1 /******************************************************************************
3 * Module Name: psloop - Main AML parse loop
5 *****************************************************************************/
8 * Copyright (C) 2000 - 2015, Intel Corp.
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12 * modification, are permitted provided that the following conditions
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17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
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20 * including a substantially similar Disclaimer requirement for further
21 * binary redistribution.
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23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
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
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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[].
52 #include <acpi/acpi.h>
59 #define _COMPONENT ACPI_PARSER
60 ACPI_MODULE_NAME("psloop")
62 /* Local prototypes */
64 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
65 u8 * aml_op_start, union acpi_parse_object *op);
68 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
69 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id);
71 /*******************************************************************************
73 * FUNCTION: acpi_ps_get_arguments
75 * PARAMETERS: walk_state - Current state
76 * aml_op_start - Op start in AML
81 * DESCRIPTION: Get arguments for passed Op.
83 ******************************************************************************/
86 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
87 u8 * aml_op_start, union acpi_parse_object *op)
89 acpi_status status = AE_OK;
90 union acpi_parse_object *arg = NULL;
91 const struct acpi_opcode_info *op_info;
93 ACPI_FUNCTION_TRACE_PTR(ps_get_arguments, walk_state);
95 switch (op->common.aml_opcode) {
96 case AML_BYTE_OP: /* AML_BYTEDATA_ARG */
97 case AML_WORD_OP: /* AML_WORDDATA_ARG */
98 case AML_DWORD_OP: /* AML_DWORDATA_ARG */
99 case AML_QWORD_OP: /* AML_QWORDATA_ARG */
100 case AML_STRING_OP: /* AML_ASCIICHARLIST_ARG */
102 /* Fill in constant or string argument directly */
104 acpi_ps_get_next_simple_arg(&(walk_state->parser_state),
105 GET_CURRENT_ARG_TYPE(walk_state->
110 case AML_INT_NAMEPATH_OP: /* AML_NAMESTRING_ARG */
113 acpi_ps_get_next_namepath(walk_state,
114 &(walk_state->parser_state), op,
116 if (ACPI_FAILURE(status)) {
117 return_ACPI_STATUS(status);
120 walk_state->arg_types = 0;
125 * Op is not a constant or string, append each argument to the Op
127 while (GET_CURRENT_ARG_TYPE(walk_state->arg_types)
128 && !walk_state->arg_count) {
129 walk_state->aml = walk_state->parser_state.aml;
132 acpi_ps_get_next_arg(walk_state,
133 &(walk_state->parser_state),
135 (walk_state->arg_types), &arg);
136 if (ACPI_FAILURE(status)) {
137 return_ACPI_STATUS(status);
141 acpi_ps_append_arg(op, arg);
144 INCREMENT_ARG_LIST(walk_state->arg_types);
148 * Handle executable code at "module-level". This refers to
149 * executable opcodes that appear outside of any control method.
151 if ((walk_state->pass_number <= ACPI_IMODE_LOAD_PASS2) &&
152 ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) == 0)) {
154 * We want to skip If/Else/While constructs during Pass1 because we
155 * want to actually conditionally execute the code during Pass2.
157 * Except for disassembly, where we always want to walk the
158 * If/Else/While packages
160 switch (op->common.aml_opcode) {
165 * Currently supported module-level opcodes are:
166 * IF/ELSE/WHILE. These appear to be the most common,
167 * and easiest to support since they open an AML
170 if (walk_state->pass_number ==
171 ACPI_IMODE_LOAD_PASS1) {
172 acpi_ps_link_module_code(op->common.
184 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
185 "Pass1: Skipping an If/Else/While body\n"));
187 /* Skip body of if/else/while in pass 1 */
189 walk_state->parser_state.aml =
190 walk_state->parser_state.pkg_end;
191 walk_state->arg_count = 0;
196 * Check for an unsupported executable opcode at module
197 * level. We must be in PASS1, the parent must be a SCOPE,
198 * The opcode class must be EXECUTE, and the opcode must
199 * not be an argument to another opcode.
201 if ((walk_state->pass_number ==
202 ACPI_IMODE_LOAD_PASS1)
203 && (op->common.parent->common.aml_opcode ==
206 acpi_ps_get_opcode_info(op->common.
208 if ((op_info->class ==
209 AML_CLASS_EXECUTE) && (!arg)) {
210 ACPI_WARNING((AE_INFO,
211 "Unsupported module-level executable opcode "
212 "0x%.2X at table offset 0x%.4X",
222 acpi_table_header))));
229 /* Special processing for certain opcodes */
231 switch (op->common.aml_opcode) {
234 * Skip parsing of control method because we don't have enough
235 * info in the first pass to parse it correctly.
