drivers/acpi/parser/psloop.c

   1 /******************************************************************************
   2  *
   3  * Module Name: psloop - Main AML parse loop
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2007, R. Byron Moore
   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/acparser.h>
  54 #include <acpi/acdispat.h>
  55 #include <acpi/amlcode.h>
  56
  57 #define _COMPONENT          ACPI_PARSER
  58 ACPI_MODULE_NAME("psloop")
  59
  60 static u32 acpi_gbl_depth = 0;
  61
  62 /* Local prototypes */
  63
  64 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state);
  65
  66 static acpi_status
  67 acpi_ps_build_named_op(struct acpi_walk_state *walk_state,
  68                        u8 * aml_op_start,
  69                        union acpi_parse_object *unnamed_op,
  70                        union acpi_parse_object **op);
  71
  72 static acpi_status
  73 acpi_ps_create_op(struct acpi_walk_state *walk_state,
  74                   u8 * aml_op_start, union acpi_parse_object **new_op);
  75
  76 static acpi_status
  77 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
  78                       u8 * aml_op_start, union acpi_parse_object *op);
  79
  80 static acpi_status
  81 acpi_ps_complete_op(struct acpi_walk_state *walk_state,
  82                     union acpi_parse_object **op, acpi_status status);
  83
  84 static acpi_status
  85 acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
  86                           union acpi_parse_object *op, acpi_status status);
  87
  88 /*******************************************************************************
  89  *
  90  * FUNCTION:    acpi_ps_get_aml_opcode
  91  *
  92  * PARAMETERS:  walk_state          - Current state
  93  *
  94  * RETURN:      Status
  95  *
  96  * DESCRIPTION: Extract the next AML opcode from the input stream.
  97  *
  98  ******************************************************************************/
  99
 100 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state)
 101 {
 102
 103         ACPI_FUNCTION_TRACE_PTR(ps_get_aml_opcode, walk_state);
 104
 105         walk_state->aml_offset =
 106             (u32) ACPI_PTR_DIFF(walk_state->parser_state.aml,
 107                                 walk_state->parser_state.aml_start);
 108         walk_state->opcode = acpi_ps_peek_opcode(&(walk_state->parser_state));
 109
 110         /*
 111          * First cut to determine what we have found:
 112          * 1) A valid AML opcode
 113          * 2) A name string
 114          * 3) An unknown/invalid opcode
 115          */
 116         walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
 117
 118         switch (walk_state->op_info->class) {
 119         case AML_CLASS_ASCII:
 120         case AML_CLASS_PREFIX:
 121                 /*
 122                  * Starts with a valid prefix or ASCII char, this is a name
 123                  * string. Convert the bare name string to a namepath.
 124                  */
 125                 walk_state->opcode = AML_INT_NAMEPATH_OP;
 126                 walk_state->arg_types = ARGP_NAMESTRING;
 127                 break;
 128
 129         case AML_CLASS_UNKNOWN:
 130
 131                 /* The opcode is unrecognized. Just skip unknown opcodes */
 132
 133                 ACPI_ERROR((AE_INFO,
 134                             "Found unknown opcode %X at AML address %p offset %X, ignoring",
 135                             walk_state->opcode, walk_state->parser_state.aml,
 136                             walk_state->aml_offset));
 137
 138                 ACPI_DUMP_BUFFER(walk_state->parser_state.aml, 128);
 139
 140                 /* Assume one-byte bad opcode */
 141
 142                 walk_state->parser_state.aml++;
 143                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 144
 145         default:
 146
 147                 /* Found opcode info, this is a normal opcode */
 148
 149                 walk_state->parser_state.aml +=
 150                     acpi_ps_get_opcode_size(walk_state->opcode);
 151                 walk_state->arg_types = walk_state->op_info->parse_args;
 152                 break;
 153         }
 154
 155         return_ACPI_STATUS(AE_OK);
 156 }
 157
 158 /*******************************************************************************
 159  *
 160  * FUNCTION:    acpi_ps_build_named_op
 161  *
 162  * PARAMETERS:  walk_state          - Current state
 163  *              aml_op_start        - Begin of named Op in AML
 164  *              unnamed_op          - Early Op (not a named Op)
 165  *              Op                  - Returned Op
 166  *
 167  * RETURN:      Status
 168  *
 169  * DESCRIPTION: Parse a named Op
 170  *
 171  ******************************************************************************/
 172
 173 static acpi_status
 174 acpi_ps_build_named_op(struct acpi_walk_state *walk_state,
 175                        u8 * aml_op_start,
 176                        union acpi_parse_object *unnamed_op,
 177                        union acpi_parse_object **op)
 178 {
 179         acpi_status status = AE_OK;
 180         union acpi_parse_object *arg = NULL;
 181
 182         ACPI_FUNCTION_TRACE_PTR(ps_build_named_op, walk_state);
 183
 184         unnamed_op->common.value.arg = NULL;
 185         unnamed_op->common.arg_list_length = 0;
 186         unnamed_op->common.aml_opcode = walk_state->opcode;
 187
 188         /*
 189          * Get and append arguments until we find the node that contains
 190          * the name (the type ARGP_NAME).
