drivers/acpi/parser/psloop.c

   1 /******************************************************************************
   2  *
   3  * Module Name: psloop - Main AML parse loop
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2008, Intel Corp.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  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.
  25  *
  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.
  29  *
  30  * NO WARRANTY
  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.
  42  */
  43
  44 /*
  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[].
  50  */
  51
  52 #include <acpi/acpi.h>
  53 #include <acpi/accommon.h>
  54 #include <acpi/acparser.h>
  55 #include <acpi/acdispat.h>
  56 #include <acpi/amlcode.h>
  57
  58 #define _COMPONENT          ACPI_PARSER
  59 ACPI_MODULE_NAME("psloop")
  60
  61 static u32 acpi_gbl_depth = 0;
  62
  63 /* Local prototypes */
  64
  65 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state);
  66
  67 static acpi_status
  68 acpi_ps_build_named_op(struct acpi_walk_state *walk_state,
  69                        u8 * aml_op_start,
  70                        union acpi_parse_object *unnamed_op,
  71                        union acpi_parse_object **op);
  72
  73 static acpi_status
  74 acpi_ps_create_op(struct acpi_walk_state *walk_state,
  75                   u8 * aml_op_start, union acpi_parse_object **new_op);
  76
  77 static acpi_status
  78 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
  79                       u8 * aml_op_start, union acpi_parse_object *op);
  80
  81 static acpi_status
  82 acpi_ps_complete_op(struct acpi_walk_state *walk_state,
  83                     union acpi_parse_object **op, acpi_status status);
  84
  85 static acpi_status
  86 acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
  87                           union acpi_parse_object *op, acpi_status status);
  88
  89 /*******************************************************************************
  90  *
  91  * FUNCTION:    acpi_ps_get_aml_opcode
  92  *
  93  * PARAMETERS:  walk_state          - Current state
  94  *
  95  * RETURN:      Status
  96  *
  97  * DESCRIPTION: Extract the next AML opcode from the input stream.
  98  *
  99  ******************************************************************************/
 100
 101 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state)
 102 {
 103
 104         ACPI_FUNCTION_TRACE_PTR(ps_get_aml_opcode, walk_state);
 105
 106         walk_state->aml_offset =
 107             (u32) ACPI_PTR_DIFF(walk_state->parser_state.aml,
 108                                 walk_state->parser_state.aml_start);
 109         walk_state->opcode = acpi_ps_peek_opcode(&(walk_state->parser_state));
 110
 111         /*
 112          * First cut to determine what we have found:
 113          * 1) A valid AML opcode
 114          * 2) A name string
 115          * 3) An unknown/invalid opcode
 116          */
 117         walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
 118
 119         switch (walk_state->op_info->class) {
 120         case AML_CLASS_ASCII:
 121         case AML_CLASS_PREFIX:
 122                 /*
 123                  * Starts with a valid prefix or ASCII char, this is a name
 124                  * string. Convert the bare name string to a namepath.
 125                  */
 126                 walk_state->opcode = AML_INT_NAMEPATH_OP;
 127                 walk_state->arg_types = ARGP_NAMESTRING;
 128                 break;
 129
 130         case AML_CLASS_UNKNOWN:
 131
 132                 /* The opcode is unrecognized. Just skip unknown opcodes */
 133
 134                 ACPI_ERROR((AE_INFO,
 135                             "Found unknown opcode %X at AML address %p offset %X, ignoring",
 136                             walk_state->opcode, walk_state->parser_state.aml,
 137                             walk_state->aml_offset));
 138
 139                 ACPI_DUMP_BUFFER(walk_state->parser_state.aml, 128);
 140
 141                 /* Assume one-byte bad opcode */
 142
 143                 walk_state->parser_state.aml++;
 144                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 145
 146         default:
 147
 148                 /* Found opcode info, this is a normal opcode */
 149
 150                 walk_state->parser_state.aml +=
 151                     acpi_ps_get_opcode_size(walk_state->opcode);
 152                 walk_state->arg_types = walk_state->op_info->parse_args;
 153                 break;
 154         }
 155
 156         return_ACPI_STATUS(AE_OK);
 157 }
 158
 159 /*******************************************************************************
 160  *
 161  * FUNCTION:    acpi_ps_build_named_op
 162  *
 163  * PARAMETERS:  walk_state          - Current state
 164  *              aml_op_start        - Begin of named Op in AML
 165  *              unnamed_op          - Early Op (not a named Op)
 166  *              Op                  - Returned Op
 167  *
 168  * RETURN:      Status
 169  *
 170  * DESCRIPTION: Parse a named Op
 171  *
 172  ******************************************************************************/
 173
 174 static acpi_status
 175 acpi_ps_build_named_op(struct acpi_walk_state *walk_state,
 176                        u8 * aml_op_start,
 177                        union acpi_parse_object *unnamed_op,
 178                        union acpi_parse_object **op)
 179 {
 180         acpi_status status = AE_OK;
 181         union acpi_parse_object *arg = NULL;
 182
 183         ACPI_FUNCTION_TRACE_PTR(ps_build_named_op, walk_state);
 184
 185         unnamed_op->common.value.arg = NULL;
 186         unnamed_op->common.arg_list_length = 0;
 187         unnamed_op->common.aml_opcode = walk_state->opcode;
 188
 189         /*
 190          * Get and append arguments until we find the node that contains
 191          * the name (the type ARGP_NAME).
