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

   1 /******************************************************************************
   2  *
   3  * Module Name: exfldio - Aml Field I/O
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2005, R. Byron Moore
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44
  45 #include <acpi/acpi.h>
  46 #include <acpi/acinterp.h>
  47 #include <acpi/amlcode.h>
  48 #include <acpi/acevents.h>
  49 #include <acpi/acdispat.h>
  50
  51
  52 #define _COMPONENT          ACPI_EXECUTER
  53          ACPI_MODULE_NAME    ("exfldio")
  54
  55 /* Local prototypes */
  56
  57 static acpi_status
  58 acpi_ex_field_datum_io (
  59         union acpi_operand_object       *obj_desc,
  60         u32                             field_datum_byte_offset,
  61         acpi_integer                    *value,
  62         u32                             read_write);
  63
  64 static u8
  65 acpi_ex_register_overflow (
  66         union acpi_operand_object       *obj_desc,
  67         acpi_integer                    value);
  68
  69 static acpi_status
  70 acpi_ex_setup_region (
  71         union acpi_operand_object       *obj_desc,
  72         u32                             field_datum_byte_offset);
  73
  74
  75 /*******************************************************************************
  76  *
  77  * FUNCTION:    acpi_ex_setup_region
  78  *
  79  * PARAMETERS:  obj_desc                - Field to be read or written
  80  *              field_datum_byte_offset - Byte offset of this datum within the
  81  *                                        parent field
  82  *
  83  * RETURN:      Status
  84  *
  85  * DESCRIPTION: Common processing for acpi_ex_extract_from_field and
  86  *              acpi_ex_insert_into_field. Initialize the Region if necessary and
  87  *              validate the request.
  88  *
  89  ******************************************************************************/
  90
  91 static acpi_status
  92 acpi_ex_setup_region (
  93         union acpi_operand_object       *obj_desc,
  94         u32                             field_datum_byte_offset)
  95 {
  96         acpi_status                     status = AE_OK;
  97         union acpi_operand_object       *rgn_desc;
  98
  99
 100         ACPI_FUNCTION_TRACE_U32 ("ex_setup_region", field_datum_byte_offset);
 101
 102
 103         rgn_desc = obj_desc->common_field.region_obj;
 104
 105         /* We must have a valid region */
 106
 107         if (ACPI_GET_OBJECT_TYPE (rgn_desc) != ACPI_TYPE_REGION) {
 108                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Needed Region, found type %X (%s)\n",
 109                         ACPI_GET_OBJECT_TYPE (rgn_desc),
 110                         acpi_ut_get_object_type_name (rgn_desc)));
 111
 112                 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
 113         }
 114
 115         /*
 116          * If the Region Address and Length have not been previously evaluated,
 117          * evaluate them now and save the results.
 118          */
 119         if (!(rgn_desc->common.flags & AOPOBJ_DATA_VALID)) {
 120                 status = acpi_ds_get_region_arguments (rgn_desc);
 121                 if (ACPI_FAILURE (status)) {
 122                         return_ACPI_STATUS (status);
 123                 }
 124         }
 125
 126         if (rgn_desc->region.space_id == ACPI_ADR_SPACE_SMBUS) {
 127                 /* SMBus has a non-linear address space */
 128
 129                 return_ACPI_STATUS (AE_OK);
 130         }
 131
 132 #ifdef ACPI_UNDER_DEVELOPMENT
 133         /*
 134          * If the Field access is any_acc, we can now compute the optimal
 135          * access (because we know know the length of the parent region)
 136          */
 137         if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 138                 if (ACPI_FAILURE (status)) {
 139                         return_ACPI_STATUS (status);
 140                 }
 141         }
 142 #endif
 143
 144         /*
 145          * Validate the request.  The entire request from the byte offset for a
 146          * length of one field datum (access width) must fit within the region.
