LXR linux/drivers/acpi/acpica/rscalc.c

   1/*******************************************************************************
   2 *
   3 * Module Name: rscalc - Calculate stream and list lengths
   4 *
   5 ******************************************************************************/
   6
   7/*
   8 * Copyright (C) 2000 - 2016, 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#include <acpi/acpi.h>
  45#include "accommon.h"
  46#include "acresrc.h"
  47#include "acnamesp.h"
  48
  49#define _COMPONENT          ACPI_RESOURCES
  50ACPI_MODULE_NAME("rscalc")
  51
  52/* Local prototypes */
  53static u8 acpi_rs_count_set_bits(u16 bit_field);
  54
  55static acpi_rs_length
  56acpi_rs_struct_option_length(struct acpi_resource_source *resource_source);
  57
  58static u32
  59acpi_rs_stream_option_length(u32 resource_length, u32 minimum_total_length);
  60
  61/*******************************************************************************
  62 *
  63 * FUNCTION:    acpi_rs_count_set_bits
  64 *
  65 * PARAMETERS:  bit_field       - Field in which to count bits
  66 *
  67 * RETURN:      Number of bits set within the field
  68 *
  69 * DESCRIPTION: Count the number of bits set in a resource field. Used for
  70 *              (Short descriptor) interrupt and DMA lists.
  71 *
  72 ******************************************************************************/
  73
  74static u8 acpi_rs_count_set_bits(u16 bit_field)
  75{
  76        u8 bits_set;
  77
  78        ACPI_FUNCTION_ENTRY();
  79
  80        for (bits_set = 0; bit_field; bits_set++) {
  81
  82                /* Zero the least significant bit that is set */
  83
  84                bit_field &= (u16) (bit_field - 1);
  85        }
  86
  87        return (bits_set);
  88}
  89
  90/*******************************************************************************
  91 *
  92 * FUNCTION:    acpi_rs_struct_option_length
  93 *
  94 * PARAMETERS:  resource_source     - Pointer to optional descriptor field
  95 *
  96 * RETURN:      Status
  97 *
  98 * DESCRIPTION: Common code to handle optional resource_source_index and
  99 *              resource_source fields in some Large descriptors. Used during
 100 *              list-to-stream conversion
 101 *
 102 ******************************************************************************/
 103
 104static acpi_rs_length
 105acpi_rs_struct_option_length(struct acpi_resource_source *resource_source)
 106{
 107        ACPI_FUNCTION_ENTRY();
 108
 109        /*
 110         * If the resource_source string is valid, return the size of the string
 111         * (string_length includes the NULL terminator) plus the size of the
 112         * resource_source_index (1).
 113         */
 114        if (resource_source->string_ptr) {
 115                return ((acpi_rs_length) (resource_source->string_length + 1));
 116        }
 117
 118        return (0);
 119}
 120
 121/*******************************************************************************
 122 *
 123 * FUNCTION:    acpi_rs_stream_option_length
 124 *
 125 * PARAMETERS:  resource_length     - Length from the resource header
 126 *              minimum_total_length - Minimum length of this resource, before
 127 *                                    any optional fields. Includes header size
 128 *
 129 * RETURN:      Length of optional string (0 if no string present)
 130 *
 131 * DESCRIPTION: Common code to handle optional resource_source_index and
 132 *              resource_source fields in some Large descriptors. Used during
 133 *              stream-to-list conversion
 134 *
 135 ******************************************************************************/
 136
 137static u32
 138acpi_rs_stream_option_length(u32 resource_length,
 139                             u32 minimum_aml_resource_length)
 140{
 141        u32 string_length = 0;
 142
 143        ACPI_FUNCTION_ENTRY();
 144
 145        /*
 146         * The resource_source_index and resource_source are optional elements of
 147         * some Large-type resource descriptors.
 148         */
 149
 150        /*
 151         * If the length of the actual resource descriptor is greater than the
 152         * ACPI spec-defined minimum length, it means that a resource_source_index
 153         * exists and is followed by a (required) null terminated string. The
 154         * string length (including the null terminator) is the resource length
 155         * minus the minimum length, minus one byte for the resource_source_index
 156         * itself.
