drivers/acpi/acpica/utresrc.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: utresrc - Resource management utilities
   4  *
   5  ******************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2012, Intel Corp.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include <acpi/acpi.h>
  45 #include "accommon.h"
  46 #include "acresrc.h"
  47
  48 #define _COMPONENT          ACPI_UTILITIES
  49 ACPI_MODULE_NAME("utresrc")
  50 #if defined(ACPI_DISASSEMBLER) || defined (ACPI_DEBUGGER)
  51 /*
  52  * Strings used to decode resource descriptors.
  53  * Used by both the disassembler and the debugger resource dump routines
  54  */
  55 const char *acpi_gbl_bm_decode[] = {
  56         "NotBusMaster",
  57         "BusMaster"
  58 };
  59
  60 const char *acpi_gbl_config_decode[] = {
  61         "0 - Good Configuration",
  62         "1 - Acceptable Configuration",
  63         "2 - Suboptimal Configuration",
  64         "3 - ***Invalid Configuration***",
  65 };
  66
  67 const char *acpi_gbl_consume_decode[] = {
  68         "ResourceProducer",
  69         "ResourceConsumer"
  70 };
  71
  72 const char *acpi_gbl_dec_decode[] = {
  73         "PosDecode",
  74         "SubDecode"
  75 };
  76
  77 const char *acpi_gbl_he_decode[] = {
  78         "Level",
  79         "Edge"
  80 };
  81
  82 const char *acpi_gbl_io_decode[] = {
  83         "Decode10",
  84         "Decode16"
  85 };
  86
  87 const char *acpi_gbl_ll_decode[] = {
  88         "ActiveHigh",
  89         "ActiveLow"
  90 };
  91
  92 const char *acpi_gbl_max_decode[] = {
  93         "MaxNotFixed",
  94         "MaxFixed"
  95 };
  96
  97 const char *acpi_gbl_mem_decode[] = {
  98         "NonCacheable",
  99         "Cacheable",
 100         "WriteCombining",
 101         "Prefetchable"
 102 };
 103
 104 const char *acpi_gbl_min_decode[] = {
 105         "MinNotFixed",
 106         "MinFixed"
 107 };
 108
 109 const char *acpi_gbl_mtp_decode[] = {
 110         "AddressRangeMemory",
 111         "AddressRangeReserved",
 112         "AddressRangeACPI",
 113         "AddressRangeNVS"
 114 };
 115
 116 const char *acpi_gbl_rng_decode[] = {
 117         "InvalidRanges",
 118         "NonISAOnlyRanges",
 119         "ISAOnlyRanges",
 120         "EntireRange"
 121 };
 122
 123 const char *acpi_gbl_rw_decode[] = {
 124         "ReadOnly",
 125         "ReadWrite"
 126 };
 127
 128 const char *acpi_gbl_shr_decode[] = {
 129         "Exclusive",
 130         "Shared"
 131 };
 132
 133 const char *acpi_gbl_siz_decode[] = {
 134         "Transfer8",
 135         "Transfer8_16",
 136         "Transfer16",
 137         "InvalidSize"
 138 };
 139
 140 const char *acpi_gbl_trs_decode[] = {
 141         "DenseTranslation",
 142         "SparseTranslation"
 143 };
 144
 145 const char *acpi_gbl_ttp_decode[] = {
 146         "TypeStatic",
 147         "TypeTranslation"
 148 };
 149
 150 const char *acpi_gbl_typ_decode[] = {
 151         "Compatibility",
 152         "TypeA",
 153         "TypeB",
 154         "TypeF"
 155 };
 156
 157 const char *acpi_gbl_ppc_decode[] = {
 158         "PullDefault",
 159         "PullUp",
 160         "PullDown",
 161         "PullNone"
 162 };
 163
 164 const char *acpi_gbl_ior_decode[] = {
