1 /****************************************************************************** 2 * 3 * Module Name: dtutils.c - Utility routines for the data table compiler 4 * 5 *****************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2022, Intel Corp. 9 * All rights reserved. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions, and the following disclaimer, 16 * without modification. 17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 18 * substantially similar to the "NO WARRANTY" disclaimer below 19 * ("Disclaimer") and any redistribution must be conditioned upon 20 * including a substantially similar Disclaimer requirement for further 21 * binary redistribution. 22 * 3. Neither the names of the above-listed copyright holders nor the names 23 * of any contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * Alternatively, this software may be distributed under the terms of the 27 * GNU General Public License ("GPL") version 2 as published by the Free 28 * Software Foundation. 29 * 30 * NO WARRANTY 31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 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 #include "aslcompiler.h" 45 #include "actables.h" 46 47 #define _COMPONENT DT_COMPILER 48 ACPI_MODULE_NAME ("dtutils") 49 50 /* Local prototypes */ 51 52 static void 53 DtSum ( 54 DT_SUBTABLE *Subtable, 55 void *Context, 56 void *ReturnValue); 57 58 59 /****************************************************************************** 60 * 61 * FUNCTION: DtError 62 * 63 * PARAMETERS: Level - Seriousness (Warning/error, etc.) 64 * MessageId - Index into global message buffer 65 * Op - Parse node where error happened 66 * ExtraMessage - additional error message 67 * 68 * RETURN: None 69 * 70 * DESCRIPTION: Common error interface for data table compiler 71 * 72 *****************************************************************************/ 73 74 void 75 DtError ( 76 UINT8 Level, 77 UINT16 MessageId, 78 DT_FIELD *FieldObject, 79 char *ExtraMessage) 80 { 81 UINT32 Line = 0; 82 83 84 /* Field object could be NULL */ 85 86 if (FieldObject) 87 { 88 Line = FieldObject->Line; 89 } 90 91 /* Check if user wants to ignore this exception */ 92 93 if (AslIsExceptionIgnored (AslGbl_Files[ASL_FILE_INPUT].Filename, 94 Line, Level, MessageId)) 95 { 96 return; 97 } 98 99 if (FieldObject) 100 { 101 AslCommonError (Level, MessageId, 102 FieldObject->Line, 103 FieldObject->Line, 104 FieldObject->ByteOffset, 105 FieldObject->Column, 106 AslGbl_Files[ASL_FILE_INPUT].Filename, ExtraMessage); 107 } 108 else 109 { 110 AslCommonError (Level, MessageId, 0, 111 0, 0, 0, 0, ExtraMessage); 112 } 113 } 114 115 116 /****************************************************************************** 117 * 118 * FUNCTION: DtNameError 119 * 120 * PARAMETERS: Level - Seriousness (Warning/error, etc.) 121 * MessageId - Index into global message buffer 122 * Op - Parse node where error happened 123 * ExtraMessage - additional error message 124 * 125 * RETURN: None 126 * 127 * DESCRIPTION: Error interface for named objects 128 * 129 *****************************************************************************/ 130 131 void 