xref: /openbmc/linux/drivers/acpi/acpica/psloop.c (revision e5c86679)
1 /******************************************************************************
2  *
3  * Module Name: psloop - Main AML parse loop
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2017, 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 "acinterp.h"
55 #include "acparser.h"
56 #include "acdispat.h"
57 #include "amlcode.h"
58 
59 #define _COMPONENT          ACPI_PARSER
60 ACPI_MODULE_NAME("psloop")
61 
62 /* Local prototypes */
63 static acpi_status
64 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
65 		      u8 * aml_op_start, union acpi_parse_object *op);
66 
67 static void
68 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
69 			 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id);
70 
71 /*******************************************************************************
72  *
73  * FUNCTION:    acpi_ps_get_arguments
74  *
75  * PARAMETERS:  walk_state          - Current state
76  *              aml_op_start        - Op start in AML
77  *              op                  - Current Op
78  *
79  * RETURN:      Status
80  *
81  * DESCRIPTION: Get arguments for passed Op.
82  *
83  ******************************************************************************/
84 
85 static acpi_status
86 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
87 		      u8 * aml_op_start, union acpi_parse_object *op)
88 {
89 	acpi_status status = AE_OK;
90 	union acpi_parse_object *arg = NULL;
91 	const struct acpi_opcode_info *op_info;
92 
93 	ACPI_FUNCTION_TRACE_PTR(ps_get_arguments, walk_state);
94 
95 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
96 			  "Get arguments for opcode [%s]\n",
97 			  op->common.aml_op_name));
98 
99 	switch (op->common.aml_opcode) {
100 	case AML_BYTE_OP:	/* AML_BYTEDATA_ARG */
101 	case AML_WORD_OP:	/* AML_WORDDATA_ARG */
102 	case AML_DWORD_OP:	/* AML_DWORDATA_ARG */
103 	case AML_QWORD_OP:	/* AML_QWORDATA_ARG */
104 	case AML_STRING_OP:	/* AML_ASCIICHARLIST_ARG */
105 
106 		/* Fill in constant or string argument directly */
107 
108 		acpi_ps_get_next_simple_arg(&(walk_state->parser_state),
109 					    GET_CURRENT_ARG_TYPE(walk_state->
110 								 arg_types),
111 					    op);
112 		break;
113 
114 	case AML_INT_NAMEPATH_OP:	/* AML_NAMESTRING_ARG */
115 
116 		status = acpi_ps_get_next_namepath(walk_state,
117 						   &(walk_state->parser_state),
118 						   op,
119 						   ACPI_POSSIBLE_METHOD_CALL);
120 		if (ACPI_FAILURE(status)) {
121 			return_ACPI_STATUS(status);
122 		}
123 
124 		walk_state->arg_types = 0;
125 		break;
126 
127 	default:
128 		/*
129 		 * Op is not a constant or string, append each argument to the Op
130 		 */
131 		while (GET_CURRENT_ARG_TYPE(walk_state->arg_types) &&
132 		       !walk_state->arg_count) {
133 			walk_state->aml = walk_state->parser_state.aml;
134 
135 			status =
136 			    acpi_ps_get_next_arg(walk_state,
137 						 &(walk_state->parser_state),
138 						 GET_CURRENT_ARG_TYPE
139 						 (walk_state->arg_types), &arg);
140 			if (ACPI_FAILURE(status)) {
141 				return_ACPI_STATUS(status);
142 			}
143 
144 			if (arg) {
145 				acpi_ps_append_arg(op, arg);
146 			}
147 
148 			INCREMENT_ARG_LIST(walk_state->arg_types);
149 		}
150 
151 		/*
152 		 * Handle executable code at "module-level". This refers to
153 		 * executable opcodes that appear outside of any control method.
154 		 */
155 		if ((walk_state->pass_number <= ACPI_IMODE_LOAD_PASS2) &&
156 		    ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) == 0)) {
157 			/*
158 			 * We want to skip If/Else/While constructs during Pass1 because we
159 			 * want to actually conditionally execute the code during Pass2.
160 			 *
161 			 * Except for disassembly, where we always want to walk the
162 			 * If/Else/While packages
163 			 */
164 			switch (op->common.aml_opcode) {
165 			case AML_IF_OP:
166 			case AML_ELSE_OP:
167 			case AML_WHILE_OP:
168 				/*
169 				 * Currently supported module-level opcodes are:
170 				 * IF/ELSE/WHILE. These appear to be the most common,
171 				 * and easiest to support since they open an AML
172 				 * package.
173 				 */
174 				if (walk_state->pass_number ==
175 				    ACPI_IMODE_LOAD_PASS1) {
176 					acpi_ps_link_module_code(op->common.
177 								 parent,
178 								 aml_op_start,
179 								 (u32)
180 								 (walk_state->
181 								 parser_state.
