drivers/acpi/acpica/exfldio.c

   1 /******************************************************************************
   2  *
   3  * Module Name: exfldio - Aml Field I/O
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2010, 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 #include "acevents.h"
  49 #include "acdispat.h"
  50
  51 #define _COMPONENT          ACPI_EXECUTER
  52 ACPI_MODULE_NAME("exfldio")
  53
  54 /* Local prototypes */
  55 static acpi_status
  56 acpi_ex_field_datum_io(union acpi_operand_object *obj_desc,
  57                        u32 field_datum_byte_offset,
  58                        u64 *value, u32 read_write);
  59
  60 static u8
  61 acpi_ex_register_overflow(union acpi_operand_object *obj_desc, u64 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 (rgn_desc->common.type != ACPI_TYPE_REGION) {
  97                 ACPI_ERROR((AE_INFO, "Needed Region, found type 0x%X (%s)",
  98                             rgn_desc->common.type,
  99                             acpi_ut_get_object_type_name(rgn_desc)));
 100
 101                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 102         }
 103
 104         /*
 105          * If the Region Address and Length have not been previously evaluated,
 106          * evaluate them now and save the results.
 107          */
 108         if (!(rgn_desc->common.flags & AOPOBJ_DATA_VALID)) {
 109                 status = acpi_ds_get_region_arguments(rgn_desc);
 110                 if (ACPI_FAILURE(status)) {
 111                         return_ACPI_STATUS(status);
 112                 }
 113         }
 114
 115         /* Exit if Address/Length have been disallowed by the host OS */
 116
 117         if (rgn_desc->common.flags & AOPOBJ_INVALID) {
 118                 return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
 119         }
 120
 121         /*
 122          * Exit now for SMBus or IPMI address space, it has a non-linear address space
 123          * and the request cannot be directly validated
 124          */
 125         if (rgn_desc->region.space_id == ACPI_ADR_SPACE_SMBUS ||
 126             rgn_desc->region.space_id == ACPI_ADR_SPACE_IPMI) {
 127
 128                 /* SMBus or IPMI has a non-linear address space */
 129
 130                 return_ACPI_STATUS(AE_OK);
 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 <
 150             (obj_desc->common_field.base_byte_offset +
 151              field_datum_byte_offset +
 152              obj_desc->common_field.access_byte_width)) {
 153                 if (acpi_gbl_enable_interpreter_slack) {
 154                         /*
 155                          * Slack mode only:  We will go ahead and allow access to this
 156                          * field if it is within the region length rounded up to the next
 157                          * access width boundary. acpi_size cast for 64-bit compile.
 158                          */
 159                         if (ACPI_ROUND_UP(rgn_desc->region.length,
 160                                           obj_desc->common_field.
 161                                           access_byte_width) >=
 162                             ((acpi_size) obj_desc->common_field.
 163                              base_byte_offset +
 164                              obj_desc->common_field.access_byte_width +
 165                              field_datum_byte_offset)) {
 166                                 return_ACPI_STATUS(AE_OK);
 167                         }
 168                 }
 169
 170                 if (rgn_desc->region.length <
 171                     obj_desc->common_field.access_byte_width) {
 172                         /*
 173                          * This is the case where the access_type (acc_word, etc.) is wider
 174                          * than the region itself.  For example, a region of length one
 175                          * byte, and a field with Dword access specified.
 176                          */
 177                         ACPI_ERROR((AE_INFO,
 178                                     "Field [%4.4s] access width (%u bytes) too large for region [%4.4s] (length %u)",
 179                                     acpi_ut_get_node_name(obj_desc->
 180                                                           common_field.node),
 181                                     obj_desc->common_field.access_byte_width,
 182                                     acpi_ut_get_node_name(rgn_desc->region.