 147          * (Region length is specified in bytes)
 148          */
 149         if (rgn_desc->region.length < (obj_desc->common_field.base_byte_offset +
 150                            field_datum_byte_offset +
 151                            obj_desc->common_field.access_byte_width)) {
 152                 if (acpi_gbl_enable_interpreter_slack) {
 153                         /*
 154                          * Slack mode only:  We will go ahead and allow access to this
 155                          * field if it is within the region length rounded up to the next
 156                          * access width boundary.
 157                          */
 158                         if (ACPI_ROUND_UP (rgn_desc->region.length,
 159                                            obj_desc->common_field.access_byte_width) >=
 160                                 (obj_desc->common_field.base_byte_offset +
 161                                  (acpi_native_uint) obj_desc->common_field.access_byte_width +
 162                                  field_datum_byte_offset)) {
 163                                 return_ACPI_STATUS (AE_OK);
 164                         }
 165                 }
 166
 167                 if (rgn_desc->region.length < obj_desc->common_field.access_byte_width) {
 168                         /*
 169                          * This is the case where the access_type (acc_word, etc.) is wider
 170                          * than the region itself.  For example, a region of length one
 171                          * byte, and a field with Dword access specified.
 172                          */
 173                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 174                                 "Field [%4.4s] access width (%d bytes) too large for region [%4.4s] (length %X)\n",
 175                                 acpi_ut_get_node_name (obj_desc->common_field.node),
 176                                 obj_desc->common_field.access_byte_width,
 177                                 acpi_ut_get_node_name (rgn_desc->region.node),
 178                                 rgn_desc->region.length));
 179                 }
 180
 181                 /*
 182                  * Offset rounded up to next multiple of field width
 183                  * exceeds region length, indicate an error
 184                  */
 185                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 186                         "Field [%4.4s] Base+Offset+Width %X+%X+%X is beyond end of region [%4.4s] (length %X)\n",
 187                         acpi_ut_get_node_name (obj_desc->common_field.node),
 188                         obj_desc->common_field.base_byte_offset,
 189                         field_datum_byte_offset, obj_desc->common_field.access_byte_width,
 190                         acpi_ut_get_node_name (rgn_desc->region.node),
 191                         rgn_desc->region.length));
 192
 193                 return_ACPI_STATUS (AE_AML_REGION_LIMIT);
 194         }
 195
 196         return_ACPI_STATUS (AE_OK);
 197 }
 198
 199
 200 /*******************************************************************************
 201  *
 202  * FUNCTION:    acpi_ex_access_region
 203  *
 204  * PARAMETERS:  obj_desc                - Field to be read
 205  *              field_datum_byte_offset - Byte offset of this datum within the
 206  *                                        parent field
 207  *              Value                   - Where to store value (must at least
 208  *                                        the size of acpi_integer)
 209  *              Function                - Read or Write flag plus other region-
 210  *                                        dependent flags
 211  *
 212  * RETURN:      Status
 213  *
 214  * DESCRIPTION: Read or Write a single field datum to an Operation Region.
