dtutils.c revision 1.22 1 /******************************************************************************
2 *
3 * Module Name: dtutils.c - Utility routines for the data table compiler
4 *
5 *****************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2023, 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_MPAM_LOCATOR:
480 case ACPI_DMT_NHLT1:
481 case ACPI_DMT_NHLT1a:
482 case ACPI_DMT_NHLT1b:
483 case ACPI_DMT_NHLT1c:
484 case ACPI_DMT_NHLT1d:
485 case ACPI_DMT_NHLT1f:
486 case ACPI_DMT_PCCT:
487 case ACPI_DMT_PMTT:
488 case ACPI_DMT_PPTT:
489 case ACPI_DMT_RGRT:
490 case ACPI_DMT_SDEV:
491 case ACPI_DMT_SRAT:
492 case ACPI_DMT_AEST:
493 case ACPI_DMT_AEST_RES:
494 case ACPI_DMT_AEST_XFACE:
495 case ACPI_DMT_AEST_XRUPT:
496 case ACPI_DMT_ASF:
497 case ACPI_DMT_CDAT:
498 case ACPI_DMT_HESTNTYP:
499 case ACPI_DMT_FADTPM:
500 case ACPI_DMT_EINJACT:
501 case ACPI_DMT_EINJINST:
502 case ACPI_DMT_ERSTACT:
503 case ACPI_DMT_ERSTINST:
504 case ACPI_DMT_DMAR_SCOPE:
505 case ACPI_DMT_VIOT:
506
507 ByteLength = 1;
508 break;
509
510 case ACPI_DMT_ASPT:
511 case ACPI_DMT_UINT16:
512 case ACPI_DMT_DMAR:
513 case ACPI_DMT_HEST:
514 case ACPI_DMT_HMAT:
515 case ACPI_DMT_NFIT:
516 case ACPI_DMT_NHLT1e:
517 case ACPI_DMT_PCI_PATH:
518 case ACPI_DMT_PHAT:
519
520 ByteLength = 2;
521 break;
522
523 case ACPI_DMT_UINT24:
524
525 ByteLength = 3;
526 break;
527
528 case ACPI_DMT_UINT32:
529 case ACPI_DMT_AEST_CACHE:
530 case ACPI_DMT_AEST_GIC:
531 case ACPI_DMT_NAME4:
532 case ACPI_DMT_SIG:
533 case ACPI_DMT_LPIT:
534 case ACPI_DMT_TPM2:
535
536 ByteLength = 4;
537 break;
538
539 case ACPI_DMT_UINT40:
540
541 ByteLength = 5;
542 break;
543
544 case ACPI_DMT_UINT48:
545 case ACPI_DMT_NAME6:
546
547 ByteLength = 6;
548 break;
549
550 case ACPI_DMT_UINT56:
551 case ACPI_DMT_BUF7:
552
553 ByteLength = 7;
554 break;
555
556 case ACPI_DMT_UINT64:
557 case ACPI_DMT_NAME8:
558
559 ByteLength = 8;
560 break;
561
562 case ACPI_DMT_STRING:
563
564 Value = DtGetFieldValue (Field);
565 if (Value)
566 {
567 ByteLength = strlen (Value) + 1;
568 }
569 else
570 { /* At this point, this is a fatal error */
571
572 snprintf (AslGbl_MsgBuffer, sizeof(AslGbl_MsgBuffer), "Expected \"%s\"", Info->Name);
573 DtFatal (ASL_MSG_COMPILER_INTERNAL, NULL, AslGbl_MsgBuffer);
574 return (0);
575 }
576 break;
577
578 case ACPI_DMT_IVRS_UNTERMINATED_STRING:
579
580 Value = DtGetFieldValue (Field);
581 if (Value)
582 {
583 ByteLength = strlen (Value);
584 }
585 else
586 { /* At this point, this is a fatal error */
587
588 snprintf (AslGbl_MsgBuffer, sizeof(AslGbl_MsgBuffer), "Expected \"%s\"", Info->Name);
589 DtFatal (ASL_MSG_COMPILER_INTERNAL, NULL, AslGbl_MsgBuffer);
590 return (0);
591 }
592 break;
593
594 case ACPI_DMT_GAS:
595
596 ByteLength = sizeof (ACPI_GENERIC_ADDRESS);
597 break;
598
599 case ACPI_DMT_HESTNTFY:
600
601 ByteLength = sizeof (ACPI_HEST_NOTIFY);
602 break;
603
604 case ACPI_DMT_IORTMEM:
605
606 ByteLength = sizeof (ACPI_IORT_MEMORY_ACCESS);
607 break;
608
609 case ACPI_DMT_BUFFER:
610 case ACPI_DMT_RAW_BUFFER:
611 case ACPI_DMT_PMTT_VENDOR:
612
613 Value = DtGetFieldValue (Field);
614 if (Value)
615 {
616 ByteLength = DtGetBufferLength (Value);
617 }
618 else
619 { /* At this point, this is a fatal error */
620
621 snprintf (AslGbl_MsgBuffer, sizeof(AslGbl_MsgBuffer), "Expected \"%s\"", Info->Name);
622 DtFatal (ASL_MSG_COMPILER_INTERNAL, NULL, AslGbl_MsgBuffer);
623 return (0);
624 }
625 break;
626
627 case ACPI_DMT_BUF10:
628
629 ByteLength = 10;
630 break;
631
632 case ACPI_DMT_BUF12:
633
634 ByteLength = 12;
635 break;
636
637 case ACPI_DMT_BUF16:
638 case ACPI_DMT_UUID:
639
640 ByteLength = 16;
641 break;
642
643 case ACPI_DMT_BUF18:
644
645 ByteLength = 18;
646 break;
647
648 case ACPI_DMT_BUF128:
649
650 ByteLength = 128;
651 break;
652
653 case ACPI_DMT_UNICODE:
654 case ACPI_DMT_WPBT_UNICODE:
655
656 Value = DtGetFieldValue (Field);
657
658 /* TBD: error if Value is NULL? (as below?) */
659
660 ByteLength = (strlen (Value) + 1) * sizeof (UINT16);
661 break;
662
663 default:
664
665 DtFatal (ASL_MSG_COMPILER_INTERNAL, Field, "Invalid table opcode");
666 return (0);
667 }
668
669 return (ByteLength);
670 }
671
672
673 /******************************************************************************