 165         "IoRestrictionNone",
 166         "IoRestrictionInputOnly",
 167         "IoRestrictionOutputOnly",
 168         "IoRestrictionNoneAndPreserve"
 169 };
 170
 171 const char *acpi_gbl_dts_decode[] = {
 172         "Width8bit",
 173         "Width16bit",
 174         "Width32bit",
 175         "Width64bit",
 176         "Width128bit",
 177         "Width256bit",
 178 };
 179
 180 /* GPIO connection type */
 181
 182 const char *acpi_gbl_ct_decode[] = {
 183         "Interrupt",
 184         "I/O"
 185 };
 186
 187 /* Serial bus type */
 188
 189 const char *acpi_gbl_sbt_decode[] = {
 190         "/* UNKNOWN serial bus type */",
 191         "I2C",
 192         "SPI",
 193         "UART"
 194 };
 195
 196 /* I2C serial bus access mode */
 197
 198 const char *acpi_gbl_am_decode[] = {
 199         "AddressingMode7Bit",
 200         "AddressingMode10Bit"
 201 };
 202
 203 /* I2C serial bus slave mode */
 204
 205 const char *acpi_gbl_sm_decode[] = {
 206         "ControllerInitiated",
 207         "DeviceInitiated"
 208 };
 209
 210 /* SPI serial bus wire mode */
 211
 212 const char *acpi_gbl_wm_decode[] = {
 213         "FourWireMode",
 214         "ThreeWireMode"
 215 };
 216
 217 /* SPI serial clock phase */
 218
 219 const char *acpi_gbl_cph_decode[] = {
 220         "ClockPhaseFirst",
 221         "ClockPhaseSecond"
 222 };
 223
 224 /* SPI serial bus clock polarity */
 225
 226 const char *acpi_gbl_cpo_decode[] = {
 227         "ClockPolarityLow",
 228         "ClockPolarityHigh"
 229 };
 230
 231 /* SPI serial bus device polarity */
 232
 233 const char *acpi_gbl_dp_decode[] = {
 234         "PolarityLow",
 235         "PolarityHigh"
 236 };
 237
 238 /* UART serial bus endian */
 239
 240 const char *acpi_gbl_ed_decode[] = {
 241         "LittleEndian",
 242         "BigEndian"
 243 };
 244
 245 /* UART serial bus bits per byte */
 246
 247 const char *acpi_gbl_bpb_decode[] = {
 248         "DataBitsFive",
 249         "DataBitsSix",
 250         "DataBitsSeven",
 251         "DataBitsEight",
 252         "DataBitsNine",
 253         "/* UNKNOWN Bits per byte */",
 254         "/* UNKNOWN Bits per byte */",
 255         "/* UNKNOWN Bits per byte */"
 256 };
 257
 258 /* UART serial bus stop bits */
 259
 260 const char *acpi_gbl_sb_decode[] = {
 261         "StopBitsNone",
 262         "StopBitsOne",
 263         "StopBitsOnePlusHalf",
 264         "StopBitsTwo"
 265 };
 266
 267 /* UART serial bus flow control */
 268
 269 const char *acpi_gbl_fc_decode[] = {
 270         "FlowControlNone",
 271         "FlowControlHardware",
 272         "FlowControlXON",
 273         "/* UNKNOWN flow control keyword */"
 274 };
 275
 276 /* UART serial bus parity type */
 277
 278 const char *acpi_gbl_pt_decode[] = {
 279         "ParityTypeNone",
 280         "ParityTypeEven",
 281         "ParityTypeOdd",
 282         "ParityTypeMark",
 283         "ParityTypeSpace",
 284         "/* UNKNOWN parity keyword */",
 285         "/* UNKNOWN parity keyword */",
 286         "/* UNKNOWN parity keyword */"
 287 };
 288
 289 #endif
 290
 291 /*
 292  * Base sizes of the raw AML resource descriptors, indexed by resource type.
 293  * Zero indicates a reserved (and therefore invalid) resource type.
