drivers/acpi/acpica/exconvrt.c

   1 /******************************************************************************
   2  *
   3  * Module Name: exconvrt - Object conversion routines
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2011, 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(u64 integer, 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         u64 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 (obj_desc->common.type) {
  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 (obj_desc->common.type) {
 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 |= (((u64) 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_integer_object(result);
 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         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 (obj_desc->common.type) {
 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(u64 integer, u16 base, u8 *string, u8 data_width)
 288 {
 289         u64 digit;
 290         u32 i;
 291         u32 j;
 292         u32 k = 0;
 293         u32 hex_length;
 294         u32 decimal_length;
 295         u32 remainder;
 296         u8 supress_zeros;
 297
 298         ACPI_FUNCTION_ENTRY();
 299
 300         switch (base) {
 301         case 10:
 302
 303                 /* Setup max length for the decimal number */
 304
 305                 switch (data_width) {
 306                 case 1:
 307                         decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
 308                         break;
 309
 310                 case 4:
 311                         decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
 312                         break;
 313
 314                 case 8:
 315                 default:
 316                         decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
 317                         break;
 318                 }
 319
 320                 supress_zeros = TRUE;   /* No leading zeros */
 321                 remainder = 0;
 322
 323                 for (i = decimal_length; i > 0; i--) {
 324
 325                         /* Divide by nth factor of 10 */
 326
 327                         digit = integer;
 328                         for (j = 0; j < i; j++) {
 329                                 (void)acpi_ut_short_divide(digit, 10, &digit,
 330                                                            &remainder);
 331                         }
 332
 333                         /* Handle leading zeros */
 334
 335                         if (remainder != 0) {
 336                                 supress_zeros = FALSE;
 337                         }
 338
 339                         if (!supress_zeros) {
 340                                 string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
 341                                 k++;
 342                         }
 343                 }
 344                 break;
 345
 346         case 16:
 347
 348                 /* hex_length: 2 ascii hex chars per data byte */
 349
 350                 hex_length = ACPI_MUL_2(data_width);
 351                 for (i = 0, j = (hex_length - 1); i < hex_length; i++, j--) {
 352
 353                         /* Get one hex digit, most significant digits first */
 354
 355                         string[k] =
 356                             (u8) acpi_ut_hex_to_ascii_char(integer,
 357                                                            ACPI_MUL_4(j));
 358                         k++;
 359                 }
 360                 break;
 361
 362         default:
 363                 return (0);
 364         }
 365
 366         /*
 367          * Since leading zeros are suppressed, we must check for the case where
 368          * the integer equals 0
 369          *
 370          * Finally, null terminate the string and return the length
 371          */
 372         if (!k) {
 373                 string[0] = ACPI_ASCII_ZERO;
 374                 k = 1;
 375         }
 376
 377         string[k] = 0;
 378         return ((u32) k);
 379 }
 380
 381 /*******************************************************************************
 382  *
 383  * FUNCTION:    acpi_ex_convert_to_string
 384  *
 385  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
 386  *                                Integer, Buffer, or String
 387  *              result_desc     - Where the string object is returned
 388  *              Type            - String flags (base and conversion type)
 389  *
 390  * RETURN:      Status
 391  *
 392  * DESCRIPTION: Convert an ACPI Object to a string
 393  *
 394  ******************************************************************************/
 395
 396 acpi_status
 397 acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,
 398                           union acpi_operand_object ** result_desc, u32 type)
 399 {
 400         union acpi_operand_object *return_desc;
 401         u8 *new_buf;
 402         u32 i;
 403         u32 string_length = 0;
 404         u16 base = 16;
 405         u8 separator = ',';
 406
 407         ACPI_FUNCTION_TRACE_PTR(ex_convert_to_string, obj_desc);
 408
 409         switch (obj_desc->common.type) {
 410         case ACPI_TYPE_STRING:
 411
 412                 /* No conversion necessary */
 413
 414                 *result_desc = obj_desc;
 415                 return_ACPI_STATUS(AE_OK);
 416
 417         case ACPI_TYPE_INTEGER:
 418
 419                 switch (type) {
 420                 case ACPI_EXPLICIT_CONVERT_DECIMAL:
 421
 422                         /* Make room for maximum decimal number */
 423
 424                         string_length = ACPI_MAX_DECIMAL_DIGITS;
 425                         base = 10;
 426                         break;
 427
 428                 default:
 429
 430                         /* Two hex string characters for each integer byte */
