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rscalc.c revision 1.1
      1 /*******************************************************************************
      2  *
      3  * Module Name: rscalc - Calculate stream and list lengths
      4  *
      5  ******************************************************************************/
      6 
      7 /******************************************************************************
      8  *
      9  * 1. Copyright Notice
     10  *
     11  * Some or all of this work - Copyright (c) 1999 - 2010, Intel Corp.
     12  * All rights reserved.
     13  *
     14  * 2. License
     15  *
     16  * 2.1. This is your license from Intel Corp. under its intellectual property
     17  * rights.  You may have additional license terms from the party that provided
     18  * you this software, covering your right to use that party's intellectual
     19  * property rights.
     20  *
     21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
     22  * copy of the source code appearing in this file ("Covered Code") an
     23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
     24  * base code distributed originally by Intel ("Original Intel Code") to copy,
     25  * make derivatives, distribute, use and display any portion of the Covered
     26  * Code in any form, with the right to sublicense such rights; and
     27  *
     28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
     29  * license (with the right to sublicense), under only those claims of Intel
     30  * patents that are infringed by the Original Intel Code, to make, use, sell,
     31  * offer to sell, and import the Covered Code and derivative works thereof
     32  * solely to the minimum extent necessary to exercise the above copyright
     33  * license, and in no event shall the patent license extend to any additions
     34  * to or modifications of the Original Intel Code.  No other license or right
     35  * is granted directly or by implication, estoppel or otherwise;
     36  *
     37  * The above copyright and patent license is granted only if the following
     38  * conditions are met:
     39  *
     40  * 3. Conditions
     41  *
     42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
     43  * Redistribution of source code of any substantial portion of the Covered
     44  * Code or modification with rights to further distribute source must include
     45  * the above Copyright Notice, the above License, this list of Conditions,
     46  * and the following Disclaimer and Export Compliance provision.  In addition,
     47  * Licensee must cause all Covered Code to which Licensee contributes to
     48  * contain a file documenting the changes Licensee made to create that Covered
     49  * Code and the date of any change.  Licensee must include in that file the
     50  * documentation of any changes made by any predecessor Licensee.  Licensee
     51  * must include a prominent statement that the modification is derived,
     52  * directly or indirectly, from Original Intel Code.
     53  *
     54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
     55  * Redistribution of source code of any substantial portion of the Covered
     56  * Code or modification without rights to further distribute source must
     57  * include the following Disclaimer and Export Compliance provision in the
     58  * documentation and/or other materials provided with distribution.  In
     59  * addition, Licensee may not authorize further sublicense of source of any
     60  * portion of the Covered Code, and must include terms to the effect that the
     61  * license from Licensee to its licensee is limited to the intellectual
     62  * property embodied in the software Licensee provides to its licensee, and
     63  * not to intellectual property embodied in modifications its licensee may
     64  * make.
     65  *
     66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
     67  * substantial portion of the Covered Code or modification must reproduce the
     68  * above Copyright Notice, and the following Disclaimer and Export Compliance
     69  * provision in the documentation and/or other materials provided with the
     70  * distribution.
     71  *
     72  * 3.4. Intel retains all right, title, and interest in and to the Original
     73  * Intel Code.
     74  *
     75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
     76  * Intel shall be used in advertising or otherwise to promote the sale, use or
     77  * other dealings in products derived from or relating to the Covered Code
     78  * without prior written authorization from Intel.
     79  *
     80  * 4. Disclaimer and Export Compliance
     81  *
     82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
     83  * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
     84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
     85  * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
     86  * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
     87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
     88  * PARTICULAR PURPOSE.
     89  *
     90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
     91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
     92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
     93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
     94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
     95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
     96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
     97  * LIMITED REMEDY.
     98  *
     99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
    100  * software or system incorporating such software without first obtaining any
    101  * required license or other approval from the U. S. Department of Commerce or
    102  * any other agency or department of the United States Government.  In the
    103  * event Licensee exports any such software from the United States or
    104  * re-exports any such software from a foreign destination, Licensee shall
    105  * ensure that the distribution and export/re-export of the software is in
    106  * compliance with all laws, regulations, orders, or other restrictions of the
    107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
    108  * any of its subsidiaries will export/re-export any technical data, process,
    109  * software, or service, directly or indirectly, to any country for which the
    110  * United States government or any agency thereof requires an export license,
    111  * other governmental approval, or letter of assurance, without first obtaining
    112  * such license, approval or letter.
