xref: /openbmc/linux/drivers/acpi/acpica/psloop.c (revision 12eb4683)
1 /******************************************************************************
2  *
3  * Module Name: psloop - Main AML parse loop
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2013, 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 /* Local prototypes */
62 static acpi_status
63 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
64 		      u8 * aml_op_start, union acpi_parse_object *op);
65 
66 static void
67 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
68 			 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id);
69 
70 /*******************************************************************************
71  *
72  * FUNCTION:    acpi_ps_get_arguments
73  *
74  * PARAMETERS:  walk_state          - Current state
75  *              aml_op_start        - Op start in AML
76  *              op                  - Current Op
77  *
78  * RETURN:      Status
79  *
80  * DESCRIPTION: Get arguments for passed Op.
81  *
82  ******************************************************************************/
83 
84 static acpi_status
85 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
86 		      u8 * aml_op_start, union acpi_parse_object *op)
87 {
88 	acpi_status status = AE_OK;
89 	union acpi_parse_object *arg = NULL;
90 	const struct acpi_opcode_info *op_info;
91 
92 	ACPI_FUNCTION_TRACE_PTR(ps_get_arguments, walk_state);
93 
94 	switch (op->common.aml_opcode) {
95 	case AML_BYTE_OP:	/* AML_BYTEDATA_ARG */
96 	case AML_WORD_OP:	/* AML_WORDDATA_ARG */
97 	case AML_DWORD_OP:	/* AML_DWORDATA_ARG */
98 	case AML_QWORD_OP:	/* AML_QWORDATA_ARG */
99 	case AML_STRING_OP:	/* AML_ASCIICHARLIST_ARG */
100 
101 		/* Fill in constant or string argument directly */
102 
103 		acpi_ps_get_next_simple_arg(&(walk_state->parser_state),
104 					    GET_CURRENT_ARG_TYPE(walk_state->
105 								 arg_types),
106 					    op);
107 		break;
108 
109 	case AML_INT_NAMEPATH_OP:	/* AML_NAMESTRING_ARG */
110 
111 		status =
112 		    acpi_ps_get_next_namepath(walk_state,
113 					      &(walk_state->parser_state), op,
114 					      1);
115 		if (ACPI_FAILURE(status)) {
116 			return_ACPI_STATUS(status);
117 		}
118 
119 		walk_state->arg_types = 0;
120 		break;
121 
122 	default:
123 		/*
124 		 * Op is not a constant or string, append each argument to the Op
125 		 */
126 		while (GET_CURRENT_ARG_TYPE(walk_state->arg_types)
127 		       && !walk_state->arg_count) {
128 			walk_state->aml_offset =
129 			    (u32) ACPI_PTR_DIFF(walk_state->parser_state.aml,
130 						walk_state->parser_state.
131 						aml_start);
132 
133 			status =
134 			    acpi_ps_get_next_arg(walk_state,
135 						 &(walk_state->parser_state),
136 						 GET_CURRENT_ARG_TYPE
137 						 (walk_state->arg_types), &arg);
138 			if (ACPI_FAILURE(status)) {
139 				return_ACPI_STATUS(status);
140 			}
141 
142 			if (arg) {
143 				arg->common.aml_offset = walk_state->aml_offset;
144 				acpi_ps_append_arg(op, arg);
145 			}
146 
147 			INCREMENT_ARG_LIST(walk_state->arg_types);
148 		}
149 
150 		/*
151 		 * Handle executable code at "module-level". This refers to
152 		 * executable opcodes that appear outside of any control method.
153 		 */
154 		if ((walk_state->pass_number <= ACPI_IMODE_LOAD_PASS2) &&
155 		    ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) == 0)) {
156 			/*
157 			 * We want to skip If/Else/While constructs during Pass1 because we
158 			 * want to actually conditionally execute the code during Pass2.
159 			 *
160 			 * Except for disassembly, where we always want to walk the
161 			 * If/Else/While packages
162 			 */
163 			switch (op->common.aml_opcode) {
164 			case AML_IF_OP:
165 			case AML_ELSE_OP:
166 			case AML_WHILE_OP:
167 				/*
168 				 * Currently supported module-level opcodes are:
169 				 * IF/ELSE/WHILE. These appear to be the most common,
170 				 * and easiest to support since they open an AML
171 				 * package.
172 				 */
173 				if (walk_state->pass_number ==
174 				    ACPI_IMODE_LOAD_PASS1) {
175 					acpi_ps_link_module_code(op->common.
176 								 parent,
177 								 aml_op_start,
178 								 (u32)
179 								 (walk_state->
180 								 parser_state.