 191          */
 192         while (GET_CURRENT_ARG_TYPE(walk_state->arg_types) &&
 193                (GET_CURRENT_ARG_TYPE(walk_state->arg_types) != ARGP_NAME)) {
 194                 status =
 195                     acpi_ps_get_next_arg(walk_state,
 196                                          &(walk_state->parser_state),
 197                                          GET_CURRENT_ARG_TYPE(walk_state->
 198                                                               arg_types), &arg);
 199                 if (ACPI_FAILURE(status)) {
 200                         return_ACPI_STATUS(status);
 201                 }
 202
 203                 acpi_ps_append_arg(unnamed_op, arg);
 204                 INCREMENT_ARG_LIST(walk_state->arg_types);
 205         }
 206
 207         /*
 208          * Make sure that we found a NAME and didn't run out of arguments
 209          */
 210         if (!GET_CURRENT_ARG_TYPE(walk_state->arg_types)) {
 211                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
 212         }
 213
 214         /* We know that this arg is a name, move to next arg */
 215
 216         INCREMENT_ARG_LIST(walk_state->arg_types);
 217
 218         /*
 219          * Find the object. This will either insert the object into
 220          * the namespace or simply look it up
 221          */
 222         walk_state->op = NULL;
 223
 224         status = walk_state->descending_callback(walk_state, op);
 225         if (ACPI_FAILURE(status)) {
 226                 ACPI_EXCEPTION((AE_INFO, status, "During name lookup/catalog"));
 227                 return_ACPI_STATUS(status);
 228         }
 229
 230         if (!*op) {
 231                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 232         }
 233
 234         status = acpi_ps_next_parse_state(walk_state, *op, status);
 235         if (ACPI_FAILURE(status)) {
 236                 if (status == AE_CTRL_PENDING) {
 237                         return_ACPI_STATUS(AE_CTRL_PARSE_PENDING);
 238                 }
 239                 return_ACPI_STATUS(status);
 240         }
 241
 242         acpi_ps_append_arg(*op, unnamed_op->common.value.arg);
 243         acpi_gbl_depth++;
 244
 245         if ((*op)->common.aml_opcode == AML_REGION_OP ||
 246             (*op)->common.aml_opcode == AML_DATA_REGION_OP) {
 247                 /*
 248                  * Defer final parsing of an operation_region body, because we don't
 249                  * have enough info in the first pass to parse it correctly (i.e.,
 250                  * there may be method calls within the term_arg elements of the body.)
 251                  *
 252                  * However, we must continue parsing because the opregion is not a
 253                  * standalone package -- we don't know where the end is at this point.