 192          */
 193         while (GET_CURRENT_ARG_TYPE(walk_state->arg_types) &&
 194                (GET_CURRENT_ARG_TYPE(walk_state->arg_types) != ARGP_NAME)) {
 195                 status =
 196                     acpi_ps_get_next_arg(walk_state,
 197                                          &(walk_state->parser_state),
 198                                          GET_CURRENT_ARG_TYPE(walk_state->
 199                                                               arg_types), &arg);
 200                 if (ACPI_FAILURE(status)) {
 201                         return_ACPI_STATUS(status);
 202                 }
 203
 204                 acpi_ps_append_arg(unnamed_op, arg);
 205                 INCREMENT_ARG_LIST(walk_state->arg_types);
 206         }
 207
 208         /*
 209          * Make sure that we found a NAME and didn't run out of arguments
 210          */
 211         if (!GET_CURRENT_ARG_TYPE(walk_state->arg_types)) {
 212                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
 213         }
 214
 215         /* We know that this arg is a name, move to next arg */
 216
 217         INCREMENT_ARG_LIST(walk_state->arg_types);
 218
 219         /*
 220          * Find the object. This will either insert the object into
 221          * the namespace or simply look it up
 222          */
 223         walk_state->op = NULL;
 224
 225         status = walk_state->descending_callback(walk_state, op);
 226         if (ACPI_FAILURE(status)) {
 227                 ACPI_EXCEPTION((AE_INFO, status, "During name lookup/catalog"));
 228                 return_ACPI_STATUS(status);
 229         }
 230
 231         if (!*op) {
 232                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 233         }
 234
 235         status = acpi_ps_next_parse_state(walk_state, *op, status);
 236         if (ACPI_FAILURE(status)) {
 237                 if (status == AE_CTRL_PENDING) {
 238                         return_ACPI_STATUS(AE_CTRL_PARSE_PENDING);
 239                 }
 240                 return_ACPI_STATUS(status);
 241         }
 242
 243         acpi_ps_append_arg(*op, unnamed_op->common.value.arg);
 244         acpi_gbl_depth++;
 245
 246         if ((*op)->common.aml_opcode == AML_REGION_OP ||
 247             (*op)->common.aml_opcode == AML_DATA_REGION_OP) {
 248                 /*
 249                  * Defer final parsing of an operation_region body, because we don't
 250                  * have enough info in the first pass to parse it correctly (i.e.,
 251                  * there may be method calls within the term_arg elements of the body.)
 252                  *
 253                  * However, we must continue parsing because the opregion is not a
 254                  * standalone package -- we don't know where the end is at this point.