 157         */
 158        if (resource_length > minimum_aml_resource_length) {
 159
 160                /* Compute the length of the optional string */
 161
 162                string_length =
 163                    resource_length - minimum_aml_resource_length - 1;
 164        }
 165
 166        /*
 167         * Round the length up to a multiple of the native word in order to
 168         * guarantee that the entire resource descriptor is native word aligned
 169         */
 170        return ((u32) ACPI_ROUND_UP_TO_NATIVE_WORD(string_length));
 171}
 172
 173/*******************************************************************************
 174 *
 175 * FUNCTION:    acpi_rs_get_aml_length
 176 *
 177 * PARAMETERS:  resource            - Pointer to the resource linked list
 178 *              resource_list_size  - Size of the resource linked list
 179 *              size_needed         - Where the required size is returned
 180 *
 181 * RETURN:      Status
 182 *
 183 * DESCRIPTION: Takes a linked list of internal resource descriptors and
 184 *              calculates the size buffer needed to hold the corresponding
 185 *              external resource byte stream.
 186 *
 187 ******************************************************************************/
 188
 189acpi_status
 190acpi_rs_get_aml_length(struct acpi_resource *resource,
 191                       acpi_size resource_list_size, acpi_size * size_needed)
 192{
 193        acpi_size aml_size_needed = 0;
 194        struct acpi_resource *resource_end;
 195        acpi_rs_length total_size;
 196
 197        ACPI_FUNCTION_TRACE(rs_get_aml_length);
 198
 199        /* Traverse entire list of internal resource descriptors */
 200
 201        resource_end =
 202            ACPI_ADD_PTR(struct acpi_resource, resource, resource_list_size);
 203        while (resource < resource_end) {
 204
 205                /* Validate the descriptor type */
 206
 207                if (resource->type > ACPI_RESOURCE_TYPE_MAX) {
 208                        return_ACPI_STATUS(AE_AML_INVALID_RESOURCE_TYPE);
 209                }
 210
 211                /* Sanity check the length. It must not be zero, or we loop forever */
 212
 213                if (!resource->length) {
 214                        return_ACPI_STATUS(AE_AML_BAD_RESOURCE_LENGTH);
 215                }
 216
 217                /* Get the base size of the (external stream) resource descriptor */
 218
 219                total_size = acpi_gbl_aml_resource_sizes[resource->type];
 220
 221                /*
 222                 * Augment the base size for descriptors with optional and/or
 223                 * variable-length fields
 224                 */
 225                switch (resource->type) {
 226                case ACPI_RESOURCE_TYPE_IRQ:
 227
 228                        /* Length can be 3 or 2 */
 229
 230                        if (resource->data.irq.descriptor_length == 2) {
 231                                total_size--;
 232                        }
 233                        break;
 234
 235                case ACPI_RESOURCE_TYPE_START_DEPENDENT:
 236
 237                        /* Length can be 1 or 0 */
 238
 239                        if (resource->data.irq.descriptor_length == 0) {
 240                                total_size--;
 241                        }
 242                        break;
 243
 244                case ACPI_RESOURCE_TYPE_VENDOR:
 245                        /*
 246                         * Vendor Defined Resource:
 247                         * For a Vendor Specific resource, if the Length is between 1 and 7
 248                         * it will be created as a Small Resource data type, otherwise it
 249                         * is a Large Resource data type.
 250                         */
 251                        if (resource->data.vendor.byte_length > 7) {
 252
 253                                /* Base size of a Large resource descriptor */
 254
 255                                total_size =
 256                                    sizeof(struct aml_resource_large_header);
 257                        }
 258
 259                        /* Add the size of the vendor-specific data */
 260
 261                        total_size = (acpi_rs_length)
 262                            (total_size + resource->data.vendor.byte_length);
 263                        break;
 264
 265                case ACPI_RESOURCE_TYPE_END_TAG:
 266                        /*
 267                         * End Tag:
 268                         * We are done -- return the accumulated total size.