 431
 432                         string_length = ACPI_MUL_2(acpi_gbl_integer_byte_width);
 433                         break;
 434                 }
 435
 436                 /*
 437                  * Create a new String
 438                  * Need enough space for one ASCII integer (plus null terminator)
 439                  */
 440                 return_desc =
 441                     acpi_ut_create_string_object((acpi_size) string_length);
 442                 if (!return_desc) {
 443                         return_ACPI_STATUS(AE_NO_MEMORY);
 444                 }
 445
 446                 new_buf = return_desc->buffer.pointer;
 447
 448                 /* Convert integer to string */
 449
 450                 string_length =
 451                     acpi_ex_convert_to_ascii(obj_desc->integer.value, base,
 452                                              new_buf,
 453                                              acpi_gbl_integer_byte_width);
 454
 455                 /* Null terminate at the correct place */
 456
 457                 return_desc->string.length = string_length;
 458                 new_buf[string_length] = 0;
 459                 break;
 460
 461         case ACPI_TYPE_BUFFER:
 462
 463                 /* Setup string length, base, and separator */
 464
 465                 switch (type) {
 466                 case ACPI_EXPLICIT_CONVERT_DECIMAL:     /* Used by to_decimal_string */
 467                         /*
 468                          * From ACPI: "If Data is a buffer, it is converted to a string of
 469                          * decimal values separated by commas."
 470                          */
 471                         base = 10;
 472
 473                         /*
 474                          * Calculate the final string length. Individual string values
 475                          * are variable length (include separator for each)
 476                          */
 477                         for (i = 0; i < obj_desc->buffer.length; i++) {
 478                                 if (obj_desc->buffer.pointer[i] >= 100) {
 479                                         string_length += 4;
 480                                 } else if (obj_desc->buffer.pointer[i] >= 10) {
 481                                         string_length += 3;
 482                                 } else {
 483                                         string_length += 2;
 484                                 }
 485                         }
 486                         break;
 487
 488                 case ACPI_IMPLICIT_CONVERT_HEX:
 489                         /*
 490                          * From the ACPI spec:
 491                          *"The entire contents of the buffer are converted to a string of
 492                          * two-character hexadecimal numbers, each separated by a space."
 493                          */
 494                         separator = ' ';
 495                         string_length = (obj_desc->buffer.length * 3);
 496                         break;
 497
 498                 case ACPI_EXPLICIT_CONVERT_HEX: /* Used by to_hex_string */
 499                         /*
 500                          * From ACPI: "If Data is a buffer, it is converted to a string of
 501                          * hexadecimal values separated by commas."
 502                          */
 503                         string_length = (obj_desc->buffer.length * 3);
 504                         break;
 505
 506                 default:
 507                         return_ACPI_STATUS(AE_BAD_PARAMETER);
 508                 }
 509
 510                 /*
 511                  * Create a new string object and string buffer
 512                  * (-1 because of extra separator included in string_length from above)
 513                  * Allow creation of zero-length strings from zero-length buffers.
 514                  */
 515                 if (string_length) {
 516                         string_length--;
 517                 }
 518
 519                 return_desc = acpi_ut_create_string_object((acpi_size)
 520                                                            string_length);
 521                 if (!return_desc) {
 522                         return_ACPI_STATUS(AE_NO_MEMORY);
 523                 }
 524
 525                 new_buf = return_desc->buffer.pointer;
 526
 527                 /*
 528                  * Convert buffer bytes to hex or decimal values
 529                  * (separated by commas or spaces)
 530                  */
 531                 for (i = 0; i < obj_desc->buffer.length; i++) {
 532                         new_buf += acpi_ex_convert_to_ascii((u64) obj_desc->
 533                                                             buffer.pointer[i],
 534                                                             base, new_buf, 1);
 535                         *new_buf++ = separator; /* each separated by a comma or space */
 536                 }
 537
 538                 /*
 539                  * Null terminate the string
 540                  * (overwrites final comma/space from above)
 541                  */
 542                 if (obj_desc->buffer.length) {
 543                         new_buf--;
 544                 }
 545                 *new_buf = 0;
 546                 break;
 547
 548         default:
 549                 return_ACPI_STATUS(AE_TYPE);
 550         }
 551
 552         *result_desc = return_desc;
 553         return_ACPI_STATUS(AE_OK);
 554 }
 555
 556 /*******************************************************************************
 557  *
 558  * FUNCTION:    acpi_ex_convert_to_target_type
 559  *
 560  * PARAMETERS:  destination_type    - Current type of the destination
 561  *              source_desc         - Source object to be converted.