 255                  *
 256                  * (Length is unknown until parse of the body complete)
 257                  */
 258                 (*op)->named.data = aml_op_start;
 259                 (*op)->named.length = 0;
 260         }
 261
 262         return_ACPI_STATUS(AE_OK);
 263 }
 264
 265 /*******************************************************************************
 266  *
 267  * FUNCTION:    acpi_ps_create_op
 268  *
 269  * PARAMETERS:  walk_state          - Current state
 270  *              aml_op_start        - Op start in AML
 271  *              new_op              - Returned Op
 272  *
 273  * RETURN:      Status
 274  *
 275  * DESCRIPTION: Get Op from AML
 276  *
 277  ******************************************************************************/
 278
 279 static acpi_status
 280 acpi_ps_create_op(struct acpi_walk_state *walk_state,
 281                   u8 * aml_op_start, union acpi_parse_object **new_op)
 282 {
 283         acpi_status status = AE_OK;
 284         union acpi_parse_object *op;
 285         union acpi_parse_object *named_op = NULL;
 286         union acpi_parse_object *parent_scope;
 287         u8 argument_count;
 288         const struct acpi_opcode_info *op_info;
 289
 290         ACPI_FUNCTION_TRACE_PTR(ps_create_op, walk_state);
 291
 292         status = acpi_ps_get_aml_opcode(walk_state);
 293         if (status == AE_CTRL_PARSE_CONTINUE) {
 294                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 295         }
 296
 297         /* Create Op structure and append to parent's argument list */
 298
 299         walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
 300         op = acpi_ps_alloc_op(walk_state->opcode);
 301         if (!op) {
 302                 return_ACPI_STATUS(AE_NO_MEMORY);
 303         }
 304
 305         if (walk_state->op_info->flags & AML_NAMED) {
 306                 status =
 307                     acpi_ps_build_named_op(walk_state, aml_op_start, op,
 308                                            &named_op);
 309                 acpi_ps_free_op(op);
 310                 if (ACPI_FAILURE(status)) {
 311                         return_ACPI_STATUS(status);
 312                 }
 313
 314                 *new_op = named_op;
 315                 return_ACPI_STATUS(AE_OK);
 316         }
 317
 318         /* Not a named opcode, just allocate Op and append to parent */
 319
 320         if (walk_state->op_info->flags & AML_CREATE) {
 321                 /*
 322                  * Backup to beginning of create_xXXfield declaration
 323                  * body_length is unknown until we parse the body
 324                  */
 325                 op->named.data = aml_op_start;
 326                 op->named.length = 0;
 327         }
 328
 329         if (walk_state->opcode == AML_BANK_FIELD_OP) {
 330                 /*
 331                  * Backup to beginning of bank_field declaration
 332                  * body_length is unknown until we parse the body
 333                  */
 334                 op->named.data = aml_op_start;
 335                 op->named.length = 0;
 336         }
 337
 338         parent_scope = acpi_ps_get_parent_scope(&(walk_state->parser_state));
 339         acpi_ps_append_arg(parent_scope, op);
 340
 341         if (parent_scope) {
 342                 op_info =
 343                     acpi_ps_get_opcode_info(parent_scope->common.aml_opcode);
 344                 if (op_info->flags & AML_HAS_TARGET) {
 345                         argument_count =
 346                             acpi_ps_get_argument_count(op_info->type);
 347                         if (parent_scope->common.arg_list_length >
 348                             argument_count) {
 349                                 op->common.flags |= ACPI_PARSEOP_TARGET;
 350                         }
 351                 } else if (parent_scope->common.aml_opcode == AML_INCREMENT_OP) {
 352                         op->common.flags |= ACPI_PARSEOP_TARGET;
 353                 }
 354         }
 355
 356         if (walk_state->descending_callback != NULL) {
 357                 /*
 358                  * Find the object. This will either insert the object into
 359                  * the namespace or simply look it up
 360                  */
 361                 walk_state->op = *new_op = op;
 362
 363                 status = walk_state->descending_callback(walk_state, &op);
 364                 status = acpi_ps_next_parse_state(walk_state, op, status);
 365                 if (status == AE_CTRL_PENDING) {
 366                         status = AE_CTRL_PARSE_PENDING;
 367                 }
 368         }
 369
 370         return_ACPI_STATUS(status);
 371 }
 372
 373 /*******************************************************************************
 374  *
 375  * FUNCTION:    acpi_ps_get_arguments
 376  *
 377  * PARAMETERS:  walk_state          - Current state
 378  *              aml_op_start        - Op start in AML
 379  *              Op                  - Current Op
 380  *
 381  * RETURN:      Status
 382  *
 383  * DESCRIPTION: Get arguments for passed Op.
 384  *
 385  ******************************************************************************/
 386
 387 static acpi_status
 388 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
 389                       u8 * aml_op_start, union acpi_parse_object *op)
 390 {
 391         acpi_status status = AE_OK;
 392         union acpi_parse_object *arg = NULL;
 393
 394         ACPI_FUNCTION_TRACE_PTR(ps_get_arguments, walk_state);
 395
 396         switch (op->common.aml_opcode) {
 397         case AML_BYTE_OP:       /* AML_BYTEDATA_ARG */
 398         case AML_WORD_OP:       /* AML_WORDDATA_ARG */
 399         case AML_DWORD_OP:      /* AML_DWORDATA_ARG */
 400         case AML_QWORD_OP:      /* AML_QWORDATA_ARG */
 401         case AML_STRING_OP:     /* AML_ASCIICHARLIST_ARG */
 402
 403                 /* Fill in constant or string argument directly */
 404
 405                 acpi_ps_get_next_simple_arg(&(walk_state->parser_state),
 406                                             GET_CURRENT_ARG_TYPE(walk_state->
 407                                                                  arg_types),
 408                                             op);
 409                 break;
 410
 411         case AML_INT_NAMEPATH_OP:       /* AML_NAMESTRING_ARG */
 412
 413                 status =
 414                     acpi_ps_get_next_namepath(walk_state,
 415                                               &(walk_state->parser_state), op,
 416                                               1);
 417                 if (ACPI_FAILURE(status)) {
 418                         return_ACPI_STATUS(status);
 419                 }
 420
 421                 walk_state->arg_types = 0;
 422                 break;
 423
 424         default:
 425                 /*
 426                  * Op is not a constant or string, append each argument to the Op
 427                  */
 428                 while (GET_CURRENT_ARG_TYPE(walk_state->arg_types)
 429                        && !walk_state->arg_count) {
 430                         walk_state->aml_offset =
 431                             (u32) ACPI_PTR_DIFF(walk_state->parser_state.aml,
 432                                                 walk_state->parser_state.