 269                         */
 270                        *size_needed = aml_size_needed + total_size;
 271
 272                        /* Normal exit */
 273
 274                        return_ACPI_STATUS(AE_OK);
 275
 276                case ACPI_RESOURCE_TYPE_ADDRESS16:
 277                        /*
 278                         * 16-Bit Address Resource:
 279                         * Add the size of the optional resource_source info
 280                         */
 281                        total_size = (acpi_rs_length) (total_size +
 282                                                       acpi_rs_struct_option_length
 283                                                       (&resource->data.
 284                                                        address16.
 285                                                        resource_source));
 286                        break;
 287
 288                case ACPI_RESOURCE_TYPE_ADDRESS32:
 289                        /*
 290                         * 32-Bit Address Resource:
 291                         * Add the size of the optional resource_source info
 292                         */
 293                        total_size = (acpi_rs_length) (total_size +
 294                                                       acpi_rs_struct_option_length
 295                                                       (&resource->data.
 296                                                        address32.
 297                                                        resource_source));
 298                        break;
 299
 300                case ACPI_RESOURCE_TYPE_ADDRESS64:
 301                        /*
 302                         * 64-Bit Address Resource:
 303                         * Add the size of the optional resource_source info
 304                         */
 305                        total_size = (acpi_rs_length) (total_size +
 306                                                       acpi_rs_struct_option_length
 307                                                       (&resource->data.
 308                                                        address64.
 309                                                        resource_source));
 310                        break;
 311
 312                case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
 313                        /*
 314                         * Extended IRQ Resource:
 315                         * Add the size of each additional optional interrupt beyond the
 316                         * required 1 (4 bytes for each u32 interrupt number)
 317                         */
 318                        total_size = (acpi_rs_length) (total_size +
 319                                                       ((resource->data.
 320                                                         extended_irq.
 321                                                         interrupt_count -
 322                                                         1) * 4) +
 323                                                       /* Add the size of the optional resource_source info */
 324                                                       acpi_rs_struct_option_length
 325                                                       (&resource->data.
 326                                                        extended_irq.
 327                                                        resource_source));
 328                        break;
 329
 330                case ACPI_RESOURCE_TYPE_GPIO:
 331
 332                        total_size = (acpi_rs_length) (total_size +
 333                                                       (resource->data.gpio.
 334                                                        pin_table_length * 2) +
 335                                                       resource->data.gpio.
 336                                                       resource_source.
 337                                                       string_length +
 338                                                       resource->data.gpio.
 339                                                       vendor_length);
 340
 341                        break;
 342
 343                case ACPI_RESOURCE_TYPE_SERIAL_BUS:
 344
 345                        total_size =
 346                            acpi_gbl_aml_resource_serial_bus_sizes[resource->
 347                                                                   data.
 348                                                                   common_serial_bus.
 349                                                                   type];
 350
 351                        total_size = (acpi_rs_length) (total_size +
 352                                                       resource->data.
 353                                                       i2c_serial_bus.
 354                                                       resource_source.
 355                                                       string_length +
 356                                                       resource->data.
 357                                                       i2c_serial_bus.
 358                                                       vendor_length);
 359
 360                        break;
 361
 362                default:
 363
 364                        break;
 365                }
 366
 367                /* Update the total */
 368
 369                aml_size_needed += total_size;
 370
 371                /* Point to the next object */
 372
 373                resource =
 374                    ACPI_ADD_PTR(struct acpi_resource, resource,
 375                                 resource->length);
 376        }
 377
 378        /* Did not find an end_tag resource descriptor */
 379
 380        return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
 381}
 382
 383/*******************************************************************************
 384 *
 385 * FUNCTION:    acpi_rs_get_list_length
 386 *
 387 * PARAMETERS:  aml_buffer          - Pointer to the resource byte stream
 388 *              aml_buffer_length   - Size of aml_buffer
 389 *              size_needed         - Where the size needed is returned
 390 *
 391 * RETURN:      Status
 392 *
 393 * DESCRIPTION: Takes an external resource byte stream and calculates the size
 394 *              buffer needed to hold the corresponding internal resource
 395 *              descriptor linked list.
