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rscalc.c revision 1.1.1.4
      1 /*******************************************************************************
      2  *
      3  * Module Name: rscalc - Calculate stream and list lengths
      4  *
      5  ******************************************************************************/
      6 
      7 /*
      8  * Copyright (C) 2000 - 2014, 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 "acpi.h"
     47 #include "accommon.h"
     48 #include "acresrc.h"
     49 #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  *              ResourceListSize    - Size of the resource linked list
    201  *              SizeNeeded          - Where the required size is returned
    202  *
    203  * RETURN:      Status
    204  *
    205  * DESCRIPTION: Takes a linked list of internal resource descriptors and
    206  *              calculates the size buffer needed to hold the corresponding
    207  *              external resource byte stream.
    208  *
    209  ******************************************************************************/
    210 
    211 ACPI_STATUS
    212 AcpiRsGetAmlLength (
    213     ACPI_RESOURCE           *Resource,
    214     ACPI_SIZE               ResourceListSize,
    215     ACPI_SIZE               *SizeNeeded)
    216 {
    217     ACPI_SIZE               AmlSizeNeeded = 0;
    218     ACPI_RESOURCE           *ResourceEnd;
    219     ACPI_RS_LENGTH          TotalSize;
    220 
    221 
    222     ACPI_FUNCTION_TRACE (RsGetAmlLength);
    223 
    224 
    225     /* Traverse entire list of internal resource descriptors */
    226 
    227     ResourceEnd = ACPI_ADD_PTR (ACPI_RESOURCE, Resource, ResourceListSize);
    228     while (Resource < ResourceEnd)
    229     {
    230         /* Validate the descriptor type */
    231 
    232         if (Resource->Type > ACPI_RESOURCE_TYPE_MAX)
    233         {
    234             return_ACPI_STATUS (AE_AML_INVALID_RESOURCE_TYPE);
    235         }
    236 
    237         /* Sanity check the length. It must not be zero, or we loop forever */
    238 
    239         if (!Resource->Length)
    240         {
    241             return_ACPI_STATUS (AE_AML_BAD_RESOURCE_LENGTH);
    242         }
    243 
    244         /* Get the base size of the (external stream) resource descriptor */
    245 
    246         TotalSize = AcpiGbl_AmlResourceSizes [Resource->Type];
    247 
    248         /*
    249          * Augment the base size for descriptors with optional and/or
    250          * variable-length fields
    251          */
    252         switch (Resource->Type)
    253         {
    254         case ACPI_RESOURCE_TYPE_IRQ:
    255 
    256             /* Length can be 3 or 2 */
    257 
    258             if (Resource->Data.Irq.DescriptorLength == 2)
    259             {
    260                 TotalSize--;
    261             }
    262             break;
    263 
    264 
    265         case ACPI_RESOURCE_TYPE_START_DEPENDENT:
    266 
    267             /* Length can be 1 or 0 */
    268 
    269             if (Resource->Data.Irq.DescriptorLength == 0)
    270             {
    271                 TotalSize--;
    272             }
    273             break;
    274 
    275 
    276         case ACPI_RESOURCE_TYPE_VENDOR:
    277             /*
    278              * Vendor Defined Resource:
    279              * For a Vendor Specific resource, if the Length is between 1 and 7
    280              * it will be created as a Small Resource data type, otherwise it
    281              * is a Large Resource data type.
    282              */
    283             if (Resource->Data.Vendor.ByteLength > 7)
    284             {
    285                 /* Base size of a Large resource descriptor */
    286 
    287                 TotalSize = sizeof (AML_RESOURCE_LARGE_HEADER);
    288             }
    289 
    290             /* Add the size of the vendor-specific data */
    291 
    292             TotalSize = (ACPI_RS_LENGTH)
    293                 (TotalSize + Resource->Data.Vendor.ByteLength);
    294             break;
    295 
    296 
    297         case ACPI_RESOURCE_TYPE_END_TAG:
    298             /*
    299              * End Tag:
    300              * We are done -- return the accumulated total size.
