git.oblomov.eu Git - linux-2.6/blob - drivers/acpi/executer/exconvrt.c

   1 /******************************************************************************
   2  *
   3  * Module Name: exconvrt - Object conversion routines
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2008, 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 <acpi/acinterp.h>
  46 #include <acpi/amlcode.h>
  47
  48 #define _COMPONENT          ACPI_EXECUTER
  49 ACPI_MODULE_NAME("exconvrt")
  50
  51 /* Local prototypes */
  52 static u32
  53 acpi_ex_convert_to_ascii(acpi_integer integer,
  54                          u16 base, u8 * string, u8 max_length);
  55
  56 /*******************************************************************************
  57  *
  58  * FUNCTION:    acpi_ex_convert_to_integer
  59  *
  60  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
  61  *                                Integer, Buffer, or String
  62  *              result_desc     - Where the new Integer object is returned
  63  *              Flags           - Used for string conversion
  64  *
  65  * RETURN:      Status
  66  *
  67  * DESCRIPTION: Convert an ACPI Object to an integer.
  68  *
  69  ******************************************************************************/
  70
  71 acpi_status
  72 acpi_ex_convert_to_integer(union acpi_operand_object *obj_desc,
  73                            union acpi_operand_object **result_desc, u32 flags)
  74 {
  75         union acpi_operand_object *return_desc;
  76         u8 *pointer;
  77         acpi_integer result;
  78         u32 i;
  79         u32 count;
  80         acpi_status status;
  81
  82         ACPI_FUNCTION_TRACE_PTR(ex_convert_to_integer, obj_desc);
  83
  84         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
  85         case ACPI_TYPE_INTEGER:
  86
  87                 /* No conversion necessary */
  88
  89                 *result_desc = obj_desc;
  90                 return_ACPI_STATUS(AE_OK);
  91
  92         case ACPI_TYPE_BUFFER:
  93         case ACPI_TYPE_STRING:
  94
  95                 /* Note: Takes advantage of common buffer/string fields */
  96
  97                 pointer = obj_desc->buffer.pointer;
  98                 count = obj_desc->buffer.length;
  99                 break;
 100
 101         default:
 102                 return_ACPI_STATUS(AE_TYPE);
 103         }
 104
 105         /*
 106          * Convert the buffer/string to an integer. Note that both buffers and
 107          * strings are treated as raw data - we don't convert ascii to hex for
 108          * strings.
 109          *
 110          * There are two terminating conditions for the loop:
 111          * 1) The size of an integer has been reached, or
 112          * 2) The end of the buffer or string has been reached
 113          */
 114         result = 0;
 115
 116         /* String conversion is different than Buffer conversion */
 117
 118         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
 119         case ACPI_TYPE_STRING:
 120
 121                 /*
 122                  * Convert string to an integer - for most cases, the string must be
 123                  * hexadecimal as per the ACPI specification. The only exception (as
 124                  * of ACPI 3.0) is that the to_integer() operator allows both decimal
 125                  * and hexadecimal strings (hex prefixed with "0x").
 126                  */
 127                 status = acpi_ut_strtoul64((char *)pointer, flags, &result);
 128                 if (ACPI_FAILURE(status)) {
 129                         return_ACPI_STATUS(status);
 130                 }
 131                 break;
 132
 133         case ACPI_TYPE_BUFFER:
 134
 135                 /* Check for zero-length buffer */
 136
 137                 if (!count) {
 138                         return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
 139                 }
 140
 141                 /* Transfer no more than an integer's worth of data */
 142
 143                 if (count > acpi_gbl_integer_byte_width) {
 144                         count = acpi_gbl_integer_byte_width;
 145                 }
 146
 147                 /*
 148                  * Convert buffer to an integer - we simply grab enough raw data
 149                  * from the buffer to fill an integer
 150                  */
 151                 for (i = 0; i < count; i++) {
 152                         /*
 153                          * Get next byte and shift it into the Result.