 215  *
 216  ******************************************************************************/
 217
 218 acpi_status
 219 acpi_ex_access_region (
 220         union acpi_operand_object       *obj_desc,
 221         u32                             field_datum_byte_offset,
 222         acpi_integer                    *value,
 223         u32                             function)
 224 {
 225         acpi_status                     status;
 226         union acpi_operand_object       *rgn_desc;
 227         acpi_physical_address           address;
 228
 229
 230         ACPI_FUNCTION_TRACE ("ex_access_region");
 231
 232
 233         /*
 234          * Ensure that the region operands are fully evaluated and verify
 235          * the validity of the request
 236          */
 237         status = acpi_ex_setup_region (obj_desc, field_datum_byte_offset);
 238         if (ACPI_FAILURE (status)) {
 239                 return_ACPI_STATUS (status);
 240         }
 241
 242         /*
 243          * The physical address of this field datum is:
 244          *
 245          * 1) The base of the region, plus
 246          * 2) The base offset of the field, plus
 247          * 3) The current offset into the field
 248          */
 249         rgn_desc = obj_desc->common_field.region_obj;
 250         address = rgn_desc->region.address +
 251                          obj_desc->common_field.base_byte_offset +
 252                          field_datum_byte_offset;
 253
 254         if ((function & ACPI_IO_MASK) == ACPI_READ) {
 255                 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "[READ]"));
 256         }
 257         else {
 258                 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "[WRITE]"));
 259         }
 260
 261         ACPI_DEBUG_PRINT_RAW ((ACPI_DB_BFIELD,
 262                 " Region [%s:%X], Width %X, byte_base %X, Offset %X at %8.8X%8.8X\n",
 263                 acpi_ut_get_region_name (rgn_desc->region.space_id),
 264                 rgn_desc->region.space_id,
 265                 obj_desc->common_field.access_byte_width,
 266                 obj_desc->common_field.base_byte_offset,
 267                 field_datum_byte_offset,
 268                 ACPI_FORMAT_UINT64 (address)));
 269
 270         /* Invoke the appropriate address_space/op_region handler */
 271
 272         status = acpi_ev_address_space_dispatch (rgn_desc, function,
 273                          address,
 274                          ACPI_MUL_8 (obj_desc->common_field.access_byte_width), value);
 275
 276         if (ACPI_FAILURE (status)) {
 277                 if (status == AE_NOT_IMPLEMENTED) {
 278                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 279                                 "Region %s(%X) not implemented\n",
 280                                 acpi_ut_get_region_name (rgn_desc->region.space_id),
 281                                 rgn_desc->region.space_id));
 282                 }
 283                 else if (status == AE_NOT_EXIST) {
 284                         ACPI_REPORT_ERROR ((
 285                                 "Region %s(%X) has no handler\n",
 286                                 acpi_ut_get_region_name (rgn_desc->region.space_id),
 287                                 rgn_desc->region.space_id));
 288                 }
 289         }
 290
 291         return_ACPI_STATUS (status);
 292 }
 293
 294
 295 /*******************************************************************************
 296  *
 297  * FUNCTION:    acpi_ex_register_overflow
 298  *
 299  * PARAMETERS:  obj_desc                - Register(Field) to be written
 300  *              Value                   - Value to be stored
 301  *
 302  * RETURN:      TRUE if value overflows the field, FALSE otherwise
 303  *
 304  * DESCRIPTION: Check if a value is out of range of the field being written.
 305  *              Used to check if the values written to Index and Bank registers
 306  *              are out of range.  Normally, the value is simply truncated
 307  *              to fit the field, but this case is most likely a serious
 308  *              coding error in the ASL.
 309  *
 310  ******************************************************************************/
 311
 312 static u8
 313 acpi_ex_register_overflow (
 314         union acpi_operand_object       *obj_desc,
 315         acpi_integer                    value)
 316 {
 317
 318         if (obj_desc->common_field.bit_length >= ACPI_INTEGER_BIT_SIZE) {
 319                 /*
 320                  * The field is large enough to hold the maximum integer, so we can
 321                  * never overflow it.
 322                  */
 323                 return (FALSE);
 324         }
 325
 326         if (value >= ((acpi_integer) 1 << obj_desc->common_field.bit_length)) {
 327                 /*
 328                  * The Value is larger than the maximum value that can fit into
 329                  * the register.
