1 /******************************************************************************
3 * Module Name: psloop - Main AML parse loop
5 *****************************************************************************/
8 * Copyright (C) 2000 - 2005, 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.
46 * Parse the AML and build an operation tree as most interpreters,
47 * like Perl, do. Parsing is done by hand rather than with a YACC
48 * generated parser to tightly constrain stack and dynamic memory
49 * usage. At the same time, parsing is kept flexible and the code
50 * fairly compact by parsing based on a list of AML opcode
51 * templates in aml_op_info[]
54 #include <acpi/acpi.h>
55 #include <acpi/acparser.h>
56 #include <acpi/acdispat.h>
57 #include <acpi/amlcode.h>
58 #include <acpi/acnamesp.h>
59 #include <acpi/acinterp.h>
61 #define _COMPONENT ACPI_PARSER
62 ACPI_MODULE_NAME ("psloop")
64 static u32 acpi_gbl_depth
= 0;
67 /*******************************************************************************
69 * FUNCTION: acpi_ps_parse_loop
71 * PARAMETERS: walk_state - Current state
75 * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
78 ******************************************************************************/
82 struct acpi_walk_state
*walk_state
)
84 acpi_status status
= AE_OK
;
86 union acpi_parse_object
*op
= NULL
; /* current op */
87 union acpi_parse_object
*arg
= NULL
;
88 union acpi_parse_object
*pre_op
= NULL
;
89 struct acpi_parse_state
*parser_state
;
90 u8
*aml_op_start
= NULL
;
93 ACPI_FUNCTION_TRACE_PTR ("ps_parse_loop", walk_state
);
95 if (walk_state
->descending_callback
== NULL
) {
96 return_ACPI_STATUS (AE_BAD_PARAMETER
);
99 parser_state
= &walk_state
->parser_state
;
100 walk_state
->arg_types
= 0;
102 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
104 if (walk_state
->walk_type
& ACPI_WALK_METHOD_RESTART
) {
105 /* We are restarting a preempted control method */
107 if (acpi_ps_has_completed_scope (parser_state
)) {
109 * We must check if a predicate to an IF or WHILE statement
112 if ((parser_state
->scope
->parse_scope
.op
) &&
113 ((parser_state
->scope
->parse_scope
.op
->common
.aml_opcode
== AML_IF_OP
) ||
114 (parser_state
->scope
->parse_scope
.op
->common
.aml_opcode
== AML_WHILE_OP
)) &&
115 (walk_state
->control_state
) &&
116 (walk_state
->control_state
->common
.state
==
117 ACPI_CONTROL_PREDICATE_EXECUTING
)) {
119 * A predicate was just completed, get the value of the
120 * predicate and branch based on that value
122 walk_state
->op
= NULL
;
123 status
= acpi_ds_get_predicate_value (walk_state
, ACPI_TO_POINTER (TRUE
));
124 if (ACPI_FAILURE (status
) &&
125 ((status
& AE_CODE_MASK
) != AE_CODE_CONTROL
)) {
126 if (status
== AE_AML_NO_RETURN_VALUE
) {
127 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR
,
128 "Invoked method did not return a value, %s\n",
129 acpi_format_exception (status
)));
132 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR
,
133 "get_predicate Failed, %s\n",
134 acpi_format_exception (status
)));
135 return_ACPI_STATUS (status
);
138 status
= acpi_ps_next_parse_state (walk_state
, op
, status
);
141 acpi_ps_pop_scope (parser_state
, &op
,
142 &walk_state
->arg_types
, &walk_state
->arg_count
);
143 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE
, "Popped scope, Op=%p\n", op
));
145 else if (walk_state
->prev_op
) {
146 /* We were in the middle of an op */
148 op
= walk_state
->prev_op
;
149 walk_state
->arg_types
= walk_state
->prev_arg_types
;
154 /* Iterative parsing loop, while there is more AML to process: */
156 while ((parser_state
->aml
< parser_state
->aml_end
) || (op
)) {
157 aml_op_start
= parser_state
->aml
;
159 /* Get the next opcode from the AML stream */
161 walk_state
->aml_offset
= (u32
) ACPI_PTR_DIFF (parser_state
->aml
,
162 parser_state
->aml_start
);
163 walk_state
->opcode
= acpi_ps_peek_opcode (parser_state
);
166 * First cut to determine what we have found:
167 * 1) A valid AML opcode
169 * 3) An unknown/invalid opcode
171 walk_state
->op_info
= acpi_ps_get_opcode_info (walk_state
->opcode
);
172 switch (walk_state
->op_info
->class) {
173 case AML_CLASS_ASCII
:
174 case AML_CLASS_PREFIX
:
176 * Starts with a valid prefix or ASCII char, this is a name
177 * string. Convert the bare name string to a namepath.