 294  */
 295 const u8 acpi_gbl_resource_aml_sizes[] = {
 296         /* Small descriptors */
 297
 298         0,
 299         0,
 300         0,
 301         0,
 302         ACPI_AML_SIZE_SMALL(struct aml_resource_irq),
 303         ACPI_AML_SIZE_SMALL(struct aml_resource_dma),
 304         ACPI_AML_SIZE_SMALL(struct aml_resource_start_dependent),
 305         ACPI_AML_SIZE_SMALL(struct aml_resource_end_dependent),
 306         ACPI_AML_SIZE_SMALL(struct aml_resource_io),
 307         ACPI_AML_SIZE_SMALL(struct aml_resource_fixed_io),
 308         ACPI_AML_SIZE_SMALL(struct aml_resource_fixed_dma),
 309         0,
 310         0,
 311         0,
 312         ACPI_AML_SIZE_SMALL(struct aml_resource_vendor_small),
 313         ACPI_AML_SIZE_SMALL(struct aml_resource_end_tag),
 314
 315         /* Large descriptors */
 316
 317         0,
 318         ACPI_AML_SIZE_LARGE(struct aml_resource_memory24),
 319         ACPI_AML_SIZE_LARGE(struct aml_resource_generic_register),
 320         0,
 321         ACPI_AML_SIZE_LARGE(struct aml_resource_vendor_large),
 322         ACPI_AML_SIZE_LARGE(struct aml_resource_memory32),
 323         ACPI_AML_SIZE_LARGE(struct aml_resource_fixed_memory32),
 324         ACPI_AML_SIZE_LARGE(struct aml_resource_address32),
 325         ACPI_AML_SIZE_LARGE(struct aml_resource_address16),
 326         ACPI_AML_SIZE_LARGE(struct aml_resource_extended_irq),
 327         ACPI_AML_SIZE_LARGE(struct aml_resource_address64),
 328         ACPI_AML_SIZE_LARGE(struct aml_resource_extended_address64),
 329         ACPI_AML_SIZE_LARGE(struct aml_resource_gpio),
 330         0,
 331         ACPI_AML_SIZE_LARGE(struct aml_resource_common_serialbus),
 332 };
 333
 334 const u8 acpi_gbl_resource_aml_serial_bus_sizes[] = {
 335         0,
 336         ACPI_AML_SIZE_LARGE(struct aml_resource_i2c_serialbus),
 337         ACPI_AML_SIZE_LARGE(struct aml_resource_spi_serialbus),
 338         ACPI_AML_SIZE_LARGE(struct aml_resource_uart_serialbus),
 339 };
 340
 341 /*
 342  * Resource types, used to validate the resource length field.
 343  * The length of fixed-length types must match exactly, variable
 344  * lengths must meet the minimum required length, etc.
 345  * Zero indicates a reserved (and therefore invalid) resource type.
 346  */
 347 static const u8 acpi_gbl_resource_types[] = {
 348         /* Small descriptors */
 349
 350         0,
 351         0,
 352         0,
 353         0,
 354         ACPI_SMALL_VARIABLE_LENGTH,     /* 04 IRQ */
 355         ACPI_FIXED_LENGTH,      /* 05 DMA */
 356         ACPI_SMALL_VARIABLE_LENGTH,     /* 06 start_dependent_functions */
 357         ACPI_FIXED_LENGTH,      /* 07 end_dependent_functions */
 358         ACPI_FIXED_LENGTH,      /* 08 IO */
 359         ACPI_FIXED_LENGTH,      /* 09 fixed_iO */
 360         ACPI_FIXED_LENGTH,      /* 0_a fixed_dMA */
 361         0,
 362         0,
 363         0,
 364         ACPI_VARIABLE_LENGTH,   /* 0_e vendor_short */
 365         ACPI_FIXED_LENGTH,      /* 0_f end_tag */
 366
 367         /* Large descriptors */
 368
 369         0,
 370         ACPI_FIXED_LENGTH,      /* 01 Memory24 */
 371         ACPI_FIXED_LENGTH,      /* 02 generic_register */
 372         0,
 373         ACPI_VARIABLE_LENGTH,   /* 04 vendor_long */
 374         ACPI_FIXED_LENGTH,      /* 05 Memory32 */
 375         ACPI_FIXED_LENGTH,      /* 06 memory32_fixed */
 376         ACPI_VARIABLE_LENGTH,   /* 07 Dword* address */
 377         ACPI_VARIABLE_LENGTH,   /* 08 Word* address */
 378         ACPI_VARIABLE_LENGTH,   /* 09 extended_iRQ */
 379         ACPI_VARIABLE_LENGTH,   /* 0_a Qword* address */
 380         ACPI_FIXED_LENGTH,      /* 0_b Extended* address */
 381         ACPI_VARIABLE_LENGTH,   /* 0_c Gpio* */
 382         0,
 383         ACPI_VARIABLE_LENGTH    /* 0_e *serial_bus */
 384 };
 385
 386 /*
 387  * For the i_aSL compiler/disassembler, we don't want any error messages
 388  * because the disassembler uses the resource validation code to determine
 389  * if Buffer objects are actually Resource Templates.
