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