 183                                                           node),
 184                                     rgn_desc->region.length));
 185                 }
 186
 187                 /*
 188                  * Offset rounded up to next multiple of field width
 189                  * exceeds region length, indicate an error
 190                  */
 191                 ACPI_ERROR((AE_INFO,
 192                             "Field [%4.4s] Base+Offset+Width %u+%u+%u is beyond end of region [%4.4s] (length %u)",
 193                             acpi_ut_get_node_name(obj_desc->common_field.node),
 194                             obj_desc->common_field.base_byte_offset,
 195                             field_datum_byte_offset,
 196                             obj_desc->common_field.access_byte_width,
 197                             acpi_ut_get_node_name(rgn_desc->region.node),
 198                             rgn_desc->region.length));
 199
 200                 return_ACPI_STATUS(AE_AML_REGION_LIMIT);
 201         }
 202
 203         return_ACPI_STATUS(AE_OK);
 204 }
 205
 206 /*******************************************************************************
 207  *
 208  * FUNCTION:    acpi_ex_access_region
 209  *
 210  * PARAMETERS:  obj_desc                - Field to be read
 211  *              field_datum_byte_offset - Byte offset of this datum within the
 212  *                                        parent field
 213  *              Value                   - Where to store value (must at least
 214  *                                        64 bits)
 215  *              Function                - Read or Write flag plus other region-
 216  *                                        dependent flags
 217  *
 218  * RETURN:      Status
 219  *
 220  * DESCRIPTION: Read or Write a single field datum to an Operation Region.
 221  *
 222  ******************************************************************************/
 223
 224 acpi_status
 225 acpi_ex_access_region(union acpi_operand_object *obj_desc,
 226                       u32 field_datum_byte_offset, u64 *value, u32 function)
 227 {
 228         acpi_status status;
 229         union acpi_operand_object *rgn_desc;
 230         u32 region_offset;
 231
 232         ACPI_FUNCTION_TRACE(ex_access_region);
 233
 234         /*
 235          * Ensure that the region operands are fully evaluated and verify
 236          * the validity of the request
 237          */
 238         status = acpi_ex_setup_region(obj_desc, field_datum_byte_offset);
 239         if (ACPI_FAILURE(status)) {
 240                 return_ACPI_STATUS(status);
 241         }
 242
 243         /*
 244          * The physical address of this field datum is:
 245          *
 246          * 1) The base of the region, plus
 247          * 2) The base offset of the field, plus
 248          * 3) The current offset into the field
 249          */
 250         rgn_desc = obj_desc->common_field.region_obj;
 251         region_offset =
 252             obj_desc->common_field.base_byte_offset + field_datum_byte_offset;
 253
 254         if ((function & ACPI_IO_MASK) == ACPI_READ) {
 255                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, "[READ]"));
 256         } else {
 257                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, "[WRITE]"));
 258         }
 259
 260         ACPI_DEBUG_PRINT_RAW((ACPI_DB_BFIELD,
 261                               " Region [%s:%X], Width %X, ByteBase %X, Offset %X at %p\n",
 262                               acpi_ut_get_region_name(rgn_desc->region.
 263                                                       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, ACPI_CAST_PTR(void,
 268                                                                      (rgn_desc->
 269                                                                       region.
 270                                                                       address +
 271                                                                       region_offset))));
 272
 273         /* Invoke the appropriate address_space/op_region handler */
 274
 275         status =
 276             acpi_ev_address_space_dispatch(rgn_desc, function, region_offset,
 277                                            ACPI_MUL_8(obj_desc->common_field.
 278                                                       access_byte_width),
 279                                            value);
 280
 281         if (ACPI_FAILURE(status)) {
 282                 if (status == AE_NOT_IMPLEMENTED) {
 283                         ACPI_ERROR((AE_INFO,
 284                                     "Region %s(0x%X) not implemented",
 285                                     acpi_ut_get_region_name(rgn_desc->region.
 286                                                             space_id),
 287                                     rgn_desc->region.space_id));
 288                 } else if (status == AE_NOT_EXIST) {
 289                         ACPI_ERROR((AE_INFO,
 290                                     "Region %s(0x%X) has no handler",
 291                                     acpi_ut_get_region_name(rgn_desc->region.