182 								 pkg_end -
183 								 aml_op_start),
184 								 walk_state->
185 								 owner_id);
186 				}
187 
188 				ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
189 						  "Pass1: Skipping an If/Else/While body\n"));
190 
191 				/* Skip body of if/else/while in pass 1 */
192 
193 				walk_state->parser_state.aml =
194 				    walk_state->parser_state.pkg_end;
195 				walk_state->arg_count = 0;
196 				break;
197 
198 			default:
199 				/*
200 				 * Check for an unsupported executable opcode at module
201 				 * level. We must be in PASS1, the parent must be a SCOPE,
202 				 * The opcode class must be EXECUTE, and the opcode must
203 				 * not be an argument to another opcode.
204 				 */
205 				if ((walk_state->pass_number ==
206 				     ACPI_IMODE_LOAD_PASS1)
207 				    && (op->common.parent->common.aml_opcode ==
208 					AML_SCOPE_OP)) {
209 					op_info =
210 					    acpi_ps_get_opcode_info(op->common.
211 								    aml_opcode);
212 					if ((op_info->class ==
213 					     AML_CLASS_EXECUTE) && (!arg)) {
214 						ACPI_WARNING((AE_INFO,
215 							      "Unsupported module-level executable opcode "
216 							      "0x%.2X at table offset 0x%.4X",
217 							      op->common.
218 							      aml_opcode,
219 							      (u32)
220 							      (ACPI_PTR_DIFF
221 							       (aml_op_start,
222 								walk_state->
223 								parser_state.
224 								aml_start) +
225 							       sizeof(struct
226 								      acpi_table_header))));
227 					}
228 				}
229 				break;
230 			}
231 		}
232 
233 		/* Special processing for certain opcodes */
234 
235 		switch (op->common.aml_opcode) {
236 		case AML_METHOD_OP:
237 			/*
238 			 * Skip parsing of control method because we don't have enough
239 			 * info in the first pass to parse it correctly.
240 			 *
241 			 * Save the length and address of the body
242 			 */
243 			op->named.data = walk_state->parser_state.aml;
244 			op->named.length = (u32)
245 			    (walk_state->parser_state.pkg_end -
246 			     walk_state->parser_state.aml);
247 
248 			/* Skip body of method */
249 
250 			walk_state->parser_state.aml =
251 			    walk_state->parser_state.pkg_end;
252 			walk_state->arg_count = 0;
253 			break;
254 
255 		case AML_BUFFER_OP:
256 		case AML_PACKAGE_OP:
257 		case AML_VAR_PACKAGE_OP:
258 
259 			if ((op->common.parent) &&
260 			    (op->common.parent->common.aml_opcode ==
261 			     AML_NAME_OP)
262 			    && (walk_state->pass_number <=
263 				ACPI_IMODE_LOAD_PASS2)) {
264 				/*
265 				 * Skip parsing of Buffers and Packages because we don't have
266 				 * enough info in the first pass to parse them correctly.
267 				 */
268 				op->named.data = aml_op_start;
269 				op->named.length = (u32)
270 				    (walk_state->parser_state.pkg_end -
271 				     aml_op_start);
272 
273 				/* Skip body */
274 
275 				walk_state->parser_state.aml =
276 				    walk_state->parser_state.pkg_end;
277 				walk_state->arg_count = 0;
278 			}
279 			break;
280 
281 		case AML_WHILE_OP:
282 
283 			if (walk_state->control_state) {
284 				walk_state->control_state->control.package_end =
285 				    walk_state->parser_state.pkg_end;
286 			}
287 			break;
288 
289 		default:
290 
291 			/* No action for all other opcodes */
292 
293 			break;
294 		}
295 
296 		break;
297 	}
298 
299 	return_ACPI_STATUS(AE_OK);
300 }
301 
302 /*******************************************************************************
303  *
304  * FUNCTION:    acpi_ps_link_module_code
305  *
306  * PARAMETERS:  parent_op           - Parent parser op
307  *              aml_start           - Pointer to the AML
308  *              aml_length          - Length of executable AML
309  *              owner_id            - owner_id of module level code
310  *
311  * RETURN:      None.
312  *
313  * DESCRIPTION: Wrap the module-level code with a method object and link the
314  *              object to the global list. Note, the mutex field of the method
315  *              object is used to link multiple module-level code objects.
316  *
317  ******************************************************************************/
318 
319 static void
320 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
321 			 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id)
322 {
323 	union acpi_operand_object *prev;
324 	union acpi_operand_object *next;
325 	union acpi_operand_object *method_obj;
326 	struct acpi_namespace_node *parent_node;
327 
328 	ACPI_FUNCTION_TRACE(ps_link_module_code);
329 
330 	/* Get the tail of the list */
331 
332 	prev = next = acpi_gbl_module_code_list;
333 	while (next) {
334 		prev = next;
335 		next = next->method.mutex;
336 	}
337 
338 	/*
339 	 * Insert the module level code into the list. Merge it if it is
340 	 * adjacent to the previous element.
