drivers/acpi/acpica/exfldio.c

   1 /******************************************************************************
   2  *
   3  * Module Name: exfldio - Aml Field I/O
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2011, Intel Corp.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include <acpi/acpi.h>
  45 #include "accommon.h"
  46 #include "acinterp.h"
  47 #include "amlcode.h"
  48 #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
 123          * address space 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 + 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. acpi_size cast for 64-bit compile.
 157                          */
 158                         if (ACPI_ROUND_UP(rgn_desc->region.length,
 159                                           obj_desc->common_field.
 160                                           access_byte_width) >=
 161                             ((acpi_size) obj_desc->common_field.
 162                              base_byte_offset +
 163                              obj_desc->common_field.access_byte_width +
 164                              field_datum_byte_offset)) {
 165                                 return_ACPI_STATUS(AE_OK);
 166                         }
 167                 }
 168
 169                 if (rgn_desc->region.length <
 170                     obj_desc->common_field.access_byte_width) {
 171                         /*
 172                          * This is the case where the access_type (acc_word, etc.) is wider
 173                          * than the region itself.  For example, a region of length one
 174                          * byte, and a field with Dword access specified.
 175                          */
 176                         ACPI_ERROR((AE_INFO,
 177                                     "Field [%4.4s] access width (%u bytes) too large for region [%4.4s] (length %u)",
 178                                     acpi_ut_get_node_name(obj_desc->
 179                                                           common_field.node),
 180                                     obj_desc->common_field.access_byte_width,
 181                                     acpi_ut_get_node_name(rgn_desc->region.
 182                                                           node),
 183                                     rgn_desc->region.length));
 184                 }
 185
 186                 /*
 187                  * Offset rounded up to next multiple of field width
 188                  * exceeds region length, indicate an error
 189                  */
 190                 ACPI_ERROR((AE_INFO,
 191                             "Field [%4.4s] Base+Offset+Width %u+%u+%u is beyond end of region [%4.4s] (length %u)",
 192                             acpi_ut_get_node_name(obj_desc->common_field.node),
 193                             obj_desc->common_field.base_byte_offset,
 194                             field_datum_byte_offset,
 195                             obj_desc->common_field.access_byte_width,
 196                             acpi_ut_get_node_name(rgn_desc->region.node),
 197                             rgn_desc->region.length));
 198
 199                 return_ACPI_STATUS(AE_AML_REGION_LIMIT);
 200         }
 201
 202         return_ACPI_STATUS(AE_OK);
 203 }
 204
 205 /*******************************************************************************
 206  *
 207  * FUNCTION:    acpi_ex_access_region
 208  *
 209  * PARAMETERS:  obj_desc                - Field to be read
 210  *              field_datum_byte_offset - Byte offset of this datum within the
 211  *                                        parent field
 212  *              Value                   - Where to store value (must at least
 213  *                                        64 bits)
 214  *              Function                - Read or Write flag plus other region-
 215  *                                        dependent flags
 216  *
 217  * RETURN:      Status
 218  *
 219  * DESCRIPTION: Read or Write a single field datum to an Operation Region.
 220  *
 221  ******************************************************************************/
 222
 223 acpi_status
 224 acpi_ex_access_region(union acpi_operand_object *obj_desc,
 225                       u32 field_datum_byte_offset, u64 *value, u32 function)
 226 {
 227         acpi_status status;
 228         union acpi_operand_object *rgn_desc;
 229         u32 region_offset;
 230
 231         ACPI_FUNCTION_TRACE(ex_access_region);
 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         region_offset =
 251             obj_desc->common_field.base_byte_offset + field_datum_byte_offset;
 252
 253         if ((function & ACPI_IO_MASK) == ACPI_READ) {
 254                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, "[READ]"));
 255         } else {
 256                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, "[WRITE]"));
 257         }
 258
 259         ACPI_DEBUG_PRINT_RAW((ACPI_DB_BFIELD,
 260                               " Region [%s:%X], Width %X, ByteBase %X, Offset %X at %8.8X%8.8X\n",
 261                               acpi_ut_get_region_name(rgn_desc->region.
