xref: /freebsd/sys/contrib/dev/acpica/components/resources/rscalc.c (revision 94e3ee44c3581ff37c5e01b5ffe5eb16d30079a7)
1 /*******************************************************************************
2  *
3  * Module Name: rscalc - Calculate stream and list lengths
4  *
5  ******************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2012, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #define __RSCALC_C__
45 
46 #include <contrib/dev/acpica/include/acpi.h>
47 #include <contrib/dev/acpica/include/accommon.h>
48 #include <contrib/dev/acpica/include/acresrc.h>
49 #include <contrib/dev/acpica/include/acnamesp.h>
50 
51 
52 #define _COMPONENT          ACPI_RESOURCES
53         ACPI_MODULE_NAME    ("rscalc")
54 
55 
56 /* Local prototypes */
57 
58 static UINT8
59 AcpiRsCountSetBits (
60     UINT16                  BitField);
61 
62 static ACPI_RS_LENGTH
63 AcpiRsStructOptionLength (
64     ACPI_RESOURCE_SOURCE    *ResourceSource);
65 
66 static UINT32
67 AcpiRsStreamOptionLength (
68     UINT32                  ResourceLength,
69     UINT32                  MinimumTotalLength);
70 
71 
72 /*******************************************************************************
73  *
74  * FUNCTION:    AcpiRsCountSetBits
75  *
76  * PARAMETERS:  BitField        - Field in which to count bits
77  *
78  * RETURN:      Number of bits set within the field
79  *
80  * DESCRIPTION: Count the number of bits set in a resource field. Used for
81  *              (Short descriptor) interrupt and DMA lists.
82  *
83  ******************************************************************************/
84 
85 static UINT8
86 AcpiRsCountSetBits (
87     UINT16                  BitField)
88 {
89     UINT8                   BitsSet;
90 
91 
92     ACPI_FUNCTION_ENTRY ();
93 
94 
95     for (BitsSet = 0; BitField; BitsSet++)
96     {
97         /* Zero the least significant bit that is set */
98 
99         BitField &= (UINT16) (BitField - 1);
100     }
101 
102     return (BitsSet);
103 }
104 
105 
106 /*******************************************************************************
107  *
108  * FUNCTION:    AcpiRsStructOptionLength
109  *
110  * PARAMETERS:  ResourceSource      - Pointer to optional descriptor field
111  *
112  * RETURN:      Status
113  *
114  * DESCRIPTION: Common code to handle optional ResourceSourceIndex and
115  *              ResourceSource fields in some Large descriptors. Used during
116  *              list-to-stream conversion
117  *
118  ******************************************************************************/
119 
120 static ACPI_RS_LENGTH
121 AcpiRsStructOptionLength (
122     ACPI_RESOURCE_SOURCE    *ResourceSource)
123 {
124     ACPI_FUNCTION_ENTRY ();
125 
126 
127     /*
128      * If the ResourceSource string is valid, return the size of the string
129      * (StringLength includes the NULL terminator) plus the size of the
130      * ResourceSourceIndex (1).
131      */
132     if (ResourceSource->StringPtr)
133     {
134         return ((ACPI_RS_LENGTH) (ResourceSource->StringLength + 1));
135     }
136 
137     return (0);
138 }
139 
140 
141 /*******************************************************************************
142  *
143  * FUNCTION:    AcpiRsStreamOptionLength
144  *
145  * PARAMETERS:  ResourceLength      - Length from the resource header
146  *              MinimumTotalLength  - Minimum length of this resource, before
147  *                                    any optional fields. Includes header size
148  *
149  * RETURN:      Length of optional string (0 if no string present)
150  *
151  * DESCRIPTION: Common code to handle optional ResourceSourceIndex and
152  *              ResourceSource fields in some Large descriptors. Used during
153  *              stream-to-list conversion
154  *
155  ******************************************************************************/
156 
157 static UINT32
158 AcpiRsStreamOptionLength (
159     UINT32                  ResourceLength,
160     UINT32                  MinimumAmlResourceLength)
161 {
162     UINT32                  StringLength = 0;
163 
164 
165     ACPI_FUNCTION_ENTRY ();
166 
167 
168     /*
169      * The ResourceSourceIndex and ResourceSource are optional elements of some
170      * Large-type resource descriptors.