 254                  *
 255                  * (Length is unknown until parse of the body complete)
 256                  */
 257                 (*op)->named.data = aml_op_start;
 258                 (*op)->named.length = 0;
 259         }
 260
 261         return_ACPI_STATUS(AE_OK);
 262 }
 263
 264 /*******************************************************************************
 265  *
 266  * FUNCTION:    acpi_ps_create_op
 267  *
 268  * PARAMETERS:  walk_state          - Current state
 269  *              aml_op_start        - Op start in AML
 270  *              new_op              - Returned Op
 271  *
 272  * RETURN:      Status
 273  *
 274  * DESCRIPTION: Get Op from AML
 275  *
 276  ******************************************************************************/
 277
 278 static acpi_status
 279 acpi_ps_create_op(struct acpi_walk_state *walk_state,
 280                   u8 * aml_op_start, union acpi_parse_object **new_op)
 281 {
 282         acpi_status status = AE_OK;
 283         union acpi_parse_object *op;
 284         union acpi_parse_object *named_op = NULL;
 285         union acpi_parse_object *parent_scope;
 286         u8 argument_count;
 287         const struct acpi_opcode_info *op_info;
 288
 289         ACPI_FUNCTION_TRACE_PTR(ps_create_op, walk_state);
 290
 291         status = acpi_ps_get_aml_opcode(walk_state);
 292         if (status == AE_CTRL_PARSE_CONTINUE) {
 293                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 294         }
 295
 296         /* Create Op structure and append to parent's argument list */
 297
 298         walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
 299         op = acpi_ps_alloc_op(walk_state->opcode);
 300         if (!op) {
 301                 return_ACPI_STATUS(AE_NO_MEMORY);
 302         }
 303
 304         if (walk_state->op_info->flags & AML_NAMED) {
 305                 status =
 306                     acpi_ps_build_named_op(walk_state, aml_op_start, op,
 307                                            &named_op);
 308                 acpi_ps_free_op(op);
 309                 if (ACPI_FAILURE(status)) {
 310                         return_ACPI_STATUS(status);
 311                 }
 312
 313                 *new_op = named_op;
 314                 return_ACPI_STATUS(AE_OK);
 315         }
 316
 317         /* Not a named opcode, just allocate Op and append to parent */
 318
 319         if (walk_state->op_info->flags & AML_CREATE) {
 320                 /*
 321                  * Backup to beginning of create_xXXfield declaration
 322                  * body_length is unknown until we parse the body
 323                  */
 324                 op->named.data = aml_op_start;
 325                 op->named.length = 0;
 326         }
 327
 328         parent_scope = acpi_ps_get_parent_scope(&(walk_state->parser_state));
 329         acpi_ps_append_arg(parent_scope, op);
 330
 331         if (parent_scope) {
 332                 op_info =
 333                     acpi_ps_get_opcode_info(parent_scope->common.aml_opcode);
 334                 if (op_info->flags & AML_HAS_TARGET) {
 335                         argument_count =
 336                             acpi_ps_get_argument_count(op_info->type);
 337                         if (parent_scope->common.arg_list_length >
 338                             argument_count) {
 339                                 op->common.flags |= ACPI_PARSEOP_TARGET;
 340                         }
 341                 } else if (parent_scope->common.aml_opcode == AML_INCREMENT_OP) {
 342                         op->common.flags |= ACPI_PARSEOP_TARGET;
 343                 }
 344         }
 345
 346         if (walk_state->descending_callback != NULL) {
 347                 /*
 348                  * Find the object. This will either insert the object into
 349                  * the namespace or simply look it up
 350                  */
 351                 walk_state->op = *new_op = op;
 352
 353                 status = walk_state->descending_callback(walk_state, &op);
 354                 status = acpi_ps_next_parse_state(walk_state, op, status);
 355                 if (status == AE_CTRL_PENDING) {
 356                         status = AE_CTRL_PARSE_PENDING;
 357                 }
 358         }
 359
 360         return_ACPI_STATUS(status);
 361 }
 362
 363 /*******************************************************************************
 364  *
 365  * FUNCTION:    acpi_ps_get_arguments
 366  *
 367  * PARAMETERS:  walk_state          - Current state
 368  *              aml_op_start        - Op start in AML
 369  *              Op                  - Current Op
 370  *
 371  * RETURN:      Status
 372  *
 373  * DESCRIPTION: Get arguments for passed Op.
 374  *
 375  ******************************************************************************/
 376
 377 static acpi_status
 378 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
 379                       u8 * aml_op_start, union acpi_parse_object *op)
 380 {
 381         acpi_status status = AE_OK;
 382         union acpi_parse_object *arg = NULL;
 383
 384         ACPI_FUNCTION_TRACE_PTR(ps_get_arguments, walk_state);
 385
 386         switch (op->common.aml_opcode) {
 387         case AML_BYTE_OP:       /* AML_BYTEDATA_ARG */
 388         case AML_WORD_OP:       /* AML_WORDDATA_ARG */
 389         case AML_DWORD_OP:      /* AML_DWORDATA_ARG */
 390         case AML_QWORD_OP:      /* AML_QWORDATA_ARG */
 391         case AML_STRING_OP:     /* AML_ASCIICHARLIST_ARG */
 392
 393                 /* Fill in constant or string argument directly */
 394
 395                 acpi_ps_get_next_simple_arg(&(walk_state->parser_state),
 396                                             GET_CURRENT_ARG_TYPE(walk_state->
 397                                                                  arg_types),
 398                                             op);
 399                 break;
 400
 401         case AML_INT_NAMEPATH_OP:       /* AML_NAMESTRING_ARG */
 402
 403                 status =
 404                     acpi_ps_get_next_namepath(walk_state,
 405                                               &(walk_state->parser_state), op,
 406                                               1);
 407                 if (ACPI_FAILURE(status)) {
 408                         return_ACPI_STATUS(status);
 409                 }
 410
 411                 walk_state->arg_types = 0;
 412                 break;
 413
 414         default:
 415                 /*
 416                  * Op is not a constant or string, append each argument to the Op
 417                  */
 418                 while (GET_CURRENT_ARG_TYPE(walk_state->arg_types)
 419                        && !walk_state->arg_count) {
 420                         walk_state->aml_offset =
 421                             (u32) ACPI_PTR_DIFF(walk_state->parser_state.aml,
 422                                                 walk_state->parser_state.