181 								 pkg_end -
182 								 aml_op_start),
183 								 walk_state->
184 								 owner_id);
185 				}
186 
187 				ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
188 						  "Pass1: Skipping an If/Else/While body\n"));
189 
190 				/* Skip body of if/else/while in pass 1 */
191 
192 				walk_state->parser_state.aml =
193 				    walk_state->parser_state.pkg_end;
194 				walk_state->arg_count = 0;
195 				break;
196 
197 			default:
198 				/*
199 				 * Check for an unsupported executable opcode at module
200 				 * level. We must be in PASS1, the parent must be a SCOPE,
201 				 * The opcode class must be EXECUTE, and the opcode must
202 				 * not be an argument to another opcode.
203 				 */
204 				if ((walk_state->pass_number ==
205 				     ACPI_IMODE_LOAD_PASS1)
206 				    && (op->common.parent->common.aml_opcode ==
207 					AML_SCOPE_OP)) {
208 					op_info =
209 					    acpi_ps_get_opcode_info(op->common.
210 								    aml_opcode);
211 					if ((op_info->class ==
212 					     AML_CLASS_EXECUTE) && (!arg)) {
213 						ACPI_WARNING((AE_INFO,
214 							      "Unsupported module-level executable opcode "
215 							      "0x%.2X at table offset 0x%.4X",
216 							      op->common.
217 							      aml_opcode,
218 							      (u32)
219 							      (ACPI_PTR_DIFF
220 							       (aml_op_start,
221 								walk_state->
222 								parser_state.
223 								aml_start) +
224 							       sizeof(struct
225 								      acpi_table_header))));
226 					}
227 				}
228 				break;
229 			}
230 		}
231 
232 		/* Special processing for certain opcodes */
233 
234 		switch (op->common.aml_opcode) {
235 		case AML_METHOD_OP:
236 			/*
237 			 * Skip parsing of control method because we don't have enough
238 			 * info in the first pass to parse it correctly.
239 			 *
240 			 * Save the length and address of the body
241 			 */
242 			op->named.data = walk_state->parser_state.aml;
243 			op->named.length = (u32)
244 			    (walk_state->parser_state.pkg_end -
245 			     walk_state->parser_state.aml);
246 
247 			/* Skip body of method */
248 
249 			walk_state->parser_state.aml =
250 			    walk_state->parser_state.pkg_end;
251 			walk_state->arg_count = 0;
252 			break;
253 
254 		case AML_BUFFER_OP:
255 		case AML_PACKAGE_OP:
256 		case AML_VAR_PACKAGE_OP:
257 
258 			if ((op->common.parent) &&
259 			    (op->common.parent->common.aml_opcode ==
260 			     AML_NAME_OP)
261 			    && (walk_state->pass_number <=
262 				ACPI_IMODE_LOAD_PASS2)) {
263 				/*
264 				 * Skip parsing of Buffers and Packages because we don't have
265 				 * enough info in the first pass to parse them correctly.
266 				 */
267 				op->named.data = aml_op_start;
268 				op->named.length = (u32)
269 				    (walk_state->parser_state.pkg_end -
270 				     aml_op_start);
271 
272 				/* Skip body */
273 
274 				walk_state->parser_state.aml =
275 				    walk_state->parser_state.pkg_end;
276 				walk_state->arg_count = 0;
277 			}
278 			break;
279 
280 		case AML_WHILE_OP:
281 
282 			if (walk_state->control_state) {
283 				walk_state->control_state->control.package_end =
284 				    walk_state->parser_state.pkg_end;
285 			}
286 			break;
287 
288 		default:
289 
290 			/* No action for all other opcodes */
291 
292 			break;
293 		}
294 
295 		break;
296 	}
297 
298 	return_ACPI_STATUS(AE_OK);
299 }
300 
301 /*******************************************************************************
302  *
303  * FUNCTION:    acpi_ps_link_module_code
304  *
305  * PARAMETERS:  parent_op           - Parent parser op
306  *              aml_start           - Pointer to the AML
307  *              aml_length          - Length of executable AML
308  *              owner_id            - owner_id of module level code
309  *
310  * RETURN:      None.
311  *
312  * DESCRIPTION: Wrap the module-level code with a method object and link the
313  *              object to the global list. Note, the mutex field of the method
314  *              object is used to link multiple module-level code objects.
315  *
316  ******************************************************************************/
317 
318 static void
319 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
320 			 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id)
321 {
322 	union acpi_operand_object *prev;
323 	union acpi_operand_object *next;
324 	union acpi_operand_object *method_obj;
325 	struct acpi_namespace_node *parent_node;
326 
327 	/* Get the tail of the list */
328 
329 	prev = next = acpi_gbl_module_code_list;
330 	while (next) {
331 		prev = next;
332 		next = next->method.mutex;
333 	}
334 
335 	/*
336 	 * Insert the module level code into the list. Merge it if it is
337 	 * adjacent to the previous element.