237 * Save the length and address of the body
239 op->named.data = walk_state->parser_state.aml;
240 op->named.length = (u32)
241 (walk_state->parser_state.pkg_end -
242 walk_state->parser_state.aml);
244 /* Skip body of method */
246 walk_state->parser_state.aml =
247 walk_state->parser_state.pkg_end;
248 walk_state->arg_count = 0;
253 case AML_VAR_PACKAGE_OP:
255 if ((op->common.parent) &&
256 (op->common.parent->common.aml_opcode ==
258 && (walk_state->pass_number <=
259 ACPI_IMODE_LOAD_PASS2)) {
261 * Skip parsing of Buffers and Packages because we don't have
262 * enough info in the first pass to parse them correctly.
264 op->named.data = aml_op_start;
265 op->named.length = (u32)
266 (walk_state->parser_state.pkg_end -
271 walk_state->parser_state.aml =
272 walk_state->parser_state.pkg_end;
273 walk_state->arg_count = 0;
279 if (walk_state->control_state) {
280 walk_state->control_state->control.package_end =
281 walk_state->parser_state.pkg_end;
287 /* No action for all other opcodes */
295 return_ACPI_STATUS(AE_OK);
298 /*******************************************************************************
300 * FUNCTION: acpi_ps_link_module_code
302 * PARAMETERS: parent_op - Parent parser op
303 * aml_start - Pointer to the AML
304 * aml_length - Length of executable AML
305 * owner_id - owner_id of module level code
309 * DESCRIPTION: Wrap the module-level code with a method object and link the
310 * object to the global list. Note, the mutex field of the method
311 * object is used to link multiple module-level code objects.
313 ******************************************************************************/
316 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
317 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id)
319 union acpi_operand_object *prev;
320 union acpi_operand_object *next;
321 union acpi_operand_object *method_obj;
322 struct acpi_namespace_node *parent_node;
324 /* Get the tail of the list */
326 prev = next = acpi_gbl_module_code_list;
329 next = next->method.mutex;
333 * Insert the module level code into the list. Merge it if it is
334 * adjacent to the previous element.
337 ((prev->method.aml_start + prev->method.aml_length) != aml_start)) {
339 /* Create, initialize, and link a new temporary method object */
341 method_obj = acpi_ut_create_internal_object(ACPI_TYPE_METHOD);
346 if (parent_op->common.node) {
347 parent_node = parent_op->common.node;
349 parent_node = acpi_gbl_root_node;
352 method_obj->method.aml_start = aml_start;
353 method_obj->method.aml_length = aml_length;
354 method_obj->method.owner_id = owner_id;
355 method_obj->method.info_flags |= ACPI_METHOD_MODULE_LEVEL;
358 * Save the parent node in next_object. This is cheating, but we
359 * don't want to expand the method object.
361 method_obj->method.next_object =
362 ACPI_CAST_PTR(union acpi_operand_object, parent_node);
365 acpi_gbl_module_code_list = method_obj;
367 prev->method.mutex = method_obj;
370 prev->method.aml_length += aml_length;
374 /*******************************************************************************
376 * FUNCTION: acpi_ps_parse_loop
378 * PARAMETERS: walk_state - Current state
382 * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
385 ******************************************************************************/
387 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
389 acpi_status status = AE_OK;
390 union acpi_parse_object *op = NULL; /* current op */
391 struct acpi_parse_state *parser_state;
392 u8 *aml_op_start = NULL;
394 ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);
396 if (walk_state->descending_callback == NULL) {
397 return_ACPI_STATUS(AE_BAD_PARAMETER);
400 parser_state = &walk_state->parser_state;
401 walk_state->arg_types = 0;
403 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
405 if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
407 /* We are restarting a preempted control method */
409 if (acpi_ps_has_completed_scope(parser_state)) {
411 * We must check if a predicate to an IF or WHILE statement
414 if ((parser_state->scope->parse_scope.op) &&
415 ((parser_state->scope->parse_scope.op->common.
416 aml_opcode == AML_IF_OP)
417 || (parser_state->scope->parse_scope.op->common.
