drivers/acpi/utilities/utresrc.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: utresrc - Resource managment utilities
   4  *
   5  ******************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2005, R. Byron Moore
   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 <acpi/amlresrc.h>
  46
  47 #define _COMPONENT          ACPI_UTILITIES
  48 ACPI_MODULE_NAME("utmisc")
  49
  50 /*
  51  * Base sizes of the raw AML resource descriptors, indexed by resource type.
  52  * Zero indicates a reserved (and therefore invalid) resource type.
  53  */
  54 const u8 acpi_gbl_resource_aml_sizes[] = {
  55         /* Small descriptors */
  56
  57         0,
  58         0,
  59         0,
  60         0,
  61         ACPI_AML_SIZE_SMALL(struct aml_resource_irq),
  62         ACPI_AML_SIZE_SMALL(struct aml_resource_dma),
  63         ACPI_AML_SIZE_SMALL(struct aml_resource_start_dependent),
  64         ACPI_AML_SIZE_SMALL(struct aml_resource_end_dependent),
  65         ACPI_AML_SIZE_SMALL(struct aml_resource_io),
  66         ACPI_AML_SIZE_SMALL(struct aml_resource_fixed_io),
  67         0,
  68         0,
  69         0,
  70         0,
  71         ACPI_AML_SIZE_SMALL(struct aml_resource_vendor_small),
  72         ACPI_AML_SIZE_SMALL(struct aml_resource_end_tag),
  73
  74         /* Large descriptors */
  75
  76         0,
  77         ACPI_AML_SIZE_LARGE(struct aml_resource_memory24),
  78         ACPI_AML_SIZE_LARGE(struct aml_resource_generic_register),
  79         0,
  80         ACPI_AML_SIZE_LARGE(struct aml_resource_vendor_large),
  81         ACPI_AML_SIZE_LARGE(struct aml_resource_memory32),
  82         ACPI_AML_SIZE_LARGE(struct aml_resource_fixed_memory32),
  83         ACPI_AML_SIZE_LARGE(struct aml_resource_address32),
  84         ACPI_AML_SIZE_LARGE(struct aml_resource_address16),
  85         ACPI_AML_SIZE_LARGE(struct aml_resource_extended_irq),
  86         ACPI_AML_SIZE_LARGE(struct aml_resource_address64),
  87         ACPI_AML_SIZE_LARGE(struct aml_resource_extended_address64)
  88 };
  89
  90 /*
  91  * Resource types, used to validate the resource length field.
  92  * The length of fixed-length types must match exactly, variable
  93  * lengths must meet the minimum required length, etc.
  94  * Zero indicates a reserved (and therefore invalid) resource type.
  95  */
  96 static const u8 acpi_gbl_resource_types[] = {
  97         /* Small descriptors */
  98
  99         0,
 100         0,
 101         0,
 102         0,
 103         ACPI_SMALL_VARIABLE_LENGTH,
 104         ACPI_FIXED_LENGTH,
 105         ACPI_SMALL_VARIABLE_LENGTH,
 106         ACPI_FIXED_LENGTH,
 107         ACPI_FIXED_LENGTH,
 108         ACPI_FIXED_LENGTH,
 109         0,
 110         0,
 111         0,
 112         0,
 113         ACPI_VARIABLE_LENGTH,
 114         ACPI_FIXED_LENGTH,
 115
 116         /* Large descriptors */
 117
 118         0,
 119         ACPI_FIXED_LENGTH,
 120         ACPI_FIXED_LENGTH,
 121         0,
 122         ACPI_VARIABLE_LENGTH,
 123         ACPI_FIXED_LENGTH,
 124         ACPI_FIXED_LENGTH,
 125         ACPI_VARIABLE_LENGTH,
 126         ACPI_VARIABLE_LENGTH,
 127         ACPI_VARIABLE_LENGTH,
 128         ACPI_VARIABLE_LENGTH,
 129         ACPI_FIXED_LENGTH
 130 };
 131
 132 /*******************************************************************************
 133  *
 134  * FUNCTION:    acpi_ut_validate_resource
 135  *
 136  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
 137  *              return_index    - Where the resource index is returned. NULL
 138  *                                if the index is not required.
 139  *
 140  * RETURN:      Status, and optionally the Index into the global resource tables
 141  *
 142  * DESCRIPTION: Validate an AML resource descriptor by checking the Resource
 143  *              Type and Resource Length. Returns an index into the global
 144  *              resource information/dispatch tables for later use.