338 	 */
339 	if (!prev ||
340 	    ((prev->method.aml_start + prev->method.aml_length) != aml_start)) {
341 
342 		/* Create, initialize, and link a new temporary method object */
343 
344 		method_obj = acpi_ut_create_internal_object(ACPI_TYPE_METHOD);
345 		if (!method_obj) {
346 			return;
347 		}
348 
349 		if (parent_op->common.node) {
350 			parent_node = parent_op->common.node;
351 		} else {
352 			parent_node = acpi_gbl_root_node;
353 		}
354 
355 		method_obj->method.aml_start = aml_start;
356 		method_obj->method.aml_length = aml_length;
357 		method_obj->method.owner_id = owner_id;
358 		method_obj->method.info_flags |= ACPI_METHOD_MODULE_LEVEL;
359 
360 		/*
361 		 * Save the parent node in next_object. This is cheating, but we
362 		 * don't want to expand the method object.
363 		 */
364 		method_obj->method.next_object =
365 		    ACPI_CAST_PTR(union acpi_operand_object, parent_node);
366 
367 		if (!prev) {
368 			acpi_gbl_module_code_list = method_obj;
369 		} else {
370 			prev->method.mutex = method_obj;
371 		}
372 	} else {
373 		prev->method.aml_length += aml_length;
374 	}
375 }
376 
377 /*******************************************************************************
378  *
379  * FUNCTION:    acpi_ps_parse_loop
380  *
381  * PARAMETERS:  walk_state          - Current state
382  *
383  * RETURN:      Status
384  *
385  * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
386  *              a tree of ops.
387  *
388  ******************************************************************************/
389 
390 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
391 {
392 	acpi_status status = AE_OK;
393 	union acpi_parse_object *op = NULL;	/* current op */
394 	struct acpi_parse_state *parser_state;
395 	u8 *aml_op_start = NULL;
396 
397 	ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);
398 
399 	if (walk_state->descending_callback == NULL) {
400 		return_ACPI_STATUS(AE_BAD_PARAMETER);
401 	}
402 
403 	parser_state = &walk_state->parser_state;
404 	walk_state->arg_types = 0;
405 
406 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
407 
408 	if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
409 
410 		/* We are restarting a preempted control method */
411 
412 		if (acpi_ps_has_completed_scope(parser_state)) {
413 			/*
414 			 * We must check if a predicate to an IF or WHILE statement
415 			 * was just completed
416 			 */
417 			if ((parser_state->scope->parse_scope.op) &&
418 			    ((parser_state->scope->parse_scope.op->common.
419 			      aml_opcode == AML_IF_OP)
420 			     || (parser_state->scope->parse_scope.op->common.
421 				 aml_opcode == AML_WHILE_OP))
422 			    && (walk_state->control_state)
423 			    && (walk_state->control_state->common.state ==
424 				ACPI_CONTROL_PREDICATE_EXECUTING)) {
425 				/*
426 				 * A predicate was just completed, get the value of the
427 				 * predicate and branch based on that value
428 				 */
429 				walk_state->op = NULL;
430 				status =
431 				    acpi_ds_get_predicate_value(walk_state,
432 								ACPI_TO_POINTER
433 								(TRUE));
434 				if (ACPI_FAILURE(status)
435 				    && ((status & AE_CODE_MASK) !=
436 					AE_CODE_CONTROL)) {
437 					if (status == AE_AML_NO_RETURN_VALUE) {
438 						ACPI_EXCEPTION((AE_INFO, status,
439 								"Invoked method did not return a value"));
440 					}
441 
442 					ACPI_EXCEPTION((AE_INFO, status,
443 							"GetPredicate Failed"));
444 					return_ACPI_STATUS(status);
445 				}
446 
447 				status =
448 				    acpi_ps_next_parse_state(walk_state, op,
449 							     status);
450 			}
451 
452 			acpi_ps_pop_scope(parser_state, &op,
453 					  &walk_state->arg_types,
454 					  &walk_state->arg_count);
455 			ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
456 					  "Popped scope, Op=%p\n", op));
457 		} else if (walk_state->prev_op) {
458 
459 			/* We were in the middle of an op */
460 
461 			op = walk_state->prev_op;
462 			walk_state->arg_types = walk_state->prev_arg_types;
463 		}
464 	}
465 #endif
466 
467 	/* Iterative parsing loop, while there is more AML to process: */
468 
469 	while ((parser_state->aml < parser_state->aml_end) || (op)) {
470 		aml_op_start = parser_state->aml;