341 	 */
342 	if (!prev ||
343 	    ((prev->method.aml_start + prev->method.aml_length) != aml_start)) {
344 
345 		/* Create, initialize, and link a new temporary method object */
346 
347 		method_obj = acpi_ut_create_internal_object(ACPI_TYPE_METHOD);
348 		if (!method_obj) {
349 			return_VOID;
350 		}
351 
352 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
353 				  "Create/Link new code block: %p\n",
354 				  method_obj));
355 
356 		if (parent_op->common.node) {
357 			parent_node = parent_op->common.node;
358 		} else {
359 			parent_node = acpi_gbl_root_node;
360 		}
361 
362 		method_obj->method.aml_start = aml_start;
363 		method_obj->method.aml_length = aml_length;
364 		method_obj->method.owner_id = owner_id;
365 		method_obj->method.info_flags |= ACPI_METHOD_MODULE_LEVEL;
366 
367 		/*
368 		 * Save the parent node in next_object. This is cheating, but we
369 		 * don't want to expand the method object.
370 		 */
371 		method_obj->method.next_object =
372 		    ACPI_CAST_PTR(union acpi_operand_object, parent_node);
373 
374 		if (!prev) {
375 			acpi_gbl_module_code_list = method_obj;
376 		} else {
377 			prev->method.mutex = method_obj;
378 		}
379 	} else {
380 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
381 				  "Appending to existing code block: %p\n",
382 				  prev));
383 
384 		prev->method.aml_length += aml_length;
385 	}
386 
387 	return_VOID;
388 }
389 
390 /*******************************************************************************
391  *
392  * FUNCTION:    acpi_ps_parse_loop
393  *
394  * PARAMETERS:  walk_state          - Current state
395  *
396  * RETURN:      Status
397  *
398  * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
399  *              a tree of ops.
400  *
401  ******************************************************************************/
402 
403 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
404 {
405 	acpi_status status = AE_OK;
406 	union acpi_parse_object *op = NULL;	/* current op */
407 	struct acpi_parse_state *parser_state;
408 	u8 *aml_op_start = NULL;
409 
410 	ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);
411 
412 	if (walk_state->descending_callback == NULL) {
413 		return_ACPI_STATUS(AE_BAD_PARAMETER);
414 	}
415 
416 	parser_state = &walk_state->parser_state;
417 	walk_state->arg_types = 0;
418 
419 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
420 
421 	if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
422 
423 		/* We are restarting a preempted control method */
424 
425 		if (acpi_ps_has_completed_scope(parser_state)) {
426 			/*
427 			 * We must check if a predicate to an IF or WHILE statement
428 			 * was just completed
429 			 */
430 			if ((parser_state->scope->parse_scope.op) &&
431 			    ((parser_state->scope->parse_scope.op->common.
432 			      aml_opcode == AML_IF_OP)
433 			     || (parser_state->scope->parse_scope.op->common.
434 				 aml_opcode == AML_WHILE_OP))
435 			    && (walk_state->control_state)
436 			    && (walk_state->control_state->common.state ==
437 				ACPI_CONTROL_PREDICATE_EXECUTING)) {
438 				/*
439 				 * A predicate was just completed, get the value of the
440 				 * predicate and branch based on that value
441 				 */
442 				walk_state->op = NULL;
443 				status =
444 				    acpi_ds_get_predicate_value(walk_state,
445 								ACPI_TO_POINTER
446 								(TRUE));
447 				if (ACPI_FAILURE(status)
448 				    && ((status & AE_CODE_MASK) !=
449 					AE_CODE_CONTROL)) {
450 					if (status == AE_AML_NO_RETURN_VALUE) {
451 						ACPI_EXCEPTION((AE_INFO, status,
452 								"Invoked method did not return a value"));
453 					}
454 
455 					ACPI_EXCEPTION((AE_INFO, status,
456 							"GetPredicate Failed"));
457 					return_ACPI_STATUS(status);
458 				}
459 
460 				status =
461 				    acpi_ps_next_parse_state(walk_state, op,
462 							     status);
463 			}
464 
465 			acpi_ps_pop_scope(parser_state, &op,
466 					  &walk_state->arg_types,
467 					  &walk_state->arg_count);
468 			ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
469 					  "Popped scope, Op=%p\n", op));
470 		} else if (walk_state->prev_op) {
471 
472 			/* We were in the middle of an op */
473 
474 			op = walk_state->prev_op;