 390  */
 391 #ifdef ACPI_ASL_COMPILER
 392 #define ACPI_RESOURCE_ERROR(plist)
 393 #else
 394 #define ACPI_RESOURCE_ERROR(plist)  ACPI_ERROR(plist)
 395 #endif
 396
 397 /*******************************************************************************
 398  *
 399  * FUNCTION:    acpi_ut_walk_aml_resources
 400  *
 401  * PARAMETERS:  Aml             - Pointer to the raw AML resource template
 402  *              aml_length      - Length of the entire template
 403  *              user_function   - Called once for each descriptor found. If
 404  *                                NULL, a pointer to the end_tag is returned
 405  *              Context         - Passed to user_function
 406  *
 407  * RETURN:      Status
 408  *
 409  * DESCRIPTION: Walk a raw AML resource list(buffer). User function called
 410  *              once for each resource found.
 411  *
 412  ******************************************************************************/
 413
 414 acpi_status
 415 acpi_ut_walk_aml_resources(u8 * aml,
 416                            acpi_size aml_length,
 417                            acpi_walk_aml_callback user_function, void **context)
 418 {
 419         acpi_status status;
 420         u8 *end_aml;
 421         u8 resource_index;
 422         u32 length;
 423         u32 offset = 0;
 424         u8 end_tag[2] = { 0x79, 0x00 };
 425
 426         ACPI_FUNCTION_TRACE(ut_walk_aml_resources);
 427
 428         /* The absolute minimum resource template is one end_tag descriptor */
 429
 430         if (aml_length < sizeof(struct aml_resource_end_tag)) {
 431                 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
 432         }
 433
 434         /* Point to the end of the resource template buffer */
 435
 436         end_aml = aml + aml_length;
 437
 438         /* Walk the byte list, abort on any invalid descriptor type or length */
 439
 440         while (aml < end_aml) {
 441
 442                 /* Validate the Resource Type and Resource Length */
 443
 444                 status = acpi_ut_validate_resource(aml, &resource_index);
 445                 if (ACPI_FAILURE(status)) {
 446                         /*
 447                          * Exit on failure. Cannot continue because the descriptor length
 448                          * may be bogus also.
