git.oblomov.eu Git - linux-2.6/blob - drivers/acpi/acpica/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 "accommon.h"
  46 #include "acinterp.h"
  47 #include "amlcode.h"
  48
  49 #define _COMPONENT          ACPI_EXECUTER
  50 ACPI_MODULE_NAME("exconvrt")
  51
  52 /* Local prototypes */
  53 static u32
  54 acpi_ex_convert_to_ascii(acpi_integer integer,
  55                          u16 base, u8 * string, u8 max_length);
  56
  57 /*******************************************************************************
  58  *
  59  * FUNCTION:    acpi_ex_convert_to_integer
  60  *
  61  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
  62  *                                Integer, Buffer, or String
  63  *              result_desc     - Where the new Integer object is returned
  64  *              Flags           - Used for string conversion
  65  *
  66  * RETURN:      Status
  67  *
  68  * DESCRIPTION: Convert an ACPI Object to an integer.
  69  *
  70  ******************************************************************************/
  71
  72 acpi_status
  73 acpi_ex_convert_to_integer(union acpi_operand_object *obj_desc,
  74                            union acpi_operand_object **result_desc, u32 flags)
  75 {
  76         union acpi_operand_object *return_desc;
  77         u8 *pointer;
  78         acpi_integer result;
  79         u32 i;
  80         u32 count;
  81         acpi_status status;
  82
  83         ACPI_FUNCTION_TRACE_PTR(ex_convert_to_integer, obj_desc);
  84
  85         switch (obj_desc->common.type) {
  86         case ACPI_TYPE_INTEGER:
  87
  88                 /* No conversion necessary */
  89
  90                 *result_desc = obj_desc;
  91                 return_ACPI_STATUS(AE_OK);
  92
  93         case ACPI_TYPE_BUFFER:
  94         case ACPI_TYPE_STRING:
  95
  96                 /* Note: Takes advantage of common buffer/string fields */
  97
  98                 pointer = obj_desc->buffer.pointer;
  99                 count = obj_desc->buffer.length;
 100                 break;
 101
 102         default:
 103                 return_ACPI_STATUS(AE_TYPE);
 104         }
 105
 106         /*
 107          * Convert the buffer/string to an integer. Note that both buffers and
 108          * strings are treated as raw data - we don't convert ascii to hex for
 109          * strings.
 110          *
 111          * There are two terminating conditions for the loop:
 112          * 1) The size of an integer has been reached, or
 113          * 2) The end of the buffer or string has been reached
 114          */
 115         result = 0;
 116
 117         /* String conversion is different than Buffer conversion */
 118
 119         switch (obj_desc->common.type) {
 120         case ACPI_TYPE_STRING:
 121
 122                 /*
 123                  * Convert string to an integer - for most cases, the string must be
 124                  * hexadecimal as per the ACPI specification. The only exception (as
 125                  * of ACPI 3.0) is that the to_integer() operator allows both decimal
 126                  * and hexadecimal strings (hex prefixed with "0x").
 127                  */
 128                 status = acpi_ut_strtoul64((char *)pointer, flags, &result);
 129                 if (ACPI_FAILURE(status)) {
 130                         return_ACPI_STATUS(status);
 131                 }
 132                 break;
 133
 134         case ACPI_TYPE_BUFFER:
 135
 136                 /* Check for zero-length buffer */
 137
 138                 if (!count) {
 139                         return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
 140                 }
 141
 142                 /* Transfer no more than an integer's worth of data */
 143
 144                 if (count > acpi_gbl_integer_byte_width) {
 145                         count = acpi_gbl_integer_byte_width;
 146                 }
 147
 148                 /*
 149                  * Convert buffer to an integer - we simply grab enough raw data
 150                  * from the buffer to fill an integer
 151                  */
 152                 for (i = 0; i < count; i++) {
 153                         /*
 154                          * Get next byte and shift it into the Result.