    113  *
    114  *****************************************************************************/
    115 
    116 #define __RSCALC_C__
    117 
    118 #include "acpi.h"
    119 #include "accommon.h"
    120 #include "acresrc.h"
    121 #include "acnamesp.h"
    122 
    123 
    124 #define _COMPONENT          ACPI_RESOURCES
    125         ACPI_MODULE_NAME    ("rscalc")
    126 
    127 
    128 /* Local prototypes */
    129 
    130 static UINT8
    131 AcpiRsCountSetBits (
    132     UINT16                  BitField);
    133 
    134 static ACPI_RS_LENGTH
    135 AcpiRsStructOptionLength (
    136     ACPI_RESOURCE_SOURCE    *ResourceSource);
    137 
    138 static UINT32
    139 AcpiRsStreamOptionLength (
    140     UINT32                  ResourceLength,
    141     UINT32                  MinimumTotalLength);
    142 
    143 
    144 /*******************************************************************************
    145  *
    146  * FUNCTION:    AcpiRsCountSetBits
    147  *
    148  * PARAMETERS:  BitField        - Field in which to count bits
    149  *
    150  * RETURN:      Number of bits set within the field
    151  *
    152  * DESCRIPTION: Count the number of bits set in a resource field. Used for
    153  *              (Short descriptor) interrupt and DMA lists.
    154  *
    155  ******************************************************************************/
    156 
    157 static UINT8
    158 AcpiRsCountSetBits (
    159     UINT16                  BitField)
    160 {
    161     UINT8                   BitsSet;
    162 
    163 
    164     ACPI_FUNCTION_ENTRY ();
    165 
    166 
    167     for (BitsSet = 0; BitField; BitsSet++)
    168     {
    169         /* Zero the least significant bit that is set */
    170 
    171         BitField &= (UINT16) (BitField - 1);
    172     }
    173 
    174     return (BitsSet);
    175 }
    176 
    177 
    178 /*******************************************************************************
    179  *
    180  * FUNCTION:    AcpiRsStructOptionLength
    181  *
    182  * PARAMETERS:  ResourceSource      - Pointer to optional descriptor field
    183  *
    184  * RETURN:      Status
    185  *
    186  * DESCRIPTION: Common code to handle optional ResourceSourceIndex and
    187  *              ResourceSource fields in some Large descriptors. Used during
    188  *              list-to-stream conversion
    189  *
    190  ******************************************************************************/
    191 
    192 static ACPI_RS_LENGTH
    193 AcpiRsStructOptionLength (
    194     ACPI_RESOURCE_SOURCE    *ResourceSource)
    195 {
    196     ACPI_FUNCTION_ENTRY ();
    197 
    198 
    199     /*
    200      * If the ResourceSource string is valid, return the size of the string
    201      * (StringLength includes the NULL terminator) plus the size of the
    202      * ResourceSourceIndex (1).
    203      */
    204     if (ResourceSource->StringPtr)
    205     {
    206         return ((ACPI_RS_LENGTH) (ResourceSource->StringLength + 1));
    207     }
    208 
    209     return (0);
    210 }
    211 
    212 
    213 /*******************************************************************************
    214  *
    215  * FUNCTION:    AcpiRsStreamOptionLength
    216  *
    217  * PARAMETERS:  ResourceLength      - Length from the resource header
    218  *              MinimumTotalLength  - Minimum length of this resource, before
    219  *                                    any optional fields. Includes header size
    220  *
    221  * RETURN:      Length of optional string (0 if no string present)
    222  *
    223  * DESCRIPTION: Common code to handle optional ResourceSourceIndex and
    224  *              ResourceSource fields in some Large descriptors. Used during
    225  *              stream-to-list conversion
    226  *
    227  ******************************************************************************/
    228 
    229 static UINT32
    230 AcpiRsStreamOptionLength (
    231     UINT32                  ResourceLength,
    232     UINT32                  MinimumAmlResourceLength)
    233 {
    234     UINT32                  StringLength = 0;
    235 
    236 
    237     ACPI_FUNCTION_ENTRY ();
    238 
    239 
    240     /*
    241      * The ResourceSourceIndex and ResourceSource are optional elements of some
    242      * Large-type resource descriptors.
    243      */
    244 
    245     /*
    246      * If the length of the actual resource descriptor is greater than the ACPI
    247      * spec-defined minimum length, it means that a ResourceSourceIndex exists
    248      * and is followed by a (required) null terminated string. The string length
    249      * (including the null terminator) is the resource length minus the minimum
    250      * length, minus one byte for the ResourceSourceIndex itself.
