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);
411 /* Special processing for certain opcodes */
413 #define ACPI_NO_MODULE_LEVEL_CODE
415 /* TBD (remove): Temporary mechanism to disable this code if needed */
417 #ifndef ACPI_NO_MODULE_LEVEL_CODE
419 if ((walk_state->pass_number <= ACPI_IMODE_LOAD_PASS1) &&
420 ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) == 0)) {
422 * We want to skip If/Else/While constructs during Pass1
423 * because we want to actually conditionally execute the
426 * Except for disassembly, where we always want to
427 * walk the If/Else/While packages
429 switch (op->common.aml_opcode) {
434 /* Skip body of if/else/while in pass 1 */
436 parser_state->aml = parser_state->pkg_end;
437 walk_state->arg_count = 0;
445 switch (op->common.aml_opcode) {
449 * Skip parsing of control method
450 * because we don't have enough info in the first pass
451 * to parse it correctly.
453 * Save the length and address of the body
455 op->named.data = parser_state->aml;
456 op->named.length = (u32) (parser_state->pkg_end -
459 /* Skip body of method */
461 parser_state->aml = parser_state->pkg_end;
462 walk_state->arg_count = 0;
467 case AML_VAR_PACKAGE_OP:
469 if ((op->common.parent) &&
470 (op->common.parent->common.aml_opcode == AML_NAME_OP) &&
471 (walk_state->pass_number <= ACPI_IMODE_LOAD_PASS2)) {
473 * Skip parsing of Buffers and Packages
474 * because we don't have enough info in the first pass
475 * to parse them correctly.
477 op->named.data = aml_op_start;
478 op->named.length = (u32) (parser_state->pkg_end -
483 parser_state->aml = parser_state->pkg_end;
484 walk_state->arg_count = 0;
490 if (walk_state->control_state) {
491 walk_state->control_state->control.package_end =
492 parser_state->pkg_end;
498 /* No action for all other opcodes */
505 /* Check for arguments that need to be processed */
507 if (walk_state->arg_count) {
509 * There are arguments (complex ones), push Op and
510 * prepare for argument
512 status = acpi_ps_push_scope (parser_state, op,
513 walk_state->arg_types, walk_state->arg_count);
514 if (ACPI_FAILURE (status)) {
522 * All arguments have been processed -- Op is complete,
525 walk_state->op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
526 if (walk_state->op_info->flags & AML_NAMED) {
527 if (acpi_gbl_depth) {
531 if (op->common.aml_opcode == AML_REGION_OP) {
533 * Skip parsing of control method or opregion body,
534 * because we don't have enough info in the first pass
535 * to parse them correctly.
537 * Completed parsing an op_region declaration, we now
540 op->named.length = (u32) (parser_state->aml - op->named.data);
544 if (walk_state->op_info->flags & AML_CREATE) {
546 * Backup to beginning of create_xXXfield declaration (1 for
549 * body_length is unknown until we parse the body
551 op->named.length = (u32) (parser_state->aml - op->named.data);
554 /* This op complete, notify the dispatcher */
556 if (walk_state->ascending_callback != NULL) {
558 walk_state->opcode = op->common.aml_opcode;
560 status = walk_state->ascending_callback (walk_state);
561 status = acpi_ps_next_parse_state (walk_state, op, status);
562 if (status == AE_CTRL_PENDING) {
571 * Finished one argument of the containing scope
573 parser_state->scope->parse_scope.arg_count--;
575 /* Finished with pre_op */
578 acpi_ps_free_op (pre_op);
582 /* Close this Op (will result in parse subtree deletion) */
584 status2 = acpi_ps_complete_this_op (walk_state, op);
585 if (ACPI_FAILURE (status2)) {
586 return_ACPI_STATUS (status2);
595 case AE_CTRL_TRANSFER:
597 /* We are about to transfer to a called method. */
599 walk_state->prev_op = op;
600 walk_state->prev_arg_types = walk_state->arg_types;