 155                          * Little endian is used, meaning that the first byte of the buffer
 156                          * is the LSB of the integer
 157                          */
 158                         result |= (((acpi_integer) pointer[i]) << (i * 8));
 159                 }
 160                 break;
 161
 162         default:
 163
 164                 /* No other types can get here */
 165                 break;
 166         }
 167
 168         /* Create a new integer */
 169
 170         return_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
 171         if (!return_desc) {
 172                 return_ACPI_STATUS(AE_NO_MEMORY);
 173         }
 174
 175         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Converted value: %8.8X%8.8X\n",
 176                           ACPI_FORMAT_UINT64(result)));
 177
 178         /* Save the Result */
 179
 180         return_desc->integer.value = result;
 181         acpi_ex_truncate_for32bit_table(return_desc);
 182         *result_desc = return_desc;
 183         return_ACPI_STATUS(AE_OK);
 184 }
 185
 186 /*******************************************************************************
 187  *
 188  * FUNCTION:    acpi_ex_convert_to_buffer
 189  *
 190  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
 191  *                                Integer, Buffer, or String
 192  *              result_desc     - Where the new buffer object is returned
 193  *
 194  * RETURN:      Status
 195  *
 196  * DESCRIPTION: Convert an ACPI Object to a Buffer
 197  *
 198  ******************************************************************************/
 199
 200 acpi_status
 201 acpi_ex_convert_to_buffer(union acpi_operand_object *obj_desc,
 202                           union acpi_operand_object **result_desc)
 203 {
 204         union acpi_operand_object *return_desc;
 205         u8 *new_buf;
 206
 207         ACPI_FUNCTION_TRACE_PTR(ex_convert_to_buffer, obj_desc);
 208
 209         switch (obj_desc->common.type) {
 210         case ACPI_TYPE_BUFFER:
 211
 212                 /* No conversion necessary */
 213
 214                 *result_desc = obj_desc;
 215                 return_ACPI_STATUS(AE_OK);
 216
 217         case ACPI_TYPE_INTEGER:
 218
 219                 /*
 220                  * Create a new Buffer object.
 221                  * Need enough space for one integer
 222                  */
 223                 return_desc =
 224                     acpi_ut_create_buffer_object(acpi_gbl_integer_byte_width);
 225                 if (!return_desc) {
 226                         return_ACPI_STATUS(AE_NO_MEMORY);
 227                 }
 228
 229                 /* Copy the integer to the buffer, LSB first */
 230
 231                 new_buf = return_desc->buffer.pointer;
 232                 ACPI_MEMCPY(new_buf,
 233                             &obj_desc->integer.value,
 234                             acpi_gbl_integer_byte_width);
 235                 break;
 236
 237         case ACPI_TYPE_STRING:
 238
 239                 /*
 240                  * Create a new Buffer object
 241                  * Size will be the string length
 242                  *
 243                  * NOTE: Add one to the string length to include the null terminator.
 244                  * The ACPI spec is unclear on this subject, but there is existing
 245                  * ASL/AML code that depends on the null being transferred to the new
 246                  * buffer.
 247                  */
 248                 return_desc = acpi_ut_create_buffer_object((acpi_size)
 249                                                            obj_desc->string.
 250                                                            length + 1);
 251                 if (!return_desc) {
 252                         return_ACPI_STATUS(AE_NO_MEMORY);
 253                 }
 254
 255                 /* Copy the string to the buffer */
 256
 257                 new_buf = return_desc->buffer.pointer;
 258                 ACPI_STRNCPY((char *)new_buf, (char *)obj_desc->string.pointer,
 259                              obj_desc->string.length);
 260                 break;
 261
 262         default:
 263                 return_ACPI_STATUS(AE_TYPE);
 264         }
 265
 266         /* Mark buffer initialized */
 267
 268         return_desc->common.flags |= AOPOBJ_DATA_VALID;
 269         *result_desc = return_desc;
 270         return_ACPI_STATUS(AE_OK);
 271 }
 272
 273 /*******************************************************************************
 274  *
 275  * FUNCTION:    acpi_ex_convert_to_ascii
 276  *
 277  * PARAMETERS:  Integer         - Value to be converted
 278  *              Base            - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
 279  *              String          - Where the string is returned
 280  *              data_width      - Size of data item to be converted, in bytes
 281  *
 282  * RETURN:      Actual string length
 283  *
 284  * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
 285  *
 286  ******************************************************************************/
 287
 288 static u32
 289 acpi_ex_convert_to_ascii(acpi_integer integer,
 290                          u16 base, u8 * string, u8 data_width)
 291 {
 292         acpi_integer digit;
 293         u32 i;
 294         u32 j;
 295         u32 k = 0;
 296         u32 hex_length;
 297         u32 decimal_length;
 298         u32 remainder;
 299         u8 supress_zeros;
 300
 301         ACPI_FUNCTION_ENTRY();
 302
 303         switch (base) {
 304         case 10:
 305
 306                 /* Setup max length for the decimal number */
 307
 308                 switch (data_width) {
 309                 case 1:
 310                         decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
 311                         break;
 312
 313                 case 4:
 314                         decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
 315                         break;
 316
 317                 case 8:
 318                 default:
 319                         decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
 320                         break;
 321                 }
 322
 323                 supress_zeros = TRUE;   /* No leading zeros */
 324                 remainder = 0;
 325
 326                 for (i = decimal_length; i > 0; i--) {
 327
 328                         /* Divide by nth factor of 10 */
 329
 330                         digit = integer;
 331                         for (j = 0; j < i; j++) {
 332                                 (void)acpi_ut_short_divide(digit, 10, &digit,
 333                                                            &remainder);
 334                         }
 335
 336                         /* Handle leading zeros */
 337
 338                         if (remainder != 0) {
 339                                 supress_zeros = FALSE;
 340                         }
 341
 342                         if (!supress_zeros) {
 343                                 string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
 344                                 k++;
 345                         }
 346                 }
 347                 break;
 348
 349         case 16:
 350
 351                 /* hex_length: 2 ascii hex chars per data byte */
 352
 353                 hex_length = ACPI_MUL_2(data_width);
 354                 for (i = 0, j = (hex_length - 1); i < hex_length; i++, j--) {
 355
 356                         /* Get one hex digit, most significant digits first */
 357
 358                         string[k] =
 359                             (u8) acpi_ut_hex_to_ascii_char(integer,
 360                                                            ACPI_MUL_4(j));
 361                         k++;
 362                 }
 363                 break;
 364
 365         default:
 366                 return (0);
 367         }
 368
 369         /*
 370          * Since leading zeros are suppressed, we must check for the case where
 371          * the integer equals 0
 372          *
 373          * Finally, null terminate the string and return the length
 374          */
 375         if (!k) {
 376                 string[0] = ACPI_ASCII_ZERO;
 377                 k = 1;
 378         }
 379
 380         string[k] = 0;
 381         return ((u32) k);
 382 }
 383
 384 /*******************************************************************************
 385  *
 386  * FUNCTION:    acpi_ex_convert_to_string
 387  *
 388  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
 389  *                                Integer, Buffer, or String
 390  *              result_desc     - Where the string object is returned
 391  *              Type            - String flags (base and conversion type)
 392  *
 393  * RETURN:      Status
 394  *
 395  * DESCRIPTION: Convert an ACPI Object to a string
 396  *
 397  ******************************************************************************/
 398
 399 acpi_status
 400 acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,
 401                           union acpi_operand_object ** result_desc, u32 type)
 402 {
 403         union acpi_operand_object *return_desc;
 404         u8 *new_buf;
 405         u32 i;
 406         u32 string_length = 0;
 407         u16 base = 16;
 408         u8 separator = ',';
 409
 410         ACPI_FUNCTION_TRACE_PTR(ex_convert_to_string, obj_desc);
 411
 412         switch (obj_desc->common.type) {
 413         case ACPI_TYPE_STRING:
 414
 415                 /* No conversion necessary */
 416
 417                 *result_desc = obj_desc;
 418                 return_ACPI_STATUS(AE_OK);
 419
 420         case ACPI_TYPE_INTEGER:
 421
 422                 switch (type) {
 423                 case ACPI_EXPLICIT_CONVERT_DECIMAL:
 424
 425                         /* Make room for maximum decimal number */
 426
 427                         string_length = ACPI_MAX_DECIMAL_DIGITS;
 428                         base = 10;
 429                         break;
 430
 431                 default:
 432
 433                         /* Two hex string characters for each integer byte */
 434
 435                         string_length = ACPI_MUL_2(acpi_gbl_integer_byte_width);
 436                         break;
 437                 }
 438
 439                 /*
 440                  * Create a new String
 441                  * Need enough space for one ASCII integer (plus null terminator)
 442                  */
 443                 return_desc =
 444                     acpi_ut_create_string_object((acpi_size) string_length);
 445                 if (!return_desc) {
 446                         return_ACPI_STATUS(AE_NO_MEMORY);
 447                 }
 448
 449                 new_buf = return_desc->buffer.pointer;
 450
 451                 /* Convert integer to string */
 452
 453                 string_length =
 454                     acpi_ex_convert_to_ascii(obj_desc->integer.value, base,
 455                                              new_buf,
 456                                              acpi_gbl_integer_byte_width);
 457
 458                 /* Null terminate at the correct place */
 459
 460                 return_desc->string.length = string_length;
 461                 new_buf[string_length] = 0;
 462                 break;
 463
 464         case ACPI_TYPE_BUFFER:
 465
 466                 /* Setup string length, base, and separator */
 467
 468                 switch (type) {
 469                 case ACPI_EXPLICIT_CONVERT_DECIMAL:     /* Used by to_decimal_string */
 470                         /*
 471                          * From ACPI: "If Data is a buffer, it is converted to a string of
 472                          * decimal values separated by commas."