 449                          */
 450                         return_ACPI_STATUS(status);
 451                 }
 452
 453                 /* Get the length of this descriptor */
 454
 455                 length = acpi_ut_get_descriptor_length(aml);
 456
 457                 /* Invoke the user function */
 458
 459                 if (user_function) {
 460                         status =
 461                             user_function(aml, length, offset, resource_index,
 462                                           context);
 463                         if (ACPI_FAILURE(status)) {
 464                                 return_ACPI_STATUS(status);
 465                         }
 466                 }
 467
 468                 /* An end_tag descriptor terminates this resource template */
 469
 470                 if (acpi_ut_get_resource_type(aml) ==
 471                     ACPI_RESOURCE_NAME_END_TAG) {
 472                         /*
 473                          * There must be at least one more byte in the buffer for
 474                          * the 2nd byte of the end_tag
 475                          */
 476                         if ((aml + 1) >= end_aml) {
 477                                 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
 478                         }
 479
 480                         /* Return the pointer to the end_tag if requested */
 481
 482                         if (!user_function) {
 483                                 *context = aml;
 484                         }
 485
 486                         /* Normal exit */
 487
 488                         return_ACPI_STATUS(AE_OK);
 489                 }
 490
 491                 aml += length;
 492                 offset += length;
 493         }
 494
 495         /* Did not find an end_tag descriptor */
 496
 497         if (user_function) {
 498
 499                 /* Insert an end_tag anyway. acpi_rs_get_list_length always leaves room */
 500
 501                 (void)acpi_ut_validate_resource(end_tag, &resource_index);
 502                 status =
 503                     user_function(end_tag, 2, offset, resource_index, context);
 504                 if (ACPI_FAILURE(status)) {
 505                         return_ACPI_STATUS(status);
 506                 }
 507         }
 508
 509         return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
 510 }
 511
 512 /*******************************************************************************
 513  *
 514  * FUNCTION:    acpi_ut_validate_resource
 515  *
 516  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
 517  *              return_index    - Where the resource index is returned. NULL
 518  *                                if the index is not required.
 519  *
 520  * RETURN:      Status, and optionally the Index into the global resource tables
 521  *
 522  * DESCRIPTION: Validate an AML resource descriptor by checking the Resource
 523  *              Type and Resource Length. Returns an index into the global
 524  *              resource information/dispatch tables for later use.
 525  *
 526  ******************************************************************************/
 527
 528 acpi_status acpi_ut_validate_resource(void *aml, u8 * return_index)
 529 {
 530         union aml_resource *aml_resource;
 531         u8 resource_type;
 532         u8 resource_index;
 533         acpi_rs_length resource_length;
 534         acpi_rs_length minimum_resource_length;
 535
 536         ACPI_FUNCTION_ENTRY();
 537
 538         /*
 539          * 1) Validate the resource_type field (Byte 0)
 540          */
 541         resource_type = ACPI_GET8(aml);
 542
 543         /*
 544          * Byte 0 contains the descriptor name (Resource Type)
 545          * Examine the large/small bit in the resource header
 546          */
 547         if (resource_type & ACPI_RESOURCE_NAME_LARGE) {
 548
 549                 /* Verify the large resource type (name) against the max */
 550
 551                 if (resource_type > ACPI_RESOURCE_NAME_LARGE_MAX) {
 552                         goto invalid_resource;
 553                 }
 554
 555                 /*
 556                  * Large Resource Type -- bits 6:0 contain the name
 557                  * Translate range 0x80-0x8B to index range 0x10-0x1B
 558                  */
 559                 resource_index = (u8) (resource_type - 0x70);
 560         } else {
 561                 /*
 562                  * Small Resource Type -- bits 6:3 contain the name
 563                  * Shift range to index range 0x00-0x0F
 564                  */
 565                 resource_index = (u8)
 566                     ((resource_type & ACPI_RESOURCE_NAME_SMALL_MASK) >> 3);
 567         }
 568
 569         /*
 570          * Check validity of the resource type, via acpi_gbl_resource_types. Zero
 571          * indicates an invalid resource.
 572          */
 573         if (!acpi_gbl_resource_types[resource_index]) {
 574                 goto invalid_resource;
 575         }
 576
 577         /*
 578          * Validate the resource_length field. This ensures that the length
 579          * is at least reasonable, and guarantees that it is non-zero.
