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