 423                                                 aml_start);
 424
 425                         status =
 426                             acpi_ps_get_next_arg(walk_state,
 427                                                  &(walk_state->parser_state),
 428                                                  GET_CURRENT_ARG_TYPE
 429                                                  (walk_state->arg_types), &arg);
 430                         if (ACPI_FAILURE(status)) {
 431                                 return_ACPI_STATUS(status);
 432                         }
 433
 434                         if (arg) {
 435                                 arg->common.aml_offset = walk_state->aml_offset;
 436                                 acpi_ps_append_arg(op, arg);
 437                         }
 438
 439                         INCREMENT_ARG_LIST(walk_state->arg_types);
 440                 }
 441
 442                 /* Special processing for certain opcodes */
 443
 444                 /* TBD (remove): Temporary mechanism to disable this code if needed */
 445
 446 #ifdef ACPI_ENABLE_MODULE_LEVEL_CODE
 447
 448                 if ((walk_state->pass_number <= ACPI_IMODE_LOAD_PASS1) &&
 449                     ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) == 0)) {
 450                         /*
 451                          * We want to skip If/Else/While constructs during Pass1 because we
 452                          * want to actually conditionally execute the code during Pass2.
 453                          *
 454                          * Except for disassembly, where we always want to walk the
 455                          * If/Else/While packages
 456                          */
 457                         switch (op->common.aml_opcode) {
 458                         case AML_IF_OP:
 459                         case AML_ELSE_OP:
 460                         case AML_WHILE_OP:
 461
 462                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 463                                                   "Pass1: Skipping an If/Else/While body\n"));
 464
 465                                 /* Skip body of if/else/while in pass 1 */
 466
 467                                 walk_state->parser_state.aml =
 468                                     walk_state->parser_state.pkg_end;
 469                                 walk_state->arg_count = 0;
 470                                 break;
 471
 472                         default:
 473                                 break;
 474                         }
 475                 }
 476 #endif
 477
 478                 switch (op->common.aml_opcode) {
 479                 case AML_METHOD_OP:
 480                         /*
 481                          * Skip parsing of control method because we don't have enough
 482                          * info in the first pass to parse it correctly.
 483                          *
 484                          * Save the length and address of the body
 485                          */
 486                         op->named.data = walk_state->parser_state.aml;
 487                         op->named.length = (u32)
 488                             (walk_state->parser_state.pkg_end -
 489                              walk_state->parser_state.aml);
 490
 491                         /* Skip body of method */
 492
 493                         walk_state->parser_state.aml =
 494                             walk_state->parser_state.pkg_end;
 495                         walk_state->arg_count = 0;
 496                         break;
 497
 498                 case AML_BUFFER_OP:
 499                 case AML_PACKAGE_OP:
 500                 case AML_VAR_PACKAGE_OP:
 501
 502                         if ((op->common.parent) &&
 503                             (op->common.parent->common.aml_opcode ==
 504                              AML_NAME_OP)
 505                             && (walk_state->pass_number <=
 506                                 ACPI_IMODE_LOAD_PASS2)) {
 507                                 /*
 508                                  * Skip parsing of Buffers and Packages because we don't have
 509                                  * enough info in the first pass to parse them correctly.