    251      */
    252     if (ResourceLength > MinimumAmlResourceLength)
    253     {
    254         /* Compute the length of the optional string */
    255 
    256         StringLength = ResourceLength - MinimumAmlResourceLength - 1;
    257     }
    258 
    259     /*
    260      * Round the length up to a multiple of the native word in order to
    261      * guarantee that the entire resource descriptor is native word aligned
    262      */
    263     return ((UINT32) ACPI_ROUND_UP_TO_NATIVE_WORD (StringLength));
    264 }
    265 
    266 
    267 /*******************************************************************************
    268  *
    269  * FUNCTION:    AcpiRsGetAmlLength
    270  *
    271  * PARAMETERS:  Resource            - Pointer to the resource linked list
    272  *              SizeNeeded          - Where the required size is returned
    273  *
    274  * RETURN:      Status
    275  *
    276  * DESCRIPTION: Takes a linked list of internal resource descriptors and
    277  *              calculates the size buffer needed to hold the corresponding
    278  *              external resource byte stream.
    279  *
    280  ******************************************************************************/
    281 
    282 ACPI_STATUS
    283 AcpiRsGetAmlLength (
    284     ACPI_RESOURCE           *Resource,
    285     ACPI_SIZE               *SizeNeeded)
    286 {
    287     ACPI_SIZE               AmlSizeNeeded = 0;
    288     ACPI_RS_LENGTH          TotalSize;
    289 
    290 
    291     ACPI_FUNCTION_TRACE (RsGetAmlLength);
    292 
    293 
    294     /* Traverse entire list of internal resource descriptors */
    295 
    296     while (Resource)
    297     {
    298         /* Validate the descriptor type */
    299 
    300         if (Resource->Type > ACPI_RESOURCE_TYPE_MAX)
    301         {
    302             return_ACPI_STATUS (AE_AML_INVALID_RESOURCE_TYPE);
    303         }
    304 
    305         /* Get the base size of the (external stream) resource descriptor */
    306 
    307         TotalSize = AcpiGbl_AmlResourceSizes [Resource->Type];
    308 
    309         /*
    310          * Augment the base size for descriptors with optional and/or
    311          * variable-length fields
    312          */
    313         switch (Resource->Type)
    314         {
    315         case ACPI_RESOURCE_TYPE_IRQ:
    316 
    317             /* Length can be 3 or 2 */
    318 
    319             if (Resource->Data.Irq.DescriptorLength == 2)
    320             {
    321                 TotalSize--;
    322             }
    323             break;
    324 
    325 
    326         case ACPI_RESOURCE_TYPE_START_DEPENDENT:
    327 
    328             /* Length can be 1 or 0 */
    329 
    330             if (Resource->Data.Irq.DescriptorLength == 0)
    331             {
    332                 TotalSize--;
    333             }
    334             break;
    335 
    336 
    337         case ACPI_RESOURCE_TYPE_VENDOR:
    338             /*
    339              * Vendor Defined Resource:
    340              * For a Vendor Specific resource, if the Length is between 1 and 7
    341              * it will be created as a Small Resource data type, otherwise it
    342              * is a Large Resource data type.
    343              */
    344             if (Resource->Data.Vendor.ByteLength > 7)
    345             {
    346                 /* Base size of a Large resource descriptor */
    347 
    348                 TotalSize = sizeof (AML_RESOURCE_LARGE_HEADER);
    349             }
    350 
    351             /* Add the size of the vendor-specific data */
    352 
    353             TotalSize = (ACPI_RS_LENGTH)
    354                 (TotalSize + Resource->Data.Vendor.ByteLength);
    355             break;
    356 
    357 
    358         case ACPI_RESOURCE_TYPE_END_TAG:
    359             /*
    360              * End Tag:
    361              * We are done -- return the accumulated total size.