 292                                                             space_id),
 293                                     rgn_desc->region.space_id));
 294                 }
 295         }
 296
 297         return_ACPI_STATUS(status);
 298 }
 299
 300 /*******************************************************************************
 301  *
 302  * FUNCTION:    acpi_ex_register_overflow
 303  *
 304  * PARAMETERS:  obj_desc                - Register(Field) to be written
 305  *              Value                   - Value to be stored
 306  *
 307  * RETURN:      TRUE if value overflows the field, FALSE otherwise
 308  *
 309  * DESCRIPTION: Check if a value is out of range of the field being written.
 310  *              Used to check if the values written to Index and Bank registers
 311  *              are out of range.  Normally, the value is simply truncated
 312  *              to fit the field, but this case is most likely a serious
 313  *              coding error in the ASL.
 314  *
 315  ******************************************************************************/
 316
 317 static u8
 318 acpi_ex_register_overflow(union acpi_operand_object *obj_desc, u64 value)
 319 {
 320
 321         if (obj_desc->common_field.bit_length >= ACPI_INTEGER_BIT_SIZE) {
 322                 /*
 323                  * The field is large enough to hold the maximum integer, so we can
 324                  * never overflow it.
 325                  */
 326                 return (FALSE);
 327         }
 328
 329         if (value >= ((u64) 1 << obj_desc->common_field.bit_length)) {
 330                 /*
 331                  * The Value is larger than the maximum value that can fit into
 332                  * the register.
 333                  */
 334                 return (TRUE);
 335         }
 336
 337         /* The Value will fit into the field with no truncation */
 338
 339         return (FALSE);
 340 }
 341
 342 /*******************************************************************************
 343  *
 344  * FUNCTION:    acpi_ex_field_datum_io
 345  *
 346  * PARAMETERS:  obj_desc                - Field to be read
 347  *              field_datum_byte_offset - Byte offset of this datum within the
 348  *                                        parent field
 349  *              Value                   - Where to store value (must be 64 bits)
 350  *              read_write              - Read or Write flag
 351  *
 352  * RETURN:      Status
 353  *
 354  * DESCRIPTION: Read or Write a single datum of a field.  The field_type is
 355  *              demultiplexed here to handle the different types of fields
 356  *              (buffer_field, region_field, index_field, bank_field)
 357  *
 358  ******************************************************************************/
 359
 360 static acpi_status
 361 acpi_ex_field_datum_io(union acpi_operand_object *obj_desc,
 362                        u32 field_datum_byte_offset, u64 *value, u32 read_write)
 363 {
 364         acpi_status status;
 365         u64 local_value;
 366
 367         ACPI_FUNCTION_TRACE_U32(ex_field_datum_io, field_datum_byte_offset);
 368
 369         if (read_write == ACPI_READ) {
 370                 if (!value) {
 371                         local_value = 0;
 372
 373                         /* To support reads without saving return value */
 374                         value = &local_value;
 375                 }
 376
 377                 /* Clear the entire return buffer first, [Very Important!] */
 378
 379                 *value = 0;
 380         }
 381
 382         /*
 383          * The four types of fields are:
 384          *
 385          * buffer_field - Read/write from/to a Buffer
 386          * region_field - Read/write from/to a Operation Region.
 387          * bank_field  - Write to a Bank Register, then read/write from/to an
 388          *               operation_region
 389          * index_field - Write to an Index Register, then read/write from/to a
 390          *               Data Register
 391          */
 392         switch (obj_desc->common.type) {
 393         case ACPI_TYPE_BUFFER_FIELD:
 394                 /*
 395                  * If the buffer_field arguments have not been previously evaluated,
 396                  * evaluate them now and save the results.