 510                                  */
 511                                 op->named.data = aml_op_start;
 512                                 op->named.length = (u32)
 513                                     (walk_state->parser_state.pkg_end -
 514                                      aml_op_start);
 515
 516                                 /* Skip body */
 517
 518                                 walk_state->parser_state.aml =
 519                                     walk_state->parser_state.pkg_end;
 520                                 walk_state->arg_count = 0;
 521                         }
 522                         break;
 523
 524                 case AML_WHILE_OP:
 525
 526                         if (walk_state->control_state) {
 527                                 walk_state->control_state->control.package_end =
 528                                     walk_state->parser_state.pkg_end;
 529                         }
 530                         break;
 531
 532                 default:
 533
 534                         /* No action for all other opcodes */
 535                         break;
 536                 }
 537
 538                 break;
 539         }
 540
 541         return_ACPI_STATUS(AE_OK);
 542 }
 543
 544 /*******************************************************************************
 545  *
 546  * FUNCTION:    acpi_ps_complete_op
 547  *
 548  * PARAMETERS:  walk_state          - Current state
 549  *              Op                  - Returned Op
 550  *              Status              - Parse status before complete Op
 551  *
 552  * RETURN:      Status
 553  *
 554  * DESCRIPTION: Complete Op
 555  *
 556  ******************************************************************************/
 557
 558 static acpi_status
 559 acpi_ps_complete_op(struct acpi_walk_state *walk_state,
 560                     union acpi_parse_object **op, acpi_status status)
 561 {
 562         acpi_status status2;
 563
 564         ACPI_FUNCTION_TRACE_PTR(ps_complete_op, walk_state);
 565
 566         /*
 567          * Finished one argument of the containing scope
 568          */
 569         walk_state->parser_state.scope->parse_scope.arg_count--;
 570
 571         /* Close this Op (will result in parse subtree deletion) */
 572
 573         status2 = acpi_ps_complete_this_op(walk_state, *op);
 574         if (ACPI_FAILURE(status2)) {
 575                 return_ACPI_STATUS(status2);
 576         }
 577
 578         *op = NULL;
 579
 580         switch (status) {
 581         case AE_OK:
 582                 break;
 583
 584         case AE_CTRL_TRANSFER:
 585
 586                 /* We are about to transfer to a called method */
 587
 588                 walk_state->prev_op = NULL;
 589                 walk_state->prev_arg_types = walk_state->arg_types;
 590                 return_ACPI_STATUS(status);
 591
 592         case AE_CTRL_END:
 593
 594                 acpi_ps_pop_scope(&(walk_state->parser_state), op,
 595                                   &walk_state->arg_types,
 596                                   &walk_state->arg_count);
 597
 598                 if (*op) {
 599                         walk_state->op = *op;
 600                         walk_state->op_info =
 601                             acpi_ps_get_opcode_info((*op)->common.aml_opcode);
 602                         walk_state->opcode = (*op)->common.aml_opcode;
 603
 604                         status = walk_state->ascending_callback(walk_state);
 605                         status =
 606                             acpi_ps_next_parse_state(walk_state, *op, status);
 607
 608                         status2 = acpi_ps_complete_this_op(walk_state, *op);
 609                         if (ACPI_FAILURE(status2)) {
 610                                 return_ACPI_STATUS(status2);
 611                         }
 612                 }
 613
 614                 status = AE_OK;
 615                 break;
 616
 617         case AE_CTRL_BREAK:
 618         case AE_CTRL_CONTINUE:
 619
 620                 /* Pop off scopes until we find the While */
 621
 622                 while (!(*op) || ((*op)->common.aml_opcode != AML_WHILE_OP)) {
 623                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 624                                           &walk_state->arg_types,
 625                                           &walk_state->arg_count);
 626                 }
 627
 628                 /* Close this iteration of the While loop */
 629
 630                 walk_state->op = *op;
 631                 walk_state->op_info =
 632                     acpi_ps_get_opcode_info((*op)->common.aml_opcode);
 633                 walk_state->opcode = (*op)->common.aml_opcode;
 634
 635                 status = walk_state->ascending_callback(walk_state);
 636                 status = acpi_ps_next_parse_state(walk_state, *op, status);
 637
 638                 status2 = acpi_ps_complete_this_op(walk_state, *op);
 639                 if (ACPI_FAILURE(status2)) {
 640                         return_ACPI_STATUS(status2);
 641                 }
 642
 643                 status = AE_OK;
 644                 break;
 645
 646         case AE_CTRL_TERMINATE:
 647
 648                 /* Clean up */
 649                 do {
 650                         if (*op) {
 651                                 status2 =
 652                                     acpi_ps_complete_this_op(walk_state, *op);
 653                                 if (ACPI_FAILURE(status2)) {
 654                                         return_ACPI_STATUS(status2);
 655                                 }
 656
 657                                 acpi_ut_delete_generic_state
 658                                     (acpi_ut_pop_generic_state
 659                                      (&walk_state->control_state));
 660                         }
 661
 662                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 663                                           &walk_state->arg_types,
 664                                           &walk_state->arg_count);
 665
 666                 } while (*op);
 667
 668                 return_ACPI_STATUS(AE_OK);
 669
 670         default:                /* All other non-AE_OK status */
 671
 672                 do {
 673                         if (*op) {
 674                                 status2 =
 675                                     acpi_ps_complete_this_op(walk_state, *op);
 676                                 if (ACPI_FAILURE(status2)) {
 677                                         return_ACPI_STATUS(status2);
 678                                 }
 679                         }
 680
 681                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 682                                           &walk_state->arg_types,
 683                                           &walk_state->arg_count);
 684
 685                 } while (*op);
 686
 687 #if 0
 688                 /*
 689                  * TBD: Cleanup parse ops on error