 262                                                       space_id),
 263                               rgn_desc->region.space_id,
 264                               obj_desc->common_field.access_byte_width,
 265                               obj_desc->common_field.base_byte_offset,
 266                               field_datum_byte_offset,
 267                               ACPI_FORMAT_UINT64(rgn_desc->region.address +
 268                                                  region_offset)));
 269
 270         /* Invoke the appropriate address_space/op_region handler */
 271
 272         status =
 273             acpi_ev_address_space_dispatch(rgn_desc, function, region_offset,
 274                                            ACPI_MUL_8(obj_desc->common_field.
 275                                                       access_byte_width),
 276                                            value);
 277
 278         if (ACPI_FAILURE(status)) {
 279                 if (status == AE_NOT_IMPLEMENTED) {
 280                         ACPI_ERROR((AE_INFO,
 281                                     "Region %s (ID=%u) not implemented",
 282                                     acpi_ut_get_region_name(rgn_desc->region.
 283                                                             space_id),
 284                                     rgn_desc->region.space_id));
 285                 } else if (status == AE_NOT_EXIST) {
 286                         ACPI_ERROR((AE_INFO,
 287                                     "Region %s (ID=%u) has no handler",
 288                                     acpi_ut_get_region_name(rgn_desc->region.
 289                                                             space_id),
 290                                     rgn_desc->region.space_id));
 291                 }
 292         }
 293
 294         return_ACPI_STATUS(status);
 295 }
 296
 297 /*******************************************************************************
 298  *
 299  * FUNCTION:    acpi_ex_register_overflow
 300  *
 301  * PARAMETERS:  obj_desc                - Register(Field) to be written
 302  *              Value                   - Value to be stored
 303  *
 304  * RETURN:      TRUE if value overflows the field, FALSE otherwise
 305  *
 306  * DESCRIPTION: Check if a value is out of range of the field being written.
 307  *              Used to check if the values written to Index and Bank registers
 308  *              are out of range.  Normally, the value is simply truncated
 309  *              to fit the field, but this case is most likely a serious
 310  *              coding error in the ASL.
 311  *
 312  ******************************************************************************/
 313
 314 static u8
 315 acpi_ex_register_overflow(union acpi_operand_object *obj_desc, u64 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 >= ((u64) 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  * FUNCTION:    acpi_ex_field_datum_io
 342  *
 343  * PARAMETERS:  obj_desc                - Field to be read
 344  *              field_datum_byte_offset - Byte offset of this datum within the
 345  *                                        parent field
 346  *              Value                   - Where to store value (must be 64 bits)
 347  *              read_write              - Read or Write flag
 348  *
 349  * RETURN:      Status
 350  *
 351  * DESCRIPTION: Read or Write a single datum of a field.  The field_type is
 352  *              demultiplexed here to handle the different types of fields
 353  *              (buffer_field, region_field, index_field, bank_field)
 354  *
 355  ******************************************************************************/
 356
 357 static acpi_status
 358 acpi_ex_field_datum_io(union acpi_operand_object *obj_desc,
 359                        u32 field_datum_byte_offset, u64 *value, u32 read_write)
 360 {
 361         acpi_status status;
 362         u64 local_value;
 363
 364         ACPI_FUNCTION_TRACE_U32(ex_field_datum_io, field_datum_byte_offset);
 365
 366         if (read_write == ACPI_READ) {
 367                 if (!value) {
 368                         local_value = 0;
 369
 370                         /* To support reads without saving return value */
 371                         value = &local_value;
 372                 }
 373
 374                 /* Clear the entire return buffer first, [Very Important!] */
 375
 376                 *value = 0;
 377         }
 378
 379         /*
 380          * The four types of fields are:
 381          *
 382          * buffer_field - Read/write from/to a Buffer
 383          * region_field - Read/write from/to a Operation Region.
 384          * bank_field  - Write to a Bank Register, then read/write from/to an
 385          *               operation_region
 386          * index_field - Write to an Index Register, then read/write from/to a
 387          *               Data Register
 388          */
 389         switch (obj_desc->common.type) {
 390         case ACPI_TYPE_BUFFER_FIELD:
 391                 /*
 392                  * If the buffer_field arguments have not been previously evaluated,
 393                  * evaluate them now and save the results.
 394                  */
 395                 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 396                         status = acpi_ds_get_buffer_field_arguments(obj_desc);
 397                         if (ACPI_FAILURE(status)) {
 398                                 return_ACPI_STATUS(status);
 399                         }
 400                 }
 401
 402                 if (read_write == ACPI_READ) {
 403                         /*
 404                          * Copy the data from the source buffer.