171      */
172 
173     /*
174      * If the length of the actual resource descriptor is greater than the ACPI
175      * spec-defined minimum length, it means that a ResourceSourceIndex exists
176      * and is followed by a (required) null terminated string. The string length
177      * (including the null terminator) is the resource length minus the minimum
178      * length, minus one byte for the ResourceSourceIndex itself.
179      */
180     if (ResourceLength > MinimumAmlResourceLength)
181     {
182         /* Compute the length of the optional string */
183 
184         StringLength = ResourceLength - MinimumAmlResourceLength - 1;
185     }
186 
187     /*
188      * Round the length up to a multiple of the native word in order to
189      * guarantee that the entire resource descriptor is native word aligned
190      */
191     return ((UINT32) ACPI_ROUND_UP_TO_NATIVE_WORD (StringLength));
192 }
193 
194 
195 /*******************************************************************************
196  *
197  * FUNCTION:    AcpiRsGetAmlLength
198  *
199  * PARAMETERS:  Resource            - Pointer to the resource linked list
200  *              SizeNeeded          - Where the required size is returned
201  *
202  * RETURN:      Status
203  *
204  * DESCRIPTION: Takes a linked list of internal resource descriptors and
205  *              calculates the size buffer needed to hold the corresponding
206  *              external resource byte stream.
207  *
208  ******************************************************************************/
209 
210 ACPI_STATUS
211 AcpiRsGetAmlLength (
212     ACPI_RESOURCE           *Resource,
213     ACPI_SIZE               *SizeNeeded)
214 {
215     ACPI_SIZE               AmlSizeNeeded = 0;
216     ACPI_RS_LENGTH          TotalSize;
217 
218 
219     ACPI_FUNCTION_TRACE (RsGetAmlLength);
220 
221 
222     /* Traverse entire list of internal resource descriptors */
223 
224     while (Resource)
225     {
226         /* Validate the descriptor type */
227 
228         if (Resource->Type > ACPI_RESOURCE_TYPE_MAX)
229         {
230             return_ACPI_STATUS (AE_AML_INVALID_RESOURCE_TYPE);
231         }
232 
233         /* Get the base size of the (external stream) resource descriptor */
234 
235         TotalSize = AcpiGbl_AmlResourceSizes [Resource->Type];
236 
237         /*
238          * Augment the base size for descriptors with optional and/or
239          * variable-length fields
240          */
241         switch (Resource->Type)
242         {
243         case ACPI_RESOURCE_TYPE_IRQ:
244 
245             /* Length can be 3 or 2 */
246 
247             if (Resource->Data.Irq.DescriptorLength == 2)
248             {
249                 TotalSize--;
250             }
251             break;
252 
253 
254         case ACPI_RESOURCE_TYPE_START_DEPENDENT:
255 
256             /* Length can be 1 or 0 */
257 
258             if (Resource->Data.Irq.DescriptorLength == 0)
259             {
260                 TotalSize--;
261             }
262             break;
263 
264 
265         case ACPI_RESOURCE_TYPE_VENDOR:
266             /*
267              * Vendor Defined Resource:
268              * For a Vendor Specific resource, if the Length is between 1 and 7
269              * it will be created as a Small Resource data type, otherwise it
270              * is a Large Resource data type.
271              */
272             if (Resource->Data.Vendor.ByteLength > 7)
273             {
274                 /* Base size of a Large resource descriptor */
275 
276                 TotalSize = sizeof (AML_RESOURCE_LARGE_HEADER);
277             }
278 
279             /* Add the size of the vendor-specific data */
280 
281             TotalSize = (ACPI_RS_LENGTH)
282                 (TotalSize + Resource->Data.Vendor.ByteLength);
283             break;
284 
285 
286         case ACPI_RESOURCE_TYPE_END_TAG:
287             /*
288              * End Tag:
289              * We are done -- return the accumulated total size.