601 return_ACPI_STATUS (status);
606 acpi_ps_pop_scope (parser_state, &op,
607 &walk_state->arg_types, &walk_state->arg_count);
611 walk_state->op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
612 walk_state->opcode = op->common.aml_opcode;
614 status = walk_state->ascending_callback (walk_state);
615 status = acpi_ps_next_parse_state (walk_state, op, status);
617 status2 = acpi_ps_complete_this_op (walk_state, op);
618 if (ACPI_FAILURE (status2)) {
619 return_ACPI_STATUS (status2);
628 case AE_CTRL_CONTINUE:
630 /* Pop off scopes until we find the While */
632 while (!op || (op->common.aml_opcode != AML_WHILE_OP)) {
633 acpi_ps_pop_scope (parser_state, &op,
634 &walk_state->arg_types, &walk_state->arg_count);
637 /* Close this iteration of the While loop */
640 walk_state->op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
641 walk_state->opcode = op->common.aml_opcode;
643 status = walk_state->ascending_callback (walk_state);
644 status = acpi_ps_next_parse_state (walk_state, op, status);
646 status2 = acpi_ps_complete_this_op (walk_state, op);
647 if (ACPI_FAILURE (status2)) {
648 return_ACPI_STATUS (status2);
656 case AE_CTRL_TERMINATE:
663 status2 = acpi_ps_complete_this_op (walk_state, op);
664 if (ACPI_FAILURE (status2)) {
665 return_ACPI_STATUS (status2);
668 acpi_ps_pop_scope (parser_state, &op,
669 &walk_state->arg_types, &walk_state->arg_count);
673 return_ACPI_STATUS (status);
676 default: /* All other non-AE_OK status */
680 status2 = acpi_ps_complete_this_op (walk_state, op);
681 if (ACPI_FAILURE (status2)) {
682 return_ACPI_STATUS (status2);
685 acpi_ps_pop_scope (parser_state, &op,
686 &walk_state->arg_types, &walk_state->arg_count);
692 * TBD: Cleanup parse ops on error
696 acpi_ps_pop_scope (parser_state, &op,
697 &walk_state->arg_types, &walk_state->arg_count);
700 walk_state->prev_op = op;
701 walk_state->prev_arg_types = walk_state->arg_types;
702 return_ACPI_STATUS (status);
705 /* This scope complete? */
707 if (acpi_ps_has_completed_scope (parser_state)) {
708 acpi_ps_pop_scope (parser_state, &op,
709 &walk_state->arg_types, &walk_state->arg_count);
710 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Popped scope, Op=%p\n", op));
716 } /* while parser_state->Aml */
720 * Complete the last Op (if not completed), and clear the scope stack.
721 * It is easily possible to end an AML "package" with an unbounded number
722 * of open scopes (such as when several ASL blocks are closed with
723 * sequential closing braces). We want to terminate each one cleanly.
725 ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "AML package complete at Op %p\n", op));
728 if (walk_state->ascending_callback != NULL) {
730 walk_state->op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
731 walk_state->opcode = op->common.aml_opcode;
733 status = walk_state->ascending_callback (walk_state);
734 status = acpi_ps_next_parse_state (walk_state, op, status);
735 if (status == AE_CTRL_PENDING) {
740 if (status == AE_CTRL_TERMINATE) {
746 status2 = acpi_ps_complete_this_op (walk_state, op);
747 if (ACPI_FAILURE (status2)) {
748 return_ACPI_STATUS (status2);
752 acpi_ps_pop_scope (parser_state, &op,
753 &walk_state->arg_types, &walk_state->arg_count);
757 return_ACPI_STATUS (status);
760 else if (ACPI_FAILURE (status)) {
761 /* First error is most important */
763 (void) acpi_ps_complete_this_op (walk_state, op);
764 return_ACPI_STATUS (status);
768 status2 = acpi_ps_complete_this_op (walk_state, op);
769 if (ACPI_FAILURE (status2)) {
770 return_ACPI_STATUS (status2);
774 acpi_ps_pop_scope (parser_state, &op, &walk_state->arg_types,
775 &walk_state->arg_count);
779 return_ACPI_STATUS (status);