 397                  */
 398                 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 399                         status = acpi_ds_get_buffer_field_arguments(obj_desc);
 400                         if (ACPI_FAILURE(status)) {
 401                                 return_ACPI_STATUS(status);
 402                         }
 403                 }
 404
 405                 if (read_write == ACPI_READ) {
 406                         /*
 407                          * Copy the data from the source buffer.
 408                          * Length is the field width in bytes.
 409                          */
 410                         ACPI_MEMCPY(value,
 411                                     (obj_desc->buffer_field.buffer_obj)->buffer.
 412                                     pointer +
 413                                     obj_desc->buffer_field.base_byte_offset +
 414                                     field_datum_byte_offset,
 415                                     obj_desc->common_field.access_byte_width);
 416                 } else {
 417                         /*
 418                          * Copy the data to the target buffer.
 419                          * Length is the field width in bytes.
 420                          */
 421                         ACPI_MEMCPY((obj_desc->buffer_field.buffer_obj)->buffer.
 422                                     pointer +
 423                                     obj_desc->buffer_field.base_byte_offset +
 424                                     field_datum_byte_offset, value,
 425                                     obj_desc->common_field.access_byte_width);
 426                 }
 427
 428                 status = AE_OK;
 429                 break;
 430
 431         case ACPI_TYPE_LOCAL_BANK_FIELD:
 432
 433                 /*
 434                  * Ensure that the bank_value is not beyond the capacity of
 435                  * the register
 436                  */
 437                 if (acpi_ex_register_overflow(obj_desc->bank_field.bank_obj,
 438                                               (u64) obj_desc->bank_field.
 439                                               value)) {
 440                         return_ACPI_STATUS(AE_AML_REGISTER_LIMIT);
 441                 }
 442
 443                 /*
 444                  * For bank_fields, we must write the bank_value to the bank_register
 445                  * (itself a region_field) before we can access the data.
 446                  */
 447                 status =
 448                     acpi_ex_insert_into_field(obj_desc->bank_field.bank_obj,
 449                                               &obj_desc->bank_field.value,
 450                                               sizeof(obj_desc->bank_field.
 451                                                      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         case ACPI_TYPE_LOCAL_REGION_FIELD:
 464                 /*
 465                  * For simple region_fields, we just directly access the owning
 466                  * Operation Region.
 467                  */
 468                 status =
 469                     acpi_ex_access_region(obj_desc, field_datum_byte_offset,
 470                                           value, read_write);
 471                 break;
 472
 473         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 474
 475                 /*
 476                  * Ensure that the index_value is not beyond the capacity of
 477                  * the register
 478                  */
 479                 if (acpi_ex_register_overflow(obj_desc->index_field.index_obj,
 480                                               (u64) obj_desc->index_field.
 481                                               value)) {
 482                         return_ACPI_STATUS(AE_AML_REGISTER_LIMIT);
 483                 }
 484
 485                 /* Write the index value to the index_register (itself a region_field) */
 486
 487                 field_datum_byte_offset += obj_desc->index_field.value;
 488
 489                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 490                                   "Write to Index Register: Value %8.8X\n",
 491                                   field_datum_byte_offset));
 492
 493                 status =
 494                     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                 if (read_write == ACPI_READ) {
 502
 503                         /* Read the datum from the data_register */
 504
 505                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 506                                           "Read from Data Register\n"));
 507
 508                         status =
 509                             acpi_ex_extract_from_field(obj_desc->index_field.
 510                                                        data_obj, value,
 511                                                        sizeof(u64));
 512                 } else {
 513                         /* Write the datum to the data_register */
 514
 515                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 516                                           "Write to Data Register: Value %8.8X%8.8X\n",
 517                                           ACPI_FORMAT_UINT64(*value)));
 518
 519                         status =
 520                             acpi_ex_insert_into_field(obj_desc->index_field.