290              */
291             *SizeNeeded = AmlSizeNeeded + TotalSize;
292 
293             /* Normal exit */
294 
295             return_ACPI_STATUS (AE_OK);
296 
297 
298         case ACPI_RESOURCE_TYPE_ADDRESS16:
299             /*
300              * 16-Bit Address Resource:
301              * Add the size of the optional ResourceSource info
302              */
303             TotalSize = (ACPI_RS_LENGTH)
304                 (TotalSize + AcpiRsStructOptionLength (
305                                 &Resource->Data.Address16.ResourceSource));
306             break;
307 
308 
309         case ACPI_RESOURCE_TYPE_ADDRESS32:
310             /*
311              * 32-Bit Address Resource:
312              * Add the size of the optional ResourceSource info
313              */
314             TotalSize = (ACPI_RS_LENGTH)
315                 (TotalSize + AcpiRsStructOptionLength (
316                                 &Resource->Data.Address32.ResourceSource));
317             break;
318 
319 
320         case ACPI_RESOURCE_TYPE_ADDRESS64:
321             /*
322              * 64-Bit Address Resource:
323              * Add the size of the optional ResourceSource info
324              */
325             TotalSize = (ACPI_RS_LENGTH)
326                 (TotalSize + AcpiRsStructOptionLength (
327                                 &Resource->Data.Address64.ResourceSource));
328             break;
329 
330 
331         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
332             /*
333              * Extended IRQ Resource:
334              * Add the size of each additional optional interrupt beyond the
335              * required 1 (4 bytes for each UINT32 interrupt number)
336              */
337             TotalSize = (ACPI_RS_LENGTH)
338                 (TotalSize +
339                 ((Resource->Data.ExtendedIrq.InterruptCount - 1) * 4) +
340 
341                 /* Add the size of the optional ResourceSource info */
342 
343                 AcpiRsStructOptionLength (
344                     &Resource->Data.ExtendedIrq.ResourceSource));
345             break;
346 
347 
348         case ACPI_RESOURCE_TYPE_GPIO:
349 
350             TotalSize = (ACPI_RS_LENGTH) (TotalSize + (Resource->Data.Gpio.PinTableLength * 2) +
351                 Resource->Data.Gpio.ResourceSource.StringLength +
352                 Resource->Data.Gpio.VendorLength);
353 
354             break;
355 
356 
357         case ACPI_RESOURCE_TYPE_SERIAL_BUS:
358 
359             TotalSize = AcpiGbl_AmlResourceSerialBusSizes [Resource->Data.CommonSerialBus.Type];
360 
361             TotalSize = (ACPI_RS_LENGTH) (TotalSize +
362                 Resource->Data.I2cSerialBus.ResourceSource.StringLength +
363                 Resource->Data.I2cSerialBus.VendorLength);
364 
365             break;
366 
367 
368         default:
369             break;
370         }
371 
372         /* Update the total */
373 
374         AmlSizeNeeded += TotalSize;
375 
376         /* Point to the next object */
377 
378         Resource = ACPI_ADD_PTR (ACPI_RESOURCE, Resource, Resource->Length);
379     }
380 
381     /* Did not find an EndTag resource descriptor */
382 
383     return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
384 }
385 
386 
387 /*******************************************************************************
388  *
389  * FUNCTION:    AcpiRsGetListLength
390  *
391  * PARAMETERS:  AmlBuffer           - Pointer to the resource byte stream
392  *              AmlBufferLength     - Size of AmlBuffer
393  *              SizeNeeded          - Where the size needed is returned
394  *
395  * RETURN:      Status
396  *
397  * DESCRIPTION: Takes an external resource byte stream and calculates the size
398  *              buffer needed to hold the corresponding internal resource
399  *              descriptor linked list.