475 			walk_state->arg_types = walk_state->prev_arg_types;
476 		}
477 	}
478 #endif
479 
480 	/* Iterative parsing loop, while there is more AML to process: */
481 
482 	while ((parser_state->aml < parser_state->aml_end) || (op)) {
483 		aml_op_start = parser_state->aml;
484 		if (!op) {
485 			status =
486 			    acpi_ps_create_op(walk_state, aml_op_start, &op);
487 			if (ACPI_FAILURE(status)) {
488 				if (status == AE_CTRL_PARSE_CONTINUE) {
489 					continue;
490 				}
491 
492 				if (status == AE_CTRL_PARSE_PENDING) {
493 					status = AE_OK;
494 				}
495 
496 				if (status == AE_CTRL_TERMINATE) {
497 					return_ACPI_STATUS(status);
498 				}
499 
500 				status =
501 				    acpi_ps_complete_op(walk_state, &op,
502 							status);
503 				if (ACPI_FAILURE(status)) {
504 					return_ACPI_STATUS(status);
505 				}
506 
507 				continue;
508 			}
509 
510 			acpi_ex_start_trace_opcode(op, walk_state);
511 		}
512 
513 		/*
514 		 * Start arg_count at zero because we don't know if there are
515 		 * any args yet
516 		 */
517 		walk_state->arg_count = 0;
518 
519 		/* Are there any arguments that must be processed? */
520 
521 		if (walk_state->arg_types) {
522 
523 			/* Get arguments */
524 
525 			status =
526 			    acpi_ps_get_arguments(walk_state, aml_op_start, op);
527 			if (ACPI_FAILURE(status)) {
528 				status =
529 				    acpi_ps_complete_op(walk_state, &op,
530 							status);
531 				if (ACPI_FAILURE(status)) {
532 					return_ACPI_STATUS(status);
533 				}
534 
535 				continue;
536 			}
537 		}
538 
539 		/* Check for arguments that need to be processed */
540 
541 		if (walk_state->arg_count) {
542 			/*
543 			 * There are arguments (complex ones), push Op and
544 			 * prepare for argument
545 			 */
546 			status = acpi_ps_push_scope(parser_state, op,
547 						    walk_state->arg_types,
548 						    walk_state->arg_count);
549 			if (ACPI_FAILURE(status)) {
550 				status =
551 				    acpi_ps_complete_op(walk_state, &op,
552 							status);
553 				if (ACPI_FAILURE(status)) {
554 					return_ACPI_STATUS(status);
555 				}
556 
557 				continue;
558 			}
559 
560 			op = NULL;
561 			continue;
562 		}
563 
564 		/*
565 		 * All arguments have been processed -- Op is complete,
566 		 * prepare for next
567 		 */
568 		walk_state->op_info =
569 		    acpi_ps_get_opcode_info(op->common.aml_opcode);
570 		if (walk_state->op_info->flags & AML_NAMED) {
571 			if (op->common.aml_opcode == AML_REGION_OP ||
572 			    op->common.aml_opcode == AML_DATA_REGION_OP) {
573 				/*
574 				 * Skip parsing of control method or opregion body,
575 				 * because we don't have enough info in the first pass
576 				 * to parse them correctly.
577 				 *
578 				 * Completed parsing an op_region declaration, we now
579 				 * know the length.
580 				 */
581 				op->named.length =
582 				    (u32) (parser_state->aml - op->named.data);
583 			}
584 		}
585 
586 		if (walk_state->op_info->flags & AML_CREATE) {
587 			/*
588 			 * Backup to beginning of create_XXXfield declaration (1 for
589 			 * Opcode)
590 			 *
591 			 * body_length is unknown until we parse the body
592 			 */
593 			op->named.length =
594 			    (u32) (parser_state->aml - op->named.data);
595 		}
596 
597 		if (op->common.aml_opcode == AML_BANK_FIELD_OP) {
598 			/*
599 			 * Backup to beginning of bank_field declaration
600 			 *
601 			 * body_length is unknown until we parse the body
602 			 */
603 			op->named.length =
604 			    (u32) (parser_state->aml - op->named.data);
605 		}
606 
607 		/* This op complete, notify the dispatcher */
608 
609 		if (walk_state->ascending_callback != NULL) {
610 			walk_state->op = op;
611 			walk_state->opcode = op->common.aml_opcode;
612 
613 			status = walk_state->ascending_callback(walk_state);
614 			status =
615 			    acpi_ps_next_parse_state(walk_state, op, status);
616 			if (status == AE_CTRL_PENDING) {
617 				status = AE_OK;
618 			}
619 		}
620 
621 		status = acpi_ps_complete_op(walk_state, &op, status);
622 		if (ACPI_FAILURE(status)) {
623 			return_ACPI_STATUS(status);
624 		}
625 
626 	}			/* while parser_state->Aml */
627 
628 	status = acpi_ps_complete_final_op(walk_state, op, status);
629 	return_ACPI_STATUS(status);
630 }
631