1 /******************************************************************************
3 * Module Name: psloop - Main AML parse loop
5 *****************************************************************************/
8 * Copyright (C) 2000 - 2006, R. Byron Moore
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
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.
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.
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.
45 * Parse the AML and build an operation tree as most interpreters,
46 * like Perl, do. Parsing is done by hand rather than with a YACC
47 * generated parser to tightly constrain stack and dynamic memory
48 * usage. At the same time, parsing is kept flexible and the code
49 * fairly compact by parsing based on a list of AML opcode
50 * templates in aml_op_info[]
53 #include <acpi/acpi.h>
54 #include <acpi/acparser.h>
55 #include <acpi/acdispat.h>
56 #include <acpi/amlcode.h>
58 #define _COMPONENT ACPI_PARSER
59 ACPI_MODULE_NAME("psloop")
61 static u32 acpi_gbl_depth = 0;
63 /*******************************************************************************
65 * FUNCTION: acpi_ps_parse_loop
67 * PARAMETERS: walk_state - Current state
71 * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
74 ******************************************************************************/
76 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
78 acpi_status status = AE_OK;
80 union acpi_parse_object *op = NULL; /* current op */
81 union acpi_parse_object *arg = NULL;
82 union acpi_parse_object *pre_op = NULL;
83 struct acpi_parse_state *parser_state;
84 u8 *aml_op_start = NULL;
86 ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);
88 if (walk_state->descending_callback == NULL) {
89 return_ACPI_STATUS(AE_BAD_PARAMETER);
92 parser_state = &walk_state->parser_state;
93 walk_state->arg_types = 0;
95 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
97 if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
99 /* We are restarting a preempted control method */
101 if (acpi_ps_has_completed_scope(parser_state)) {
103 * We must check if a predicate to an IF or WHILE statement
106 if ((parser_state->scope->parse_scope.op) &&
107 ((parser_state->scope->parse_scope.op->common.
108 aml_opcode == AML_IF_OP)
109 || (parser_state->scope->parse_scope.op->common.
110 aml_opcode == AML_WHILE_OP))
111 && (walk_state->control_state)
112 && (walk_state->control_state->common.state ==
113 ACPI_CONTROL_PREDICATE_EXECUTING)) {
115 * A predicate was just completed, get the value of the
116 * predicate and branch based on that value
118 walk_state->op = NULL;
120 acpi_ds_get_predicate_value(walk_state,
123 if (ACPI_FAILURE(status)
124 && ((status & AE_CODE_MASK) !=
126 if (status == AE_AML_NO_RETURN_VALUE) {
127 ACPI_EXCEPTION((AE_INFO, status,
128 "Invoked method did not return a value"));
131 ACPI_EXCEPTION((AE_INFO, status,
132 "GetPredicate Failed"));
133 return_ACPI_STATUS(status);
137 acpi_ps_next_parse_state(walk_state, op,
141 acpi_ps_pop_scope(parser_state, &op,
142 &walk_state->arg_types,
143 &walk_state->arg_count);
144 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
145 "Popped scope, Op=%p\n", op));
146 } else if (walk_state->prev_op) {
148 /* We were in the middle of an op */
150 op = walk_state->prev_op;
151 walk_state->arg_types = walk_state->prev_arg_types;
156 /* Iterative parsing loop, while there is more AML to process: */
158 while ((parser_state->aml < parser_state->aml_end) || (op)) {
159 aml_op_start = parser_state->aml;
162 /* Get the next opcode from the AML stream */
164 walk_state->aml_offset =
165 (u32) ACPI_PTR_DIFF(parser_state->aml,
166 parser_state->aml_start);
167 walk_state->opcode = acpi_ps_peek_opcode(parser_state);
170 * First cut to determine what we have found:
171 * 1) A valid AML opcode
173 * 3) An unknown/invalid opcode
175 walk_state->op_info =
176 acpi_ps_get_opcode_info(walk_state->opcode);
177 switch (walk_state->op_info->class) {
178 case AML_CLASS_ASCII:
179 case AML_CLASS_PREFIX:
181 * Starts with a valid prefix or ASCII char, this is a name
182 * string. Convert the bare name string to a namepath.