 473                          */
 474                         base = 10;
 475
 476                         /*
 477                          * Calculate the final string length. Individual string values
 478                          * are variable length (include separator for each)
 479                          */
 480                         for (i = 0; i < obj_desc->buffer.length; i++) {
 481                                 if (obj_desc->buffer.pointer[i] >= 100) {
 482                                         string_length += 4;
 483                                 } else if (obj_desc->buffer.pointer[i] >= 10) {
 484                                         string_length += 3;
 485                                 } else {
 486                                         string_length += 2;
 487                                 }
 488                         }
 489                         break;
 490
 491                 case ACPI_IMPLICIT_CONVERT_HEX:
 492                         /*
 493                          * From the ACPI spec:
 494                          *"The entire contents of the buffer are converted to a string of
 495                          * two-character hexadecimal numbers, each separated by a space."
 496                          */
 497                         separator = ' ';
 498                         string_length = (obj_desc->buffer.length * 3);
 499                         break;
 500
 501                 case ACPI_EXPLICIT_CONVERT_HEX: /* Used by to_hex_string */
 502                         /*
 503                          * From ACPI: "If Data is a buffer, it is converted to a string of
 504                          * hexadecimal values separated by commas."
 505                          */
 506                         string_length = (obj_desc->buffer.length * 3);
 507                         break;
 508
 509                 default:
 510                         return_ACPI_STATUS(AE_BAD_PARAMETER);
 511                 }
 512
 513                 /*
 514                  * Create a new string object and string buffer
 515                  * (-1 because of extra separator included in string_length from above)
 516                  * Allow creation of zero-length strings from zero-length buffers.
 517                  */
 518                 if (string_length) {
 519                         string_length--;
 520                 }
 521
 522                 return_desc = acpi_ut_create_string_object((acpi_size)
 523                                                            string_length);
 524                 if (!return_desc) {
 525                         return_ACPI_STATUS(AE_NO_MEMORY);
 526                 }
 527
 528                 new_buf = return_desc->buffer.pointer;
 529
 530                 /*
 531                  * Convert buffer bytes to hex or decimal values
 532                  * (separated by commas or spaces)
 533                  */
 534                 for (i = 0; i < obj_desc->buffer.length; i++) {
 535                         new_buf += acpi_ex_convert_to_ascii((acpi_integer)
 536                                                             obj_desc->buffer.
 537                                                             pointer[i], base,
 538                                                             new_buf, 1);
 539                         *new_buf++ = separator; /* each separated by a comma or space */
 540                 }
 541
 542                 /*
 543                  * Null terminate the string
 544                  * (overwrites final comma/space from above)
 545                  */
 546                 if (obj_desc->buffer.length) {
 547                         new_buf--;
 548                 }
 549                 *new_buf = 0;
 550                 break;
 551
 552         default:
 553                 return_ACPI_STATUS(AE_TYPE);
 554         }
 555
 556         *result_desc = return_desc;
 557         return_ACPI_STATUS(AE_OK);
 558 }
 559
 560 /*******************************************************************************
 561  *
 562  * FUNCTION:    acpi_ex_convert_to_target_type
 563  *
 564  * PARAMETERS:  destination_type    - Current type of the destination
 565  *              source_desc         - Source object to be converted.
 566  *              result_desc         - Where the converted object is returned
 567  *              walk_state          - Current method state
 568  *
 569  * RETURN:      Status
 570  *
 571  * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
 572  *
 573  ******************************************************************************/
 574
 575 acpi_status
 576 acpi_ex_convert_to_target_type(acpi_object_type destination_type,
 577                                union acpi_operand_object *source_desc,
 578                                union acpi_operand_object **result_desc,
 579                                struct acpi_walk_state *walk_state)
 580 {
 581         acpi_status status = AE_OK;
 582
 583         ACPI_FUNCTION_TRACE(ex_convert_to_target_type);
 584
 585         /* Default behavior */
 586
 587         *result_desc = source_desc;
 588
 589         /*
 590          * If required by the target,
 591          * perform implicit conversion on the source before we store it.
 592          */
 593         switch (GET_CURRENT_ARG_TYPE(walk_state->op_info->runtime_args)) {
 594         case ARGI_SIMPLE_TARGET:
 595         case ARGI_FIXED_TARGET:
 596         case ARGI_INTEGER_REF:  /* Handles Increment, Decrement cases */
 597
 598                 switch (destination_type) {
 599                 case ACPI_TYPE_LOCAL_REGION_FIELD:
 600                         /*
 601                          * Named field can always handle conversions
 602                          */
 603                         break;
 604
 605                 default:
 606                         /* No conversion allowed for these types */
 607
 608                         if (destination_type != source_desc->common.type) {
 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 }