418 aml_opcode == AML_WHILE_OP))
419 && (walk_state->control_state)
420 && (walk_state->control_state->common.state ==
421 ACPI_CONTROL_PREDICATE_EXECUTING)) {
423 * A predicate was just completed, get the value of the
424 * predicate and branch based on that value
426 walk_state->op = NULL;
428 acpi_ds_get_predicate_value(walk_state,
431 if (ACPI_FAILURE(status)
432 && ((status & AE_CODE_MASK) !=
434 if (status == AE_AML_NO_RETURN_VALUE) {
435 ACPI_EXCEPTION((AE_INFO, status,
436 "Invoked method did not return a value"));
439 ACPI_EXCEPTION((AE_INFO, status,
440 "GetPredicate Failed"));
441 return_ACPI_STATUS(status);
445 acpi_ps_next_parse_state(walk_state, op,
449 acpi_ps_pop_scope(parser_state, &op,
450 &walk_state->arg_types,
451 &walk_state->arg_count);
452 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
453 "Popped scope, Op=%p\n", op));
454 } else if (walk_state->prev_op) {
456 /* We were in the middle of an op */
458 op = walk_state->prev_op;
459 walk_state->arg_types = walk_state->prev_arg_types;
464 /* Iterative parsing loop, while there is more AML to process: */
466 while ((parser_state->aml < parser_state->aml_end) || (op)) {
467 aml_op_start = parser_state->aml;
470 acpi_ps_create_op(walk_state, aml_op_start, &op);
471 if (ACPI_FAILURE(status)) {
472 if (status == AE_CTRL_PARSE_CONTINUE) {
476 if (status == AE_CTRL_PARSE_PENDING) {
480 if (status == AE_CTRL_TERMINATE) {
481 return_ACPI_STATUS(status);
485 acpi_ps_complete_op(walk_state, &op,
487 if (ACPI_FAILURE(status)) {
488 return_ACPI_STATUS(status);
494 acpi_ex_start_trace_opcode(op, walk_state);
498 * Start arg_count at zero because we don't know if there are
501 walk_state->arg_count = 0;
503 /* Are there any arguments that must be processed? */
505 if (walk_state->arg_types) {
510 acpi_ps_get_arguments(walk_state, aml_op_start, op);
511 if (ACPI_FAILURE(status)) {
513 acpi_ps_complete_op(walk_state, &op,
515 if (ACPI_FAILURE(status)) {
516 return_ACPI_STATUS(status);
523 /* Check for arguments that need to be processed */
525 if (walk_state->arg_count) {
527 * There are arguments (complex ones), push Op and
528 * prepare for argument
530 status = acpi_ps_push_scope(parser_state, op,
531 walk_state->arg_types,
532 walk_state->arg_count);
533 if (ACPI_FAILURE(status)) {
535 acpi_ps_complete_op(walk_state, &op,
537 if (ACPI_FAILURE(status)) {
538 return_ACPI_STATUS(status);
549 * All arguments have been processed -- Op is complete,
552 walk_state->op_info =
553 acpi_ps_get_opcode_info(op->common.aml_opcode);
554 if (walk_state->op_info->flags & AML_NAMED) {
555 if (op->common.aml_opcode == AML_REGION_OP ||
556 op->common.aml_opcode == AML_DATA_REGION_OP) {
558 * Skip parsing of control method or opregion body,
559 * because we don't have enough info in the first pass
560 * to parse them correctly.
562 * Completed parsing an op_region declaration, we now
566 (u32) (parser_state->aml - op->named.data);
570 if (walk_state->op_info->flags & AML_CREATE) {
572 * Backup to beginning of create_XXXfield declaration (1 for
575 * body_length is unknown until we parse the body
578 (u32) (parser_state->aml - op->named.data);
581 if (op->common.aml_opcode == AML_BANK_FIELD_OP) {
583 * Backup to beginning of bank_field declaration
585 * body_length is unknown until we parse the body
588 (u32) (parser_state->aml - op->named.data);
591 /* This op complete, notify the dispatcher */
593 if (walk_state->ascending_callback != NULL) {
595 walk_state->opcode = op->common.aml_opcode;
597 status = walk_state->ascending_callback(walk_state);
599 acpi_ps_next_parse_state(walk_state, op, status);
600 if (status == AE_CTRL_PENDING) {
605 status = acpi_ps_complete_op(walk_state, &op, status);
606 if (ACPI_FAILURE(status)) {
607 return_ACPI_STATUS(status);
610 } /* while parser_state->Aml */
612 status = acpi_ps_complete_final_op(walk_state, op, status);
613 return_ACPI_STATUS(status);