 433                                                 aml_start);
 434
 435                         status =
 436                             acpi_ps_get_next_arg(walk_state,
 437                                                  &(walk_state->parser_state),
 438                                                  GET_CURRENT_ARG_TYPE
 439                                                  (walk_state->arg_types), &arg);
 440                         if (ACPI_FAILURE(status)) {
 441                                 return_ACPI_STATUS(status);
 442                         }
 443
 444                         if (arg) {
 445                                 arg->common.aml_offset = walk_state->aml_offset;
 446                                 acpi_ps_append_arg(op, arg);
 447                         }
 448
 449                         INCREMENT_ARG_LIST(walk_state->arg_types);
 450                 }
 451
 452                 /* Special processing for certain opcodes */
 453
 454                 /* TBD (remove): Temporary mechanism to disable this code if needed */
 455
 456 #ifdef ACPI_ENABLE_MODULE_LEVEL_CODE
 457
 458                 if ((walk_state->pass_number <= ACPI_IMODE_LOAD_PASS1) &&
 459                     ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) == 0)) {
 460                         /*
 461                          * We want to skip If/Else/While constructs during Pass1 because we
 462                          * want to actually conditionally execute the code during Pass2.
 463                          *
 464                          * Except for disassembly, where we always want to walk the
 465                          * If/Else/While packages
 466                          */
 467                         switch (op->common.aml_opcode) {
 468                         case AML_IF_OP:
 469                         case AML_ELSE_OP:
 470                         case AML_WHILE_OP:
 471
 472                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 473                                                   "Pass1: Skipping an If/Else/While body\n"));
 474
 475                                 /* Skip body of if/else/while in pass 1 */
 476
 477                                 walk_state->parser_state.aml =
 478                                     walk_state->parser_state.pkg_end;
 479                                 walk_state->arg_count = 0;
 480                                 break;
 481
 482                         default:
 483                                 break;
 484                         }
 485                 }
 486 #endif
 487
 488                 switch (op->common.aml_opcode) {
 489                 case AML_METHOD_OP:
 490                         /*
 491                          * Skip parsing of control method because we don't have enough
 492                          * info in the first pass to parse it correctly.
 493                          *
 494                          * Save the length and address of the body
 495                          */
 496                         op->named.data = walk_state->parser_state.aml;
 497                         op->named.length = (u32)
 498                             (walk_state->parser_state.pkg_end -
 499                              walk_state->parser_state.aml);
 500
 501                         /* Skip body of method */
 502
 503                         walk_state->parser_state.aml =
 504                             walk_state->parser_state.pkg_end;
 505                         walk_state->arg_count = 0;
 506                         break;
 507
 508                 case AML_BUFFER_OP:
 509                 case AML_PACKAGE_OP:
 510                 case AML_VAR_PACKAGE_OP:
 511
 512                         if ((op->common.parent) &&
 513                             (op->common.parent->common.aml_opcode ==
 514                              AML_NAME_OP)
 515                             && (walk_state->pass_number <=
 516                                 ACPI_IMODE_LOAD_PASS2)) {
 517                                 /*
 518                                  * Skip parsing of Buffers and Packages because we don't have
 519                                  * enough info in the first pass to parse them correctly.