132 DtNameError ( 133 UINT8 Level, 134 UINT16 MessageId, 135 DT_FIELD *FieldObject, 136 char *ExtraMessage) 137 { 138 139 switch (Level) 140 { 141 case ASL_WARNING2: 142 case ASL_WARNING3: 143 144 if (AslGbl_WarningLevel < Level) 145 { 146 return; 147 } 148 break; 149 150 default: 151 152 break; 153 } 154 155 if (FieldObject) 156 { 157 AslCommonError (Level, MessageId, 158 FieldObject->Line, 159 FieldObject->Line, 160 FieldObject->ByteOffset, 161 FieldObject->NameColumn, 162 AslGbl_Files[ASL_FILE_INPUT].Filename, ExtraMessage); 163 } 164 else 165 { 166 AslCommonError (Level, MessageId, 0, 167 0, 0, 0, 0, ExtraMessage); 168 } 169 } 170 171 172 /******************************************************************************* 173 * 174 * FUNCTION: DtFatal 175 * 176 * PARAMETERS: None 177 * 178 * RETURN: None 179 * 180 * DESCRIPTION: Dump the error log and abort the compiler. Used for serious 181 * compile or I/O errors 182 * 183 ******************************************************************************/ 184 185 void 186 DtFatal ( 187 UINT16 MessageId, 188 DT_FIELD *FieldObject, 189 char *ExtraMessage) 190 { 191 192 DtError (ASL_ERROR, MessageId, FieldObject, ExtraMessage); 193 194 /* 195 * TBD: remove this entire function, DtFatal 196 * 197 * We cannot abort the compiler on error, because we may be compiling a 198 * list of files. We must move on to the next file. 199 */ 200 #ifdef __OBSOLETE 201 CmCleanupAndExit (); 202 exit (1); 203 #endif 204 } 205 206 207 /******************************************************************************* 208 * 209 * FUNCTION: DtDoConstant 210 * 211 * PARAMETERS: String - Only hex constants are supported, 212 * regardless of whether the 0x prefix 213 * is used 214 * 215 * RETURN: Converted Integer 216 * 217 * DESCRIPTION: Convert a string to an integer, with overflow/error checking. 218 * 219 ******************************************************************************/ 220 221 UINT64 222 DtDoConstant ( 223 char *String) 224 { 225 UINT64 ConvertedInteger; 226 227 228 /* 229 * TBD: The ImplicitStrtoul64 function does not report overflow 230 * conditions. The input string is simply truncated. If it is 231 * desired to report overflow to the table compiler, this should 232 * somehow be added here. Note: integers that are prefixed with 0x 233 * or not are both hex integers. 234 */ 235 ConvertedInteger = AcpiUtImplicitStrtoul64 (String); 236 return (ConvertedInteger); 237 } 238 239 /****************************************************************************** 240 * 241 * FUNCTION: DtGetFieldValue 242 * 243 * PARAMETERS: Field - Current field list pointer 244 * 245 * RETURN: Field value 246 * 247 * DESCRIPTION: Get field value 248 * 249 *****************************************************************************/ 250 251 char * 252 DtGetFieldValue ( 253 DT_FIELD *Field) 254 { 255 if (!Field) 256 { 257 return (NULL); 258 } 259 260 return (Field->Value); 261 } 262 263 264 /****************************************************************************** 265 * 266 * FUNCTION: DtGetFieldType 267 * 268 * PARAMETERS: Info - Data table info 269 * 270 * RETURN: Field