 154                          * Little endian is used, meaning that the first byte of the buffer
 155                          * is the LSB of the integer
 156                          */
 157                         result |= (((acpi_integer) pointer[i]) << (i * 8));
 158                 }
 159                 break;
 160
 161         default:
 162
 163                 /* No other types can get here */
 164                 break;
 165         }
 166
 167         /* Create a new integer */
 168
 169         return_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
 170         if (!return_desc) {
 171                 return_ACPI_STATUS(AE_NO_MEMORY);
 172         }
 173
 174         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Converted value: %8.8X%8.8X\n",
 175                           ACPI_FORMAT_UINT64(result)));
 176
 177         /* Save the Result */
 178
 179         return_desc->integer.value = result;
 180         acpi_ex_truncate_for32bit_table(return_desc);
 181         *result_desc = return_desc;
 182         return_ACPI_STATUS(AE_OK);
 183 }
 184
 185 /*******************************************************************************
 186  *
 187  * FUNCTION:    acpi_ex_convert_to_buffer
 188  *
 189  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
 190  *                                Integer, Buffer, or String
 191  *              result_desc     - Where the new buffer object is returned
 192  *
 193  * RETURN:      Status
 194  *
 195  * DESCRIPTION: Convert an ACPI Object to a Buffer
 196  *
 197  ******************************************************************************/
 198
 199 acpi_status
 200 acpi_ex_convert_to_buffer(union acpi_operand_object *obj_desc,
 201                           union acpi_operand_object **result_desc)
 202 {
 203         union acpi_operand_object *return_desc;
 204         u8 *new_buf;
 205
 206         ACPI_FUNCTION_TRACE_PTR(ex_convert_to_buffer, obj_desc);
 207
 208         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
 209         case ACPI_TYPE_BUFFER:
 210
 211                 /* No conversion necessary */
 212
 213                 *result_desc = obj_desc;
 214                 return_ACPI_STATUS(AE_OK);
 215
 216         case ACPI_TYPE_INTEGER:
 217
 218                 /*
 219                  * Create a new Buffer object.
 220                  * Need enough space for one integer
 221                  */
 222                 return_desc =
 223                     acpi_ut_create_buffer_object(acpi_gbl_integer_byte_width);
 224                 if (!return_desc) {
 225                         return_ACPI_STATUS(AE_NO_MEMORY);
 226                 }
 227
 228                 /* Copy the integer to the buffer, LSB first */
 229
 230                 new_buf = return_desc->buffer.pointer;
 231                 ACPI_MEMCPY(new_buf,
 232                             &obj_desc->integer.value,
 233                             acpi_gbl_integer_byte_width);
 234                 break;
 235
 236         case ACPI_TYPE_STRING:
 237
 238                 /*
 239                  * Create a new Buffer object
 240                  * Size will be the string length
 241                  *
 242                  * NOTE: Add one to the string length to include the null terminator.
 243                  * The ACPI spec is unclear on this subject, but there is existing
 244                  * ASL/AML code that depends on the null being transferred to the new
 245                  * buffer.
 246                  */
 247                 return_desc = acpi_ut_create_buffer_object((acpi_size)
 248                                                            obj_desc->string.
 249                                                            length + 1);
 250                 if (!return_desc) {
 251                         return_ACPI_STATUS(AE_NO_MEMORY);
 252                 }
 253
 254                 /* Copy the string to the buffer */
 255
 256                 new_buf = return_desc->buffer.pointer;
 257                 ACPI_STRNCPY((char *)new_buf, (char *)obj_desc->string.pointer,
 258                              obj_desc->string.length);
 259                 break;
 260
 261         default:
 262                 return_ACPI_STATUS(AE_TYPE);
 263         }
 264
 265         /* Mark buffer initialized */
 266
 267         return_desc->common.flags |= AOPOBJ_DATA_VALID;
 268         *result_desc = return_desc;
 269         return_ACPI_STATUS(AE_OK);
 270 }
 271
 272 /*******************************************************************************
 273  *
 274  * FUNCTION:    acpi_ex_convert_to_ascii
 275  *
 276  * PARAMETERS:  Integer         - Value to be converted
 277  *              Base            - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
 278  *              String          - Where the string is returned
 279  *              data_width      - Size of data item to be converted, in bytes
 280  *
 281  * RETURN:      Actual string length
 282  *
 283  * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
 284  *
 285  ******************************************************************************/
 286
 287 static u32
 288 acpi_ex_convert_to_ascii(acpi_integer integer,
 289                          u16 base, u8 * string, u8 data_width)
 290 {
 291         acpi_integer digit;
 292         u32 i;
 293         u32 j;
 294         u32 k = 0;
 295         u32 hex_length;
 296         u32 decimal_length;
 297         u32 remainder;
 298         u8 supress_zeros;
 299
 300         ACPI_FUNCTION_ENTRY();
 301
 302         switch (base) {
 303         case 10:
 304
 305                 /* Setup max length for the decimal number */
 306
 307                 switch (data_width) {
 308                 case 1:
 309                         decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
 310                         break;
 311
 312                 case 4:
 313                         decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
 314                         break;
 315
 316                 case 8:
 317                 default:
 318                         decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
 319                         break;
 320                 }
 321
 322                 supress_zeros = TRUE;   /* No leading zeros */
 323                 remainder = 0;
 324
 325                 for (i = decimal_length; i > 0; i--) {
 326
 327                         /* Divide by nth factor of 10 */
 328
 329                         digit = integer;
 330                         for (j = 0; j < i; j++) {
 331                                 (void)acpi_ut_short_divide(digit, 10, &digit,
 332                                                            &remainder);
 333                         }
 334
 335                         /* Handle leading zeros */
 336
 337                         if (remainder != 0) {
 338                                 supress_zeros = FALSE;
 339                         }
 340
 341                         if (!supress_zeros) {
 342                                 string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
 343                                 k++;
 344                         }
 345                 }
 346                 break;
 347
 348         case 16:
 349
 350                 /* hex_length: 2 ascii hex chars per data byte */
 351
 352                 hex_length = ACPI_MUL_2(data_width);
 353                 for (i = 0, j = (hex_length - 1); i < hex_length; i++, j--) {
 354
 355                         /* Get one hex digit, most significant digits first */
 356
 357                         string[k] =
 358                             (u8) acpi_ut_hex_to_ascii_char(integer,
 359                                                            ACPI_MUL_4(j));
 360                         k++;
 361                 }
 362                 break;
 363
 364         default:
 365                 return (0);
 366         }
 367
 368         /*
 369          * Since leading zeros are suppressed, we must check for the case where
 370          * the integer equals 0
 371          *
 372          * Finally, null terminate the string and return the length
 373          */
 374         if (!k) {
 375                 string[0] = ACPI_ASCII_ZERO;
 376                 k = 1;
 377         }
 378
 379         string[k] = 0;
 380         return ((u32) k);
 381 }
 382
 383 /*******************************************************************************
 384  *
 385  * FUNCTION:    acpi_ex_convert_to_string
 386  *
 387  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
 388  *                                Integer, Buffer, or String
 389  *              result_desc     - Where the string object is returned
 390  *              Type            - String flags (base and conversion type)
 391  *
 392  * RETURN:      Status
 393  *
 394  * DESCRIPTION: Convert an ACPI Object to a string
 395  *
 396  ******************************************************************************/
 397
 398 acpi_status
 399 acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,
 400                           union acpi_operand_object ** result_desc, u32 type)
 401 {
 402         union acpi_operand_object *return_desc;
 403         u8 *new_buf;
 404         u32 i;
 405         u32 string_length = 0;
 406         u16 base = 16;
 407         u8 separator = ',';
 408
 409         ACPI_FUNCTION_TRACE_PTR(ex_convert_to_string, obj_desc);
 410
 411         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
 412         case ACPI_TYPE_STRING:
 413
 414                 /* No conversion necessary */
 415
 416                 *result_desc = obj_desc;
 417                 return_ACPI_STATUS(AE_OK);
 418
 419         case ACPI_TYPE_INTEGER:
 420
 421                 switch (type) {
 422                 case ACPI_EXPLICIT_CONVERT_DECIMAL:
 423
 424                         /* Make room for maximum decimal number */
 425
 426                         string_length = ACPI_MAX_DECIMAL_DIGITS;
 427                         base = 10;
 428                         break;
 429
 430                 default:
 431
 432                         /* Two hex string characters for each integer byte */
 433
 434                         string_length = ACPI_MUL_2(acpi_gbl_integer_byte_width);
 435                         break;
 436                 }
 437
 438                 /*
 439                  * Create a new String
 440                  * Need enough space for one ASCII integer (plus null terminator)
 441                  */
 442                 return_desc =
 443                     acpi_ut_create_string_object((acpi_size) string_length);
 444                 if (!return_desc) {
 445                         return_ACPI_STATUS(AE_NO_MEMORY);
 446                 }
 447
 448                 new_buf = return_desc->buffer.pointer;
 449
 450                 /* Convert integer to string */
 451
 452                 string_length =
 453                     acpi_ex_convert_to_ascii(obj_desc->integer.value, base,
 454                                              new_buf,
 455                                              acpi_gbl_integer_byte_width);
 456
 457                 /* Null terminate at the correct place */
 458
 459                 return_desc->string.length = string_length;
 460                 new_buf[string_length] = 0;
 461                 break;
 462
 463         case ACPI_TYPE_BUFFER:
 464
 465                 /* Setup string length, base, and separator */
 466
 467                 switch (type) {
 468                 case ACPI_EXPLICIT_CONVERT_DECIMAL:     /* Used by to_decimal_string */
 469                         /*
 470                          * From ACPI: "If Data is a buffer, it is converted to a string of
 471                          * decimal values separated by commas."