 521                                                       data_obj, value,
 522                                                       sizeof(u64));
 523                 }
 524                 break;
 525
 526         default:
 527
 528                 ACPI_ERROR((AE_INFO, "Wrong object type in field I/O %u",
 529                             obj_desc->common.type));
 530                 status = AE_AML_INTERNAL;
 531                 break;
 532         }
 533
 534         if (ACPI_SUCCESS(status)) {
 535                 if (read_write == ACPI_READ) {
 536                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 537                                           "Value Read %8.8X%8.8X, Width %d\n",
 538                                           ACPI_FORMAT_UINT64(*value),
 539                                           obj_desc->common_field.
 540                                           access_byte_width));
 541                 } else {
 542                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 543                                           "Value Written %8.8X%8.8X, Width %d\n",
 544                                           ACPI_FORMAT_UINT64(*value),
 545                                           obj_desc->common_field.
 546                                           access_byte_width));
 547                 }
 548         }
 549
 550         return_ACPI_STATUS(status);
 551 }
 552
 553 /*******************************************************************************
 554  *
 555  * FUNCTION:    acpi_ex_write_with_update_rule
 556  *
 557  * PARAMETERS:  obj_desc                - Field to be written
 558  *              Mask                    - bitmask within field datum
 559  *              field_value             - Value to write
 560  *              field_datum_byte_offset - Offset of datum within field
 561  *
 562  * RETURN:      Status
 563  *
 564  * DESCRIPTION: Apply the field update rule to a field write
 565  *
 566  ******************************************************************************/
 567
 568 acpi_status
 569 acpi_ex_write_with_update_rule(union acpi_operand_object *obj_desc,
 570                                u64 mask,
 571                                u64 field_value, u32 field_datum_byte_offset)
 572 {
 573         acpi_status status = AE_OK;
 574         u64 merged_value;
 575         u64 current_value;
 576
 577         ACPI_FUNCTION_TRACE_U32(ex_write_with_update_rule, mask);
 578
 579         /* Start with the new bits  */
 580
 581         merged_value = field_value;
 582
 583         /* If the mask is all ones, we don't need to worry about the update rule */
 584
 585         if (mask != ACPI_UINT64_MAX) {
 586
 587                 /* Decode the update rule */
 588
 589                 switch (obj_desc->common_field.
 590                         field_flags & AML_FIELD_UPDATE_RULE_MASK) {
 591                 case AML_FIELD_UPDATE_PRESERVE:
 592                         /*
 593                          * Check if update rule needs to be applied (not if mask is all
 594                          * ones)  The left shift drops the bits we want to ignore.
 595                          */
 596                         if ((~mask << (ACPI_MUL_8(sizeof(mask)) -
 597                                        ACPI_MUL_8(obj_desc->common_field.
 598                                                   access_byte_width))) != 0) {
 599                                 /*
 600                                  * Read the current contents of the byte/word/dword containing
 601                                  * the field, and merge with the new field value.
 602                                  */
 603                                 status =
 604                                     acpi_ex_field_datum_io(obj_desc,
 605                                                            field_datum_byte_offset,
 606                                                            &current_value,
 607                                                            ACPI_READ);
 608                                 if (ACPI_FAILURE(status)) {
 609                                         return_ACPI_STATUS(status);
 610                                 }
 611
 612                                 merged_value |= (current_value & ~mask);
 613                         }
 614                         break;
 615
 616                 case AML_FIELD_UPDATE_WRITE_AS_ONES:
 617
 618                         /* Set positions outside the field to all ones */
 619
 620                         merged_value |= ~mask;
 621                         break;
 622
 623                 case AML_FIELD_UPDATE_WRITE_AS_ZEROS:
 624
 625                         /* Set positions outside the field to all zeros */
 626
 627                         merged_value &= mask;
 628                         break;
 629
 630                 default:
 631
 632                         ACPI_ERROR((AE_INFO,
 633                                     "Unknown UpdateRule value: 0x%X",
 634                                     (obj_desc->common_field.