 690                  */
 691                 if (*op == NULL) {
 692                         acpi_ps_pop_scope(parser_state, op,
 693                                           &walk_state->arg_types,
 694                                           &walk_state->arg_count);
 695                 }
 696 #endif
 697                 walk_state->prev_op = NULL;
 698                 walk_state->prev_arg_types = walk_state->arg_types;
 699                 return_ACPI_STATUS(status);
 700         }
 701
 702         /* This scope complete? */
 703
 704         if (acpi_ps_has_completed_scope(&(walk_state->parser_state))) {
 705                 acpi_ps_pop_scope(&(walk_state->parser_state), op,
 706                                   &walk_state->arg_types,
 707                                   &walk_state->arg_count);
 708                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Popped scope, Op=%p\n", *op));
 709         } else {
 710                 *op = NULL;
 711         }
 712
 713         return_ACPI_STATUS(AE_OK);
 714 }
 715
 716 /*******************************************************************************
 717  *
 718  * FUNCTION:    acpi_ps_complete_final_op
 719  *
 720  * PARAMETERS:  walk_state          - Current state
 721  *              Op                  - Current Op
 722  *              Status              - Current parse status before complete last
 723  *                                    Op
 724  *
 725  * RETURN:      Status
 726  *
 727  * DESCRIPTION: Complete last Op.
 728  *
 729  ******************************************************************************/
 730
 731 static acpi_status
 732 acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
 733                           union acpi_parse_object *op, acpi_status status)
 734 {
 735         acpi_status status2;
 736
 737         ACPI_FUNCTION_TRACE_PTR(ps_complete_final_op, walk_state);
 738
 739         /*
 740          * Complete the last Op (if not completed), and clear the scope stack.
 741          * It is easily possible to end an AML "package" with an unbounded number
 742          * of open scopes (such as when several ASL blocks are closed with
 743          * sequential closing braces). We want to terminate each one cleanly.
 744          */
 745         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "AML package complete at Op %p\n",
 746                           op));
 747         do {
 748                 if (op) {
 749                         if (walk_state->ascending_callback != NULL) {
 750                                 walk_state->op = op;
 751                                 walk_state->op_info =
 752                                     acpi_ps_get_opcode_info(op->common.
 753                                                             aml_opcode);
 754                                 walk_state->opcode = op->common.aml_opcode;
 755
 756                                 status =
 757                                     walk_state->ascending_callback(walk_state);
 758                                 status =
 759                                     acpi_ps_next_parse_state(walk_state, op,
 760                                                              status);
 761                                 if (status == AE_CTRL_PENDING) {
 762                                         status =
 763                                             acpi_ps_complete_op(walk_state, &op,
 764                                                                 AE_OK);
 765                                         if (ACPI_FAILURE(status)) {
 766                                                 return_ACPI_STATUS(status);
 767                                         }
 768                                 }
 769
 770                                 if (status == AE_CTRL_TERMINATE) {
 771                                         status = AE_OK;
 772
 773                                         /* Clean up */
 774                                         do {
 775                                                 if (op) {
 776                                                         status2 =
 777                                                             acpi_ps_complete_this_op
 778                                                             (walk_state, op);
 779                                                         if (ACPI_FAILURE
 780                                                             (status2)) {
 781                                                                 return_ACPI_STATUS
 782                                                                     (status2);
 783                                                         }
 784                                                 }
 785
 786                                                 acpi_ps_pop_scope(&
 787                                                                   (walk_state->
 788                                                                    parser_state),
 789                                                                   &op,
 790                                                                   &walk_state->
 791                                                                   arg_types,
 792                                                                   &walk_state->
 793                                                                   arg_count);
 794
 795                                         } while (op);
 796
 797                                         return_ACPI_STATUS(status);
 798                                 }
 799
 800                                 else if (ACPI_FAILURE(status)) {
 801
 802                                         /* First error is most important */
 803
 804                                         (void)
 805                                             acpi_ps_complete_this_op(walk_state,
 806                                                                      op);
 807                                         return_ACPI_STATUS(status);
 808                                 }
 809                         }
 810
 811                         status2 = acpi_ps_complete_this_op(walk_state, op);
 812                         if (ACPI_FAILURE(status2)) {
 813                                 return_ACPI_STATUS(status2);
 814                         }
 815                 }
 816
 817                 acpi_ps_pop_scope(&(walk_state->parser_state), &op,
 818                                   &walk_state->arg_types,
 819                                   &walk_state->arg_count);
 820
 821         } while (op);
 822
 823         return_ACPI_STATUS(status);
 824 }
 825
 826 /*******************************************************************************
 827  *
 828  * FUNCTION:    acpi_ps_parse_loop
 829  *
 830  * PARAMETERS:  walk_state          - Current state
 831  *
 832  * RETURN:      Status
 833  *
 834  * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
 835  *              a tree of ops.