400  *
401  ******************************************************************************/
402 
403 ACPI_STATUS
404 AcpiRsGetListLength (
405     UINT8                   *AmlBuffer,
406     UINT32                  AmlBufferLength,
407     ACPI_SIZE               *SizeNeeded)
408 {
409     ACPI_STATUS             Status;
410     UINT8                   *EndAml;
411     UINT8                   *Buffer;
412     UINT32                  BufferSize;
413     UINT16                  Temp16;
414     UINT16                  ResourceLength;
415     UINT32                  ExtraStructBytes;
416     UINT8                   ResourceIndex;
417     UINT8                   MinimumAmlResourceLength;
418     AML_RESOURCE            *AmlResource;
419 
420 
421     ACPI_FUNCTION_TRACE (RsGetListLength);
422 
423 
424     *SizeNeeded = ACPI_RS_SIZE_MIN;         /* Minimum size is one EndTag */
425     EndAml = AmlBuffer + AmlBufferLength;
426 
427     /* Walk the list of AML resource descriptors */
428 
429     while (AmlBuffer < EndAml)
430     {
431         /* Validate the Resource Type and Resource Length */
432 
433         Status = AcpiUtValidateResource (AmlBuffer, &ResourceIndex);
434         if (ACPI_FAILURE (Status))
435         {
436             /*
437              * Exit on failure. Cannot continue because the descriptor length
438              * may be bogus also.
439              */
440             return_ACPI_STATUS (Status);
441         }
442 
443         AmlResource = (void *) AmlBuffer;
444 
445         /* Get the resource length and base (minimum) AML size */
446 
447         ResourceLength = AcpiUtGetResourceLength (AmlBuffer);
448         MinimumAmlResourceLength = AcpiGbl_ResourceAmlSizes[ResourceIndex];
449 
450         /*
451          * Augment the size for descriptors with optional
452          * and/or variable length fields
453          */
454         ExtraStructBytes = 0;
455         Buffer = AmlBuffer + AcpiUtGetResourceHeaderLength (AmlBuffer);
456 
457         switch (AcpiUtGetResourceType (AmlBuffer))
458         {
459         case ACPI_RESOURCE_NAME_IRQ:
460             /*
461              * IRQ Resource:
462              * Get the number of bits set in the 16-bit IRQ mask
463              */
464             ACPI_MOVE_16_TO_16 (&Temp16, Buffer);
465             ExtraStructBytes = AcpiRsCountSetBits (Temp16);
466             break;
467 
468 
469         case ACPI_RESOURCE_NAME_DMA:
470             /*
471              * DMA Resource:
472              * Get the number of bits set in the 8-bit DMA mask
473              */
474             ExtraStructBytes = AcpiRsCountSetBits (*Buffer);
475             break;
476 
477 
478         case ACPI_RESOURCE_NAME_VENDOR_SMALL:
479         case ACPI_RESOURCE_NAME_VENDOR_LARGE:
480             /*
481              * Vendor Resource:
482              * Get the number of vendor data bytes
483              */
484             ExtraStructBytes = ResourceLength;
485             break;
486 
487 
488         case ACPI_RESOURCE_NAME_END_TAG:
489             /*
490              * End Tag: This is the normal exit
491              */
492             return_ACPI_STATUS (AE_OK);
493 
494 
495         case ACPI_RESOURCE_NAME_ADDRESS32:
496         case ACPI_RESOURCE_NAME_ADDRESS16:
497         case ACPI_RESOURCE_NAME_ADDRESS64:
498             /*
499              * Address Resource:
500              * Add the size of the optional ResourceSource
501              */
502             ExtraStructBytes = AcpiRsStreamOptionLength (
503                 ResourceLength, MinimumAmlResourceLength);
504             break;
505 
506 
507         case ACPI_RESOURCE_NAME_EXTENDED_IRQ:
508             /*
509              * Extended IRQ Resource:
510              * Using the InterruptTableLength, add 4 bytes for each additional
511              * interrupt. Note: at least one interrupt is required and is
512              * included in the minimum descriptor size (reason for the -1)
513              */
514             ExtraStructBytes = (Buffer[1] - 1) * sizeof (UINT32);
515 
516             /* Add the size of the optional ResourceSource */
517 
518             ExtraStructBytes += AcpiRsStreamOptionLength (
519                 ResourceLength - ExtraStructBytes, MinimumAmlResourceLength);
520             break;
521 
522         case ACPI_RESOURCE_NAME_GPIO:
523 
524             /* Vendor data is optional */
525 
526             if (AmlResource->Gpio.VendorLength)
527             {
528                 ExtraStructBytes += AmlResource->Gpio.VendorOffset -
529                     AmlResource->Gpio.PinTableOffset + AmlResource->Gpio.VendorLength;
530             }
531             else
532             {
533                 ExtraStructBytes += AmlResource->LargeHeader.ResourceLength +
534                     sizeof (AML_RESOURCE_LARGE_HEADER) -
535                     AmlResource->Gpio.PinTableOffset;
536             }
537             break;
538 
539         case ACPI_RESOURCE_NAME_SERIAL_BUS:
540 
541             MinimumAmlResourceLength = AcpiGbl_ResourceAmlSerialBusSizes[
542                 AmlResource->CommonSerialBus.Type];
543             ExtraStructBytes += AmlResource->CommonSerialBus.ResourceLength -
544                 MinimumAmlResourceLength;
545             break;
546 
547         default:
548             break;
549         }
550 
551         /*
552          * Update the required buffer size for the internal descriptor structs
553          *
554          * Important: Round the size up for the appropriate alignment. This
555          * is a requirement on IA64.
556          */
557         if (AcpiUtGetResourceType (AmlBuffer) == ACPI_RESOURCE_NAME_SERIAL_BUS)
558         {
559             BufferSize = AcpiGbl_ResourceStructSerialBusSizes[
560                 AmlResource->CommonSerialBus.Type] + ExtraStructBytes;
561         }
562         else
563         {
564             BufferSize = AcpiGbl_ResourceStructSizes[ResourceIndex] +
565                         ExtraStructBytes;
566         }
567         BufferSize = (UINT32) ACPI_ROUND_UP_TO_NATIVE_WORD (BufferSize);
568 
569         *SizeNeeded += BufferSize;
570 
571         ACPI_DEBUG_PRINT ((ACPI_DB_RESOURCES,
572             "Type %.2X, AmlLength %.2X InternalLength %.2X\n",
573             AcpiUtGetResourceType (AmlBuffer),
574             AcpiUtGetDescriptorLength (AmlBuffer), BufferSize));
575 
576         /*
577          * Point to the next resource within the AML stream using the length
578          * contained in the resource descriptor header
579          */
580         AmlBuffer += AcpiUtGetDescriptorLength (AmlBuffer);
581     }
582 
583     /* Did not find an EndTag resource descriptor */
584 
585     return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
586 }
587 
588 
589 /*******************************************************************************
590  *
591  * FUNCTION:    AcpiRsGetPciRoutingTableLength
592  *
593  * PARAMETERS:  PackageObject           - Pointer to the package object
594  *              BufferSizeNeeded        - UINT32 pointer of the size buffer
595  *                                        needed to properly return the
596  *                                        parsed data
597  *
598  * RETURN:      Status
599  *
600  * DESCRIPTION: Given a package representing a PCI routing table, this
601  *              calculates the size of the corresponding linked list of
602  *              descriptions.