 635                                      field_flags &
 636                                      AML_FIELD_UPDATE_RULE_MASK)));
 637                         return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
 638                 }
 639         }
 640
 641         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 642                           "Mask %8.8X%8.8X, DatumOffset %X, Width %X, Value %8.8X%8.8X, MergedValue %8.8X%8.8X\n",
 643                           ACPI_FORMAT_UINT64(mask),
 644                           field_datum_byte_offset,
 645                           obj_desc->common_field.access_byte_width,
 646                           ACPI_FORMAT_UINT64(field_value),
 647                           ACPI_FORMAT_UINT64(merged_value)));
 648
 649         /* Write the merged value */
 650
 651         status = acpi_ex_field_datum_io(obj_desc, field_datum_byte_offset,
 652                                         &merged_value, ACPI_WRITE);
 653
 654         return_ACPI_STATUS(status);
 655 }
 656
 657 /*******************************************************************************
 658  *
 659  * FUNCTION:    acpi_ex_extract_from_field
 660  *
 661  * PARAMETERS:  obj_desc            - Field to be read
 662  *              Buffer              - Where to store the field data
 663  *              buffer_length       - Length of Buffer
 664  *
 665  * RETURN:      Status
 666  *
 667  * DESCRIPTION: Retrieve the current value of the given field
 668  *
 669  ******************************************************************************/
 670
 671 acpi_status
 672 acpi_ex_extract_from_field(union acpi_operand_object *obj_desc,
 673                            void *buffer, u32 buffer_length)
 674 {
 675         acpi_status status;
 676         u64 raw_datum;
 677         u64 merged_datum;
 678         u32 field_offset = 0;
 679         u32 buffer_offset = 0;
 680         u32 buffer_tail_bits;
 681         u32 datum_count;
 682         u32 field_datum_count;
 683         u32 i;
 684
 685         ACPI_FUNCTION_TRACE(ex_extract_from_field);
 686
 687         /* Validate target buffer and clear it */
 688
 689         if (buffer_length <
 690             ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.bit_length)) {
 691                 ACPI_ERROR((AE_INFO,
 692                             "Field size %u (bits) is too large for buffer (%u)",
 693                             obj_desc->common_field.bit_length, buffer_length));
 694
 695                 return_ACPI_STATUS(AE_BUFFER_OVERFLOW);
 696         }
 697         ACPI_MEMSET(buffer, 0, buffer_length);
 698
 699         /* Compute the number of datums (access width data items) */
 700
 701         datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length,
 702                                        obj_desc->common_field.access_bit_width);
 703         field_datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length +
 704                                              obj_desc->common_field.
 705                                              start_field_bit_offset,
 706                                              obj_desc->common_field.
 707                                              access_bit_width);
 708
 709         /* Priming read from the field */
 710
 711         status =
 712             acpi_ex_field_datum_io(obj_desc, field_offset, &raw_datum,
 713                                    ACPI_READ);
 714         if (ACPI_FAILURE(status)) {
 715                 return_ACPI_STATUS(status);
 716         }
 717         merged_datum =
 718             raw_datum >> obj_desc->common_field.start_field_bit_offset;
 719
 720         /* Read the rest of the field */
 721
 722         for (i = 1; i < field_datum_count; i++) {
 723
 724                 /* Get next input datum from the field */
 725
 726                 field_offset += obj_desc->common_field.access_byte_width;
 727                 status = acpi_ex_field_datum_io(obj_desc, field_offset,
 728                                                 &raw_datum, ACPI_READ);
 729                 if (ACPI_FAILURE(status)) {
 730                         return_ACPI_STATUS(status);
 731                 }
 732
 733                 /*
 734                  * Merge with previous datum if necessary.
 735                  *
 736                  * Note: Before the shift, check if the shift value will be larger than
 737                  * the integer size. If so, there is no need to perform the operation.
 738                  * This avoids the differences in behavior between different compilers
 739                  * concerning shift values larger than the target data width.
 740                  */
 741                 if ((obj_desc->common_field.access_bit_width -
 742                      obj_desc->common_field.start_field_bit_offset) <
 743                     ACPI_INTEGER_BIT_SIZE) {
 744                         merged_datum |=
 745                             raw_datum << (obj_desc->common_field.