 836  *
 837  ******************************************************************************/
 838
 839 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
 840 {
 841         acpi_status status = AE_OK;
 842         union acpi_parse_object *op = NULL;     /* current op */
 843         struct acpi_parse_state *parser_state;
 844         u8 *aml_op_start = NULL;
 845
 846         ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);
 847
 848         if (walk_state->descending_callback == NULL) {
 849                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 850         }
 851
 852         parser_state = &walk_state->parser_state;
 853         walk_state->arg_types = 0;
 854
 855 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
 856
 857         if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
 858
 859                 /* We are restarting a preempted control method */
 860
 861                 if (acpi_ps_has_completed_scope(parser_state)) {
 862                         /*
 863                          * We must check if a predicate to an IF or WHILE statement
 864                          * was just completed
 865                          */
 866                         if ((parser_state->scope->parse_scope.op) &&
 867                             ((parser_state->scope->parse_scope.op->common.
 868                               aml_opcode == AML_IF_OP)
 869                              || (parser_state->scope->parse_scope.op->common.
 870                                  aml_opcode == AML_WHILE_OP))
 871                             && (walk_state->control_state)
 872                             && (walk_state->control_state->common.state ==
 873                                 ACPI_CONTROL_PREDICATE_EXECUTING)) {
 874                                 /*
 875                                  * A predicate was just completed, get the value of the
 876                                  * predicate and branch based on that value
 877                                  */
 878                                 walk_state->op = NULL;
 879                                 status =
 880                                     acpi_ds_get_predicate_value(walk_state,
 881                                                                 ACPI_TO_POINTER
 882                                                                 (TRUE));
 883                                 if (ACPI_FAILURE(status)
 884                                     && ((status & AE_CODE_MASK) !=
 885                                         AE_CODE_CONTROL)) {
 886                                         if (status == AE_AML_NO_RETURN_VALUE) {
 887                                                 ACPI_EXCEPTION((AE_INFO, status,
 888                                                                 "Invoked method did not return a value"));
 889
 890                                         }
 891
 892                                         ACPI_EXCEPTION((AE_INFO, status,
 893                                                         "GetPredicate Failed"));
 894                                         return_ACPI_STATUS(status);
 895                                 }
 896
 897                                 status =
 898                                     acpi_ps_next_parse_state(walk_state, op,
 899                                                              status);
 900                         }
 901
 902                         acpi_ps_pop_scope(parser_state, &op,
 903                                           &walk_state->arg_types,
 904                                           &walk_state->arg_count);
 905                         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 906                                           "Popped scope, Op=%p\n", op));
 907                 } else if (walk_state->prev_op) {
 908
 909                         /* We were in the middle of an op */
 910
 911                         op = walk_state->prev_op;
 912                         walk_state->arg_types = walk_state->prev_arg_types;
 913                 }
 914         }
 915 #endif
 916
 917         /* Iterative parsing loop, while there is more AML to process: */
 918
 919         while ((parser_state->aml < parser_state->aml_end) || (op)) {
 920                 aml_op_start = parser_state->aml;
 921                 if (!op) {
 922                         status =
 923                             acpi_ps_create_op(walk_state, aml_op_start, &op);
 924                         if (ACPI_FAILURE(status)) {
 925                                 if (status == AE_CTRL_PARSE_CONTINUE) {
 926                                         continue;
 927                                 }
 928
 929                                 if (status == AE_CTRL_PARSE_PENDING) {
 930                                         status = AE_OK;
 931                                 }
 932
 933                                 status =
 934                                     acpi_ps_complete_op(walk_state, &op,
 935                                                         status);
 936                                 if (ACPI_FAILURE(status)) {
 937                                         return_ACPI_STATUS(status);
 938                                 }
 939
 940                                 continue;
 941                         }
 942
 943                         op->common.aml_offset = walk_state->aml_offset;
 944
 945                         if (walk_state->op_info) {
 946                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 947                                                   "Opcode %4.4X [%s] Op %p Aml %p AmlOffset %5.5X\n",