 520                                  */
 521                                 op->named.data = aml_op_start;
 522                                 op->named.length = (u32)
 523                                     (walk_state->parser_state.pkg_end -
 524                                      aml_op_start);
 525
 526                                 /* Skip body */
 527
 528                                 walk_state->parser_state.aml =
 529                                     walk_state->parser_state.pkg_end;
 530                                 walk_state->arg_count = 0;
 531                         }
 532                         break;
 533
 534                 case AML_WHILE_OP:
 535
 536                         if (walk_state->control_state) {
 537                                 walk_state->control_state->control.package_end =
 538                                     walk_state->parser_state.pkg_end;
 539                         }
 540                         break;
 541
 542                 default:
 543
 544                         /* No action for all other opcodes */
 545                         break;
 546                 }
 547
 548                 break;
 549         }
 550
 551         return_ACPI_STATUS(AE_OK);
 552 }
 553
 554 /*******************************************************************************
 555  *
 556  * FUNCTION:    acpi_ps_complete_op
 557  *
 558  * PARAMETERS:  walk_state          - Current state
 559  *              Op                  - Returned Op
 560  *              Status              - Parse status before complete Op
 561  *
 562  * RETURN:      Status
 563  *
 564  * DESCRIPTION: Complete Op
 565  *
 566  ******************************************************************************/
 567
 568 static acpi_status
 569 acpi_ps_complete_op(struct acpi_walk_state *walk_state,
 570                     union acpi_parse_object **op, acpi_status status)
 571 {
 572         acpi_status status2;
 573
 574         ACPI_FUNCTION_TRACE_PTR(ps_complete_op, walk_state);
 575
 576         /*
 577          * Finished one argument of the containing scope
 578          */
 579         walk_state->parser_state.scope->parse_scope.arg_count--;
 580
 581         /* Close this Op (will result in parse subtree deletion) */
 582
 583         status2 = acpi_ps_complete_this_op(walk_state, *op);
 584         if (ACPI_FAILURE(status2)) {
 585                 return_ACPI_STATUS(status2);
 586         }
 587
 588         *op = NULL;
 589
 590         switch (status) {
 591         case AE_OK:
 592                 break;
 593
 594         case AE_CTRL_TRANSFER:
 595
 596                 /* We are about to transfer to a called method */
 597
 598                 walk_state->prev_op = NULL;
 599                 walk_state->prev_arg_types = walk_state->arg_types;
 600                 return_ACPI_STATUS(status);
 601
 602         case AE_CTRL_END:
 603
 604                 acpi_ps_pop_scope(&(walk_state->parser_state), op,
 605                                   &walk_state->arg_types,
 606                                   &walk_state->arg_count);
 607
 608                 if (*op) {
 609                         walk_state->op = *op;
 610                         walk_state->op_info =
 611                             acpi_ps_get_opcode_info((*op)->common.aml_opcode);
 612                         walk_state->opcode = (*op)->common.aml_opcode;
 613
 614                         status = walk_state->ascending_callback(walk_state);
 615                         status =
 616                             acpi_ps_next_parse_state(walk_state, *op, status);
 617
 618                         status2 = acpi_ps_complete_this_op(walk_state, *op);
 619                         if (ACPI_FAILURE(status2)) {
 620                                 return_ACPI_STATUS(status2);
 621                         }
 622                 }
 623
 624                 status = AE_OK;
 625                 break;
 626
 627         case AE_CTRL_BREAK:
 628         case AE_CTRL_CONTINUE:
 629
 630                 /* Pop off scopes until we find the While */
 631
 632                 while (!(*op) || ((*op)->common.aml_opcode != AML_WHILE_OP)) {
 633                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 634                                           &walk_state->arg_types,
 635                                           &walk_state->arg_count);
 636                 }
 637
 638                 /* Close this iteration of the While loop */
 639
 640                 walk_state->op = *op;
 641                 walk_state->op_info =
 642                     acpi_ps_get_opcode_info((*op)->common.aml_opcode);
 643                 walk_state->opcode = (*op)->common.aml_opcode;
 644
 645                 status = walk_state->ascending_callback(walk_state);
 646                 status = acpi_ps_next_parse_state(walk_state, *op, status);
 647
 648                 status2 = acpi_ps_complete_this_op(walk_state, *op);
 649                 if (ACPI_FAILURE(status2)) {
 650                         return_ACPI_STATUS(status2);
 651                 }
 652
 653                 status = AE_OK;
 654                 break;
 655
 656         case AE_CTRL_TERMINATE:
 657
 658                 /* Clean up */
 659                 do {
 660                         if (*op) {
 661                                 status2 =
 662                                     acpi_ps_complete_this_op(walk_state, *op);
 663                                 if (ACPI_FAILURE(status2)) {
 664                                         return_ACPI_STATUS(status2);
 665                                 }
 666
 667                                 acpi_ut_delete_generic_state
 668                                     (acpi_ut_pop_generic_state
 669                                      (&walk_state->control_state));
 670                         }
 671
 672                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 673                                           &walk_state->arg_types,
 674                                           &walk_state->arg_count);
 675
 676                 } while (*op);
 677
 678                 return_ACPI_STATUS(AE_OK);
 679
 680         default:                /* All other non-AE_OK status */
 681
 682                 do {
 683                         if (*op) {
 684                                 status2 =
 685                                     acpi_ps_complete_this_op(walk_state, *op);
 686                                 if (ACPI_FAILURE(status2)) {
 687                                         return_ACPI_STATUS(status2);
 688                                 }
 689                         }
 690
 691                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 692                                           &walk_state->arg_types,
 693                                           &walk_state->arg_count);
 694
 695                 } while (*op);
 696
 697 #if 0
 698                 /*
 699                  * TBD: Cleanup parse ops on error
 700                  */