184 walk_state->opcode = AML_INT_NAMEPATH_OP;
185 walk_state->arg_types = ARGP_NAMESTRING;
188 case AML_CLASS_UNKNOWN:
190 /* The opcode is unrecognized. Just skip unknown opcodes */
193 "Found unknown opcode %X at AML address %p offset %X, ignoring",
196 walk_state->aml_offset));
198 ACPI_DUMP_BUFFER(parser_state->aml, 128);
200 /* Assume one-byte bad opcode */
207 /* Found opcode info, this is a normal opcode */
210 acpi_ps_get_opcode_size(walk_state->opcode);
211 walk_state->arg_types =
212 walk_state->op_info->parse_args;
216 /* Create Op structure and append to parent's argument list */
218 if (walk_state->op_info->flags & AML_NAMED) {
220 /* Allocate a new pre_op if necessary */
224 acpi_ps_alloc_op(walk_state->
227 status = AE_NO_MEMORY;
232 pre_op->common.value.arg = NULL;
233 pre_op->common.aml_opcode = walk_state->opcode;
236 * Get and append arguments until we find the node that contains
237 * the name (the type ARGP_NAME).
239 while (GET_CURRENT_ARG_TYPE
240 (walk_state->arg_types)
242 (GET_CURRENT_ARG_TYPE
243 (walk_state->arg_types) != ARGP_NAME)) {
245 acpi_ps_get_next_arg(walk_state,
251 if (ACPI_FAILURE(status)) {
255 acpi_ps_append_arg(pre_op, arg);
256 INCREMENT_ARG_LIST(walk_state->
261 * Make sure that we found a NAME and didn't run out of
264 if (!GET_CURRENT_ARG_TYPE
265 (walk_state->arg_types)) {
266 status = AE_AML_NO_OPERAND;
270 /* We know that this arg is a name, move to next arg */
272 INCREMENT_ARG_LIST(walk_state->arg_types);
275 * Find the object. This will either insert the object into
276 * the namespace or simply look it up
278 walk_state->op = NULL;
281 walk_state->descending_callback(walk_state,
283 if (ACPI_FAILURE(status)) {
284 ACPI_EXCEPTION((AE_INFO, status,
285 "During name lookup/catalog"));
294 acpi_ps_next_parse_state(walk_state, op,
296 if (status == AE_CTRL_PENDING) {
301 if (ACPI_FAILURE(status)) {
305 acpi_ps_append_arg(op,
306 pre_op->common.value.arg);
309 if (op->common.aml_opcode == AML_REGION_OP) {
311 * Defer final parsing of an operation_region body,
312 * because we don't have enough info in the first pass
313 * to parse it correctly (i.e., there may be method
314 * calls within the term_arg elements of the body.)
316 * However, we must continue parsing because
317 * the opregion is not a standalone package --
318 * we don't know where the end is at this point.
320 * (Length is unknown until parse of the body complete)
322 op->named.data = aml_op_start;
323 op->named.length = 0;
326 /* Not a named opcode, just allocate Op and append to parent */
328 walk_state->op_info =
329 acpi_ps_get_opcode_info(walk_state->opcode);
330 op = acpi_ps_alloc_op(walk_state->opcode);
332 status = AE_NO_MEMORY;
336 if (walk_state->op_info->flags & AML_CREATE) {
338 * Backup to beginning of create_xXXfield declaration
339 * body_length is unknown until we parse the body
341 op->named.data = aml_op_start;
342 op->named.length = 0;
345 acpi_ps_append_arg(acpi_ps_get_parent_scope
348 if ((walk_state->descending_callback != NULL)) {
350 * Find the object. This will either insert the object into
351 * the namespace or simply look it up
357 descending_callback(walk_state,
360 acpi_ps_next_parse_state(walk_state,
363 if (status == AE_CTRL_PENDING) {
368 if (ACPI_FAILURE(status)) {
374 op->common.aml_offset = walk_state->aml_offset;
376 if (walk_state->op_info) {
377 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
378 "Opcode %4.4X [%s] Op %p Aml %p AmlOffset %5.5X\n",
379 (u32) op->common.aml_opcode,
380 walk_state->op_info->name, op,
382 op->common.aml_offset));
387 * Start arg_count at zero because we don't know if there are
390 walk_state->arg_count = 0;
392 /* Are there any arguments that must be processed? */
394 if (walk_state->arg_types) {
398 switch (op->common.aml_opcode) {
399 case AML_BYTE_OP: /* AML_BYTEDATA_ARG */
400 case AML_WORD_OP: /* AML_WORDDATA_ARG */
401 case AML_DWORD_OP: /* AML_DWORDATA_ARG */
402 case AML_QWORD_OP: /* AML_QWORDATA_ARG */
403 case AML_STRING_OP: /* AML_ASCIICHARLIST_ARG */
405 /* Fill in constant or string argument directly */
407 acpi_ps_get_next_simple_arg(parser_state,
413 case AML_INT_NAMEPATH_OP: /* AML_NAMESTRING_ARG */
416 acpi_ps_get_next_namepath(walk_state,