 746                                           access_bit_width -
 747                                           obj_desc->common_field.
 748                                           start_field_bit_offset);
 749                 }
 750
 751                 if (i == datum_count) {
 752                         break;
 753                 }
 754
 755                 /* Write merged datum to target buffer */
 756
 757                 ACPI_MEMCPY(((char *)buffer) + buffer_offset, &merged_datum,
 758                             ACPI_MIN(obj_desc->common_field.access_byte_width,
 759                                      buffer_length - buffer_offset));
 760
 761                 buffer_offset += obj_desc->common_field.access_byte_width;
 762                 merged_datum =
 763                     raw_datum >> obj_desc->common_field.start_field_bit_offset;
 764         }
 765
 766         /* Mask off any extra bits in the last datum */
 767
 768         buffer_tail_bits = obj_desc->common_field.bit_length %
 769             obj_desc->common_field.access_bit_width;
 770         if (buffer_tail_bits) {
 771                 merged_datum &= ACPI_MASK_BITS_ABOVE(buffer_tail_bits);
 772         }
 773
 774         /* Write the last datum to the buffer */
 775
 776         ACPI_MEMCPY(((char *)buffer) + buffer_offset, &merged_datum,
 777                     ACPI_MIN(obj_desc->common_field.access_byte_width,
 778                              buffer_length - buffer_offset));
 779
 780         return_ACPI_STATUS(AE_OK);
 781 }
 782
 783 /*******************************************************************************
 784  *
 785  * FUNCTION:    acpi_ex_insert_into_field
 786  *
 787  * PARAMETERS:  obj_desc            - Field to be written
 788  *              Buffer              - Data to be written
 789  *              buffer_length       - Length of Buffer
 790  *
 791  * RETURN:      Status
 792  *
 793  * DESCRIPTION: Store the Buffer contents into the given field
 794  *
 795  ******************************************************************************/
 796
 797 acpi_status
 798 acpi_ex_insert_into_field(union acpi_operand_object *obj_desc,
 799                           void *buffer, u32 buffer_length)
 800 {
 801         acpi_status status;
 802         u64 mask;
 803         u64 width_mask;
 804         u64 merged_datum;
 805         u64 raw_datum = 0;
 806         u32 field_offset = 0;
 807         u32 buffer_offset = 0;
 808         u32 buffer_tail_bits;
 809         u32 datum_count;
 810         u32 field_datum_count;
 811         u32 i;
 812         u32 required_length;
 813         void *new_buffer;
 814
 815         ACPI_FUNCTION_TRACE(ex_insert_into_field);
 816
 817         /* Validate input buffer */
 818
 819         new_buffer = NULL;
 820         required_length =
 821             ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.bit_length);
 822         /*
 823          * We must have a buffer that is at least as long as the field
 824          * we are writing to.  This is because individual fields are
 825          * indivisible and partial writes are not supported -- as per
 826          * the ACPI specification.
 827          */
 828         if (buffer_length < required_length) {
 829
 830                 /* We need to create a new buffer */
 831
 832                 new_buffer = ACPI_ALLOCATE_ZEROED(required_length);
 833                 if (!new_buffer) {
 834                         return_ACPI_STATUS(AE_NO_MEMORY);
 835                 }
 836
 837                 /*
 838                  * Copy the original data to the new buffer, starting
 839                  * at Byte zero.  All unused (upper) bytes of the
 840                  * buffer will be 0.
 841                  */
 842                 ACPI_MEMCPY((char *)new_buffer, (char *)buffer, buffer_length);
 843                 buffer = new_buffer;
 844                 buffer_length = required_length;
 845         }
 846
 847         /*
 848          * Create the bitmasks used for bit insertion.