 472                          */
 473                         base = 10;
 474
 475                         /*
 476                          * Calculate the final string length. Individual string values
 477                          * are variable length (include separator for each)
 478                          */
 479                         for (i = 0; i < obj_desc->buffer.length; i++) {
 480                                 if (obj_desc->buffer.pointer[i] >= 100) {
 481                                         string_length += 4;
 482                                 } else if (obj_desc->buffer.pointer[i] >= 10) {
 483                                         string_length += 3;
 484                                 } else {
 485                                         string_length += 2;
 486                                 }
 487                         }
 488                         break;
 489
 490                 case ACPI_IMPLICIT_CONVERT_HEX:
 491                         /*
 492                          * From the ACPI spec:
 493                          *"The entire contents of the buffer are converted to a string of
 494                          * two-character hexadecimal numbers, each separated by a space."
 495                          */
 496                         separator = ' ';
 497                         string_length = (obj_desc->buffer.length * 3);
 498                         break;
 499
 500                 case ACPI_EXPLICIT_CONVERT_HEX: /* Used by to_hex_string */
 501                         /*
 502                          * From ACPI: "If Data is a buffer, it is converted to a string of
 503                          * hexadecimal values separated by commas."
 504                          */
 505                         string_length = (obj_desc->buffer.length * 3);
 506                         break;
 507
 508                 default:
 509                         return_ACPI_STATUS(AE_BAD_PARAMETER);
 510                 }
 511
 512                 /*
 513                  * Create a new string object and string buffer
 514                  * (-1 because of extra separator included in string_length from above)
 515                  * Allow creation of zero-length strings from zero-length buffers.
 516                  */
 517                 if (string_length) {
 518                         string_length--;
 519                 }
 520
 521                 return_desc = acpi_ut_create_string_object((acpi_size)
 522                                                            string_length);
 523                 if (!return_desc) {
 524                         return_ACPI_STATUS(AE_NO_MEMORY);
 525                 }
 526
 527                 new_buf = return_desc->buffer.pointer;
 528
 529                 /*
 530                  * Convert buffer bytes to hex or decimal values
 531                  * (separated by commas or spaces)
 532                  */
 533                 for (i = 0; i < obj_desc->buffer.length; i++) {
 534                         new_buf += acpi_ex_convert_to_ascii((acpi_integer)
 535                                                             obj_desc->buffer.
 536                                                             pointer[i], base,
 537                                                             new_buf, 1);
 538                         *new_buf++ = separator; /* each separated by a comma or space */
 539                 }
 540
 541                 /*
 542                  * Null terminate the string
 543                  * (overwrites final comma/space from above)
 544                  */
 545                 if (obj_desc->buffer.length) {
 546                         new_buf--;
 547                 }
 548                 *new_buf = 0;
 549                 break;
 550
 551         default:
 552                 return_ACPI_STATUS(AE_TYPE);
 553         }
 554
 555         *result_desc = return_desc;
 556         return_ACPI_STATUS(AE_OK);
 557 }
 558
 559 /*******************************************************************************
 560  *
 561  * FUNCTION:    acpi_ex_convert_to_target_type
 562  *
 563  * PARAMETERS:  destination_type    - Current type of the destination
 564  *              source_desc         - Source object to be converted.