419 if (ACPI_FAILURE(status)) {
423 walk_state->arg_types = 0;
428 * Op is not a constant or string, append each argument
431 while (GET_CURRENT_ARG_TYPE
432 (walk_state->arg_types)
433 && !walk_state->arg_count) {
434 walk_state->aml_offset = (u32)
435 ACPI_PTR_DIFF(parser_state->aml,
440 acpi_ps_get_next_arg(walk_state,
446 if (ACPI_FAILURE(status)) {
451 arg->common.aml_offset =
452 walk_state->aml_offset;
453 acpi_ps_append_arg(op, arg);
455 INCREMENT_ARG_LIST(walk_state->
459 /* Special processing for certain opcodes */
461 /* TBD (remove): Temporary mechanism to disable this code if needed */
463 #ifdef ACPI_ENABLE_MODULE_LEVEL_CODE
465 if ((walk_state->pass_number <=
466 ACPI_IMODE_LOAD_PASS1)
469 parse_flags & ACPI_PARSE_DISASSEMBLE) ==
472 * We want to skip If/Else/While constructs during Pass1
473 * because we want to actually conditionally execute the
476 * Except for disassembly, where we always want to
477 * walk the If/Else/While packages
479 switch (op->common.aml_opcode) {
484 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
485 "Pass1: Skipping an If/Else/While body\n"));
487 /* Skip body of if/else/while in pass 1 */
490 parser_state->pkg_end;
491 walk_state->arg_count = 0;
499 switch (op->common.aml_opcode) {
503 * Skip parsing of control method
504 * because we don't have enough info in the first pass
505 * to parse it correctly.
507 * Save the length and address of the body
509 op->named.data = parser_state->aml;
511 (u32) (parser_state->pkg_end -
514 /* Skip body of method */
517 parser_state->pkg_end;
518 walk_state->arg_count = 0;
523 case AML_VAR_PACKAGE_OP:
525 if ((op->common.parent) &&
526 (op->common.parent->common.
527 aml_opcode == AML_NAME_OP)
528 && (walk_state->pass_number <=
529 ACPI_IMODE_LOAD_PASS2)) {
531 * Skip parsing of Buffers and Packages
532 * because we don't have enough info in the first pass
533 * to parse them correctly.
535 op->named.data = aml_op_start;
537 (u32) (parser_state->
544 parser_state->pkg_end;
545 walk_state->arg_count = 0;
551 if (walk_state->control_state) {
552 walk_state->control_state->
553 control.package_end =
554 parser_state->pkg_end;
560 /* No action for all other opcodes */
567 /* Check for arguments that need to be processed */
569 if (walk_state->arg_count) {
571 * There are arguments (complex ones), push Op and
572 * prepare for argument
574 status = acpi_ps_push_scope(parser_state, op,
575 walk_state->arg_types,
576 walk_state->arg_count);
577 if (ACPI_FAILURE(status)) {
585 * All arguments have been processed -- Op is complete,
588 walk_state->op_info =
589 acpi_ps_get_opcode_info(op->common.aml_opcode);
590 if (walk_state->op_info->flags & AML_NAMED) {
591 if (acpi_gbl_depth) {
595 if (op->common.aml_opcode == AML_REGION_OP) {
597 * Skip parsing of control method or opregion body,
598 * because we don't have enough info in the first pass
599 * to parse them correctly.
601 * Completed parsing an op_region declaration, we now
605 (u32) (parser_state->aml - op->named.data);
609 if (walk_state->op_info->flags & AML_CREATE) {
611 * Backup to beginning of create_xXXfield declaration (1 for
614 * body_length is unknown until we parse the body
617 (u32) (parser_state->aml - op->named.data);
620 /* This op complete, notify the dispatcher */
622 if (walk_state->ascending_callback != NULL) {
624 walk_state->opcode = op->common.aml_opcode;
626 status = walk_state->ascending_callback(walk_state);
628 acpi_ps_next_parse_state(walk_state, op, status);
629 if (status == AE_CTRL_PENDING) {
637 * Finished one argument of the containing scope
639 parser_state->scope->parse_scope.arg_count--;
641 /* Finished with pre_op */
644 acpi_ps_free_op(pre_op);
648 /* Close this Op (will result in parse subtree deletion) */
650 status2 = acpi_ps_complete_this_op(walk_state, op);
651 if (ACPI_FAILURE(status2)) {
652 return_ACPI_STATUS(status2);
660 case AE_CTRL_TRANSFER:
662 /* We are about to transfer to a called method. */
664 walk_state->prev_op = op;
665 walk_state->prev_arg_types = walk_state->arg_types;
666 return_ACPI_STATUS(status);
670 acpi_ps_pop_scope(parser_state, &op,
671 &walk_state->arg_types,
672 &walk_state->arg_count);
676 walk_state->op_info =
677 acpi_ps_get_opcode_info(op->common.