 405                          * Length is the field width in bytes.
 406                          */
 407                         ACPI_MEMCPY(value,
 408                                     (obj_desc->buffer_field.buffer_obj)->buffer.
 409                                     pointer +
 410                                     obj_desc->buffer_field.base_byte_offset +
 411                                     field_datum_byte_offset,
 412                                     obj_desc->common_field.access_byte_width);
 413                 } else {
 414                         /*
 415                          * Copy the data to the target buffer.
 416                          * Length is the field width in bytes.
 417                          */
 418                         ACPI_MEMCPY((obj_desc->buffer_field.buffer_obj)->buffer.
 419                                     pointer +
 420                                     obj_desc->buffer_field.base_byte_offset +
 421                                     field_datum_byte_offset, value,
 422                                     obj_desc->common_field.access_byte_width);
 423                 }
 424
 425                 status = AE_OK;
 426                 break;
 427
 428         case ACPI_TYPE_LOCAL_BANK_FIELD:
 429
 430                 /*
 431                  * Ensure that the bank_value is not beyond the capacity of
 432                  * the register
 433                  */
 434                 if (acpi_ex_register_overflow(obj_desc->bank_field.bank_obj,
 435                                               (u64) obj_desc->bank_field.
 436                                               value)) {
 437                         return_ACPI_STATUS(AE_AML_REGISTER_LIMIT);
 438                 }
 439
 440                 /*
 441                  * For bank_fields, we must write the bank_value to the bank_register
 442                  * (itself a region_field) before we can access the data.
 443                  */
 444                 status =
 445                     acpi_ex_insert_into_field(obj_desc->bank_field.bank_obj,
 446                                               &obj_desc->bank_field.value,
 447                                               sizeof(obj_desc->bank_field.
 448                                                      value));
 449                 if (ACPI_FAILURE(status)) {
 450                         return_ACPI_STATUS(status);
 451                 }
 452
 453                 /*
 454                  * Now that the Bank has been selected, fall through to the
 455                  * region_field case and write the datum to the Operation Region
 456                  */
 457
 458                 /*lint -fallthrough */
 459
 460         case ACPI_TYPE_LOCAL_REGION_FIELD:
 461                 /*
 462                  * For simple region_fields, we just directly access the owning
 463                  * Operation Region.
 464                  */
 465                 status =
 466                     acpi_ex_access_region(obj_desc, field_datum_byte_offset,
 467                                           value, read_write);
 468                 break;
 469
 470         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 471
 472                 /*
 473                  * Ensure that the index_value is not beyond the capacity of
 474                  * the register
 475                  */
 476                 if (acpi_ex_register_overflow(obj_desc->index_field.index_obj,
 477                                               (u64) obj_desc->index_field.
 478                                               value)) {
 479                         return_ACPI_STATUS(AE_AML_REGISTER_LIMIT);
 480                 }
 481
 482                 /* Write the index value to the index_register (itself a region_field) */
 483
 484                 field_datum_byte_offset += obj_desc->index_field.value;
 485
 486                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 487                                   "Write to Index Register: Value %8.8X\n",
 488                                   field_datum_byte_offset));
 489
 490                 status =
 491                     acpi_ex_insert_into_field(obj_desc->index_field.index_obj,
 492                                               &field_datum_byte_offset,
 493                                               sizeof(field_datum_byte_offset));
 494                 if (ACPI_FAILURE(status)) {
 495                         return_ACPI_STATUS(status);
 496                 }
 497
 498                 if (read_write == ACPI_READ) {
 499
 500                         /* Read the datum from the data_register */
 501
 502                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 503                                           "Read from Data Register\n"));
 504
 505                         status =
 506                             acpi_ex_extract_from_field(obj_desc->index_field.
 507                                                        data_obj, value,
 508                                                        sizeof(u64));
 509                 } else {
 510                         /* Write the datum to the data_register */
 511
 512                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 513                                           "Write to Data Register: Value %8.8X%8.8X\n",
 514                                           ACPI_FORMAT_UINT64(*value)));
 515
 516                         status =
 517                             acpi_ex_insert_into_field(obj_desc->index_field.