 701                 if (*op == NULL) {
 702                         acpi_ps_pop_scope(parser_state, op,
 703                                           &walk_state->arg_types,
 704                                           &walk_state->arg_count);
 705                 }
 706 #endif
 707                 walk_state->prev_op = NULL;
 708                 walk_state->prev_arg_types = walk_state->arg_types;
 709                 return_ACPI_STATUS(status);
 710         }
 711
 712         /* This scope complete? */
 713
 714         if (acpi_ps_has_completed_scope(&(walk_state->parser_state))) {
 715                 acpi_ps_pop_scope(&(walk_state->parser_state), op,
 716                                   &walk_state->arg_types,
 717                                   &walk_state->arg_count);
 718                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Popped scope, Op=%p\n", *op));
 719         } else {
 720                 *op = NULL;
 721         }
 722
 723         ACPI_PREEMPTION_POINT();
 724
 725         return_ACPI_STATUS(AE_OK);
 726 }
 727
 728 /*******************************************************************************
 729  *
 730  * FUNCTION:    acpi_ps_complete_final_op
 731  *
 732  * PARAMETERS:  walk_state          - Current state
 733  *              Op                  - Current Op
 734  *              Status              - Current parse status before complete last
 735  *                                    Op
 736  *
 737  * RETURN:      Status
 738  *
 739  * DESCRIPTION: Complete last Op.
 740  *
 741  ******************************************************************************/
 742
 743 static acpi_status
 744 acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
 745                           union acpi_parse_object *op, acpi_status status)
 746 {
 747         acpi_status status2;
 748
 749         ACPI_FUNCTION_TRACE_PTR(ps_complete_final_op, walk_state);
 750
 751         /*
 752          * Complete the last Op (if not completed), and clear the scope stack.
 753          * It is easily possible to end an AML "package" with an unbounded number
 754          * of open scopes (such as when several ASL blocks are closed with
 755          * sequential closing braces). We want to terminate each one cleanly.
 756          */
 757         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "AML package complete at Op %p\n",
 758                           op));
 759         do {
 760                 if (op) {
 761                         if (walk_state->ascending_callback != NULL) {
 762                                 walk_state->op = op;
 763                                 walk_state->op_info =
 764                                     acpi_ps_get_opcode_info(op->common.
 765                                                             aml_opcode);
 766                                 walk_state->opcode = op->common.aml_opcode;
 767
 768                                 status =
 769                                     walk_state->ascending_callback(walk_state);
 770                                 status =
 771                                     acpi_ps_next_parse_state(walk_state, op,
 772                                                              status);
 773                                 if (status == AE_CTRL_PENDING) {
 774                                         status =
 775                                             acpi_ps_complete_op(walk_state, &op,
 776                                                                 AE_OK);
 777                                         if (ACPI_FAILURE(status)) {
 778                                                 return_ACPI_STATUS(status);
 779                                         }
 780                                 }
 781
 782                                 if (status == AE_CTRL_TERMINATE) {
 783                                         status = AE_OK;
 784
 785                                         /* Clean up */
 786                                         do {
 787                                                 if (op) {
 788                                                         status2 =
 789                                                             acpi_ps_complete_this_op
 790                                                             (walk_state, op);
 791                                                         if (ACPI_FAILURE
 792                                                             (status2)) {
 793                                                                 return_ACPI_STATUS
 794                                                                     (status2);
 795                                                         }
 796                                                 }
 797
 798                                                 acpi_ps_pop_scope(&
 799                                                                   (walk_state->
 800                                                                    parser_state),
 801                                                                   &op,
 802                                                                   &walk_state->
 803                                                                   arg_types,
 804                                                                   &walk_state->
 805                                                                   arg_count);
 806
 807                                         } while (op);
 808
 809                                         return_ACPI_STATUS(status);
 810                                 }
 811
 812                                 else if (ACPI_FAILURE(status)) {
 813
 814                                         /* First error is most important */
 815
 816                                         (void)
 817                                             acpi_ps_complete_this_op(walk_state,
 818                                                                      op);
 819                                         return_ACPI_STATUS(status);
 820                                 }
 821                         }
 822
 823                         status2 = acpi_ps_complete_this_op(walk_state, op);
 824                         if (ACPI_FAILURE(status2)) {
 825                                 return_ACPI_STATUS(status2);
 826                         }
 827                 }
 828
 829                 acpi_ps_pop_scope(&(walk_state->parser_state), &op,
 830                                   &walk_state->arg_types,
 831                                   &walk_state->arg_count);
 832
 833         } while (op);
 834
 835         return_ACPI_STATUS(status);
 836 }
 837
 838 /*******************************************************************************
 839  *
 840  * FUNCTION:    acpi_ps_parse_loop
 841  *
 842  * PARAMETERS:  walk_state          - Current state
 843  *
 844  * RETURN:      Status
 845  *
 846  * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
 847  *              a tree of ops.