 948                                                   (u32) op->common.aml_opcode,
 949                                                   walk_state->op_info->name, op,
 950                                                   parser_state->aml,
 951                                                   op->common.aml_offset));
 952                         }
 953                 }
 954
 955                 /*
 956                  * Start arg_count at zero because we don't know if there are
 957                  * any args yet
 958                  */
 959                 walk_state->arg_count = 0;
 960
 961                 /* Are there any arguments that must be processed? */
 962
 963                 if (walk_state->arg_types) {
 964
 965                         /* Get arguments */
 966
 967                         status =
 968                             acpi_ps_get_arguments(walk_state, aml_op_start, op);
 969                         if (ACPI_FAILURE(status)) {
 970                                 status =
 971                                     acpi_ps_complete_op(walk_state, &op,
 972                                                         status);
 973                                 if (ACPI_FAILURE(status)) {
 974                                         return_ACPI_STATUS(status);
 975                                 }
 976
 977                                 continue;
 978                         }
 979                 }
 980
 981                 /* Check for arguments that need to be processed */
 982
 983                 if (walk_state->arg_count) {
 984                         /*
 985                          * There are arguments (complex ones), push Op and
 986                          * prepare for argument
 987                          */
 988                         status = acpi_ps_push_scope(parser_state, op,
 989                                                     walk_state->arg_types,
 990                                                     walk_state->arg_count);
 991                         if (ACPI_FAILURE(status)) {
 992                                 status =
 993                                     acpi_ps_complete_op(walk_state, &op,
 994                                                         status);
 995                                 if (ACPI_FAILURE(status)) {
 996                                         return_ACPI_STATUS(status);
 997                                 }
 998
 999                                 continue;
1000                         }
1001
1002                         op = NULL;
1003                         continue;
1004                 }
1005
1006                 /*
1007                  * All arguments have been processed -- Op is complete,
1008                  * prepare for next
1009                  */
1010                 walk_state->op_info =
1011                     acpi_ps_get_opcode_info(op->common.aml_opcode);
1012                 if (walk_state->op_info->flags & AML_NAMED) {
1013                         if (acpi_gbl_depth) {
1014                                 acpi_gbl_depth--;
1015                         }
1016
1017                         if (op->common.aml_opcode == AML_REGION_OP ||
1018                             op->common.aml_opcode == AML_DATA_REGION_OP) {
1019                                 /*
1020                                  * Skip parsing of control method or opregion body,
1021                                  * because we don't have enough info in the first pass
1022                                  * to parse them correctly.
1023                                  *
1024                                  * Completed parsing an op_region declaration, we now
1025                                  * know the length.
1026                                  */
1027                                 op->named.length =
1028                                     (u32) (parser_state->aml - op->named.data);
1029                         }
1030                 }
1031
1032                 if (walk_state->op_info->flags & AML_CREATE) {
1033                         /*
1034                          * Backup to beginning of create_xXXfield declaration (1 for
1035                          * Opcode)
1036                          *
1037                          * body_length is unknown until we parse the body
1038                          */
1039                         op->named.length =
1040                             (u32) (parser_state->aml - op->named.data);
1041                 }
1042
1043                 /* This op complete, notify the dispatcher */
1044
1045                 if (walk_state->ascending_callback != NULL) {
1046                         walk_state->op = op;
1047                         walk_state->opcode = op->common.aml_opcode;
1048
1049                         status = walk_state->ascending_callback(walk_state);
1050                         status =
1051                             acpi_ps_next_parse_state(walk_state, op, status);
1052                         if (status == AE_CTRL_PENDING) {
1053                                 status = AE_OK;
1054                         }
1055                 }
1056
1057                 status = acpi_ps_complete_op(walk_state, &op, status);
1058                 if (ACPI_FAILURE(status)) {
1059                         return_ACPI_STATUS(status);
1060                 }
1061
1062         }                       /* while parser_state->Aml */
1063
1064         status = acpi_ps_complete_final_op(walk_state, op, status);
1065         return_ACPI_STATUS(status);
1066 }