679 walk_state->opcode = op->common.aml_opcode;
682 walk_state->ascending_callback(walk_state);
684 acpi_ps_next_parse_state(walk_state, op,
688 acpi_ps_complete_this_op(walk_state, op);
689 if (ACPI_FAILURE(status2)) {
690 return_ACPI_STATUS(status2);
698 case AE_CTRL_CONTINUE:
700 /* Pop off scopes until we find the While */
702 while (!op || (op->common.aml_opcode != AML_WHILE_OP)) {
703 acpi_ps_pop_scope(parser_state, &op,
704 &walk_state->arg_types,
705 &walk_state->arg_count);
707 if (op->common.aml_opcode != AML_WHILE_OP) {
709 acpi_ds_result_stack_pop
711 if (ACPI_FAILURE(status2)) {
712 return_ACPI_STATUS(status2);
717 /* Close this iteration of the While loop */
720 walk_state->op_info =
721 acpi_ps_get_opcode_info(op->common.aml_opcode);
722 walk_state->opcode = op->common.aml_opcode;
724 status = walk_state->ascending_callback(walk_state);
726 acpi_ps_next_parse_state(walk_state, op, status);
728 status2 = acpi_ps_complete_this_op(walk_state, op);
729 if (ACPI_FAILURE(status2)) {
730 return_ACPI_STATUS(status2);
737 case AE_CTRL_TERMINATE:
745 acpi_ps_complete_this_op(walk_state,
747 if (ACPI_FAILURE(status2)) {
748 return_ACPI_STATUS(status2);
752 acpi_ds_result_stack_pop
754 if (ACPI_FAILURE(status2)) {
755 return_ACPI_STATUS(status2);
758 acpi_ut_delete_generic_state
759 (acpi_ut_pop_generic_state
760 (&walk_state->control_state));
763 acpi_ps_pop_scope(parser_state, &op,
764 &walk_state->arg_types,
765 &walk_state->arg_count);
769 return_ACPI_STATUS(status);
771 default: /* All other non-AE_OK status */
776 acpi_ps_complete_this_op(walk_state,
778 if (ACPI_FAILURE(status2)) {
779 return_ACPI_STATUS(status2);
783 acpi_ps_pop_scope(parser_state, &op,
784 &walk_state->arg_types,
785 &walk_state->arg_count);
790 * TBD: Cleanup parse ops on error
794 acpi_ps_pop_scope(parser_state, &op,
795 &walk_state->arg_types,
796 &walk_state->arg_count);
799 walk_state->prev_op = op;
800 walk_state->prev_arg_types = walk_state->arg_types;
801 return_ACPI_STATUS(status);
804 /* This scope complete? */
806 if (acpi_ps_has_completed_scope(parser_state)) {
807 acpi_ps_pop_scope(parser_state, &op,
808 &walk_state->arg_types,
809 &walk_state->arg_count);
810 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
811 "Popped scope, Op=%p\n", op));
816 } /* while parser_state->Aml */
819 * Complete the last Op (if not completed), and clear the scope stack.
820 * It is easily possible to end an AML "package" with an unbounded number
821 * of open scopes (such as when several ASL blocks are closed with
822 * sequential closing braces). We want to terminate each one cleanly.
824 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "AML package complete at Op %p\n",
828 if (walk_state->ascending_callback != NULL) {
830 walk_state->op_info =
831 acpi_ps_get_opcode_info(op->common.
833 walk_state->opcode = op->common.aml_opcode;
836 walk_state->ascending_callback(walk_state);
838 acpi_ps_next_parse_state(walk_state, op,
840 if (status == AE_CTRL_PENDING) {
845 if (status == AE_CTRL_TERMINATE) {
852 acpi_ps_complete_this_op
861 acpi_ps_pop_scope(parser_state,
870 return_ACPI_STATUS(status);
873 else if (ACPI_FAILURE(status)) {
875 /* First error is most important */
878 acpi_ps_complete_this_op(walk_state,
880 return_ACPI_STATUS(status);
884 status2 = acpi_ps_complete_this_op(walk_state, op);
885 if (ACPI_FAILURE(status2)) {
886 return_ACPI_STATUS(status2);
890 acpi_ps_pop_scope(parser_state, &op, &walk_state->arg_types,
891 &walk_state->arg_count);
895 return_ACPI_STATUS(status);