    362              */
    363             *SizeNeeded = AmlSizeNeeded + TotalSize;
    364 
    365             /* Normal exit */
    366 
    367             return_ACPI_STATUS (AE_OK);
    368 
    369 
    370         case ACPI_RESOURCE_TYPE_ADDRESS16:
    371             /*
    372              * 16-Bit Address Resource:
    373              * Add the size of the optional ResourceSource info
    374              */
    375             TotalSize = (ACPI_RS_LENGTH)
    376                 (TotalSize + AcpiRsStructOptionLength (
    377                                 &Resource->Data.Address16.ResourceSource));
    378             break;
    379 
    380 
    381         case ACPI_RESOURCE_TYPE_ADDRESS32:
    382             /*
    383              * 32-Bit Address Resource:
    384              * Add the size of the optional ResourceSource info
    385              */
    386             TotalSize = (ACPI_RS_LENGTH)
    387                 (TotalSize + AcpiRsStructOptionLength (
    388                                 &Resource->Data.Address32.ResourceSource));
    389             break;
    390 
    391 
    392         case ACPI_RESOURCE_TYPE_ADDRESS64:
    393             /*
    394              * 64-Bit Address Resource:
    395              * Add the size of the optional ResourceSource info
    396              */
    397             TotalSize = (ACPI_RS_LENGTH)
    398                 (TotalSize + AcpiRsStructOptionLength (
    399                                 &Resource->Data.Address64.ResourceSource));
    400             break;
    401 
    402 
    403         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
    404             /*
    405              * Extended IRQ Resource:
    406              * Add the size of each additional optional interrupt beyond the
    407              * required 1 (4 bytes for each UINT32 interrupt number)
    408              */
    409             TotalSize = (ACPI_RS_LENGTH)
    410                 (TotalSize +
    411                 ((Resource->Data.ExtendedIrq.InterruptCount - 1) * 4) +
    412 
    413                 /* Add the size of the optional ResourceSource info */
    414 
    415                 AcpiRsStructOptionLength (
    416                     &Resource->Data.ExtendedIrq.ResourceSource));
    417             break;
    418 
    419 
    420         default:
    421             break;
    422         }
    423 
    424         /* Update the total */
    425 
    426         AmlSizeNeeded += TotalSize;
    427 
    428         /* Point to the next object */
    429 
    430         Resource = ACPI_ADD_PTR (ACPI_RESOURCE, Resource, Resource->Length);
    431     }
    432 
    433     /* Did not find an EndTag resource descriptor */
    434 
    435     return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
    436 }
    437 
    438 
    439 /*******************************************************************************
    440  *
    441  * FUNCTION:    AcpiRsGetListLength
    442  *
    443  * PARAMETERS:  AmlBuffer           - Pointer to the resource byte stream
    444  *              AmlBufferLength     - Size of AmlBuffer
    445  *              SizeNeeded          - Where the size needed is returned
    446  *
    447  * RETURN:      Status
    448  *
    449  * DESCRIPTION: Takes an external resource byte stream and calculates the size
    450  *              buffer needed to hold the corresponding internal resource
    451  *              descriptor linked list.
    452  *
    453  ******************************************************************************/
    454 
    455 ACPI_STATUS
    456 AcpiRsGetListLength (
    457     UINT8                   *AmlBuffer,
    458     UINT32                  AmlBufferLength,
    459     ACPI_SIZE               *SizeNeeded)
    460 {
    461     ACPI_STATUS             Status;
    462     UINT8                   *EndAml;
    463     UINT8                   *Buffer;
    464     UINT32                  BufferSize;
    465     UINT16                  Temp16;
    466     UINT16                  ResourceLength;
    467     UINT32                  ExtraStructBytes;
    468     UINT8                   ResourceIndex;
    469     UINT8                   MinimumAmlResourceLength;
    470 
    471 
    472     ACPI_FUNCTION_TRACE (RsGetListLength);
    473 
    474 
    475     *SizeNeeded = 0;
    476     EndAml = AmlBuffer + AmlBufferLength;
    477 
    478     /* Walk the list of AML resource descriptors */
    479 
    480     while (AmlBuffer < EndAml)
    481     {
    482         /* Validate the Resource Type and Resource Length */
    483 
    484         Status = AcpiUtValidateResource (AmlBuffer, &ResourceIndex);
    485         if (ACPI_FAILURE (Status))
    486         {
    487             return_ACPI_STATUS (Status);
    488         }
    489 
    490         /* Get the resource length and base (minimum) AML size */
    491 
    492         ResourceLength = AcpiUtGetResourceLength (AmlBuffer);
    493         MinimumAmlResourceLength = AcpiGbl_ResourceAmlSizes[ResourceIndex];