 330                  */
 331                 return (TRUE);
 332         }
 333
 334         /* The Value will fit into the field with no truncation */
 335
 336         return (FALSE);
 337 }
 338
 339
 340 /*******************************************************************************
 341  *
 342  * FUNCTION:    acpi_ex_field_datum_io
 343  *
 344  * PARAMETERS:  obj_desc                - Field to be read
 345  *              field_datum_byte_offset - Byte offset of this datum within the
 346  *                                        parent field
 347  *              Value                   - Where to store value (must be 64 bits)
 348  *              read_write              - Read or Write flag
 349  *
 350  * RETURN:      Status
 351  *
 352  * DESCRIPTION: Read or Write a single datum of a field.  The field_type is
 353  *              demultiplexed here to handle the different types of fields
 354  *              (buffer_field, region_field, index_field, bank_field)
 355  *
 356  ******************************************************************************/
 357
 358 static acpi_status
 359 acpi_ex_field_datum_io (
 360         union acpi_operand_object       *obj_desc,
 361         u32                             field_datum_byte_offset,
 362         acpi_integer                    *value,
 363         u32                             read_write)
 364 {
 365         acpi_status                     status;
 366         acpi_integer                    local_value;
 367
 368
 369         ACPI_FUNCTION_TRACE_U32 ("ex_field_datum_io", field_datum_byte_offset);
 370
 371
 372         if (read_write == ACPI_READ) {
 373                 if (!value) {
 374                         local_value = 0;
 375
 376                         /* To support reads without saving return value */
 377                         value = &local_value;
 378                 }
 379
 380                 /* Clear the entire return buffer first, [Very Important!] */
 381
 382                 *value = 0;
 383         }
 384
 385         /*
 386          * The four types of fields are:
 387          *
 388          * buffer_field - Read/write from/to a Buffer
 389          * region_field - Read/write from/to a Operation Region.
 390          * bank_field  - Write to a Bank Register, then read/write from/to an
 391          *               operation_region
 392          * index_field - Write to an Index Register, then read/write from/to a
 393          *               Data Register
 394          */
 395         switch (ACPI_GET_OBJECT_TYPE (obj_desc)) {
 396         case ACPI_TYPE_BUFFER_FIELD:
 397                 /*
 398                  * If the buffer_field arguments have not been previously evaluated,
 399                  * evaluate them now and save the results.
 400                  */
 401                 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 402                         status = acpi_ds_get_buffer_field_arguments (obj_desc);
 403                         if (ACPI_FAILURE (status)) {
 404                                 return_ACPI_STATUS (status);
 405                         }
 406                 }
 407
 408                 if (read_write == ACPI_READ) {
 409                         /*
 410                          * Copy the data from the source buffer.
 411                          * Length is the field width in bytes.
 412                          */
 413                         ACPI_MEMCPY (value,
 414                                 (obj_desc->buffer_field.buffer_obj)->buffer.pointer +
 415                                         obj_desc->buffer_field.base_byte_offset +
 416                                         field_datum_byte_offset,
 417                                 obj_desc->common_field.access_byte_width);
 418                 }
 419                 else {
 420                         /*
 421                          * Copy the data to the target buffer.
 422                          * Length is the field width in bytes.
 423                          */
 424                         ACPI_MEMCPY ((obj_desc->buffer_field.buffer_obj)->buffer.pointer +
 425                                         obj_desc->buffer_field.base_byte_offset +
 426                                         field_datum_byte_offset,
 427                                         value, obj_desc->common_field.access_byte_width);
 428                 }
 429
 430                 status = AE_OK;
 431                 break;
 432
 433
 434         case ACPI_TYPE_LOCAL_BANK_FIELD:
 435
 436                 /*
 437                  * Ensure that the bank_value is not beyond the capacity of
 438                  * the register
 439                  */
 440                 if (acpi_ex_register_overflow (obj_desc->bank_field.bank_obj,
 441                                   (acpi_integer) obj_desc->bank_field.value)) {
 442                         return_ACPI_STATUS (AE_AML_REGISTER_LIMIT);
 443                 }
 444
 445                 /*
 446                  * For bank_fields, we must write the bank_value to the bank_register
 447                  * (itself a region_field) before we can access the data.
 448                  */
 449                 status = acpi_ex_insert_into_field (obj_desc->bank_field.bank_obj,
 450                                  &obj_desc->bank_field.value,
 451                                  sizeof (obj_desc->bank_field.value));
 452                 if (ACPI_FAILURE (status)) {
 453                         return_ACPI_STATUS (status);
 454                 }
 455
 456                 /*
 457                  * Now that the Bank has been selected, fall through to the
 458                  * region_field case and write the datum to the Operation Region
 459                  */
 460
 461                 /*lint -fallthrough */
 462
 463
 464         case ACPI_TYPE_LOCAL_REGION_FIELD:
 465                 /*
 466                  * For simple region_fields, we just directly access the owning
 467                  * Operation Region.