 565  *              result_desc         - Where the converted object is returned
 566  *              walk_state          - Current method state
 567  *
 568  * RETURN:      Status
 569  *
 570  * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
 571  *
 572  ******************************************************************************/
 573
 574 acpi_status
 575 acpi_ex_convert_to_target_type(acpi_object_type destination_type,
 576                                union acpi_operand_object *source_desc,
 577                                union acpi_operand_object **result_desc,
 578                                struct acpi_walk_state *walk_state)
 579 {
 580         acpi_status status = AE_OK;
 581
 582         ACPI_FUNCTION_TRACE(ex_convert_to_target_type);
 583
 584         /* Default behavior */
 585
 586         *result_desc = source_desc;
 587
 588         /*
 589          * If required by the target,
 590          * perform implicit conversion on the source before we store it.
 591          */
 592         switch (GET_CURRENT_ARG_TYPE(walk_state->op_info->runtime_args)) {
 593         case ARGI_SIMPLE_TARGET:
 594         case ARGI_FIXED_TARGET:
 595         case ARGI_INTEGER_REF:  /* Handles Increment, Decrement cases */
 596
 597                 switch (destination_type) {
 598                 case ACPI_TYPE_LOCAL_REGION_FIELD:
 599                         /*
 600                          * Named field can always handle conversions
 601                          */
 602                         break;
 603
 604                 default:
 605                         /* No conversion allowed for these types */
 606
 607                         if (destination_type !=
 608                             ACPI_GET_OBJECT_TYPE(source_desc)) {
 609                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 610                                                   "Explicit operator, will store (%s) over existing type (%s)\n",
 611                                                   acpi_ut_get_object_type_name
 612                                                   (source_desc),
 613                                                   acpi_ut_get_type_name
 614                                                   (destination_type)));
 615                                 status = AE_TYPE;
 616                         }
 617                 }
 618                 break;
 619
 620         case ARGI_TARGETREF:
 621
 622                 switch (destination_type) {
 623                 case ACPI_TYPE_INTEGER:
 624                 case ACPI_TYPE_BUFFER_FIELD:
 625                 case ACPI_TYPE_LOCAL_BANK_FIELD:
 626                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
 627                         /*
 628                          * These types require an Integer operand. We can convert
 629                          * a Buffer or a String to an Integer if necessary.
 630                          */
 631                         status =
 632                             acpi_ex_convert_to_integer(source_desc, result_desc,
 633                                                        16);
 634                         break;
 635
 636                 case ACPI_TYPE_STRING:
 637                         /*
 638                          * The operand must be a String. We can convert an
 639                          * Integer or Buffer if necessary
 640                          */
 641                         status =
 642                             acpi_ex_convert_to_string(source_desc, result_desc,
 643                                                       ACPI_IMPLICIT_CONVERT_HEX);
 644                         break;
 645
 646                 case ACPI_TYPE_BUFFER:
 647                         /*
 648                          * The operand must be a Buffer. We can convert an
 649                          * Integer or String if necessary
 650                          */
 651                         status =
 652                             acpi_ex_convert_to_buffer(source_desc, result_desc);
 653                         break;
 654
 655                 default:
 656                         ACPI_ERROR((AE_INFO,
 657                                     "Bad destination type during conversion: %X",
 658                                     destination_type));
 659                         status = AE_AML_INTERNAL;
 660                         break;
 661                 }
 662                 break;
 663
 664         case ARGI_REFERENCE:
 665                 /*
 666                  * create_xxxx_field cases - we are storing the field object into the name
 667                  */
 668                 break;
 669
 670         default:
 671                 ACPI_ERROR((AE_INFO,
 672                             "Unknown Target type ID 0x%X AmlOpcode %X DestType %s",
 673                             GET_CURRENT_ARG_TYPE(walk_state->op_info->
 674                                                  runtime_args),
 675                             walk_state->opcode,
 676                             acpi_ut_get_type_name(destination_type)));
 677                 status = AE_AML_INTERNAL;
 678         }
 679
 680         /*
 681          * Source-to-Target conversion semantics:
 682          *
 683          * If conversion to the target type cannot be performed, then simply
 684          * overwrite the target with the new object and type.
 685          */
 686         if (status == AE_TYPE) {
 687                 status = AE_OK;
 688         }
 689
 690         return_ACPI_STATUS(status);
 691 }