 145  *
 146  ******************************************************************************/
 147
 148 acpi_status acpi_ut_validate_resource(void *aml, u8 * return_index)
 149 {
 150         u8 resource_type;
 151         u8 resource_index;
 152         acpi_rs_length resource_length;
 153         acpi_rs_length minimum_resource_length;
 154
 155         ACPI_FUNCTION_ENTRY();
 156
 157         /*
 158          * 1) Validate the resource_type field (Byte 0)
 159          */
 160         resource_type = *((u8 *) aml);
 161
 162         /*
 163          * Byte 0 contains the descriptor name (Resource Type)
 164          * Examine the large/small bit in the resource header
 165          */
 166         if (resource_type & ACPI_RESOURCE_NAME_LARGE) {
 167                 /* Verify the large resource type (name) against the max */
 168
 169                 if (resource_type > ACPI_RESOURCE_NAME_LARGE_MAX) {
 170                         return (AE_AML_INVALID_RESOURCE_TYPE);
 171                 }
 172
 173                 /*
 174                  * Large Resource Type -- bits 6:0 contain the name
 175                  * Translate range 0x80-0x8B to index range 0x10-0x1B
 176                  */
 177                 resource_index = (u8) (resource_type - 0x70);
 178         } else {
 179                 /*
 180                  * Small Resource Type -- bits 6:3 contain the name
 181                  * Shift range to index range 0x00-0x0F
 182                  */
 183                 resource_index = (u8)
 184                     ((resource_type & ACPI_RESOURCE_NAME_SMALL_MASK) >> 3);
 185         }
 186
 187         /* Check validity of the resource type, zero indicates name is invalid */
 188
 189         if (!acpi_gbl_resource_types[resource_index]) {
 190                 return (AE_AML_INVALID_RESOURCE_TYPE);
 191         }
 192
 193         /*
 194          * 2) Validate the resource_length field. This ensures that the length
 195          *    is at least reasonable, and guarantees that it is non-zero.
 196          */
 197         resource_length = acpi_ut_get_resource_length(aml);
 198         minimum_resource_length = acpi_gbl_resource_aml_sizes[resource_index];
 199
 200         /* Validate based upon the type of resource - fixed length or variable */
 201
 202         switch (acpi_gbl_resource_types[resource_index]) {
 203         case ACPI_FIXED_LENGTH:
 204
 205                 /* Fixed length resource, length must match exactly */
 206
 207                 if (resource_length != minimum_resource_length) {
 208                         return (AE_AML_BAD_RESOURCE_LENGTH);
 209                 }
 210                 break;
 211
 212         case ACPI_VARIABLE_LENGTH:
 213
 214                 /* Variable length resource, length must be at least the minimum */
 215
 216                 if (resource_length < minimum_resource_length) {
 217                         return (AE_AML_BAD_RESOURCE_LENGTH);
 218                 }
 219                 break;
 220
 221         case ACPI_SMALL_VARIABLE_LENGTH:
 222
 223                 /* Small variable length resource, length can be (Min) or (Min-1) */
 224
 225                 if ((resource_length > minimum_resource_length) ||
 226                     (resource_length < (minimum_resource_length - 1))) {
 227                         return (AE_AML_BAD_RESOURCE_LENGTH);
 228                 }
 229                 break;
 230
 231         default:
 232
 233                 /* Shouldn't happen (because of validation earlier), but be sure */
 234
 235                 return (AE_AML_INVALID_RESOURCE_TYPE);
 236         }
 237
 238         /* Optionally return the resource table index */
 239
 240         if (return_index) {
 241                 *return_index = resource_index;
 242         }
 243
 244         return (AE_OK);
 245 }
 246
 247 /*******************************************************************************
 248  *
 249  * FUNCTION:    acpi_ut_get_resource_type
 250  *
 251  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
 252  *
 253  * RETURN:      The Resource Type with no extraneous bits (except the
 254  *              Large/Small descriptor bit -- this is left alone)
 255  *
 256  * DESCRIPTION: Extract the Resource Type/Name from the first byte of
 257  *              a resource descriptor.
 258  *
 259  ******************************************************************************/
 260
 261 u8 acpi_ut_get_resource_type(void *aml)
 262 {
 263         ACPI_FUNCTION_ENTRY();
 264
 265         /*
 266          * Byte 0 contains the descriptor name (Resource Type)
 267          * Examine the large/small bit in the resource header
 268          */
 269         if (*((u8 *) aml) & ACPI_RESOURCE_NAME_LARGE) {
 270                 /* Large Resource Type -- bits 6:0 contain the name */
 271
 272                 return (*((u8 *) aml));
 273         } else {
 274                 /* Small Resource Type -- bits 6:3 contain the name */
 275
 276                 return ((u8) (*((u8 *) aml) & ACPI_RESOURCE_NAME_SMALL_MASK));
 277         }
 278 }
 279
 280 /*******************************************************************************
 281  *
 282  * FUNCTION:    acpi_ut_get_resource_length
 283  *
 284  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
 285  *
 286  * RETURN:      Byte Length
 287  *
 288  * DESCRIPTION: Get the "Resource Length" of a raw AML descriptor. By
 289  *              definition, this does not include the size of the descriptor
 290  *              header or the length field itself.