 468                  */
 469                 status = acpi_ex_access_region (obj_desc, field_datum_byte_offset, value,
 470                                   read_write);
 471                 break;
 472
 473
 474         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 475
 476
 477                 /*
 478                  * Ensure that the index_value is not beyond the capacity of
 479                  * the register
 480                  */
 481                 if (acpi_ex_register_overflow (obj_desc->index_field.index_obj,
 482                                   (acpi_integer) obj_desc->index_field.value)) {
 483                         return_ACPI_STATUS (AE_AML_REGISTER_LIMIT);
 484                 }
 485
 486                 /* Write the index value to the index_register (itself a region_field) */
 487
 488                 field_datum_byte_offset += obj_desc->index_field.value;
 489
 490                 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 491                                 "Write to Index Register: Value %8.8X\n",
 492                                 field_datum_byte_offset));
 493
 494                 status = acpi_ex_insert_into_field (obj_desc->index_field.index_obj,
 495                                  &field_datum_byte_offset,
 496                                  sizeof (field_datum_byte_offset));
 497                 if (ACPI_FAILURE (status)) {
 498                         return_ACPI_STATUS (status);
 499                 }
 500
 501                 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 502                                 "I/O to Data Register: value_ptr %p\n",
 503                                 value));
 504
 505                 if (read_write == ACPI_READ) {
 506                         /* Read the datum from the data_register */
 507
 508                         status = acpi_ex_extract_from_field (obj_desc->index_field.data_obj,
 509                                           value, sizeof (acpi_integer));
 510                 }
 511                 else {
 512                         /* Write the datum to the data_register */
 513
 514                         status = acpi_ex_insert_into_field (obj_desc->index_field.data_obj,
 515                                           value, sizeof (acpi_integer));
 516                 }
 517                 break;
 518
 519
 520         default:
 521
 522                 ACPI_REPORT_ERROR (("Wrong object type in field I/O %X\n",
 523                         ACPI_GET_OBJECT_TYPE (obj_desc)));
 524                 status = AE_AML_INTERNAL;
 525                 break;
 526         }
 527
 528         if (ACPI_SUCCESS (status)) {
 529                 if (read_write == ACPI_READ) {
 530                         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 531                                 "Value Read %8.8X%8.8X, Width %d\n",
 532                                 ACPI_FORMAT_UINT64 (*value),
 533                                 obj_desc->common_field.access_byte_width));
 534                 }
 535                 else {
 536                         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 537                                 "Value Written %8.8X%8.8X, Width %d\n",
 538                                 ACPI_FORMAT_UINT64 (*value),
 539                                 obj_desc->common_field.access_byte_width));
 540                 }
 541         }
 542
 543         return_ACPI_STATUS (status);
 544 }
 545
 546
 547 /*******************************************************************************
 548  *
 549  * FUNCTION:    acpi_ex_write_with_update_rule
 550  *
 551  * PARAMETERS:  obj_desc                - Field to be written
 552  *              Mask                    - bitmask within field datum
 553  *              field_value             - Value to write
 554  *              field_datum_byte_offset - Offset of datum within field
 555  *
 556  * RETURN:      Status
 557  *
 558  * DESCRIPTION: Apply the field update rule to a field write
 559  *
 560  ******************************************************************************/
 561
 562 acpi_status
 563 acpi_ex_write_with_update_rule (
 564         union acpi_operand_object       *obj_desc,
 565         acpi_integer                    mask,
 566         acpi_integer                    field_value,
 567         u32                             field_datum_byte_offset)
 568 {
 569         acpi_status                     status = AE_OK;
 570         acpi_integer                    merged_value;
 571         acpi_integer                    current_value;
 572
 573
 574         ACPI_FUNCTION_TRACE_U32 ("ex_write_with_update_rule", mask);
 575
 576
 577         /* Start with the new bits  */
 578
 579         merged_value = field_value;
 580
 581         /* If the mask is all ones, we don't need to worry about the update rule */
 582
 583         if (mask != ACPI_INTEGER_MAX) {
 584                 /* Decode the update rule */
 585
 586                 switch (obj_desc->common_field.field_flags & AML_FIELD_UPDATE_RULE_MASK) {
 587                 case AML_FIELD_UPDATE_PRESERVE:
 588                         /*
 589                          * Check if update rule needs to be applied (not if mask is all
 590                          * ones)  The left shift drops the bits we want to ignore.