 518                                                       data_obj, value,
 519                                                       sizeof(u64));
 520                 }
 521                 break;
 522
 523         default:
 524
 525                 ACPI_ERROR((AE_INFO, "Wrong object type in field I/O %u",
 526                             obj_desc->common.type));
 527                 status = AE_AML_INTERNAL;
 528                 break;
 529         }
 530
 531         if (ACPI_SUCCESS(status)) {
 532                 if (read_write == ACPI_READ) {
 533                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 534                                           "Value Read %8.8X%8.8X, Width %u\n",
 535                                           ACPI_FORMAT_UINT64(*value),
 536                                           obj_desc->common_field.
 537                                           access_byte_width));
 538                 } else {
 539                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 540                                           "Value Written %8.8X%8.8X, Width %u\n",
 541                                           ACPI_FORMAT_UINT64(*value),
 542                                           obj_desc->common_field.
 543                                           access_byte_width));
 544                 }
 545         }
 546
 547         return_ACPI_STATUS(status);
 548 }
 549
 550 /*******************************************************************************
 551  *
 552  * FUNCTION:    acpi_ex_write_with_update_rule
 553  *
 554  * PARAMETERS:  obj_desc                - Field to be written
 555  *              Mask                    - bitmask within field datum
 556  *              field_value             - Value to write
 557  *              field_datum_byte_offset - Offset of datum within field
 558  *
 559  * RETURN:      Status
 560  *
 561  * DESCRIPTION: Apply the field update rule to a field write
 562  *
 563  ******************************************************************************/
 564
 565 acpi_status
 566 acpi_ex_write_with_update_rule(union acpi_operand_object *obj_desc,
 567                                u64 mask,
 568                                u64 field_value, u32 field_datum_byte_offset)
 569 {
 570         acpi_status status = AE_OK;
 571         u64 merged_value;
 572         u64 current_value;
 573
 574         ACPI_FUNCTION_TRACE_U32(ex_write_with_update_rule, mask);
 575
 576         /* Start with the new bits  */
 577
 578         merged_value = field_value;
 579
 580         /* If the mask is all ones, we don't need to worry about the update rule */
 581
 582         if (mask != ACPI_UINT64_MAX) {
 583
 584                 /* Decode the update rule */
 585
 586                 switch (obj_desc->common_field.
 587                         field_flags & AML_FIELD_UPDATE_RULE_MASK) {
 588                 case AML_FIELD_UPDATE_PRESERVE:
 589                         /*
 590                          * Check if update rule needs to be applied (not if mask is all
 591                          * ones)  The left shift drops the bits we want to ignore.
 592                          */
 593                         if ((~mask << (ACPI_MUL_8(sizeof(mask)) -
 594                                        ACPI_MUL_8(obj_desc->common_field.
 595                                                   access_byte_width))) != 0) {
 596                                 /*
 597                                  * Read the current contents of the byte/word/dword containing
 598                                  * the field, and merge with the new field value.
 599                                  */
 600                                 status =
 601                                     acpi_ex_field_datum_io(obj_desc,
 602                                                            field_datum_byte_offset,
 603                                                            &current_value,
 604                                                            ACPI_READ);
 605                                 if (ACPI_FAILURE(status)) {
 606                                         return_ACPI_STATUS(status);
 607                                 }
 608
 609                                 merged_value |= (current_value & ~mask);
 610                         }
 611                         break;
 612
 613                 case AML_FIELD_UPDATE_WRITE_AS_ONES:
 614
 615                         /* Set positions outside the field to all ones */
 616
 617                         merged_value |= ~mask;
 618                         break;
 619
 620                 case AML_FIELD_UPDATE_WRITE_AS_ZEROS:
 621
 622                         /* Set positions outside the field to all zeros */
 623
 624                         merged_value &= mask;
 625                         break;
 626
 627                 default:
 628
 629                         ACPI_ERROR((AE_INFO,
 630                                     "Unknown UpdateRule value: 0x%X",
 631                                     (obj_desc->common_field.