type 271 * 272 * DESCRIPTION: Get field type 273 * 274 *****************************************************************************/ 275 276 UINT8 277 DtGetFieldType ( 278 ACPI_DMTABLE_INFO *Info) 279 { 280 UINT8 Type; 281 282 283 /* DT_FLAG means that this is the start of a block of flag bits */ 284 /* TBD - we can make these a separate opcode later */ 285 286 if (Info->Flags & DT_FLAG) 287 { 288 return (DT_FIELD_TYPE_FLAGS_INTEGER); 289 } 290 291 /* Type is based upon the opcode for this field in the info table */ 292 293 switch (Info->Opcode) 294 { 295 case ACPI_DMT_FLAG0: 296 case ACPI_DMT_FLAG1: 297 case ACPI_DMT_FLAG2: 298 case ACPI_DMT_FLAG3: 299 case ACPI_DMT_FLAG4: 300 case ACPI_DMT_FLAG5: 301 case ACPI_DMT_FLAG6: 302 case ACPI_DMT_FLAG7: 303 case ACPI_DMT_FLAGS0: 304 case ACPI_DMT_FLAGS1: 305 case ACPI_DMT_FLAGS2: 306 case ACPI_DMT_FLAGS8_2: 307 case ACPI_DMT_FLAGS4: 308 case ACPI_DMT_FLAGS4_0: 309 case ACPI_DMT_FLAGS4_4: 310 case ACPI_DMT_FLAGS4_8: 311 case ACPI_DMT_FLAGS4_12: 312 case ACPI_DMT_FLAGS16_16: 313 314 Type = DT_FIELD_TYPE_FLAG; 315 break; 316 317 case ACPI_DMT_NAME4: 318 case ACPI_DMT_SIG: 319 case ACPI_DMT_NAME6: 320 case ACPI_DMT_NAME8: 321 case ACPI_DMT_STRING: 322 case ACPI_DMT_IVRS_UNTERMINATED_STRING: 323 324 Type = DT_FIELD_TYPE_STRING; 325 break; 326 327 case ACPI_DMT_BUFFER: 328 case ACPI_DMT_RAW_BUFFER: 329 case ACPI_DMT_BUF7: 330 case ACPI_DMT_BUF10: 331 case ACPI_DMT_BUF12: 332 case ACPI_DMT_BUF16: 333 case ACPI_DMT_BUF18: 334 case ACPI_DMT_BUF128: 335 case ACPI_DMT_PCI_PATH: 336 case ACPI_DMT_PMTT_VENDOR: 337 338 Type = DT_FIELD_TYPE_BUFFER; 339 break; 340 341 case ACPI_DMT_GAS: 342 case ACPI_DMT_HESTNTFY: 343 case ACPI_DMT_IORTMEM: 344 345 Type = DT_FIELD_TYPE_INLINE_SUBTABLE; 346 break; 347 348 case ACPI_DMT_UNICODE: 349 case ACPI_DMT_WPBT_UNICODE: 350 351 Type = DT_FIELD_TYPE_UNICODE; 352 break; 353 354 case ACPI_DMT_UUID: 355 356 Type = DT_FIELD_TYPE_UUID; 357 break; 358 359 case ACPI_DMT_DEVICE_PATH: 360 361 Type = DT_FIELD_TYPE_DEVICE_PATH; 362 break; 363 364 case ACPI_DMT_LABEL: 365 366 Type = DT_FIELD_TYPE_LABEL; 367 break; 368 369 default: 370 371 Type = DT_FIELD_TYPE_INTEGER; 372 break; 373 } 374 375 return (Type); 376 } 377 378 379 /****************************************************************************** 380 * 381 * FUNCTION: DtGetBufferLength 382 * 383 * PARAMETERS: Buffer - List of integers, 384 * for example "10 3A 4F 2E" 385 * 386 * RETURN: Count of integer 387 * 388 * DESCRIPTION: Get length of bytes needed to store the integers 389 * 390 *****************************************************************************/ 391 392 UINT32 393 DtGetBufferLength ( 394 char *Buffer) 395 { 396 UINT32 ByteLength = 0; 397 398 399 while (*Buffer) 400 { 401 if (*Buffer == ' ') 402 { 403 ByteLength++; 404 405 while (*Buffer == ' ') 406 { 407 Buffer++; 408 } 409 } 410 411 Buffer++; 412 } 413 414 return (++ByteLength); 415 } 416 417 418 /****************************************************************************** 419 * 420 * FUNCTION: DtGetFieldLength 421 * 422 * PARAMETERS: Field - Current field 423 * Info - Data table info 424 * 425 * RETURN: Field length 426 * 427 * DESCRIPTION: Get length of bytes needed to compile the field 428 * 429 * Note: This function must remain in sync with AcpiDmDumpTable. 