 591                          */
 592                         if ((~mask << (ACPI_MUL_8 (sizeof (mask)) -
 593                                          ACPI_MUL_8 (obj_desc->common_field.access_byte_width))) != 0) {
 594                                 /*
 595                                  * Read the current contents of the byte/word/dword containing
 596                                  * the field, and merge with the new field value.
 597                                  */
 598                                 status = acpi_ex_field_datum_io (obj_desc, field_datum_byte_offset,
 599                                                   &current_value, ACPI_READ);
 600                                 if (ACPI_FAILURE (status)) {
 601                                         return_ACPI_STATUS (status);
 602                                 }
 603
 604                                 merged_value |= (current_value & ~mask);
 605                         }
 606                         break;
 607
 608                 case AML_FIELD_UPDATE_WRITE_AS_ONES:
 609
 610                         /* Set positions outside the field to all ones */
 611
 612                         merged_value |= ~mask;
 613                         break;
 614
 615                 case AML_FIELD_UPDATE_WRITE_AS_ZEROS:
 616
 617                         /* Set positions outside the field to all zeros */
 618
 619                         merged_value &= mask;
 620                         break;
 621
 622                 default:
 623
 624                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 625                                 "write_with_update_rule: Unknown update_rule setting: %X\n",
 626                                 (obj_desc->common_field.field_flags & AML_FIELD_UPDATE_RULE_MASK)));
 627                         return_ACPI_STATUS (AE_AML_OPERAND_VALUE);
 628                 }
 629         }
 630
 631         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 632                 "Mask %8.8X%8.8X, datum_offset %X, Width %X, Value %8.8X%8.8X, merged_value %8.8X%8.8X\n",
 633                 ACPI_FORMAT_UINT64 (mask),
 634                 field_datum_byte_offset,
 635                 obj_desc->common_field.access_byte_width,
 636                 ACPI_FORMAT_UINT64 (field_value),
 637                 ACPI_FORMAT_UINT64 (merged_value)));
 638
 639         /* Write the merged value */
 640
 641         status = acpi_ex_field_datum_io (obj_desc, field_datum_byte_offset,
 642                           &merged_value, ACPI_WRITE);
 643
 644         return_ACPI_STATUS (status);
 645 }
 646
 647
 648 /*******************************************************************************
 649  *
 650  * FUNCTION:    acpi_ex_extract_from_field
 651  *
 652  * PARAMETERS:  obj_desc            - Field to be read
 653  *              Buffer              - Where to store the field data
 654  *              buffer_length       - Length of Buffer
 655  *
 656  * RETURN:      Status
 657  *
 658  * DESCRIPTION: Retrieve the current value of the given field
 659  *
 660  ******************************************************************************/
 661
 662 acpi_status
 663 acpi_ex_extract_from_field (
 664         union acpi_operand_object       *obj_desc,
 665         void                            *buffer,
 666         u32                             buffer_length)
 667 {
 668         acpi_status                     status;
 669         acpi_integer                    raw_datum;
 670         acpi_integer                    merged_datum;
 671         u32                             field_offset = 0;
 672         u32                             buffer_offset = 0;
 673         u32                             buffer_tail_bits;
 674         u32                             datum_count;
 675         u32                             field_datum_count;
 676         u32                             i;
 677
 678
 679         ACPI_FUNCTION_TRACE ("ex_extract_from_field");
 680
 681
 682         /* Validate target buffer and clear it */
 683
 684         if (buffer_length < ACPI_ROUND_BITS_UP_TO_BYTES (
 685                          obj_desc->common_field.bit_length)) {
