| blob | 3cf0687b99157b4b111f32154719a7ae76e16838 |
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3 *
4 * Module Name: psloop - Main AML parse loop
5 *
6 * Copyright (C) 2000 - 2020, Intel Corp.
7 *
8 *****************************************************************************/
10 /*
11 * Parse the AML and build an operation tree as most interpreters, (such as
12 * Perl) do. Parsing is done by hand rather than with a YACC generated parser
13 * to tightly constrain stack and dynamic memory usage. Parsing is kept
14 * flexible and the code fairly compact by parsing based on a list of AML
15 * opcode templates in aml_op_info[].
16 */
18 #include <acpi/acpi.h>
27 #define _COMPONENT ACPI_PARSER
30 /* Local prototypes */
31 static acpi_status
35 /*******************************************************************************
36 *
37 * FUNCTION: acpi_ps_get_arguments
38 *
39 * PARAMETERS: walk_state - Current state
40 * aml_op_start - Op start in AML
41 * op - Current Op
42 *
43 * RETURN: Status
44 *
45 * DESCRIPTION: Get arguments for passed Op.
46 *
47 ******************************************************************************/
49 static acpi_status
52 {
69 /* Fill in constant or string argument directly */
73 arg_types),
74 op);
81 op,
82 ACPI_POSSIBLE_METHOD_CALL);
85 }
91 /*
92 * Op is not a constant or string, append each argument to the Op
93 */
111 }
113 status =
116 GET_CURRENT_ARG_TYPE
120 }
124 }
127 }
134 /* Special processing for certain opcodes */
138 /*
139 * Skip parsing of control method because we don't have enough
140 * info in the first pass to parse it correctly.
141 *
142 * Save the length and address of the body
143 */
149 /* Skip body of method */
162 AML_NAME_OP)
164 ACPI_IMODE_LOAD_PASS2)) {
168 aml_op_start));
170 /*
171 * Skip parsing of Buffers and Packages because we don't have
172 * enough info in the first pass to parse them correctly.
173 */
177 aml_op_start);
179 /* Skip body */
184 }
192 }
197 /* No action for all other opcodes */
200 }
203 }
206 }
208 /*******************************************************************************
209 *
210 * FUNCTION: acpi_ps_parse_loop
211 *
212 * PARAMETERS: walk_state - Current state
213 *
214 * RETURN: Status
215 *
216 * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
217 * a tree of ops.
218 *
219 ******************************************************************************/
222 {
227 u8 opcode_length;
233 }
238 #ifndef ACPI_CONSTANT_EVAL_ONLY
242 /* We are restarting a preempted control method */
245 /*
246 * We must check if a predicate to an IF or WHILE statement
247 * was just completed
248 */
256 ACPI_CONTROL_PREDICATE_EXECUTING)) {
257 /*
258 * A predicate was just completed, get the value of the
259 * predicate and branch based on that value
260 */
262 status =
264 ACPI_TO_POINTER
268 AE_CODE_CONTROL)) {
272 }
277 }
279 status =
281 status);
282 }
291 /* We were in the middle of an op */
295 }
296 }
297 #endif
299 /* Iterative parsing loop, while there is more AML to process: */
306 status =
309 /*
310 * ACPI_PARSE_MODULE_LEVEL means that we are loading a table by
311 * executing it as a control method. However, if we encounter
312 * an error while loading the table, we need to keep trying to
313 * load the table rather than aborting the table load. Set the
314 * status to AE_OK to proceed with the table load.
315 */
321 }
324 }
328 }
332 }
334 status =
336 status);
339 }
341 (acpi_ps_get_opcode_info
343 /*
344 * If the scope/device op fails to parse, skip the body of
345 * the scope op because the parse failure indicates that
346 * the device may not exist.
347 */
348 ACPI_INFO(("Skipping parse of AML opcode: %s (0x%4.4X)", acpi_ps_get_opcode_name(walk_state->opcode), walk_state->opcode));
350 /*
351 * Determine the opcode length before skipping the opcode.
352 * An opcode can be 1 byte or 2 bytes in length.
353 */
356 AML_EXTENDED_OPCODE) {
358 }
363 acpi_ps_get_next_package_end
367 }
370 }
373 }
375 /*
376 * Start arg_count at zero because we don't know if there are
377 * any args yet
378 */
393 }
395 /* Are there any arguments that must be processed? */
399 /* Get arguments */
401 status =
404 status =
406 status);
409 }
415 /*
416 * If the if/while op fails to parse, we will skip parsing
417 * the body of the op.
418 */
423 acpi_ps_get_next_package_end
435 acpi_ps_get_next_package_end
439 }
442 }
445 }
446 }
448 /* Check for arguments that need to be processed */
455 /*
456 * There are arguments (complex ones), push Op and
457 * prepare for argument
458 */
463 status =
465 status);
468 }
471 }
475 }
477 /*
478 * All arguments have been processed -- Op is complete,
479 * prepare for next
480 */
486 /*
487 * Skip parsing of control method or opregion body,
488 * because we don't have enough info in the first pass
489 * to parse them correctly.
490 *
491 * Completed parsing an op_region declaration, we now
492 * know the length.
493 */
496 }
497 }
500 /*
501 * Backup to beginning of create_XXXfield declaration (1 for
502 * Opcode)
503 *
504 * body_length is unknown until we parse the body
505 */
508 }
511 /*
512 * Backup to beginning of bank_field declaration
513 *
514 * body_length is unknown until we parse the body
515 */
518 }
520 /* This op complete, notify the dispatcher */
527 status =
537 /*
538 * ACPI_PARSE_MODULE_LEVEL flag means that we
539 * are currently loading a table by executing
540 * it as a control method. However, if we
541 * encounter an error while loading the table,
542 * we need to keep trying to load the table
543 * rather than aborting the table load (setting
544 * the status to AE_OK continues the table
545 * load). If we get a failure at this point, it
546 * means that the dispatcher got an error while
547 * trying to execute the Op.
548 */
550 }
551 }
556 }
562 }