 632                                      field_flags &
 633                                      AML_FIELD_UPDATE_RULE_MASK)));
 634                         return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
 635                 }
 636         }
 637
 638         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 639                           "Mask %8.8X%8.8X, DatumOffset %X, Width %X, Value %8.8X%8.8X, MergedValue %8.8X%8.8X\n",
 640                           ACPI_FORMAT_UINT64(mask),
 641                           field_datum_byte_offset,
 642                           obj_desc->common_field.access_byte_width,
 643                           ACPI_FORMAT_UINT64(field_value),
 644                           ACPI_FORMAT_UINT64(merged_value)));
 645
 646         /* Write the merged value */
 647
 648         status = acpi_ex_field_datum_io(obj_desc, field_datum_byte_offset,
 649                                         &merged_value, ACPI_WRITE);
 650
 651         return_ACPI_STATUS(status);
 652 }
 653
 654 /*******************************************************************************
 655  *
 656  * FUNCTION:    acpi_ex_extract_from_field
 657  *
 658  * PARAMETERS:  obj_desc            - Field to be read
 659  *              Buffer              - Where to store the field data
 660  *              buffer_length       - Length of Buffer
 661  *
 662  * RETURN:      Status
 663  *
 664  * DESCRIPTION: Retrieve the current value of the given field
 665  *
 666  ******************************************************************************/
 667
 668 acpi_status
 669 acpi_ex_extract_from_field(union acpi_operand_object *obj_desc,
 670                            void *buffer, u32 buffer_length)
 671 {
 672         acpi_status status;
 673         u64 raw_datum;
 674         u64 merged_datum;
 675         u32 field_offset = 0;
 676         u32 buffer_offset = 0;
 677         u32 buffer_tail_bits;
 678         u32 datum_count;
 679         u32 field_datum_count;
 680         u32 access_bit_width;
 681         u32 i;
 682
 683         ACPI_FUNCTION_TRACE(ex_extract_from_field);
 684
 685         /* Validate target buffer and clear it */
 686
 687         if (buffer_length <
 688             ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.bit_length)) {
 689                 ACPI_ERROR((AE_INFO,
 690                             "Field size %u (bits) is too large for buffer (%u)",
 691                             obj_desc->common_field.bit_length, buffer_length));
 692
 693                 return_ACPI_STATUS(AE_BUFFER_OVERFLOW);
 694         }
 695
 696         ACPI_MEMSET(buffer, 0, buffer_length);
 697         access_bit_width = ACPI_MUL_8(obj_desc->common_field.access_byte_width);
 698
 699         /* Handle the simple case here */
 700
 701         if ((obj_desc->common_field.start_field_bit_offset == 0) &&
 702             (obj_desc->common_field.bit_length == access_bit_width)) {
 703                 if (buffer_length >= sizeof(u64)) {
 704                         status =
 705                             acpi_ex_field_datum_io(obj_desc, 0, buffer,
 706                                                    ACPI_READ);
 707                 } else {
 708                         /* Use raw_datum (u64) to handle buffers < 64 bits */
 709
 710                         status =
 711                             acpi_ex_field_datum_io(obj_desc, 0, &raw_datum,
 712                                                    ACPI_READ);
 713                         ACPI_MEMCPY(buffer, &raw_datum, buffer_length);
 714                 }
 715
 716                 return_ACPI_STATUS(status);
 717         }
 718
 719 /* TBD: Move to common setup code */
 720
 721         /* Field algorithm is limited to sizeof(u64), truncate if needed */
 722
 723         if (obj_desc->common_field.access_byte_width > sizeof(u64)) {
 724                 obj_desc->common_field.access_byte_width = sizeof(u64);
 725                 access_bit_width = sizeof(u64) * 8;
 726         }
 727
 728         /* Compute the number of datums (access width data items) */
 729
 730         datum_count =
 731             ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length,
 732                              access_bit_width);
 733
 734         field_datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length +
 735                                              obj_desc->common_field.
 736                                              start_field_bit_offset,
 737                                              access_bit_width);
 738
 739         /* Priming read from the field */
 740
 741         status =
 742             acpi_ex_field_datum_io(obj_desc, field_offset, &raw_datum,
 743                                    ACPI_READ);
 744         if (ACPI_FAILURE(status)) {
 745                 return_ACPI_STATUS(status);
 746         }
 747         merged_datum =
 748             raw_datum >> obj_desc->common_field.start_field_bit_offset;
 749
 750         /* Read the rest of the field */
 751
 752         for (i = 1; i < field_datum_count; i++) {
 753
 754                 /* Get next input datum from the field */
 755
 756                 field_offset += obj_desc->common_field.access_byte_width;
 757                 status = acpi_ex_field_datum_io(obj_desc, field_offset,
 758                                                 &raw_datum, ACPI_READ);
 759                 if (ACPI_FAILURE(status)) {
 760                         return_ACPI_STATUS(status);
 761                 }
 762
 763                 /*
 764                  * Merge with previous datum if necessary.