 580          */
 581         resource_length = acpi_ut_get_resource_length(aml);
 582         minimum_resource_length = acpi_gbl_resource_aml_sizes[resource_index];
 583
 584         /* Validate based upon the type of resource - fixed length or variable */
 585
 586         switch (acpi_gbl_resource_types[resource_index]) {
 587         case ACPI_FIXED_LENGTH:
 588
 589                 /* Fixed length resource, length must match exactly */
 590
 591                 if (resource_length != minimum_resource_length) {
 592                         goto bad_resource_length;
 593                 }
 594                 break;
 595
 596         case ACPI_VARIABLE_LENGTH:
 597
 598                 /* Variable length resource, length must be at least the minimum */
 599
 600                 if (resource_length < minimum_resource_length) {
 601                         goto bad_resource_length;
 602                 }
 603                 break;
 604
 605         case ACPI_SMALL_VARIABLE_LENGTH:
 606
 607                 /* Small variable length resource, length can be (Min) or (Min-1) */
 608
 609                 if ((resource_length > minimum_resource_length) ||
 610                     (resource_length < (minimum_resource_length - 1))) {
 611                         goto bad_resource_length;
 612                 }
 613                 break;
 614
 615         default:
 616
 617                 /* Shouldn't happen (because of validation earlier), but be sure */
 618
 619                 goto invalid_resource;
 620         }
 621
 622         aml_resource = ACPI_CAST_PTR(union aml_resource, aml);
 623         if (resource_type == ACPI_RESOURCE_NAME_SERIAL_BUS) {
 624
 625                 /* Validate the bus_type field */
 626
 627                 if ((aml_resource->common_serial_bus.type == 0) ||
 628                     (aml_resource->common_serial_bus.type >
 629                      AML_RESOURCE_MAX_SERIALBUSTYPE)) {
 630                         ACPI_RESOURCE_ERROR((AE_INFO,
 631                                              "Invalid/unsupported SerialBus resource descriptor: BusType 0x%2.2X",
 632                                              aml_resource->common_serial_bus.
 633                                              type));
 634                         return (AE_AML_INVALID_RESOURCE_TYPE);
 635                 }
 636         }
 637
 638         /* Optionally return the resource table index */
 639
 640         if (return_index) {
 641                 *return_index = resource_index;
 642         }
 643
 644         return (AE_OK);
 645
 646       invalid_resource:
 647
 648         ACPI_RESOURCE_ERROR((AE_INFO,
 649                              "Invalid/unsupported resource descriptor: Type 0x%2.2X",
 650                              resource_type));
 651         return (AE_AML_INVALID_RESOURCE_TYPE);
 652
 653       bad_resource_length:
 654
 655         ACPI_RESOURCE_ERROR((AE_INFO,
 656                              "Invalid resource descriptor length: Type "
 657                              "0x%2.2X, Length 0x%4.4X, MinLength 0x%4.4X",
 658                              resource_type, resource_length,
 659                              minimum_resource_length));
 660         return (AE_AML_BAD_RESOURCE_LENGTH);
 661 }
 662
 663 /*******************************************************************************
 664  *
 665  * FUNCTION:    acpi_ut_get_resource_type
 666  *
 667  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
 668  *
 669  * RETURN:      The Resource Type with no extraneous bits (except the
 670  *              Large/Small descriptor bit -- this is left alone)
 671  *
 672  * DESCRIPTION: Extract the Resource Type/Name from the first byte of
 673  *              a resource descriptor.
 674  *
 675  ******************************************************************************/
 676
 677 u8 acpi_ut_get_resource_type(void *aml)
 678 {
 679         ACPI_FUNCTION_ENTRY();
 680
 681         /*
 682          * Byte 0 contains the descriptor name (Resource Type)
 683          * Examine the large/small bit in the resource header
 684          */
 685         if (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_LARGE) {
 686
 687                 /* Large Resource Type -- bits 6:0 contain the name */
 688
 689                 return (ACPI_GET8(aml));
 690         } else {
 691                 /* Small Resource Type -- bits 6:3 contain the name */
 692
 693                 return ((u8) (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_SMALL_MASK));
 694         }
 695 }
 696
 697 /*******************************************************************************
 698  *
 699  * FUNCTION:    acpi_ut_get_resource_length
 700  *
 701  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
 702  *
 703  * RETURN:      Byte Length
 704  *
 705  * DESCRIPTION: Get the "Resource Length" of a raw AML descriptor. By
 706  *              definition, this does not include the size of the descriptor
 707  *              header or the length field itself.