 396 *
 397 ******************************************************************************/
 398
 399acpi_status
 400acpi_rs_get_list_length(u8 * aml_buffer,
 401                        u32 aml_buffer_length, acpi_size * size_needed)
 402{
 403        acpi_status status;
 404        u8 *end_aml;
 405        u8 *buffer;
 406        u32 buffer_size;
 407        u16 temp16;
 408        u16 resource_length;
 409        u32 extra_struct_bytes;
 410        u8 resource_index;
 411        u8 minimum_aml_resource_length;
 412        union aml_resource *aml_resource;
 413
 414        ACPI_FUNCTION_TRACE(rs_get_list_length);
 415
 416        *size_needed = ACPI_RS_SIZE_MIN;        /* Minimum size is one end_tag */
 417        end_aml = aml_buffer + aml_buffer_length;
 418
 419        /* Walk the list of AML resource descriptors */
 420
 421        while (aml_buffer < end_aml) {
 422
 423                /* Validate the Resource Type and Resource Length */
 424
 425                status =
 426                    acpi_ut_validate_resource(NULL, aml_buffer,
 427                                              &resource_index);
 428                if (ACPI_FAILURE(status)) {
 429                        /*
 430                         * Exit on failure. Cannot continue because the descriptor length
 431                         * may be bogus also.
 432                         */
 433                        return_ACPI_STATUS(status);
 434                }
 435
 436                aml_resource = (void *)aml_buffer;
 437
 438                /* Get the resource length and base (minimum) AML size */
 439
 440                resource_length = acpi_ut_get_resource_length(aml_buffer);
 441                minimum_aml_resource_length =
 442                    acpi_gbl_resource_aml_sizes[resource_index];
 443
 444                /*
 445                 * Augment the size for descriptors with optional
 446                 * and/or variable length fields
 447                 */
 448                extra_struct_bytes = 0;
 449                buffer =
 450                    aml_buffer + acpi_ut_get_resource_header_length(aml_buffer);
 451
 452                switch (acpi_ut_get_resource_type(aml_buffer)) {
 453                case ACPI_RESOURCE_NAME_IRQ:
 454                        /*
 455                         * IRQ Resource:
 456                         * Get the number of bits set in the 16-bit IRQ mask
 457                         */
 458                        ACPI_MOVE_16_TO_16(&temp16, buffer);
 459                        extra_struct_bytes = acpi_rs_count_set_bits(temp16);
 460                        break;
 461
 462                case ACPI_RESOURCE_NAME_DMA:
 463                        /*
 464                         * DMA Resource:
 465                         * Get the number of bits set in the 8-bit DMA mask
 466                         */
 467                        extra_struct_bytes = acpi_rs_count_set_bits(*buffer);
 468                        break;
 469
 470                case ACPI_RESOURCE_NAME_VENDOR_SMALL:
 471                case ACPI_RESOURCE_NAME_VENDOR_LARGE:
 472                        /*
 473                         * Vendor Resource:
 474                         * Get the number of vendor data bytes
 475                         */
 476                        extra_struct_bytes = resource_length;
 477
 478                        /*
 479                         * There is already one byte included in the minimum
 480                         * descriptor size. If there are extra struct bytes,
 481                         * subtract one from the count.