    301              */
    302             *SizeNeeded = AmlSizeNeeded + TotalSize;
    303 
    304             /* Normal exit */
    305 
    306             return_ACPI_STATUS (AE_OK);
    307 
    308 
    309         case ACPI_RESOURCE_TYPE_ADDRESS16:
    310             /*
    311              * 16-Bit Address Resource:
    312              * Add the size of the optional ResourceSource info
    313              */
    314             TotalSize = (ACPI_RS_LENGTH)
    315                 (TotalSize + AcpiRsStructOptionLength (
    316                                 &Resource->Data.Address16.ResourceSource));
    317             break;
    318 
    319 
    320         case ACPI_RESOURCE_TYPE_ADDRESS32:
    321             /*
    322              * 32-Bit Address Resource:
    323              * Add the size of the optional ResourceSource info
    324              */
    325             TotalSize = (ACPI_RS_LENGTH)
    326                 (TotalSize + AcpiRsStructOptionLength (
    327                                 &Resource->Data.Address32.ResourceSource));
    328             break;
    329 
    330 
    331         case ACPI_RESOURCE_TYPE_ADDRESS64:
    332             /*
    333              * 64-Bit Address Resource:
    334              * Add the size of the optional ResourceSource info
    335              */
    336             TotalSize = (ACPI_RS_LENGTH)
    337                 (TotalSize + AcpiRsStructOptionLength (
    338                                 &Resource->Data.Address64.ResourceSource));
    339             break;
    340 
    341 
    342         case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
    343             /*
    344              * Extended IRQ Resource:
    345              * Add the size of each additional optional interrupt beyond the
    346              * required 1 (4 bytes for each UINT32 interrupt number)
    347              */
    348             TotalSize = (ACPI_RS_LENGTH)
    349                 (TotalSize +
    350                 ((Resource->Data.ExtendedIrq.InterruptCount - 1) * 4) +
    351 
    352                 /* Add the size of the optional ResourceSource info */
    353 
    354                 AcpiRsStructOptionLength (
    355                     &Resource->Data.ExtendedIrq.ResourceSource));
    356             break;
    357 
    358 
    359         case ACPI_RESOURCE_TYPE_GPIO:
    360 
    361             TotalSize = (ACPI_RS_LENGTH) (TotalSize + (Resource->Data.Gpio.PinTableLength * 2) +
    362                 Resource->Data.Gpio.ResourceSource.StringLength +
    363                 Resource->Data.Gpio.VendorLength);
    364 
    365             break;
    366 
    367 
    368         case ACPI_RESOURCE_TYPE_SERIAL_BUS:
    369 
    370             TotalSize = AcpiGbl_AmlResourceSerialBusSizes [Resource->Data.CommonSerialBus.Type];
    371 
    372             TotalSize = (ACPI_RS_LENGTH) (TotalSize +
    373                 Resource->Data.I2cSerialBus.ResourceSource.StringLength +
    374                 Resource->Data.I2cSerialBus.VendorLength);
    375 
    376             break;
    377 
    378         default:
    379 
    380             break;
    381         }
    382 
    383         /* Update the total */
    384 
    385         AmlSizeNeeded += TotalSize;
    386 
    387         /* Point to the next object */
    388 
    389         Resource = ACPI_ADD_PTR (ACPI_RESOURCE, Resource, Resource->Length);
    390     }
    391 
    392     /* Did not find an EndTag resource descriptor */
    393 
    394     return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
    395 }
    396 
    397 
    398 /*******************************************************************************
    399  *
    400  * FUNCTION:    AcpiRsGetListLength
    401  *
    402  * PARAMETERS:  AmlBuffer           - Pointer to the resource byte stream
    403  *              AmlBufferLength     - Size of AmlBuffer
    404  *              SizeNeeded          - Where the size needed is returned
    405  *
    406  * RETURN:      Status
    407  *
    408  * DESCRIPTION: Takes an external resource byte stream and calculates the size
    409  *              buffer needed to hold the corresponding internal resource
    410  *              descriptor linked list.