 686                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 687                         "Field size %X (bits) is too large for buffer (%X)\n",
 688                         obj_desc->common_field.bit_length, buffer_length));
 689
 690                 return_ACPI_STATUS (AE_BUFFER_OVERFLOW);
 691         }
 692         ACPI_MEMSET (buffer, 0, buffer_length);
 693
 694         /* Compute the number of datums (access width data items) */
 695
 696         datum_count = ACPI_ROUND_UP_TO (
 697                            obj_desc->common_field.bit_length,
 698                            obj_desc->common_field.access_bit_width);
 699         field_datum_count = ACPI_ROUND_UP_TO (
 700                            obj_desc->common_field.bit_length +
 701                            obj_desc->common_field.start_field_bit_offset,
 702                            obj_desc->common_field.access_bit_width);
 703
 704         /* Priming read from the field */
 705
 706         status = acpi_ex_field_datum_io (obj_desc, field_offset, &raw_datum, ACPI_READ);
 707         if (ACPI_FAILURE (status)) {
 708                 return_ACPI_STATUS (status);
 709         }
 710         merged_datum = raw_datum >> obj_desc->common_field.start_field_bit_offset;
 711
 712         /* Read the rest of the field */
 713
 714         for (i = 1; i < field_datum_count; i++) {
 715                 /* Get next input datum from the field */
 716
 717                 field_offset += obj_desc->common_field.access_byte_width;
 718                 status = acpi_ex_field_datum_io (obj_desc, field_offset,
 719                                   &raw_datum, ACPI_READ);
 720                 if (ACPI_FAILURE (status)) {
 721                         return_ACPI_STATUS (status);
 722                 }
 723
 724                 /* Merge with previous datum if necessary */
 725
 726                 merged_datum |= raw_datum <<
 727                         (obj_desc->common_field.access_bit_width -
 728                                 obj_desc->common_field.start_field_bit_offset);
 729
 730                 if (i == datum_count) {
 731                         break;
 732                 }
 733
 734                 /* Write merged datum to target buffer */
 735
 736                 ACPI_MEMCPY (((char *) buffer) + buffer_offset, &merged_datum,
 737                         ACPI_MIN(obj_desc->common_field.access_byte_width,
 738                                          buffer_length - buffer_offset));
 739
 740                 buffer_offset += obj_desc->common_field.access_byte_width;
 741                 merged_datum = raw_datum >> obj_desc->common_field.start_field_bit_offset;
 742         }
 743
 744         /* Mask off any extra bits in the last datum */
 745
 746         buffer_tail_bits = obj_desc->common_field.bit_length %
 747                            obj_desc->common_field.access_bit_width;
 748         if (buffer_tail_bits) {
 749                 merged_datum &= ACPI_MASK_BITS_ABOVE (buffer_tail_bits);
 750         }
 751
 752         /* Write the last datum to the buffer */
 753
 754         ACPI_MEMCPY (((char *) buffer) + buffer_offset, &merged_datum,
 755                 ACPI_MIN(obj_desc->common_field.access_byte_width,
 756                                  buffer_length - buffer_offset));
 757
 758         return_ACPI_STATUS (AE_OK);
 759 }
 760
 761
 762 /*******************************************************************************
 763  *
 764  * FUNCTION:    acpi_ex_insert_into_field
 765  *
 766  * PARAMETERS:  obj_desc            - Field to be written
 767  *              Buffer              - Data to be written
 768  *              buffer_length       - Length of Buffer
 769  *
 770  * RETURN:      Status
 771  *
 772  * DESCRIPTION: Store the Buffer contents into the given field
 773  *
 774  ******************************************************************************/
 775
 776 acpi_status
 777 acpi_ex_insert_into_field (
 778         union acpi_operand_object       *obj_desc,
 779         void                            *buffer,
 780         u32                             buffer_length)
 781 {
 782         acpi_status                     status;
 783         acpi_integer                    mask;