 848  *
 849  ******************************************************************************/
 850
 851 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
 852 {
 853         acpi_status status = AE_OK;
 854         union acpi_parse_object *op = NULL;     /* current op */
 855         struct acpi_parse_state *parser_state;
 856         u8 *aml_op_start = NULL;
 857
 858         ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);
 859
 860         if (walk_state->descending_callback == NULL) {
 861                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 862         }
 863
 864         parser_state = &walk_state->parser_state;
 865         walk_state->arg_types = 0;
 866
 867 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
 868
 869         if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
 870
 871                 /* We are restarting a preempted control method */
 872
 873                 if (acpi_ps_has_completed_scope(parser_state)) {
 874                         /*
 875                          * We must check if a predicate to an IF or WHILE statement
 876                          * was just completed
 877                          */
 878                         if ((parser_state->scope->parse_scope.op) &&
 879                             ((parser_state->scope->parse_scope.op->common.
 880                               aml_opcode == AML_IF_OP)
 881                              || (parser_state->scope->parse_scope.op->common.
 882                                  aml_opcode == AML_WHILE_OP))
 883                             && (walk_state->control_state)
 884                             && (walk_state->control_state->common.state ==
 885                                 ACPI_CONTROL_PREDICATE_EXECUTING)) {
 886                                 /*
 887                                  * A predicate was just completed, get the value of the
 888                                  * predicate and branch based on that value
 889                                  */
 890                                 walk_state->op = NULL;
 891                                 status =
 892                                     acpi_ds_get_predicate_value(walk_state,
 893                                                                 ACPI_TO_POINTER
 894                                                                 (TRUE));
 895                                 if (ACPI_FAILURE(status)
 896                                     && ((status & AE_CODE_MASK) !=
 897                                         AE_CODE_CONTROL)) {
 898                                         if (status == AE_AML_NO_RETURN_VALUE) {
 899                                                 ACPI_EXCEPTION((AE_INFO, status,
 900                                                                 "Invoked method did not return a value"));
 901
 902                                         }
 903
 904                                         ACPI_EXCEPTION((AE_INFO, status,
 905                                                         "GetPredicate Failed"));
 906                                         return_ACPI_STATUS(status);
 907                                 }
 908
 909                                 status =
 910                                     acpi_ps_next_parse_state(walk_state, op,
 911                                                              status);
 912                         }
 913
 914                         acpi_ps_pop_scope(parser_state, &op,
 915                                           &walk_state->arg_types,
 916                                           &walk_state->arg_count);
 917                         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 918                                           "Popped scope, Op=%p\n", op));
 919                 } else if (walk_state->prev_op) {
 920
 921                         /* We were in the middle of an op */
 922
 923                         op = walk_state->prev_op;
 924                         walk_state->arg_types = walk_state->prev_arg_types;
 925                 }
 926         }
 927 #endif
 928
 929         /* Iterative parsing loop, while there is more AML to process: */
 930
 931         while ((parser_state->aml < parser_state->aml_end) || (op)) {
 932                 aml_op_start = parser_state->aml;
 933                 if (!op) {
 934                         status =
 935                             acpi_ps_create_op(walk_state, aml_op_start, &op);
 936                         if (ACPI_FAILURE(status)) {
 937                                 if (status == AE_CTRL_PARSE_CONTINUE) {
 938                                         continue;
 939                                 }
 940
 941                                 if (status == AE_CTRL_PARSE_PENDING) {
 942                                         status = AE_OK;
 943                                 }
 944
 945                                 status =
 946                                     acpi_ps_complete_op(walk_state, &op,
 947                                                         status);
 948                                 if (ACPI_FAILURE(status)) {
 949                                         return_ACPI_STATUS(status);
 950                                 }
 951
 952                                 continue;
 953                         }
 954
 955                         op->common.aml_offset = walk_state->aml_offset;
 956
 957                         if (walk_state->op_info) {
 958                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 959                                                   "Opcode %4.4X [%s] Op %p Aml %p AmlOffset %5.5X\n",
 960                                                   (u32) op->common.aml_opcode,
 961                                                   walk_state->op_info->name, op,