    411  *
    412  ******************************************************************************/
    413 
    414 ACPI_STATUS
    415 AcpiRsGetListLength (
    416     UINT8                   *AmlBuffer,
    417     UINT32                  AmlBufferLength,
    418     ACPI_SIZE               *SizeNeeded)
    419 {
    420     ACPI_STATUS             Status;
    421     UINT8                   *EndAml;
    422     UINT8                   *Buffer;
    423     UINT32                  BufferSize;
    424     UINT16                  Temp16;
    425     UINT16                  ResourceLength;
    426     UINT32                  ExtraStructBytes;
    427     UINT8                   ResourceIndex;
    428     UINT8                   MinimumAmlResourceLength;
    429     AML_RESOURCE            *AmlResource;
    430 
    431 
    432     ACPI_FUNCTION_TRACE (RsGetListLength);
    433 
    434 
    435     *SizeNeeded = ACPI_RS_SIZE_MIN;         /* Minimum size is one EndTag */
    436     EndAml = AmlBuffer + AmlBufferLength;
    437 
    438     /* Walk the list of AML resource descriptors */
    439 
    440     while (AmlBuffer < EndAml)
    441     {
    442         /* Validate the Resource Type and Resource Length */
    443 
    444         Status = AcpiUtValidateResource (NULL, AmlBuffer, &ResourceIndex);
    445         if (ACPI_FAILURE (Status))
    446         {
    447             /*
    448              * Exit on failure. Cannot continue because the descriptor length
    449              * may be bogus also.
    450              */
    451             return_ACPI_STATUS (Status);
    452         }
    453 
    454         AmlResource = (void *) AmlBuffer;
    455 
    456         /* Get the resource length and base (minimum) AML size */
    457 
    458         ResourceLength = AcpiUtGetResourceLength (AmlBuffer);
    459         MinimumAmlResourceLength = AcpiGbl_ResourceAmlSizes[ResourceIndex];
    460 
    461         /*
    462          * Augment the size for descriptors with optional
    463          * and/or variable length fields
    464          */
    465         ExtraStructBytes = 0;
    466         Buffer = AmlBuffer + AcpiUtGetResourceHeaderLength (AmlBuffer);
    467 
    468         switch (AcpiUtGetResourceType (AmlBuffer))
    469         {
    470         case ACPI_RESOURCE_NAME_IRQ:
    471             /*
    472              * IRQ Resource:
    473              * Get the number of bits set in the 16-bit IRQ mask
    474              */
    475             ACPI_MOVE_16_TO_16 (&Temp16, Buffer);
    476             ExtraStructBytes = AcpiRsCountSetBits (Temp16);
    477             break;
    478 
    479 
    480         case ACPI_RESOURCE_NAME_DMA:
    481             /*
    482              * DMA Resource:
    483              * Get the number of bits set in the 8-bit DMA mask
    484              */
    485             ExtraStructBytes = AcpiRsCountSetBits (*Buffer);
    486             break;
    487 
    488 
    489         case ACPI_RESOURCE_NAME_VENDOR_SMALL:
    490         case ACPI_RESOURCE_NAME_VENDOR_LARGE:
    491             /*
    492              * Vendor Resource:
    493              * Get the number of vendor data bytes
    494              */
    495             ExtraStructBytes = ResourceLength;
    496 
    497             /*
    498              * There is already one byte included in the minimum
    499              * descriptor size. If there are extra struct bytes,
    500              * subtract one from the count.