 765                  *
 766                  * Note: Before the shift, check if the shift value will be larger than
 767                  * the integer size. If so, there is no need to perform the operation.
 768                  * This avoids the differences in behavior between different compilers
 769                  * concerning shift values larger than the target data width.
 770                  */
 771                 if (access_bit_width -
 772                     obj_desc->common_field.start_field_bit_offset <
 773                     ACPI_INTEGER_BIT_SIZE) {
 774                         merged_datum |=
 775                             raw_datum << (access_bit_width -
 776                                           obj_desc->common_field.
 777                                           start_field_bit_offset);
 778                 }
 779
 780                 if (i == datum_count) {
 781                         break;
 782                 }
 783
 784                 /* Write merged datum to target buffer */
 785
 786                 ACPI_MEMCPY(((char *)buffer) + buffer_offset, &merged_datum,
 787                             ACPI_MIN(obj_desc->common_field.access_byte_width,
 788                                      buffer_length - buffer_offset));
 789
 790                 buffer_offset += obj_desc->common_field.access_byte_width;
 791                 merged_datum =
 792                     raw_datum >> obj_desc->common_field.start_field_bit_offset;
 793         }
 794
 795         /* Mask off any extra bits in the last datum */
 796
 797         buffer_tail_bits = obj_desc->common_field.bit_length % access_bit_width;
 798         if (buffer_tail_bits) {
 799                 merged_datum &= ACPI_MASK_BITS_ABOVE(buffer_tail_bits);
 800         }
 801
 802         /* Write the last datum to the buffer */
 803
 804         ACPI_MEMCPY(((char *)buffer) + buffer_offset, &merged_datum,
 805                     ACPI_MIN(obj_desc->common_field.access_byte_width,
 806                              buffer_length - buffer_offset));
 807
 808         return_ACPI_STATUS(AE_OK);
 809 }
 810
 811 /*******************************************************************************
 812  *
 813  * FUNCTION:    acpi_ex_insert_into_field
 814  *
 815  * PARAMETERS:  obj_desc            - Field to be written
 816  *              Buffer              - Data to be written
 817  *              buffer_length       - Length of Buffer
 818  *
 819  * RETURN:      Status
 820  *
 821  * DESCRIPTION: Store the Buffer contents into the given field
 822  *
 823  ******************************************************************************/
 824
 825 acpi_status
 826 acpi_ex_insert_into_field(union acpi_operand_object *obj_desc,
 827                           void *buffer, u32 buffer_length)
 828 {
 829         void *new_buffer;
 830         acpi_status status;
 831         u64 mask;
 832         u64 width_mask;
 833         u64 merged_datum;
 834         u64 raw_datum = 0;
 835         u32 field_offset = 0;
 836         u32 buffer_offset = 0;
 837         u32 buffer_tail_bits;
 838         u32 datum_count;
 839         u32 field_datum_count;
 840         u32 access_bit_width;
 841         u32 required_length;
 842         u32 i;
 843
 844         ACPI_FUNCTION_TRACE(ex_insert_into_field);
 845
 846         /* Validate input buffer */
 847
 848         new_buffer = NULL;
 849         required_length =
 850             ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.bit_length);
 851         /*
 852          * We must have a buffer that is at least as long as the field
 853          * we are writing to.  This is because individual fields are
 854          * indivisible and partial writes are not supported -- as per
 855          * the ACPI specification.
 856          */
 857         if (buffer_length < required_length) {
 858
 859                 /* We need to create a new buffer */
 860
 861                 new_buffer = ACPI_ALLOCATE_ZEROED(required_length);
 862                 if (!new_buffer) {
 863                         return_ACPI_STATUS(AE_NO_MEMORY);
 864                 }
 865
 866                 /*
 867                  * Copy the original data to the new buffer, starting
 868                  * at Byte zero.  All unused (upper) bytes of the
 869                  * buffer will be 0.
