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