 562  *              result_desc         - Where the converted object is returned
 563  *              walk_state          - Current method state
 564  *
 565  * RETURN:      Status
 566  *
 567  * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
 568  *
 569  ******************************************************************************/
 570
 571 acpi_status
 572 acpi_ex_convert_to_target_type(acpi_object_type destination_type,
 573                                union acpi_operand_object *source_desc,
 574                                union acpi_operand_object **result_desc,
 575                                struct acpi_walk_state *walk_state)
 576 {
 577         acpi_status status = AE_OK;
 578
 579         ACPI_FUNCTION_TRACE(ex_convert_to_target_type);
 580
 581         /* Default behavior */
 582
 583         *result_desc = source_desc;
 584
 585         /*
 586          * If required by the target,
 587          * perform implicit conversion on the source before we store it.
 588          */
 589         switch (GET_CURRENT_ARG_TYPE(walk_state->op_info->runtime_args)) {
 590         case ARGI_SIMPLE_TARGET:
 591         case ARGI_FIXED_TARGET:
 592         case ARGI_INTEGER_REF:  /* Handles Increment, Decrement cases */
 593
 594                 switch (destination_type) {
 595                 case ACPI_TYPE_LOCAL_REGION_FIELD:
 596                         /*
 597                          * Named field can always handle conversions
 598                          */
 599                         break;
 600
 601                 default:
 602                         /* No conversion allowed for these types */
 603
 604                         if (destination_type != source_desc->common.type) {
 605                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 606                                                   "Explicit operator, will store (%s) over existing type (%s)\n",
 607                                                   acpi_ut_get_object_type_name
 608                                                   (source_desc),
 609                                                   acpi_ut_get_type_name
 610                                                   (destination_type)));
 611                                 status = AE_TYPE;
 612                         }
 613                 }
 614                 break;
 615
 616         case ARGI_TARGETREF:
 617
 618                 switch (destination_type) {
 619                 case ACPI_TYPE_INTEGER:
 620                 case ACPI_TYPE_BUFFER_FIELD:
 621                 case ACPI_TYPE_LOCAL_BANK_FIELD:
 622                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
 623                         /*
 624                          * These types require an Integer operand. We can convert
 625                          * a Buffer or a String to an Integer if necessary.
 626                          */
 627                         status =
 628                             acpi_ex_convert_to_integer(source_desc, result_desc,
 629                                                        16);
 630                         break;
 631
 632                 case ACPI_TYPE_STRING:
 633                         /*
 634                          * The operand must be a String. We can convert an
 635                          * Integer or Buffer if necessary
 636                          */
 637                         status =
 638                             acpi_ex_convert_to_string(source_desc, result_desc,
 639                                                       ACPI_IMPLICIT_CONVERT_HEX);
 640                         break;
 641
 642                 case ACPI_TYPE_BUFFER:
 643                         /*
 644                          * The operand must be a Buffer. We can convert an
 645                          * Integer or String if necessary
 646                          */
 647                         status =
 648                             acpi_ex_convert_to_buffer(source_desc, result_desc);
 649                         break;
 650
 651                 default:
 652                         ACPI_ERROR((AE_INFO,
 653                                     "Bad destination type during conversion: 0x%X",
 654                                     destination_type));
 655                         status = AE_AML_INTERNAL;
 656                         break;
 657                 }
 658                 break;
 659
 660         case ARGI_REFERENCE:
 661                 /*
 662                  * create_xxxx_field cases - we are storing the field object into the name
 663                  */
 664                 break;
 665
 666         default:
 667                 ACPI_ERROR((AE_INFO,
 668                             "Unknown Target type ID 0x%X AmlOpcode 0x%X DestType %s",
 669                             GET_CURRENT_ARG_TYPE(walk_state->op_info->
 670                                                  runtime_args),
 671                             walk_state->opcode,
 672                             acpi_ut_get_type_name(destination_type)));
 673                 status = AE_AML_INTERNAL;
 674         }
 675
 676         /*
 677          * Source-to-Target conversion semantics:
 678          *
 679          * If conversion to the target type cannot be performed, then simply
 680          * overwrite the target with the new object and type.
 681          */
 682         if (status == AE_TYPE) {
 683                 status = AE_OK;
 684         }
 685
 686         return_ACPI_STATUS(status);
 687 }