603  *
604  ******************************************************************************/
605 
606 ACPI_STATUS
607 AcpiRsGetPciRoutingTableLength (
608     ACPI_OPERAND_OBJECT     *PackageObject,
609     ACPI_SIZE               *BufferSizeNeeded)
610 {
611     UINT32                  NumberOfElements;
612     ACPI_SIZE               TempSizeNeeded = 0;
613     ACPI_OPERAND_OBJECT     **TopObjectList;
614     UINT32                  Index;
615     ACPI_OPERAND_OBJECT     *PackageElement;
616     ACPI_OPERAND_OBJECT     **SubObjectList;
617     BOOLEAN                 NameFound;
618     UINT32                  TableIndex;
619 
620 
621     ACPI_FUNCTION_TRACE (RsGetPciRoutingTableLength);
622 
623 
624     NumberOfElements = PackageObject->Package.Count;
625 
626     /*
627      * Calculate the size of the return buffer.
628      * The base size is the number of elements * the sizes of the
629      * structures.  Additional space for the strings is added below.
630      * The minus one is to subtract the size of the UINT8 Source[1]
631      * member because it is added below.
632      *
633      * But each PRT_ENTRY structure has a pointer to a string and
634      * the size of that string must be found.
635      */
636     TopObjectList = PackageObject->Package.Elements;
637 
638     for (Index = 0; Index < NumberOfElements; Index++)
639     {
640         /* Dereference the sub-package */
641 
642         PackageElement = *TopObjectList;
643 
644         /* We must have a valid Package object */
645 
646         if (!PackageElement ||
647             (PackageElement->Common.Type != ACPI_TYPE_PACKAGE))
648         {
649             return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
650         }
651 
652         /*
653          * The SubObjectList will now point to an array of the
654          * four IRQ elements: Address, Pin, Source and SourceIndex
655          */
656         SubObjectList = PackageElement->Package.Elements;
657 
658         /* Scan the IrqTableElements for the Source Name String */
659 
660         NameFound = FALSE;
661 
662         for (TableIndex = 0; TableIndex < 4 && !NameFound; TableIndex++)
663         {
664             if (*SubObjectList && /* Null object allowed */
665 
666                 ((ACPI_TYPE_STRING ==
667                     (*SubObjectList)->Common.Type) ||
668 
669                 ((ACPI_TYPE_LOCAL_REFERENCE ==
670                     (*SubObjectList)->Common.Type) &&
671 
672                     ((*SubObjectList)->Reference.Class ==
673                         ACPI_REFCLASS_NAME))))
674             {
675                 NameFound = TRUE;
676             }
677             else
678             {
679                 /* Look at the next element */
680 
681                 SubObjectList++;
682             }
683         }
684 
685         TempSizeNeeded += (sizeof (ACPI_PCI_ROUTING_TABLE) - 4);
686 
687         /* Was a String type found? */
688 
689         if (NameFound)
690         {
691             if ((*SubObjectList)->Common.Type == ACPI_TYPE_STRING)
692             {
693                 /*
694                  * The length String.Length field does not include the
695                  * terminating NULL, add 1
696                  */
697                 TempSizeNeeded += ((ACPI_SIZE)
698                     (*SubObjectList)->String.Length + 1);
699             }
700             else
701             {
702                 TempSizeNeeded += AcpiNsGetPathnameLength (
703                                     (*SubObjectList)->Reference.Node);
704             }
705         }
706         else
707         {
708             /*
709              * If no name was found, then this is a NULL, which is
710              * translated as a UINT32 zero.
711              */
712             TempSizeNeeded += sizeof (UINT32);
713         }
714 
715         /* Round up the size since each element must be aligned */
716 
717         TempSizeNeeded = ACPI_ROUND_UP_TO_64BIT (TempSizeNeeded);
718 
719         /* Point to the next ACPI_OPERAND_OBJECT */
720 
721         TopObjectList++;
722     }
723 
724     /*
725      * Add an extra element to the end of the list, essentially a
726      * NULL terminator
727      */
728     *BufferSizeNeeded = TempSizeNeeded + sizeof (ACPI_PCI_ROUTING_TABLE);
729     return_ACPI_STATUS (AE_OK);
730 }
731