    494 
    495         /*
    496          * Augment the size for descriptors with optional
    497          * and/or variable length fields
    498          */
    499         ExtraStructBytes = 0;
    500         Buffer = AmlBuffer + AcpiUtGetResourceHeaderLength (AmlBuffer);
    501 
    502         switch (AcpiUtGetResourceType (AmlBuffer))
    503         {
    504         case ACPI_RESOURCE_NAME_IRQ:
    505             /*
    506              * IRQ Resource:
    507              * Get the number of bits set in the 16-bit IRQ mask
    508              */
    509             ACPI_MOVE_16_TO_16 (&Temp16, Buffer);
    510             ExtraStructBytes = AcpiRsCountSetBits (Temp16);
    511             break;
    512 
    513 
    514         case ACPI_RESOURCE_NAME_DMA:
    515             /*
    516              * DMA Resource:
    517              * Get the number of bits set in the 8-bit DMA mask
    518              */
    519             ExtraStructBytes = AcpiRsCountSetBits (*Buffer);
    520             break;
    521 
    522 
    523         case ACPI_RESOURCE_NAME_VENDOR_SMALL:
    524         case ACPI_RESOURCE_NAME_VENDOR_LARGE:
    525             /*
    526              * Vendor Resource:
    527              * Get the number of vendor data bytes
    528              */
    529             ExtraStructBytes = ResourceLength;
    530             break;
    531 
    532 
    533         case ACPI_RESOURCE_NAME_END_TAG:
    534             /*
    535              * End Tag:
    536              * This is the normal exit, add size of EndTag
    537              */
    538             *SizeNeeded += ACPI_RS_SIZE_MIN;
    539             return_ACPI_STATUS (AE_OK);
    540 
    541 
    542         case ACPI_RESOURCE_NAME_ADDRESS32:
    543         case ACPI_RESOURCE_NAME_ADDRESS16:
    544         case ACPI_RESOURCE_NAME_ADDRESS64:
    545             /*
    546              * Address Resource:
    547              * Add the size of the optional ResourceSource
    548              */
    549             ExtraStructBytes = AcpiRsStreamOptionLength (
    550                 ResourceLength, MinimumAmlResourceLength);
    551             break;
    552 
    553 
    554         case ACPI_RESOURCE_NAME_EXTENDED_IRQ:
    555             /*
    556              * Extended IRQ Resource:
    557              * Using the InterruptTableLength, add 4 bytes for each additional
    558              * interrupt. Note: at least one interrupt is required and is
    559              * included in the minimum descriptor size (reason for the -1)
    560              */
    561             ExtraStructBytes = (Buffer[1] - 1) * sizeof (UINT32);
    562 
    563             /* Add the size of the optional ResourceSource */
    564 
    565             ExtraStructBytes += AcpiRsStreamOptionLength (
    566                 ResourceLength - ExtraStructBytes, MinimumAmlResourceLength);
    567             break;
    568 
    569 
    570         default:
    571             break;
    572         }
    573 
    574         /*
    575          * Update the required buffer size for the internal descriptor structs
    576          *
    577          * Important: Round the size up for the appropriate alignment. This
    578          * is a requirement on IA64.
    579          */
    580         BufferSize = AcpiGbl_ResourceStructSizes[ResourceIndex] +
    581                         ExtraStructBytes;
    582         BufferSize = (UINT32) ACPI_ROUND_UP_TO_NATIVE_WORD (BufferSize);
    583 
    584         *SizeNeeded += BufferSize;
    585 
    586         ACPI_DEBUG_PRINT ((ACPI_DB_RESOURCES,
    587             "Type %.2X, AmlLength %.2X InternalLength %.2X\n",
    588             AcpiUtGetResourceType (AmlBuffer),
    589             AcpiUtGetDescriptorLength (AmlBuffer), BufferSize));
    590 
    591         /*
    592          * Point to the next resource within the AML stream using the length
    593          * contained in the resource descriptor header
    594          */
    595         AmlBuffer += AcpiUtGetDescriptorLength (AmlBuffer);
    596     }
    597 
    598     /* Did not find an EndTag resource descriptor */
    599 
    600     return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
    601 }
    602 
    603 
    604 /*******************************************************************************
    605  *
    606  * FUNCTION:    AcpiRsGetPciRoutingTableLength
    607  *
    608  * PARAMETERS:  PackageObject           - Pointer to the package object
    609  *              BufferSizeNeeded        - UINT32 pointer of the size buffer
    610  *                                        needed to properly return the
    611  *                                        parsed data
    612  *
    613  * RETURN:      Status
    614  *
    615  * DESCRIPTION: Given a package representing a PCI routing table, this
    616  *              calculates the size of the corresponding linked list of
    617  *              descriptions.