 482                         */
 483                        if (extra_struct_bytes) {
 484                                extra_struct_bytes--;
 485                        }
 486                        break;
 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                case ACPI_RESOURCE_NAME_ADDRESS32:
 495                case ACPI_RESOURCE_NAME_ADDRESS16:
 496                case ACPI_RESOURCE_NAME_ADDRESS64:
 497                        /*
 498                         * Address Resource:
 499                         * Add the size of the optional resource_source
 500                         */
 501                        extra_struct_bytes =
 502                            acpi_rs_stream_option_length(resource_length,
 503                                                         minimum_aml_resource_length);
 504                        break;
 505
 506                case ACPI_RESOURCE_NAME_EXTENDED_IRQ:
 507                        /*
 508                         * Extended IRQ Resource:
 509                         * Using the interrupt_table_length, add 4 bytes for each additional
 510                         * interrupt. Note: at least one interrupt is required and is
 511                         * included in the minimum descriptor size (reason for the -1)
 512                         */
 513                        extra_struct_bytes = (buffer[1] - 1) * sizeof(u32);
 514
 515                        /* Add the size of the optional resource_source */
 516
 517                        extra_struct_bytes +=
 518                            acpi_rs_stream_option_length(resource_length -
 519                                                         extra_struct_bytes,
 520                                                         minimum_aml_resource_length);
 521                        break;
 522
 523                case ACPI_RESOURCE_NAME_GPIO:
 524
 525                        /* Vendor data is optional */
 526
 527                        if (aml_resource->gpio.vendor_length) {
 528                                extra_struct_bytes +=
 529                                    aml_resource->gpio.vendor_offset -
 530                                    aml_resource->gpio.pin_table_offset +
 531                                    aml_resource->gpio.vendor_length;
 532                        } else {
 533                                extra_struct_bytes +=
 534                                    aml_resource->large_header.resource_length +
 535                                    sizeof(struct aml_resource_large_header) -
 536                                    aml_resource->gpio.pin_table_offset;
 537                        }
 538                        break;
 539
 540                case ACPI_RESOURCE_NAME_SERIAL_BUS:
 541
 542                        minimum_aml_resource_length =
 543                            acpi_gbl_resource_aml_serial_bus_sizes
 544                            [aml_resource->common_serial_bus.type];
 545                        extra_struct_bytes +=
 546                            aml_resource->common_serial_bus.resource_length -
 547                            minimum_aml_resource_length;
 548                        break;
 549
 550                default:
 551
 552                        break;
 553                }
 554
 555                /*
 556                 * Update the required buffer size for the internal descriptor structs
 557                 *
 558                 * Important: Round the size up for the appropriate alignment. This
 559                 * is a requirement on IA64.
 560                 */
 561                if (acpi_ut_get_resource_type(aml_buffer) ==
 562                    ACPI_RESOURCE_NAME_SERIAL_BUS) {
 563                        buffer_size =
 564                            acpi_gbl_resource_struct_serial_bus_sizes
 565                            [aml_resource->common_serial_bus.type] +
 566                            extra_struct_bytes;
 567                } else {
 568                        buffer_size =
 569                            acpi_gbl_resource_struct_sizes[resource_index] +
 570                            extra_struct_bytes;
 571                }
 572
 573                buffer_size = (u32)ACPI_ROUND_UP_TO_NATIVE_WORD(buffer_size);
 574                *size_needed += buffer_size;
 575
 576                ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES,
 577                                  "Type %.2X, AmlLength %.2X InternalLength %.2X\n",
 578                                  acpi_ut_get_resource_type(aml_buffer),
 579                                  acpi_ut_get_descriptor_length(aml_buffer),
 580                                  buffer_size));
 581
 582                /*
 583                 * Point to the next resource within the AML stream using the length
 584                 * contained in the resource descriptor header
 585                 */
 586                aml_buffer += acpi_ut_get_descriptor_length(aml_buffer);
 587        }
 588
 589        /* Did not find an end_tag resource descriptor */
 590
 591        return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
 592}
 593
 594/*******************************************************************************
 595 *
 596 * FUNCTION:    acpi_rs_get_pci_routing_table_length
 597 *
 598 * PARAMETERS:  package_object          - Pointer to the package object
 599 *              buffer_size_needed      - u32 pointer of the size buffer
 600 *                                        needed to properly return the
 601 *                                        parsed data
 602 *
 603 * RETURN:      Status
 604 *
 605 * DESCRIPTION: Given a package representing a PCI routing table, this
 606 *              calculates the size of the corresponding linked list of
 607 *              descriptions.