 784         acpi_integer                    merged_datum;
 785         acpi_integer                    raw_datum = 0;
 786         u32                             field_offset = 0;
 787         u32                             buffer_offset = 0;
 788         u32                             buffer_tail_bits;
 789         u32                             datum_count;
 790         u32                             field_datum_count;
 791         u32                             i;
 792
 793
 794         ACPI_FUNCTION_TRACE ("ex_insert_into_field");
 795
 796
 797         /* Validate input buffer */
 798
 799         if (buffer_length < ACPI_ROUND_BITS_UP_TO_BYTES (
 800                          obj_desc->common_field.bit_length)) {
 801                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 802                         "Field size %X (bits) is too large for buffer (%X)\n",
 803                         obj_desc->common_field.bit_length, buffer_length));
 804
 805                 return_ACPI_STATUS (AE_BUFFER_OVERFLOW);
 806         }
 807
 808         /* Compute the number of datums (access width data items) */
 809
 810         mask = ACPI_MASK_BITS_BELOW (obj_desc->common_field.start_field_bit_offset);
 811         datum_count = ACPI_ROUND_UP_TO (obj_desc->common_field.bit_length,
 812                           obj_desc->common_field.access_bit_width);
 813         field_datum_count = ACPI_ROUND_UP_TO (obj_desc->common_field.bit_length +
 814                            obj_desc->common_field.start_field_bit_offset,
 815                            obj_desc->common_field.access_bit_width);
 816
 817         /* Get initial Datum from the input buffer */
 818
 819         ACPI_MEMCPY (&raw_datum, buffer,
 820                 ACPI_MIN(obj_desc->common_field.access_byte_width,
 821                                  buffer_length - buffer_offset));
 822
 823         merged_datum = raw_datum << obj_desc->common_field.start_field_bit_offset;
 824
 825         /* Write the entire field */
 826
 827         for (i = 1; i < field_datum_count; i++) {
 828                 /* Write merged datum to the target field */
 829
 830                 merged_datum &= mask;
 831                 status = acpi_ex_write_with_update_rule (obj_desc, mask,
 832                                  merged_datum, field_offset);
 833                 if (ACPI_FAILURE (status)) {
 834                         return_ACPI_STATUS (status);
 835                 }
 836
 837                 /* Start new output datum by merging with previous input datum */
 838
 839                 field_offset += obj_desc->common_field.access_byte_width;
 840                 merged_datum = raw_datum >>
 841                         (obj_desc->common_field.access_bit_width -
 842                                 obj_desc->common_field.start_field_bit_offset);
 843                 mask = ACPI_INTEGER_MAX;
 844
 845                 if (i == datum_count) {
 846                         break;
 847                 }
 848
 849                 /* Get the next input datum from the buffer */
 850
 851                 buffer_offset += obj_desc->common_field.access_byte_width;
 852                 ACPI_MEMCPY (&raw_datum, ((char *) buffer) + buffer_offset,
 853                         ACPI_MIN(obj_desc->common_field.access_byte_width,
 854                                          buffer_length - buffer_offset));
 855                 merged_datum |= raw_datum << obj_desc->common_field.start_field_bit_offset;
 856         }
 857
 858         /* Mask off any extra bits in the last datum */
 859
 860         buffer_tail_bits = (obj_desc->common_field.bit_length +
 861                         obj_desc->common_field.start_field_bit_offset) %
 862                                 obj_desc->common_field.access_bit_width;
 863         if (buffer_tail_bits) {
 864                 mask &= ACPI_MASK_BITS_ABOVE (buffer_tail_bits);
 865         }
 866
 867         /* Write the last datum to the field */
 868
 869         merged_datum &= mask;
 870         status = acpi_ex_write_with_update_rule (obj_desc,
 871                          mask, merged_datum, field_offset);
 872
 873         return_ACPI_STATUS (status);
 874 }
 875
 876