    618  *
    619  ******************************************************************************/
    620 
    621 ACPI_STATUS
    622 AcpiRsGetPciRoutingTableLength (
    623     ACPI_OPERAND_OBJECT     *PackageObject,
    624     ACPI_SIZE               *BufferSizeNeeded)
    625 {
    626     UINT32                  NumberOfElements;
    627     ACPI_SIZE               TempSizeNeeded = 0;
    628     ACPI_OPERAND_OBJECT     **TopObjectList;
    629     UINT32                  Index;
    630     ACPI_OPERAND_OBJECT     *PackageElement;
    631     ACPI_OPERAND_OBJECT     **SubObjectList;
    632     BOOLEAN                 NameFound;
    633     UINT32                  TableIndex;
    634 
    635 
    636     ACPI_FUNCTION_TRACE (RsGetPciRoutingTableLength);
    637 
    638 
    639     NumberOfElements = PackageObject->Package.Count;
    640 
    641     /*
    642      * Calculate the size of the return buffer.
    643      * The base size is the number of elements * the sizes of the
    644      * structures.  Additional space for the strings is added below.
    645      * The minus one is to subtract the size of the UINT8 Source[1]
    646      * member because it is added below.
    647      *
    648      * But each PRT_ENTRY structure has a pointer to a string and
    649      * the size of that string must be found.
    650      */
    651     TopObjectList = PackageObject->Package.Elements;
    652 
    653     for (Index = 0; Index < NumberOfElements; Index++)
    654     {
    655         /* Dereference the sub-package */
    656 
    657         PackageElement = *TopObjectList;
    658 
    659         /* We must have a valid Package object */
    660 
    661         if (!PackageElement ||
    662             (PackageElement->Common.Type != ACPI_TYPE_PACKAGE))
    663         {
    664             return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
    665         }
    666 
    667         /*
    668          * The SubObjectList will now point to an array of the
    669          * four IRQ elements: Address, Pin, Source and SourceIndex
    670          */
    671         SubObjectList = PackageElement->Package.Elements;
    672 
    673         /* Scan the IrqTableElements for the Source Name String */
    674 
    675         NameFound = FALSE;
    676 
    677         for (TableIndex = 0; TableIndex < 4 && !NameFound; TableIndex++)
    678         {
    679             if (*SubObjectList && /* Null object allowed */
    680 
    681                 ((ACPI_TYPE_STRING ==
    682                     (*SubObjectList)->Common.Type) ||
    683 
    684                 ((ACPI_TYPE_LOCAL_REFERENCE ==
    685                     (*SubObjectList)->Common.Type) &&
    686 
    687                     ((*SubObjectList)->Reference.Class ==
    688                         ACPI_REFCLASS_NAME))))
    689             {
    690                 NameFound = TRUE;
    691             }
    692             else
    693             {
    694                 /* Look at the next element */
    695 
    696                 SubObjectList++;
    697             }
    698         }
    699 
    700         TempSizeNeeded += (sizeof (ACPI_PCI_ROUTING_TABLE) - 4);
    701 
    702         /* Was a String type found? */
    703 
    704         if (NameFound)
    705         {
    706             if ((*SubObjectList)->Common.Type == ACPI_TYPE_STRING)
    707             {
    708                 /*
    709                  * The length String.Length field does not include the
    710                  * terminating NULL, add 1
    711                  */
    712                 TempSizeNeeded += ((ACPI_SIZE)
    713                     (*SubObjectList)->String.Length + 1);
    714             }
    715             else
    716             {
    717                 TempSizeNeeded += AcpiNsGetPathnameLength (
    718                                     (*SubObjectList)->Reference.Node);
    719             }
    720         }
    721         else
    722         {
    723             /*
    724              * If no name was found, then this is a NULL, which is
    725              * translated as a UINT32 zero.
    726              */
    727             TempSizeNeeded += sizeof (UINT32);
    728         }
    729 
    730         /* Round up the size since each element must be aligned */
    731 
    732         TempSizeNeeded = ACPI_ROUND_UP_TO_64BIT (TempSizeNeeded);
    733 
    734         /* Point to the next ACPI_OPERAND_OBJECT */
    735 
    736         TopObjectList++;
    737     }
    738 
    739     /*
    740      * Add an extra element to the end of the list, essentially a
    741      * NULL terminator
    742      */
    743     *BufferSizeNeeded = TempSizeNeeded + sizeof (ACPI_PCI_ROUTING_TABLE);
    744     return_ACPI_STATUS (AE_OK);
    745 }
    746