179 walk_state
->opcode
= AML_INT_NAMEPATH_OP
;
180 walk_state
->arg_types
= ARGP_NAMESTRING
;
183 case AML_CLASS_UNKNOWN
:
185 /* The opcode is unrecognized. Just skip unknown opcodes */
187 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR
,
188 "Found unknown opcode %X at AML address %p offset %X, ignoring\n",
189 walk_state
->opcode
, parser_state
->aml
, walk_state
->aml_offset
));
191 ACPI_DUMP_BUFFER (parser_state
->aml
, 128);
193 /* Assume one-byte bad opcode */
200 /* Found opcode info, this is a normal opcode */
202 parser_state
->aml
+= acpi_ps_get_opcode_size (walk_state
->opcode
);
203 walk_state
->arg_types
= walk_state
->op_info
->parse_args
;
207 /* Create Op structure and append to parent's argument list */
209 if (walk_state
->op_info
->flags
& AML_NAMED
) {
210 /* Allocate a new pre_op if necessary */
213 pre_op
= acpi_ps_alloc_op (walk_state
->opcode
);
215 status
= AE_NO_MEMORY
;
220 pre_op
->common
.value
.arg
= NULL
;
221 pre_op
->common
.aml_opcode
= walk_state
->opcode
;
224 * Get and append arguments until we find the node that contains
225 * the name (the type ARGP_NAME).
227 while (GET_CURRENT_ARG_TYPE (walk_state
->arg_types
) &&
228 (GET_CURRENT_ARG_TYPE (walk_state
->arg_types
) != ARGP_NAME
)) {
229 status
= acpi_ps_get_next_arg (walk_state
, parser_state
,
230 GET_CURRENT_ARG_TYPE (walk_state
->arg_types
), &arg
);
231 if (ACPI_FAILURE (status
)) {
235 acpi_ps_append_arg (pre_op
, arg
);
236 INCREMENT_ARG_LIST (walk_state
->arg_types
);
240 * Make sure that we found a NAME and didn't run out of
243 if (!GET_CURRENT_ARG_TYPE (walk_state
->arg_types
)) {
244 status
= AE_AML_NO_OPERAND
;
248 /* We know that this arg is a name, move to next arg */
250 INCREMENT_ARG_LIST (walk_state
->arg_types
);
253 * Find the object. This will either insert the object into
254 * the namespace or simply look it up
256 walk_state
->op
= NULL
;
258 status
= walk_state
->descending_callback (walk_state
, &op
);
259 if (ACPI_FAILURE (status
)) {
260 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR
,
261 "During name lookup/catalog, %s\n",
262 acpi_format_exception (status
)));
270 status
= acpi_ps_next_parse_state (walk_state
, op
, status
);
271 if (status
== AE_CTRL_PENDING
) {
276 if (ACPI_FAILURE (status
)) {
280 acpi_ps_append_arg (op
, pre_op
->common
.value
.arg
);
283 if (op
->common
.aml_opcode
== AML_REGION_OP
) {
285 * Defer final parsing of an operation_region body,
286 * because we don't have enough info in the first pass
287 * to parse it correctly (i.e., there may be method
288 * calls within the term_arg elements of the body.)
290 * However, we must continue parsing because
291 * the opregion is not a standalone package --
292 * we don't know where the end is at this point.