471 		if (!op) {
472 			status =
473 			    acpi_ps_create_op(walk_state, aml_op_start, &op);
474 			if (ACPI_FAILURE(status)) {
475 				if (status == AE_CTRL_PARSE_CONTINUE) {
476 					continue;
477 				}
478 
479 				if (status == AE_CTRL_PARSE_PENDING) {
480 					status = AE_OK;
481 				}
482 
483 				status =
484 				    acpi_ps_complete_op(walk_state, &op,
485 							status);
486 				if (ACPI_FAILURE(status)) {
487 					return_ACPI_STATUS(status);
488 				}
489 
490 				continue;
491 			}
492 
493 			op->common.aml_offset = walk_state->aml_offset;
494 
495 			if (walk_state->op_info) {
496 				ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
497 						  "Opcode %4.4X [%s] Op %p Aml %p AmlOffset %5.5X\n",
498 						  (u32) op->common.aml_opcode,
499 						  walk_state->op_info->name, op,
500 						  parser_state->aml,
501 						  op->common.aml_offset));
502 			}
503 		}
504 
505 		/*
506 		 * Start arg_count at zero because we don't know if there are
507 		 * any args yet
508 		 */
509 		walk_state->arg_count = 0;
510 
511 		/* Are there any arguments that must be processed? */
512 
513 		if (walk_state->arg_types) {
514 
515 			/* Get arguments */
516 
517 			status =
518 			    acpi_ps_get_arguments(walk_state, aml_op_start, op);
519 			if (ACPI_FAILURE(status)) {
520 				status =
521 				    acpi_ps_complete_op(walk_state, &op,
522 							status);
523 				if (ACPI_FAILURE(status)) {
524 					return_ACPI_STATUS(status);
525 				}
526 
527 				continue;
528 			}
529 		}
530 
531 		/* Check for arguments that need to be processed */
532 
533 		if (walk_state->arg_count) {
534 			/*
535 			 * There are arguments (complex ones), push Op and
536 			 * prepare for argument
537 			 */
538 			status = acpi_ps_push_scope(parser_state, op,
539 						    walk_state->arg_types,
540 						    walk_state->arg_count);
541 			if (ACPI_FAILURE(status)) {
542 				status =
543 				    acpi_ps_complete_op(walk_state, &op,
544 							status);
545 				if (ACPI_FAILURE(status)) {
546 					return_ACPI_STATUS(status);
547 				}
548 
549 				continue;
550 			}
551 
552 			op = NULL;
553 			continue;
554 		}
555 
556 		/*
557 		 * All arguments have been processed -- Op is complete,
558 		 * prepare for next
559 		 */
560 		walk_state->op_info =
561 		    acpi_ps_get_opcode_info(op->common.aml_opcode);
562 		if (walk_state->op_info->flags & AML_NAMED) {
563 			if (op->common.aml_opcode == AML_REGION_OP ||
564 			    op->common.aml_opcode == AML_DATA_REGION_OP) {
565 				/*
566 				 * Skip parsing of control method or opregion body,
567 				 * because we don't have enough info in the first pass
568 				 * to parse them correctly.
569 				 *
570 				 * Completed parsing an op_region declaration, we now
571 				 * know the length.
572 				 */
573 				op->named.length =
574 				    (u32) (parser_state->aml - op->named.data);
575 			}
576 		}
577 
578 		if (walk_state->op_info->flags & AML_CREATE) {
579 			/*
580 			 * Backup to beginning of create_XXXfield declaration (1 for
581 			 * Opcode)
582 			 *
583 			 * body_length is unknown until we parse the body
584 			 */
585 			op->named.length =
586 			    (u32) (parser_state->aml - op->named.data);
587 		}
588 
589 		if (op->common.aml_opcode == AML_BANK_FIELD_OP) {
590 			/*
591 			 * Backup to beginning of bank_field declaration
592 			 *
593 			 * body_length is unknown until we parse the body
594 			 */
595 			op->named.length =
596 			    (u32) (parser_state->aml - op->named.data);
597 		}
598 
599 		/* This op complete, notify the dispatcher */
600 
601 		if (walk_state->ascending_callback != NULL) {
602 			walk_state->op = op;
603 			walk_state->opcode = op->common.aml_opcode;
604 
605 			status = walk_state->ascending_callback(walk_state);
606 			status =
607 			    acpi_ps_next_parse_state(walk_state, op, status);
608 			if (status == AE_CTRL_PENDING) {
609 				status = AE_OK;
610 			}
611 		}
612 
613 		status = acpi_ps_complete_op(walk_state, &op, status);
614 		if (ACPI_FAILURE(status)) {
615 			return_ACPI_STATUS(status);
616 		}
617 
618 	}			/* while parser_state->Aml */
619 
620 	status = acpi_ps_complete_final_op(walk_state, op, status);
621 	return_ACPI_STATUS(status);
622 }
623