 849          * Note: This if/else is used to bypass compiler differences with the
 850          * shift operator
 851          */
 852         if (obj_desc->common_field.access_bit_width == ACPI_INTEGER_BIT_SIZE) {
 853                 width_mask = ACPI_UINT64_MAX;
 854         } else {
 855                 width_mask =
 856                     ACPI_MASK_BITS_ABOVE(obj_desc->common_field.
 857                                          access_bit_width);
 858         }
 859
 860         mask = width_mask &
 861             ACPI_MASK_BITS_BELOW(obj_desc->common_field.start_field_bit_offset);
 862
 863         /* Compute the number of datums (access width data items) */
 864
 865         datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length,
 866                                        obj_desc->common_field.access_bit_width);
 867
 868         field_datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length +
 869                                              obj_desc->common_field.
 870                                              start_field_bit_offset,
 871                                              obj_desc->common_field.
 872                                              access_bit_width);
 873
 874         /* Get initial Datum from the input buffer */
 875
 876         ACPI_MEMCPY(&raw_datum, buffer,
 877                     ACPI_MIN(obj_desc->common_field.access_byte_width,
 878                              buffer_length - buffer_offset));
 879
 880         merged_datum =
 881             raw_datum << obj_desc->common_field.start_field_bit_offset;
 882
 883         /* Write the entire field */
 884
 885         for (i = 1; i < field_datum_count; i++) {
 886
 887                 /* Write merged datum to the target field */
 888
 889                 merged_datum &= mask;
 890                 status = acpi_ex_write_with_update_rule(obj_desc, mask,
 891                                                         merged_datum,
 892                                                         field_offset);
 893                 if (ACPI_FAILURE(status)) {
 894                         goto exit;
 895                 }
 896
 897                 field_offset += obj_desc->common_field.access_byte_width;
 898
 899                 /*
 900                  * Start new output datum by merging with previous input datum
 901                  * if necessary.
 902                  *
 903                  * Note: Before the shift, check if the shift value will be larger than
 904                  * the integer size. If so, there is no need to perform the operation.
 905                  * This avoids the differences in behavior between different compilers
 906                  * concerning shift values larger than the target data width.
 907                  */
 908                 if ((obj_desc->common_field.access_bit_width -
 909                      obj_desc->common_field.start_field_bit_offset) <
 910                     ACPI_INTEGER_BIT_SIZE) {
 911                         merged_datum =
 912                             raw_datum >> (obj_desc->common_field.
 913                                           access_bit_width -
 914                                           obj_desc->common_field.
 915                                           start_field_bit_offset);
 916                 } else {
 917                         merged_datum = 0;
 918                 }
 919
 920                 mask = width_mask;
 921
 922                 if (i == datum_count) {
 923                         break;
 924                 }
 925
 926                 /* Get the next input datum from the buffer */
 927
 928                 buffer_offset += obj_desc->common_field.access_byte_width;
 929                 ACPI_MEMCPY(&raw_datum, ((char *)buffer) + buffer_offset,
 930                             ACPI_MIN(obj_desc->common_field.access_byte_width,
 931                                      buffer_length - buffer_offset));
 932                 merged_datum |=
 933                     raw_datum << obj_desc->common_field.start_field_bit_offset;
 934         }
 935
 936         /* Mask off any extra bits in the last datum */
 937
 938         buffer_tail_bits = (obj_desc->common_field.bit_length +
 939                             obj_desc->common_field.start_field_bit_offset) %
 940             obj_desc->common_field.access_bit_width;
 941         if (buffer_tail_bits) {
 942                 mask &= ACPI_MASK_BITS_ABOVE(buffer_tail_bits);
 943         }
 944
 945         /* Write the last datum to the field */
 946
 947         merged_datum &= mask;
 948         status = acpi_ex_write_with_update_rule(obj_desc,
 949                                                 mask, merged_datum,
 950                                                 field_offset);
 951
 952       exit:
 953         /* Free temporary buffer if we used one */
 954
 955         if (new_buffer) {
 956                 ACPI_FREE(new_buffer);
 957         }
 958         return_ACPI_STATUS(status);
 959 }