294 * (Length is unknown until parse of the body complete)
296 op
->named
.data
= aml_op_start
;
297 op
->named
.length
= 0;
301 /* Not a named opcode, just allocate Op and append to parent */
303 walk_state
->op_info
= acpi_ps_get_opcode_info (walk_state
->opcode
);
304 op
= acpi_ps_alloc_op (walk_state
->opcode
);
306 status
= AE_NO_MEMORY
;
310 if (walk_state
->op_info
->flags
& AML_CREATE
) {
312 * Backup to beginning of create_xXXfield declaration
313 * body_length is unknown until we parse the body
315 op
->named
.data
= aml_op_start
;
316 op
->named
.length
= 0;
319 acpi_ps_append_arg (acpi_ps_get_parent_scope (parser_state
), op
);
321 if ((walk_state
->descending_callback
!= NULL
)) {
323 * Find the object. This will either insert the object into
324 * the namespace or simply look it up
328 status
= walk_state
->descending_callback (walk_state
, &op
);
329 status
= acpi_ps_next_parse_state (walk_state
, op
, status
);
330 if (status
== AE_CTRL_PENDING
) {
335 if (ACPI_FAILURE (status
)) {
341 op
->common
.aml_offset
= walk_state
->aml_offset
;
343 if (walk_state
->op_info
) {
344 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE
,
345 "Opcode %4.4X [%s] Op %p Aml %p aml_offset %5.5X\n",
346 (u32
) op
->common
.aml_opcode
, walk_state
->op_info
->name
,
347 op
, parser_state
->aml
, op
->common
.aml_offset
));
353 * Start arg_count at zero because we don't know if there are
356 walk_state
->arg_count
= 0;
358 /* Are there any arguments that must be processed? */
360 if (walk_state
->arg_types
) {
363 switch (op
->common
.aml_opcode
) {
364 case AML_BYTE_OP
: /* AML_BYTEDATA_ARG */
365 case AML_WORD_OP
: /* AML_WORDDATA_ARG */
366 case AML_DWORD_OP
: /* AML_DWORDATA_ARG */
367 case AML_QWORD_OP
: /* AML_QWORDATA_ARG */
368 case AML_STRING_OP
: /* AML_ASCIICHARLIST_ARG */
370 /* Fill in constant or string argument directly */
372 acpi_ps_get_next_simple_arg (parser_state
,
373 GET_CURRENT_ARG_TYPE (walk_state
->arg_types
), op
);
376 case AML_INT_NAMEPATH_OP
: /* AML_NAMESTRING_ARG */
378 status
= acpi_ps_get_next_namepath (walk_state
, parser_state
, op
, 1);
379 if (ACPI_FAILURE (status
)) {
383 walk_state
->arg_types
= 0;
388 * Op is not a constant or string, append each argument
391 while (GET_CURRENT_ARG_TYPE (walk_state
->arg_types
) &&
392 !walk_state
->arg_count
) {
393 walk_state
->aml_offset
= (u32
)
394 ACPI_PTR_DIFF (parser_state
->aml
, parser_state
->aml_start
);
396 status
= acpi_ps_get_next_arg (walk_state
, parser_state
,
397 GET_CURRENT_ARG_TYPE (walk_state
->arg_types
),
399 if (ACPI_FAILURE (status
)) {
404 arg
->common
.aml_offset
= walk_state
->aml_offset
;
405 acpi_ps_append_arg (op
, arg
);
407 INCREMENT_ARG_LIST (walk_state
->arg_types
);
410 /* Special processing for certain opcodes */
412 if ((walk_state
->pass_number
<= ACPI_IMODE_LOAD_PASS1
) &&
413 ((walk_state
->parse_flags
& ACPI_PARSE_DISASSEMBLE
) == 0)) {
415 * We want to skip If/Else/While constructs during Pass1
416 * because we want to actually conditionally execute the
419 * Except for disassembly, where we always want to
420 * walk the If/Else/While packages
422 switch (op
->common
.aml_opcode
) {
427 /* Skip body of if/else/while in pass 1 */
429 parser_state
->aml
= parser_state
->pkg_end
;
430 walk_state
->arg_count
= 0;
438 switch (op
->common
.aml_opcode
) {
442 * Skip parsing of control method
443 * because we don't have enough info in the first pass
444 * to parse it correctly.