 291  *
 292  ******************************************************************************/
 293
 294 u16 acpi_ut_get_resource_length(void *aml)
 295 {
 296         acpi_rs_length resource_length;
 297
 298         ACPI_FUNCTION_ENTRY();
 299
 300         /*
 301          * Byte 0 contains the descriptor name (Resource Type)
 302          * Examine the large/small bit in the resource header
 303          */
 304         if (*((u8 *) aml) & ACPI_RESOURCE_NAME_LARGE) {
 305                 /* Large Resource type -- bytes 1-2 contain the 16-bit length */
 306
 307                 ACPI_MOVE_16_TO_16(&resource_length, &((u8 *) aml)[1]);
 308
 309         } else {
 310                 /* Small Resource type -- bits 2:0 of byte 0 contain the length */
 311
 312                 resource_length = (u16) (*((u8 *) aml) &
 313                                          ACPI_RESOURCE_NAME_SMALL_LENGTH_MASK);
 314         }
 315
 316         return (resource_length);
 317 }
 318
 319 /*******************************************************************************
 320  *
 321  * FUNCTION:    acpi_ut_get_resource_header_length
 322  *
 323  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
 324  *
 325  * RETURN:      Length of the AML header (depends on large/small descriptor)
 326  *
 327  * DESCRIPTION: Get the length of the header for this resource.
 328  *
 329  ******************************************************************************/
 330
 331 u8 acpi_ut_get_resource_header_length(void *aml)
 332 {
 333         ACPI_FUNCTION_ENTRY();
 334
 335         /* Examine the large/small bit in the resource header */
 336
 337         if (*((u8 *) aml) & ACPI_RESOURCE_NAME_LARGE) {
 338                 return (sizeof(struct aml_resource_large_header));
 339         } else {
 340                 return (sizeof(struct aml_resource_small_header));
 341         }
 342 }
 343
 344 /*******************************************************************************
 345  *
 346  * FUNCTION:    acpi_ut_get_descriptor_length
 347  *
 348  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
 349  *
 350  * RETURN:      Byte length
 351  *
 352  * DESCRIPTION: Get the total byte length of a raw AML descriptor, including the
 353  *              length of the descriptor header and the length field itself.
 354  *              Used to walk descriptor lists.
 355  *
 356  ******************************************************************************/
 357
 358 u32 acpi_ut_get_descriptor_length(void *aml)
 359 {
 360         ACPI_FUNCTION_ENTRY();
 361
 362         /*
 363          * Get the Resource Length (does not include header length) and add
 364          * the header length (depends on if this is a small or large resource)
 365          */
 366         return (acpi_ut_get_resource_length(aml) +
 367                 acpi_ut_get_resource_header_length(aml));
 368 }
 369
 370 /*******************************************************************************
 371  *
 372  * FUNCTION:    acpi_ut_get_resource_end_tag
 373  *
 374  * PARAMETERS:  obj_desc        - The resource template buffer object
 375  *
 376  * RETURN:      Pointer to the end tag
 377  *
 378  * DESCRIPTION: Find the end_tag resource descriptor in an AML resource template
 379  *
 380  ******************************************************************************/
 381
 382 acpi_status
 383 acpi_ut_get_resource_end_tag(union acpi_operand_object * obj_desc,
 384                              u8 ** end_tag)
 385 {
 386         acpi_status status;
 387         u8 *aml;
 388         u8 *end_aml;
 389
 390         ACPI_FUNCTION_TRACE("ut_get_resource_end_tag");
 391
 392         /* Get start and end pointers */
 393
 394         aml = obj_desc->buffer.pointer;
 395         end_aml = aml + obj_desc->buffer.length;
 396
 397         /* Walk the resource template, one descriptor per iteration */
 398
 399         while (aml < end_aml) {
 400                 /* Validate the Resource Type and Resource Length */
 401
 402                 status = acpi_ut_validate_resource(aml, NULL);
 403                 if (ACPI_FAILURE(status)) {
 404                         return_ACPI_STATUS(status);
 405                 }
 406
 407                 /* end_tag resource indicates the end of the resource template */
 408
 409                 if (acpi_ut_get_resource_type(aml) ==
 410                     ACPI_RESOURCE_NAME_END_TAG) {
 411                         /* Return the pointer to the end_tag */
 412
 413                         *end_tag = aml;
 414                         return_ACPI_STATUS(AE_OK);
 415                 }
 416
 417                 /*
 418                  * Point to the next resource descriptor in the AML buffer. The
 419                  * descriptor length is guaranteed to be non-zero by resource
 420                  * validation above.
 421                  */
 422                 aml += acpi_ut_get_descriptor_length(aml);
 423         }
 424
 425         /* Did not find an end_tag resource descriptor */
 426
 427         return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
 428 }