430 * 431 *****************************************************************************/ 432 433 UINT32 434 DtGetFieldLength ( 435 DT_FIELD *Field, 436 ACPI_DMTABLE_INFO *Info) 437 { 438 UINT32 ByteLength = 0; 439 char *Value; 440 441 442 /* Length is based upon the opcode for this field in the info table */ 443 444 switch (Info->Opcode) 445 { 446 case ACPI_DMT_FLAG0: 447 case ACPI_DMT_FLAG1: 448 case ACPI_DMT_FLAG2: 449 case ACPI_DMT_FLAG3: 450 case ACPI_DMT_FLAG4: 451 case ACPI_DMT_FLAG5: 452 case ACPI_DMT_FLAG6: 453 case ACPI_DMT_FLAG7: 454 case ACPI_DMT_FLAGS0: 455 case ACPI_DMT_FLAGS1: 456 case ACPI_DMT_FLAGS2: 457 case ACPI_DMT_FLAGS8_2: 458 case ACPI_DMT_FLAGS4: 459 case ACPI_DMT_FLAGS4_0: 460 case ACPI_DMT_FLAGS4_4: 461 case ACPI_DMT_FLAGS4_8: 462 case ACPI_DMT_FLAGS4_12: 463 case ACPI_DMT_FLAGS16_16: 464 case ACPI_DMT_LABEL: 465 case ACPI_DMT_EXTRA_TEXT: 466 467 ByteLength = 0; 468 break; 469 470 case ACPI_DMT_UINT8: 471 case ACPI_DMT_CHKSUM: 472 case ACPI_DMT_SPACEID: 473 case ACPI_DMT_ACCWIDTH: 474 case ACPI_DMT_CEDT: 475 case ACPI_DMT_IVRS: 476 case ACPI_DMT_IVRS_DE: 477 case ACPI_DMT_GTDT: 478 case ACPI_DMT_MADT: 479 case ACPI_DMT_NHLT1: 480 case ACPI_DMT_NHLT1a: 481 case ACPI_DMT_NHLT1b: 482 case ACPI_DMT_NHLT1c: 483 case ACPI_DMT_NHLT1d: 484 case ACPI_DMT_NHLT1f: 485 case ACPI_DMT_PCCT: 486 case ACPI_DMT_PMTT: 487 case ACPI_DMT_PPTT: 488 case ACPI_DMT_RGRT: 489 case ACPI_DMT_SDEV: 490 case ACPI_DMT_SRAT: 491 case ACPI_DMT_AEST: 492 case ACPI_DMT_AEST_RES: 493 case ACPI_DMT_AEST_XFACE: 494 case ACPI_DMT_AEST_XRUPT: 495 case ACPI_DMT_ASF: 496 case ACPI_DMT_HESTNTYP: 497 case ACPI_DMT_FADTPM: 498 case ACPI_DMT_EINJACT: 499 case ACPI_DMT_EINJINST: 500 case ACPI_DMT_ERSTACT: 501 case ACPI_DMT_ERSTINST: 502 case ACPI_DMT_DMAR_SCOPE: 503 case ACPI_DMT_VIOT: 504 505 ByteLength = 1; 506 break; 507 508 case ACPI_DMT_UINT16: 509 case ACPI_DMT_DMAR: 510 case ACPI_DMT_HEST: 511 case ACPI_DMT_HMAT: 512 case ACPI_DMT_NFIT: 513 case ACPI_DMT_NHLT1e: 514 case ACPI_DMT_PCI_PATH: 515 case ACPI_DMT_PHAT: 516 517 ByteLength = 2; 518 break; 519 520 case ACPI_DMT_UINT24: 521 522 ByteLength = 3; 523 break; 524 525 case ACPI_DMT_UINT32: 526 case ACPI_DMT_AEST_CACHE: 527 case ACPI_DMT_AEST_GIC: 528 case ACPI_DMT_NAME4: 529 case ACPI_DMT_SIG: 530 case ACPI_DMT_LPIT: 531 case ACPI_DMT_TPM2: 532 533 ByteLength = 4; 534 break; 535 536 case ACPI_DMT_UINT40: 537 538 ByteLength = 5; 539 break; 540 541 case ACPI_DMT_UINT48: 542 case ACPI_DMT_NAME6: 543 544 ByteLength = 6; 545 break; 546 547 case ACPI_DMT_UINT56: 548 case ACPI_DMT_BUF7: 549 550 ByteLength = 7; 551 break; 552 553 case ACPI_DMT_UINT64: 554 case ACPI_DMT_NAME8: 555 556 ByteLength = 8; 557 break; 558 559 case ACPI_DMT_STRING: 560 561 Value = DtGetFieldValue (Field); 562 if (Value) 563 { 564 ByteLength = strlen (Value) + 1; 565 } 566 else 567 { /* At this point, this is a fatal error */ 568 569 snprintf (AslGbl_MsgBuffer, sizeof(AslGbl_MsgBuffer), "Expected \"%s\"", Info->Name); 570 DtFatal (ASL_MSG_COMPILER_INTERNAL, NULL, AslGbl_MsgBuffer); 571 return (0); 572 } 573 break; 574 575 case ACPI_DMT_IVRS_UNTERMINATED_STRING: 576 577 Value = DtGetFieldValue (Field); 578 if (Value) 579 { 580 ByteLength = strlen (Value); 581 } 582 else 583 { /* At this point, this is a fatal error */ 584 585 snprintf (AslGbl_MsgBuffer, sizeof(AslGbl_MsgBuffer), "Expected \"%s\"", Info->Name); 586 DtFatal (ASL_MSG_COMPILER_INTERNAL, NULL, AslGbl_MsgBuffer); 587 return (0); 588 } 589 break; 590 591 case ACPI_DMT_GAS: 592 593 ByteLength = sizeof (ACPI_GENERIC_ADDRESS); 594 break; 595 596 case ACPI_DMT_HESTNTFY: 597 598 ByteLength = sizeof (ACPI_HEST_NOTIFY); 599 break; 600 601 case ACPI_DMT_IORTMEM: 602 603 ByteLength = sizeof (ACPI_IORT_MEMORY_ACCESS); 604 break; 605 606 case ACPI_DMT_BUFFER: 607 case ACPI_DMT_RAW_BUFFER: 608 case ACPI_DMT_PMTT_VENDOR: 609 610 Value = DtGetFieldValue (Field); 611 if (Value) 612 { 613 ByteLength = DtGetBufferLength (Value); 614 } 615 else 616 { /* At this point, this is a fatal error */ 617 618 snprintf (AslGbl_MsgBuffer, sizeof(AslGbl_MsgBuffer), "Expected \"%s\"", Info->Name); 619 DtFatal (ASL_MSG_COMPILER_INTERNAL, NULL, AslGbl_MsgBuffer); 620 return (0); 621 } 622 break; 623 624 case ACPI_DMT_BUF10: 625 626 ByteLength = 10; 627 break; 628 629 case ACPI_DMT_BUF12: 630 631 ByteLength = 12; 632 break; 633 634 case ACPI_DMT_BUF16: 635 case ACPI_DMT_UUID: 636 637 ByteLength = 16; 638 break; 639 640 case ACPI_DMT_BUF18: 641 642 ByteLength = 18; 643 break; 644 645 case ACPI_DMT_BUF128: 646 647 ByteLength = 128; 648 break; 649 650 case ACPI_DMT_UNICODE: 651 case ACPI_DMT_WPBT_UNICODE: 652 653 Value = DtGetFieldValue (Field); 654 655 /* TBD: error if Value is NULL? (as below?) */ 656 657 ByteLength = (strlen (Value) + 1) * sizeof (UINT16); 658 break; 659 660 default: 661 662 DtFatal (ASL_MSG_COMPILER_INTERNAL, Field, "Invalid table opcode"); 663 return (0); 664 } 665 666 return (ByteLength); 667 } 668 669 670 /****************************************************************************** 671 * 672 * FUNCTION: DtSum 673 * 674 * PARAMETERS: DT_WALK_CALLBACK: 675 * Subtable - Subtable 676 * Context - Unused 677 * ReturnValue - Store the checksum of subtable 678 * 679 * RETURN: Status 680 * 681 * DESCRIPTION: Get the checksum of subtable 682 * 683 *****************************************************************************/ 684 685 static void 686 DtSum ( 687 DT_SUBTABLE *Subtable, 688 void *Context, 689 void *ReturnValue) 690 { 691 UINT8 Checksum; 692 UINT8 *Sum = ReturnValue; 693 694 695 Checksum = AcpiTbChecksum (Subtable->Buffer, Subtable->Length); 696 *Sum = (UINT8) (*Sum + Checksum); 697 } 698 699 700 /****************************************************************************** 701 * 702 * FUNCTION: DtSetTableChecksum 703 * 704 * PARAMETERS: ChecksumPointer - Where to return the checksum 705 * 706 * RETURN: None 707 * 708 * DESCRIPTION: Set checksum of the whole data table into the checksum field 709 * 710 *****************************************************************************/ 711 712 void 713 DtSetTableChecksum ( 714 UINT8 *ChecksumPointer) 715 { 716 UINT8 