 608 *
 609 ******************************************************************************/
 610
 611acpi_status
 612acpi_rs_get_pci_routing_table_length(union acpi_operand_object *package_object,
 613                                     acpi_size * buffer_size_needed)
 614{
 615        u32 number_of_elements;
 616        acpi_size temp_size_needed = 0;
 617        union acpi_operand_object **top_object_list;
 618        u32 index;
 619        union acpi_operand_object *package_element;
 620        union acpi_operand_object **sub_object_list;
 621        u8 name_found;
 622        u32 table_index;
 623
 624        ACPI_FUNCTION_TRACE(rs_get_pci_routing_table_length);
 625
 626        number_of_elements = package_object->package.count;
 627
 628        /*
 629         * Calculate the size of the return buffer.
 630         * The base size is the number of elements * the sizes of the
 631         * structures. Additional space for the strings is added below.
 632         * The minus one is to subtract the size of the u8 Source[1]
 633         * member because it is added below.
 634         *
 635         * But each PRT_ENTRY structure has a pointer to a string and
 636         * the size of that string must be found.
 637         */
 638        top_object_list = package_object->package.elements;
 639
 640        for (index = 0; index < number_of_elements; index++) {
 641
 642                /* Dereference the subpackage */
 643
 644                package_element = *top_object_list;
 645
 646                /* We must have a valid Package object */
 647
 648                if (!package_element ||
 649                    (package_element->common.type != ACPI_TYPE_PACKAGE)) {
 650                        return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 651                }
 652
 653                /*
 654                 * The sub_object_list will now point to an array of the
 655                 * four IRQ elements: Address, Pin, Source and source_index
 656                 */
 657                sub_object_list = package_element->package.elements;
 658
 659                /* Scan the irq_table_elements for the Source Name String */
 660
 661                name_found = FALSE;
 662
 663                for (table_index = 0;
 664                     table_index < package_element->package.count
 665                     && !name_found; table_index++) {
 666                        if (*sub_object_list && /* Null object allowed */
 667                            ((ACPI_TYPE_STRING ==
 668                              (*sub_object_list)->common.type) ||
 669                             ((ACPI_TYPE_LOCAL_REFERENCE ==
 670                               (*sub_object_list)->common.type) &&
 671                              ((*sub_object_list)->reference.class ==
 672                               ACPI_REFCLASS_NAME)))) {
 673                                name_found = TRUE;
 674                        } else {
 675                                /* Look at the next element */
 676
 677                                sub_object_list++;
 678                        }
 679                }
 680
 681                temp_size_needed += (sizeof(struct acpi_pci_routing_table) - 4);
 682
 683                /* Was a String type found? */
 684
 685                if (name_found) {
 686                        if ((*sub_object_list)->common.type == ACPI_TYPE_STRING) {
 687                                /*
 688                                 * The length String.Length field does not include the
 689                                 * terminating NULL, add 1
 690                                 */
 691                                temp_size_needed += ((acpi_size)
 692                                                     (*sub_object_list)->string.
 693                                                     length + 1);
 694                        } else {
 695                                temp_size_needed += acpi_ns_get_pathname_length((*sub_object_list)->reference.node);
 696                        }
 697                } else {
 698                        /*
 699                         * If no name was found, then this is a NULL, which is
 700                         * translated as a u32 zero.
 701                         */
 702                        temp_size_needed += sizeof(u32);
 703                }
 704
 705                /* Round up the size since each element must be aligned */
 706
 707                temp_size_needed = ACPI_ROUND_UP_TO_64BIT(temp_size_needed);
 708
 709                /* Point to the next union acpi_operand_object */
 710
 711                top_object_list++;
 712        }
 713
 714        /*
 715         * Add an extra element to the end of the list, essentially a
 716         * NULL terminator
 717         */
 718        *buffer_size_needed =
 719            temp_size_needed + sizeof(struct acpi_pci_routing_table);
 720        return_ACPI_STATUS(AE_OK);
 721}
 722