    501              */
    502             if (ExtraStructBytes)
    503             {
    504                 ExtraStructBytes--;
    505             }
    506             break;
    507 
    508 
    509         case ACPI_RESOURCE_NAME_END_TAG:
    510             /*
    511              * End Tag: This is the normal exit
    512              */
    513             return_ACPI_STATUS (AE_OK);
    514 
    515 
    516         case ACPI_RESOURCE_NAME_ADDRESS32:
    517         case ACPI_RESOURCE_NAME_ADDRESS16:
    518         case ACPI_RESOURCE_NAME_ADDRESS64:
    519             /*
    520              * Address Resource:
    521              * Add the size of the optional ResourceSource
    522              */
    523             ExtraStructBytes = AcpiRsStreamOptionLength (
    524                 ResourceLength, MinimumAmlResourceLength);
    525             break;
    526 
    527 
    528         case ACPI_RESOURCE_NAME_EXTENDED_IRQ:
    529             /*
    530              * Extended IRQ Resource:
    531              * Using the InterruptTableLength, add 4 bytes for each additional
    532              * interrupt. Note: at least one interrupt is required and is
    533              * included in the minimum descriptor size (reason for the -1)
    534              */
    535             ExtraStructBytes = (Buffer[1] - 1) * sizeof (UINT32);
    536 
    537             /* Add the size of the optional ResourceSource */
    538 
    539             ExtraStructBytes += AcpiRsStreamOptionLength (
    540                 ResourceLength - ExtraStructBytes, MinimumAmlResourceLength);
    541             break;
    542 
    543         case ACPI_RESOURCE_NAME_GPIO:
    544 
    545             /* Vendor data is optional */
    546 
    547             if (AmlResource->Gpio.VendorLength)
    548             {
    549                 ExtraStructBytes += AmlResource->Gpio.VendorOffset -
    550                     AmlResource->Gpio.PinTableOffset + AmlResource->Gpio.VendorLength;
    551             }
    552             else
    553             {
    554                 ExtraStructBytes += AmlResource->LargeHeader.ResourceLength +
    555                     sizeof (AML_RESOURCE_LARGE_HEADER) -
    556                     AmlResource->Gpio.PinTableOffset;
    557             }
    558             break;
    559 
    560         case ACPI_RESOURCE_NAME_SERIAL_BUS:
    561 
    562             MinimumAmlResourceLength = AcpiGbl_ResourceAmlSerialBusSizes[
    563                 AmlResource->CommonSerialBus.Type];
    564             ExtraStructBytes += AmlResource->CommonSerialBus.ResourceLength -
    565                 MinimumAmlResourceLength;
    566             break;
    567 
    568         default:
    569 
    570             break;
    571         }
    572 
    573         /*
    574          * Update the required buffer size for the internal descriptor structs
    575          *
    576          * Important: Round the size up for the appropriate alignment. This
    577          * is a requirement on IA64.
    578          */
    579         if (AcpiUtGetResourceType (AmlBuffer) == ACPI_RESOURCE_NAME_SERIAL_BUS)
    580         {
    581             BufferSize = AcpiGbl_ResourceStructSerialBusSizes[
    582                 AmlResource->CommonSerialBus.Type] + ExtraStructBytes;
    583         }
    584         else
    585         {
    586             BufferSize = AcpiGbl_ResourceStructSizes[ResourceIndex] +
    587                         ExtraStructBytes;
    588         }
    589         BufferSize = (UINT32) ACPI_ROUND_UP_TO_NATIVE_WORD (BufferSize);
    590 
    591         *SizeNeeded += BufferSize;
    592 
    593         ACPI_DEBUG_PRINT ((ACPI_DB_RESOURCES,
    594             "Type %.2X, AmlLength %.2X InternalLength %.2X\n",
    595             AcpiUtGetResourceType (AmlBuffer),
    596             AcpiUtGetDescriptorLength (AmlBuffer), BufferSize));
    597 
    598         /*
    599          * Point to the next resource within the AML stream using the length
    600          * contained in the resource descriptor header
    601          */
    602         AmlBuffer += AcpiUtGetDescriptorLength (AmlBuffer);
    603     }
    604 
    605     /* Did not find an EndTag resource descriptor */
    606 
    607     return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
    608 }
    609 
    610 
    611 /*******************************************************************************
    612  *
    613  * FUNCTION:    AcpiRsGetPciRoutingTableLength
    614  *
    615  * PARAMETERS:  PackageObject           - Pointer to the package object
    616  *              BufferSizeNeeded        - UINT32 pointer of the size buffer
    617  *                                        needed to properly return the
    618  *                                        parsed data
    619  *
    620  * RETURN:      Status
    621  *
    622  * DESCRIPTION: Given a package representing a PCI routing table, this
    623  *              calculates the size of the corresponding linked list of
    624  *              descriptions.