Checksum = 0; 717 UINT8 OldSum; 718 719 720 DtWalkTableTree (AslGbl_RootTable, DtSum, NULL, &Checksum); 721 722 OldSum = *ChecksumPointer; 723 Checksum = (UINT8) (Checksum - OldSum); 724 725 /* Compute the final checksum */ 726 727 Checksum = (UINT8) (0 - Checksum); 728 *ChecksumPointer = Checksum; 729 } 730 731 732 /****************************************************************************** 733 * 734 * FUNCTION: DtSetTableLength 735 * 736 * PARAMETERS: None 737 * 738 * RETURN: None 739 * 740 * DESCRIPTION: Walk the subtables and set all the length fields 741 * 742 *****************************************************************************/ 743 744 void 745 DtSetTableLength ( 746 void) 747 { 748 DT_SUBTABLE *ParentTable; 749 DT_SUBTABLE *ChildTable; 750 751 752 ParentTable = AslGbl_RootTable; 753 ChildTable = NULL; 754 755 if (!ParentTable) 756 { 757 return; 758 } 759 760 DtSetSubtableLength (ParentTable); 761 762 while (1) 763 { 764 ChildTable = DtGetNextSubtable (ParentTable, ChildTable); 765 if (ChildTable) 766 { 767 if (ChildTable->LengthField) 768 { 769 DtSetSubtableLength (ChildTable); 770 } 771 772 if (ChildTable->Child) 773 { 774 ParentTable = ChildTable; 775 ChildTable = NULL; 776 } 777 else 778 { 779 ParentTable->TotalLength += ChildTable->TotalLength; 780 if (ParentTable->LengthField) 781 { 782 DtSetSubtableLength (ParentTable); 783 } 784 } 785 } 786 else 787 { 788 ChildTable = ParentTable; 789 790 if (ChildTable == AslGbl_RootTable) 791 { 792 break; 793 } 794 795 ParentTable = DtGetParentSubtable (ParentTable); 796 797 ParentTable->TotalLength += ChildTable->TotalLength; 798 if (ParentTable->LengthField) 799 { 800 DtSetSubtableLength (ParentTable); 801 } 802 } 803 } 804 } 805 806 807 /****************************************************************************** 808 * 809 * FUNCTION: DtWalkTableTree 810 * 811 * PARAMETERS: StartTable - Subtable in the tree where walking begins 812 * UserFunction - Called during the walk 813 * Context - Passed to user function 814 * ReturnValue - The return value of UserFunction 815 * 816 * RETURN: None 817 * 818 * DESCRIPTION: Performs a depth-first walk of the subtable tree 819 * 820 *****************************************************************************/ 821 822 void 823 DtWalkTableTree ( 824 DT_SUBTABLE *StartTable, 825 DT_WALK_CALLBACK UserFunction, 826 void *Context, 827 void *ReturnValue) 828 { 829 DT_SUBTABLE *ParentTable; 830 DT_SUBTABLE *ChildTable; 831 832 833 ParentTable = StartTable; 834 ChildTable = NULL; 835 836 if (!ParentTable) 837 { 838 return; 839 } 840 841 UserFunction (ParentTable, Context, ReturnValue); 842 843 while (1) 844 { 845 ChildTable = DtGetNextSubtable (ParentTable, ChildTable); 846 if (ChildTable) 847 { 848 UserFunction (ChildTable, Context, ReturnValue); 849 850 if (ChildTable->Child) 851 { 852 ParentTable = ChildTable; 853 ChildTable = NULL; 854 } 855 } 856 else 857 { 858 ChildTable = ParentTable; 859 if (ChildTable == AslGbl_RootTable) 860 { 861 break; 862 } 863 864 ParentTable = DtGetParentSubtable (ParentTable); 865 866 if (ChildTable->Peer == StartTable) 867 { 868 break; 869 } 870 } 871 } 872 } 873