_op(walk_state, &op,
1139 							status);
1140 				if (ACPI_FAILURE(status)) {
1141 					return_ACPI_STATUS(status);
1142 				}
1143 
1144 				continue;
1145 			}
1146 		}
1147 
1148 		/* Check for arguments that need to be processed */
1149 
1150 		if (walk_state->arg_count) {
1151 			/*
1152 			 * There are arguments (complex ones), push Op and
1153 			 * prepare for argument
1154 			 */
1155 			status = acpi_ps_push_scope(parser_state, op,
1156 						    walk_state->arg_types,
1157 						    walk_state->arg_count);
1158 			if (ACPI_FAILURE(status)) {
1159 				status =
1160 				    acpi_ps_complete_op(walk_state, &op,
1161 							status);
1162 				if (ACPI_FAILURE(status)) {
1163 					return_ACPI_STATUS(status);
1164 				}
1165 
1166 				continue;
1167 			}
1168 
1169 			op = NULL;
1170 			continue;
1171 		}
1172 
1173 		/*
1174 		 * All arguments have been processed -- Op is complete,
1175 		 * prepare for next
1176 		 */
1177 		walk_state->op_info =
1178 		    acpi_ps_get_opcode_info(op->common.aml_opcode);
1179 		if (walk_state->op_info->flags & AML_NAMED) {
1180 			if (acpi_gbl_depth) {
1181 				acpi_gbl_depth--;
1182 			}
1183 
1184 			if (op->common.aml_opcode == AML_REGION_OP ||
1185 			    op->common.aml_opcode == AML_DATA_REGION_OP) {
1186 				/*
1187 				 * Skip parsing of control method or opregion body,
1188 				 * because we don't have enough info in the first pass
1189 				 * to parse them correctly.
1190 				 *
1191 				 * Completed parsing an op_region declaration, we now
1192 				 * know the length.
1193 				 */
1194 				op->named.length =
1195 				    (u32) (parser_state->aml - op->named.data);
1196 			}
1197 		}
1198 
1199 		if (walk_state->op_info->flags & AML_CREATE) {
1200 			/*
1201 			 * Backup to beginning of create_XXXfield declaration (1 for
1202 			 * Opcode)
1203 			 *
1204 			 * body_length is unknown until we parse the body
1205 			 */
1206 			op->named.length =
1207 			    (u32) (parser_state->aml - op->named.data);
1208 		}
1209 
1210 		if (op->common.aml_opcode == AML_BANK_FIELD_OP) {
1211 			/*
1212 			 * Backup to beginning of bank_field declaration
1213 			 *
1214 			 * body_length is unknown until we parse the body
1215 			 */
1216 			op->named.length =
1217 			    (u32) (parser_state->aml - op->named.data);
1218 		}
1219 
1220 		/* This op complete, notify the dispatcher */
1221 
1222 		if (walk_state->ascending_callback != NULL) {
1223 			walk_state->op = op;
1224 			walk_state->opcode = op->common.aml_opcode;
1225 
1226 			status = walk_state->ascending_callback(walk_state);
1227 			status =
1228 			    acpi_ps_next_parse_state(walk_state, op, status);
1229 			if (status == AE_CTRL_PENDING) {
1230 				status = AE_OK;
1231 			}
1232 		}
1233 
1234 		status = acpi_ps_complete_op(walk_state, &op, status);
1235 		if (ACPI_FAILURE(status)) {
1236 			return_ACPI_STATUS(status);
1237 		}
1238 
1239 	}			/* while parser_state->Aml */
1240 
1241 	status = acpi_ps_complete_final_op(walk_state, op, status);
1242 	return_ACPI_STATUS(status);
1243 }
1244