446 * Save the length and address of the body
448 op
->named
.data
= parser_state
->aml
;
449 op
->named
.length
= (u32
) (parser_state
->pkg_end
-
452 /* Skip body of method */
454 parser_state
->aml
= parser_state
->pkg_end
;
455 walk_state
->arg_count
= 0;
460 case AML_VAR_PACKAGE_OP
:
462 if ((op
->common
.parent
) &&
463 (op
->common
.parent
->common
.aml_opcode
== AML_NAME_OP
) &&
464 (walk_state
->pass_number
<= ACPI_IMODE_LOAD_PASS2
)) {
466 * Skip parsing of Buffers and Packages
467 * because we don't have enough info in the first pass
468 * to parse them correctly.
470 op
->named
.data
= aml_op_start
;
471 op
->named
.length
= (u32
) (parser_state
->pkg_end
-
476 parser_state
->aml
= parser_state
->pkg_end
;
477 walk_state
->arg_count
= 0;
483 if (walk_state
->control_state
) {
484 walk_state
->control_state
->control
.package_end
=
485 parser_state
->pkg_end
;
491 /* No action for all other opcodes */
498 /* Check for arguments that need to be processed */
500 if (walk_state
->arg_count
) {
502 * There are arguments (complex ones), push Op and
503 * prepare for argument
505 status
= acpi_ps_push_scope (parser_state
, op
,
506 walk_state
->arg_types
, walk_state
->arg_count
);
507 if (ACPI_FAILURE (status
)) {
515 * All arguments have been processed -- Op is complete,
518 walk_state
->op_info
= acpi_ps_get_opcode_info (op
->common
.aml_opcode
);
519 if (walk_state
->op_info
->flags
& AML_NAMED
) {
520 if (acpi_gbl_depth
) {
524 if (op
->common
.aml_opcode
== AML_REGION_OP
) {
526 * Skip parsing of control method or opregion body,
527 * because we don't have enough info in the first pass
528 * to parse them correctly.
530 * Completed parsing an op_region declaration, we now
533 op
->named
.length
= (u32
) (parser_state
->aml
- op
->named
.data
);
537 if (walk_state
->op_info
->flags
& AML_CREATE
) {
539 * Backup to beginning of create_xXXfield declaration (1 for
542 * body_length is unknown until we parse the body
544 op
->named
.length
= (u32
) (parser_state
->aml
- op
->named
.data
);
547 /* This op complete, notify the dispatcher */
549 if (walk_state
->ascending_callback
!= NULL
) {
551 walk_state
->opcode
= op
->common
.aml_opcode
;
553 status
= walk_state
->ascending_callback (walk_state
);
554 status
= acpi_ps_next_parse_state (walk_state
, op
, status
);
555 if (status
== AE_CTRL_PENDING
) {
564 * Finished one argument of the containing scope
566 parser_state
->scope
->parse_scope
.arg_count
--;
568 /* Finished with pre_op */
571 acpi_ps_free_op (pre_op
);
575 /* Close this Op (will result in parse subtree deletion) */
577 status2
= acpi_ps_complete_this_op (walk_state
, op
);
578 if (ACPI_FAILURE (status2
)) {
579 return_ACPI_STATUS (status2
);
588 case AE_CTRL_TRANSFER
:
590 /* We are about to transfer to a called method. */
592 walk_state
->prev_op
= op
;
593 walk_state
->prev_arg_types
= walk_state
->arg_types
;
594 return_ACPI_STATUS (status
);
599 acpi_ps_pop_scope (parser_state
, &op
,
600 &walk_state
->arg_types
, &walk_state
->arg_count
);
604 walk_state
->op_info
= acpi_ps_get_opcode_info (op
->common
.aml_opcode
);
605 walk_state
->opcode
= op
->common
.aml_opcode
;
607 status
= walk_state
->ascending_callback (walk_state
);
608 status
= acpi_ps_next_parse_state (walk_state
, op
, status
);
610 status2
= acpi_ps_complete_this_op (walk_state
, op
);
611 if (ACPI_FAILURE (status2