 708  *
 709  ******************************************************************************/
 710
 711 u16 acpi_ut_get_resource_length(void *aml)
 712 {
 713         acpi_rs_length resource_length;
 714
 715         ACPI_FUNCTION_ENTRY();
 716
 717         /*
 718          * Byte 0 contains the descriptor name (Resource Type)
 719          * Examine the large/small bit in the resource header
 720          */
 721         if (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_LARGE) {
 722
 723                 /* Large Resource type -- bytes 1-2 contain the 16-bit length */
 724
 725                 ACPI_MOVE_16_TO_16(&resource_length, ACPI_ADD_PTR(u8, aml, 1));
 726
 727         } else {
 728                 /* Small Resource type -- bits 2:0 of byte 0 contain the length */
 729
 730                 resource_length = (u16) (ACPI_GET8(aml) &
 731                                          ACPI_RESOURCE_NAME_SMALL_LENGTH_MASK);
 732         }
 733
 734         return (resource_length);
 735 }
 736
 737 /*******************************************************************************
 738  *
 739  * FUNCTION:    acpi_ut_get_resource_header_length
 740  *
 741  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
 742  *
 743  * RETURN:      Length of the AML header (depends on large/small descriptor)
 744  *
 745  * DESCRIPTION: Get the length of the header for this resource.
 746  *
 747  ******************************************************************************/
 748
 749 u8 acpi_ut_get_resource_header_length(void *aml)
 750 {
 751         ACPI_FUNCTION_ENTRY();
 752
 753         /* Examine the large/small bit in the resource header */
 754
 755         if (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_LARGE) {
 756                 return (sizeof(struct aml_resource_large_header));
 757         } else {
 758                 return (sizeof(struct aml_resource_small_header));
 759         }
 760 }
 761
 762 /*******************************************************************************
 763  *
 764  * FUNCTION:    acpi_ut_get_descriptor_length
 765  *
 766  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
 767  *
 768  * RETURN:      Byte length
 769  *
 770  * DESCRIPTION: Get the total byte length of a raw AML descriptor, including the
 771  *              length of the descriptor header and the length field itself.
 772  *              Used to walk descriptor lists.
 773  *
 774  ******************************************************************************/
 775
 776 u32 acpi_ut_get_descriptor_length(void *aml)
 777 {
 778         ACPI_FUNCTION_ENTRY();
 779
 780         /*
 781          * Get the Resource Length (does not include header length) and add
 782          * the header length (depends on if this is a small or large resource)
 783          */
 784         return (acpi_ut_get_resource_length(aml) +
 785                 acpi_ut_get_resource_header_length(aml));
 786 }
 787
 788 /*******************************************************************************
 789  *
 790  * FUNCTION:    acpi_ut_get_resource_end_tag
 791  *
 792  * PARAMETERS:  obj_desc        - The resource template buffer object
 793  *              end_tag         - Where the pointer to the end_tag is returned
 794  *
 795  * RETURN:      Status, pointer to the end tag
 796  *
 797  * DESCRIPTION: Find the end_tag resource descriptor in an AML resource template
 798  *              Note: allows a buffer length of zero.
 799  *
 800  ******************************************************************************/
 801
 802 acpi_status
 803 acpi_ut_get_resource_end_tag(union acpi_operand_object * obj_desc,
 804                              u8 ** end_tag)
 805 {
 806         acpi_status status;
 807
 808         ACPI_FUNCTION_TRACE(ut_get_resource_end_tag);
 809
 810         /* Allow a buffer length of zero */
 811
 812         if (!obj_desc->buffer.length) {
 813                 *end_tag = obj_desc->buffer.pointer;
 814                 return_ACPI_STATUS(AE_OK);
 815         }
 816
 817         /* Validate the template and get a pointer to the end_tag */
 818
 819         status = acpi_ut_walk_aml_resources(obj_desc->buffer.pointer,
 820                                             obj_desc->buffer.length, NULL,
 821                                             (void **)end_tag);
 822
 823         return_ACPI_STATUS(status);
 824 }