    625  *
    626  ******************************************************************************/
    627 
    628 ACPI_STATUS
    629 AcpiRsGetPciRoutingTableLength (
    630     ACPI_OPERAND_OBJECT     *PackageObject,
    631     ACPI_SIZE               *BufferSizeNeeded)
    632 {
    633     UINT32                  NumberOfElements;
    634     ACPI_SIZE               TempSizeNeeded = 0;
    635     ACPI_OPERAND_OBJECT     **TopObjectList;
    636     UINT32                  Index;
    637     ACPI_OPERAND_OBJECT     *PackageElement;
    638     ACPI_OPERAND_OBJECT     **SubObjectList;
    639     BOOLEAN                 NameFound;
    640     UINT32                  TableIndex;
    641 
    642 
    643     ACPI_FUNCTION_TRACE (RsGetPciRoutingTableLength);
    644 
    645 
    646     NumberOfElements = PackageObject->Package.Count;
    647 
    648     /*
    649      * Calculate the size of the return buffer.
    650      * The base size is the number of elements * the sizes of the
    651      * structures. Additional space for the strings is added below.
    652      * The minus one is to subtract the size of the UINT8 Source[1]
    653      * member because it is added below.
    654      *
    655      * But each PRT_ENTRY structure has a pointer to a string and
    656      * the size of that string must be found.
    657      */
    658     TopObjectList = PackageObject->Package.Elements;
    659 
    660     for (Index = 0; Index < NumberOfElements; Index++)
    661     {
    662         /* Dereference the subpackage */
    663 
    664         PackageElement = *TopObjectList;
    665 
    666         /* We must have a valid Package object */
    667 
    668         if (!PackageElement ||
    669             (PackageElement->Common.Type != ACPI_TYPE_PACKAGE))
    670         {
    671             return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
    672         }
    673 
    674         /*
    675          * The SubObjectList will now point to an array of the
    676          * four IRQ elements: Address, Pin, Source and SourceIndex
    677          */
    678         SubObjectList = PackageElement->Package.Elements;
    679 
    680         /* Scan the IrqTableElements for the Source Name String */
    681 
    682         NameFound = FALSE;
    683 
    684         for (TableIndex = 0;
    685              TableIndex < PackageElement->Package.Count && !NameFound;
    686              TableIndex++)
    687         {
    688             if (*SubObjectList && /* Null object allowed */
    689 
    690                 ((ACPI_TYPE_STRING ==
    691                     (*SubObjectList)->Common.Type) ||
    692 
    693                 ((ACPI_TYPE_LOCAL_REFERENCE ==
    694                     (*SubObjectList)->Common.Type) &&
    695 
    696                     ((*SubObjectList)->Reference.Class ==
    697                         ACPI_REFCLASS_NAME))))
    698             {
    699                 NameFound = TRUE;
    700             }
    701             else
    702             {
    703                 /* Look at the next element */
    704 
    705                 SubObjectList++;
    706             }
    707         }
    708 
    709         TempSizeNeeded += (sizeof (ACPI_PCI_ROUTING_TABLE) - 4);
    710 
    711         /* Was a String type found? */
    712 
    713         if (NameFound)
    714         {
    715             if ((*SubObjectList)->Common.Type == ACPI_TYPE_STRING)
    716             {
    717                 /*
    718                  * The length String.Length field does not include the
    719                  * terminating NULL, add 1
    720                  */
    721                 TempSizeNeeded += ((ACPI_SIZE)
    722                     (*SubObjectList)->String.Length + 1);
    723             }
    724             else
    725             {
    726                 TempSizeNeeded += AcpiNsGetPathnameLength (
    727                                     (*SubObjectList)->Reference.Node);
    728             }
    729         }
    730         else
    731         {
    732             /*
    733              * If no name was found, then this is a NULL, which is
    734              * translated as a UINT32 zero.
    735              */
    736             TempSizeNeeded += sizeof (UINT32);
    737         }
    738 
    739         /* Round up the size since each element must be aligned */
    740 
    741         TempSizeNeeded = ACPI_ROUND_UP_TO_64BIT (TempSizeNeeded);
    742 
    743         /* Point to the next ACPI_OPERAND_OBJECT */
    744 
    745         TopObjectList++;
    746     }
    747 
    748     /*
    749      * Add an extra element to the end of the list, essentially a
    750      * NULL terminator
    751      */
    752     *BufferSizeNeeded = TempSizeNeeded + sizeof (ACPI_PCI_ROUTING_TABLE);
    753     return_ACPI_STATUS (AE_OK);
    754 }
    755