)) {
612 return_ACPI_STATUS (status2
);
621 case AE_CTRL_CONTINUE
:
623 /* Pop off scopes until we find the While */
625 while (!op
|| (op
->common
.aml_opcode
!= AML_WHILE_OP
)) {
626 acpi_ps_pop_scope (parser_state
, &op
,
627 &walk_state
->arg_types
, &walk_state
->arg_count
);
630 /* Close this iteration of the While loop */
633 walk_state
->op_info
= acpi_ps_get_opcode_info (op
->common
.aml_opcode
);
634 walk_state
->opcode
= op
->common
.aml_opcode
;
636 status
= walk_state
->ascending_callback (walk_state
);
637 status
= acpi_ps_next_parse_state (walk_state
, op
, status
);
639 status2
= acpi_ps_complete_this_op (walk_state
, op
);
640 if (ACPI_FAILURE (status2
)) {
641 return_ACPI_STATUS (status2
);
649 case AE_CTRL_TERMINATE
:
656 status2
= acpi_ps_complete_this_op (walk_state
, op
);
657 if (ACPI_FAILURE (status2
)) {
658 return_ACPI_STATUS (status2
);
661 acpi_ps_pop_scope (parser_state
, &op
,
662 &walk_state
->arg_types
, &walk_state
->arg_count
);
666 return_ACPI_STATUS (status
);
669 default: /* All other non-AE_OK status */
673 status2
= acpi_ps_complete_this_op (walk_state
, op
);
674 if (ACPI_FAILURE (status2
)) {
675 return_ACPI_STATUS (status2
);
678 acpi_ps_pop_scope (parser_state
, &op
,
679 &walk_state
->arg_types
, &walk_state
->arg_count
);
685 * TBD: Cleanup parse ops on error
689 acpi_ps_pop_scope (parser_state
, &op
,
690 &walk_state
->arg_types
, &walk_state
->arg_count
);
693 walk_state
->prev_op
= op
;
694 walk_state
->prev_arg_types
= walk_state
->arg_types
;
695 return_ACPI_STATUS (status
);
698 /* This scope complete? */
700 if (acpi_ps_has_completed_scope (parser_state
)) {
701 acpi_ps_pop_scope (parser_state
, &op
,
702 &walk_state
->arg_types
, &walk_state
->arg_count
);
703 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE
, "Popped scope, Op=%p\n", op
));
709 } /* while parser_state->Aml */
713 * Complete the last Op (if not completed), and clear the scope stack.
714 * It is easily possible to end an AML "package" with an unbounded number
715 * of open scopes (such as when several ASL blocks are closed with
716 * sequential closing braces). We want to terminate each one cleanly.
718 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE
, "AML package complete at Op %p\n", op
));
721 if (walk_state
->ascending_callback
!= NULL
) {
723 walk_state
->op_info
= acpi_ps_get_opcode_info (op
->common
.aml_opcode
);
724 walk_state
->opcode
= op
->common
.aml_opcode
;
726 status
= walk_state
->ascending_callback (walk_state
);
727 status
= acpi_ps_next_parse_state (walk_state
, op
, status
);
728 if (status
== AE_CTRL_PENDING
) {
733 if (status
== AE_CTRL_TERMINATE
) {
739 status2
= acpi_ps_complete_this_op (walk_state
, op
);
740 if (ACPI_FAILURE (status2
)) {
741 return_ACPI_STATUS (status2
);
745 acpi_ps_pop_scope (parser_state
, &op
,
746 &walk_state
->arg_types
, &walk_state
->arg_count
);
750 return_ACPI_STATUS (status
);
753 else if (ACPI_FAILURE (status
)) {
754 /* First error is most important */
756 (void) acpi_ps_complete_this_op (walk_state
, op
);
757 return_ACPI_STATUS (status
);
761 status2
= acpi_ps_complete_this_op (walk_state
, op
);
762 if (ACPI_FAILURE (status2
)) {
763 return_ACPI_STATUS (status2
);
767 acpi_ps_pop_scope (parser_state
, &op
, &walk_state
->arg_types
,
768 &walk_state
->arg_count
);
772 return_ACPI_STATUS (status
);