 870                  */
 871                 ACPI_MEMCPY((char *)new_buffer, (char *)buffer, buffer_length);
 872                 buffer = new_buffer;
 873                 buffer_length = required_length;
 874         }
 875
 876 /* TBD: Move to common setup code */
 877
 878         /* Algo is limited to sizeof(u64), so cut the access_byte_width */
 879         if (obj_desc->common_field.access_byte_width > sizeof(u64)) {
 880                 obj_desc->common_field.access_byte_width = sizeof(u64);
 881         }
 882
 883         access_bit_width = ACPI_MUL_8(obj_desc->common_field.access_byte_width);
 884
 885         /*
 886          * Create the bitmasks used for bit insertion.
 887          * Note: This if/else is used to bypass compiler differences with the
 888          * shift operator
 889          */
 890         if (access_bit_width == ACPI_INTEGER_BIT_SIZE) {
 891                 width_mask = ACPI_UINT64_MAX;
 892         } else {
 893                 width_mask = ACPI_MASK_BITS_ABOVE(access_bit_width);
 894         }
 895
 896         mask = width_mask &
 897             ACPI_MASK_BITS_BELOW(obj_desc->common_field.start_field_bit_offset);
 898
 899         /* Compute the number of datums (access width data items) */
 900
 901         datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length,
 902                                        access_bit_width);
 903
 904         field_datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length +
 905                                              obj_desc->common_field.
 906                                              start_field_bit_offset,
 907                                              access_bit_width);
 908
 909         /* Get initial Datum from the input buffer */
 910
 911         ACPI_MEMCPY(&raw_datum, buffer,
 912                     ACPI_MIN(obj_desc->common_field.access_byte_width,
 913                              buffer_length - buffer_offset));
 914
 915         merged_datum =
 916             raw_datum << obj_desc->common_field.start_field_bit_offset;
 917
 918         /* Write the entire field */
 919
 920         for (i = 1; i < field_datum_count; i++) {
 921
 922                 /* Write merged datum to the target field */
 923
 924                 merged_datum &= mask;
 925                 status = acpi_ex_write_with_update_rule(obj_desc, mask,
 926                                                         merged_datum,
 927                                                         field_offset);
 928                 if (ACPI_FAILURE(status)) {
 929                         goto exit;
 930                 }
 931
 932                 field_offset += obj_desc->common_field.access_byte_width;
 933
 934                 /*
 935                  * Start new output datum by merging with previous input datum
 936                  * if necessary.
 937                  *
 938                  * Note: Before the shift, check if the shift value will be larger than
 939                  * the integer size. If so, there is no need to perform the operation.
 940                  * This avoids the differences in behavior between different compilers
 941                  * concerning shift values larger than the target data width.
 942                  */
 943                 if ((access_bit_width -
 944                      obj_desc->common_field.start_field_bit_offset) <
 945                     ACPI_INTEGER_BIT_SIZE) {
 946                         merged_datum =
 947                             raw_datum >> (access_bit_width -
 948                                           obj_desc->common_field.
 949                                           start_field_bit_offset);
 950                 } else {
 951                         merged_datum = 0;
 952                 }
 953
 954                 mask = width_mask;
 955
 956                 if (i == datum_count) {
 957                         break;
 958                 }
 959
 960                 /* Get the next input datum from the buffer */
 961
 962                 buffer_offset += obj_desc->common_field.access_byte_width;
 963                 ACPI_MEMCPY(&raw_datum, ((char *)buffer) + buffer_offset,
 964                             ACPI_MIN(obj_desc->common_field.access_byte_width,
 965                                      buffer_length - buffer_offset));
 966
 967                 merged_datum |=
 968                     raw_datum << obj_desc->common_field.start_field_bit_offset;
 969         }
 970
 971         /* Mask off any extra bits in the last datum */
 972
 973         buffer_tail_bits = (obj_desc->common_field.bit_length +
 974                             obj_desc->common_field.start_field_bit_offset) %
 975             access_bit_width;
 976         if (buffer_tail_bits) {
 977                 mask &= ACPI_MASK_BITS_ABOVE(buffer_tail_bits);
 978         }
 979
 980         /* Write the last datum to the field */
 981
 982         merged_datum &= mask;
 983         status = acpi_ex_write_with_update_rule(obj_desc,
 984                                                 mask, merged_datum,
 985                                                 field_offset);
 986
 987       exit:
 988         /* Free temporary buffer if we used one */
 989
 990         if (new_buffer) {
 991                 ACPI_FREE(new_buffer);
 992         }
 993         return_ACPI_STATUS(status);
 994 }