 962                                                   parser_state->aml,
 963                                                   op->common.aml_offset));
 964                         }
 965                 }
 966
 967                 /*
 968                  * Start arg_count at zero because we don't know if there are
 969                  * any args yet
 970                  */
 971                 walk_state->arg_count = 0;
 972
 973                 /* Are there any arguments that must be processed? */
 974
 975                 if (walk_state->arg_types) {
 976
 977                         /* Get arguments */
 978
 979                         status =
 980                             acpi_ps_get_arguments(walk_state, aml_op_start, op);
 981                         if (ACPI_FAILURE(status)) {
 982                                 status =
 983                                     acpi_ps_complete_op(walk_state, &op,
 984                                                         status);
 985                                 if (ACPI_FAILURE(status)) {
 986                                         return_ACPI_STATUS(status);
 987                                 }
 988
 989                                 continue;
 990                         }
 991                 }
 992
 993                 /* Check for arguments that need to be processed */
 994
 995                 if (walk_state->arg_count) {
 996                         /*
 997                          * There are arguments (complex ones), push Op and
 998                          * prepare for argument
 999                          */
1000                         status = acpi_ps_push_scope(parser_state, op,
1001                                                     walk_state->arg_types,
1002                                                     walk_state->arg_count);
1003                         if (ACPI_FAILURE(status)) {
1004                                 status =
1005                                     acpi_ps_complete_op(walk_state, &op,
1006                                                         status);
1007                                 if (ACPI_FAILURE(status)) {
1008                                         return_ACPI_STATUS(status);
1009                                 }
1010
1011                                 continue;
1012                         }
1013
1014                         op = NULL;
1015                         continue;
1016                 }
1017
1018                 /*
1019                  * All arguments have been processed -- Op is complete,
1020                  * prepare for next
1021                  */
1022                 walk_state->op_info =
1023                     acpi_ps_get_opcode_info(op->common.aml_opcode);
1024                 if (walk_state->op_info->flags & AML_NAMED) {
1025                         if (acpi_gbl_depth) {
1026                                 acpi_gbl_depth--;
1027                         }
1028
1029                         if (op->common.aml_opcode == AML_REGION_OP ||
1030                             op->common.aml_opcode == AML_DATA_REGION_OP) {
1031                                 /*
1032                                  * Skip parsing of control method or opregion body,
1033                                  * because we don't have enough info in the first pass
1034                                  * to parse them correctly.
1035                                  *
1036                                  * Completed parsing an op_region declaration, we now
1037                                  * know the length.
1038                                  */
1039                                 op->named.length =
1040                                     (u32) (parser_state->aml - op->named.data);
1041                         }
1042                 }
1043
1044                 if (walk_state->op_info->flags & AML_CREATE) {
1045                         /*
1046                          * Backup to beginning of create_xXXfield declaration (1 for
1047                          * Opcode)
1048                          *
1049                          * body_length is unknown until we parse the body
1050                          */
1051                         op->named.length =
1052                             (u32) (parser_state->aml - op->named.data);
1053                 }
1054
1055                 if (op->common.aml_opcode == AML_BANK_FIELD_OP) {
1056                         /*
1057                          * Backup to beginning of bank_field declaration
1058                          *
1059                          * body_length is unknown until we parse the body
1060                          */
1061                         op->named.length =
1062                             (u32) (parser_state->aml - op->named.data);
1063                 }
1064
1065                 /* This op complete, notify the dispatcher */
1066
1067                 if (walk_state->ascending_callback != NULL) {
1068                         walk_state->op = op;
1069                         walk_state->opcode = op->common.aml_opcode;
1070
1071                         status = walk_state->ascending_callback(walk_state);
1072                         status =
1073                             acpi_ps_next_parse_state(walk_state, op, status);
1074                         if (status == AE_CTRL_PENDING) {
1075                                 status = AE_OK;
1076                         }
1077                 }
1078
1079                 status = acpi_ps_complete_op(walk_state, &op, status);
1080                 if (ACPI_FAILURE(status)) {
1081                         return_ACPI_STATUS(status);
1082                 }
1083
1084         }                       /* while parser_state->Aml */
1085
1086         status = acpi_ps_complete_final_op(walk_state, op, status);
1087         return_ACPI_STATUS(status);
1088 }