674 *
675 * FUNCTION: DtSum
676 *
677 * PARAMETERS: DT_WALK_CALLBACK:
678 * Subtable - Subtable
679 * Context - Unused
680 * ReturnValue - Store the checksum of subtable
681 *
682 * RETURN: Status
683 *
684 * DESCRIPTION: Get the checksum of subtable
685 *
686 *****************************************************************************/
687
688 static void
689 DtSum (
690 DT_SUBTABLE *Subtable,
691 void *Context,
692 void *ReturnValue)
693 {
694 UINT8 Checksum;
695 UINT8 *Sum = ReturnValue;
696
697
698 Checksum = AcpiUtChecksum (Subtable->Buffer, Subtable->Length);
699 *Sum = (UINT8) (*Sum + Checksum);
700 }
701
702
703 /******************************************************************************
704 *
705 * FUNCTION: DtSetTableChecksum
706 *
707 * PARAMETERS: ChecksumPointer - Where to return the checksum
708 *
709 * RETURN: None
710 *
711 * DESCRIPTION: Set checksum of the whole data table into the checksum field
712 *
713 *****************************************************************************/
714
715 void
716 DtSetTableChecksum (
717 UINT8 *ChecksumPointer)
718 {
719 UINT8 Checksum = 0;
720 UINT8 OldSum;
721
722
723 DtWalkTableTree (AslGbl_RootTable, DtSum, NULL, &Checksum);
724
725 OldSum = *ChecksumPointer;
726 Checksum = (UINT8) (Checksum - OldSum);
727
728 /* Compute the final checksum */
729
730 Checksum = (UINT8) (0 - Checksum);
731 *ChecksumPointer = Checksum;
732 }
733
734
735 /******************************************************************************
736 *
737 * FUNCTION: DtSetTableLength
738 *
739 * PARAMETERS: None
740 *
741 * RETURN: None
742 *
743 * DESCRIPTION: Walk the subtables and set all the length fields
744 *
745 *****************************************************************************/
746
747 void
748 DtSetTableLength (
749 void)
750 {
751 DT_SUBTABLE *ParentTable;
752 DT_SUBTABLE *ChildTable;
753
754
755 ParentTable = AslGbl_RootTable;
756 ChildTable = NULL;
757
758 if (!ParentTable)
759 {
760 return;
761 }
762
763 DtSetSubtableLength (ParentTable);
764
765 while (1)
766 {
767 ChildTable = DtGetNextSubtable (ParentTable, ChildTable);
768 if (ChildTable)
769 {
770 if (ChildTable->LengthField)
771 {
772 DtSetSubtableLength (ChildTable);
773 }
774
775 if (ChildTable->Child)
776 {
777 ParentTable = ChildTable;
778 ChildTable = NULL;
779 }
780 else
781 {
782 ParentTable->TotalLength += ChildTable->TotalLength;
783 if (ParentTable->LengthField)
784 {
785 DtSetSubtableLength (ParentTable);
786 }
787 }
788 }
789 else
790 {
791 ChildTable = ParentTable;
792
793 if (ChildTable == AslGbl_RootTable)
794 {
795 break;
796 }
797
798 ParentTable = DtGetParentSubtable (ParentTable);
799
800 ParentTable->TotalLength += ChildTable->TotalLength;
801 if (ParentTable->LengthField)
802 {
803 DtSetSubtableLength (ParentTable);
804 }
805 }
806 }
807 }
808
809
810 /******************************************************************************
811 *
812 * FUNCTION: DtWalkTableTree
813 *
814 * PARAMETERS: StartTable - Subtable in the tree where walking begins
815 * UserFunction - Called during the walk
816 * Context - Passed to user function
817 * ReturnValue - The return value of UserFunction
818 *
819 * RETURN: None
820 *
821 * DESCRIPTION: Performs a depth-first walk of the subtable tree
822 *
823 *****************************************************************************/
824
825 void
826 DtWalkTableTree (
827 DT_SUBTABLE *StartTable,
828 DT_WALK_CALLBACK UserFunction,
829 void *Context,
830 void *ReturnValue)
831 {
832 DT_SUBTABLE *ParentTable;
833 DT_SUBTABLE *ChildTable;
834
835
836 ParentTable = StartTable;
837 ChildTable = NULL;
838
839 if (!ParentTable)
840 {
841 return;
842 }
843
844 UserFunction (ParentTable, Context, ReturnValue);
845
846 while (1)
847 {
848 ChildTable = DtGetNextSubtable (ParentTable, ChildTable);
849 if (ChildTable)
850 {
851 UserFunction (ChildTable, Context, ReturnValue);
852
853 if (ChildTable->Child)
854 {
855 ParentTable = ChildTable;
856 ChildTable = NULL;
857 }
858 }
859 else
860 {
861 ChildTable = ParentTable;
862 if (ChildTable == AslGbl_RootTable)
863 {
864 break;
865 }
866
867 ParentTable = DtGetParentSubtable (ParentTable);
868
869 if (ChildTable->Peer == StartTable)
870 {
871 break;
872 }
873 }
874 }
875 }
876