kernel/drivers/acpi/acpica/exfldio.c

   1 /******************************************************************************
   2  *
   3  * Module Name: exfldio - Aml Field I/O
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2015, 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, u64 *value, u32 read_write);
  58
  59 static u8
  60 acpi_ex_register_overflow(union acpi_operand_object *obj_desc, u64 value);
  61
  62 static acpi_status
  63 acpi_ex_setup_region(union acpi_operand_object *obj_desc,
  64                      u32 field_datum_byte_offset);
  65
  66 /*******************************************************************************
  67  *
  68  * FUNCTION:    acpi_ex_setup_region
  69  *
  70  * PARAMETERS:  obj_desc                - Field to be read or written
  71  *              field_datum_byte_offset - Byte offset of this datum within the
  72  *                                        parent field
  73  *
  74  * RETURN:      Status
  75  *
  76  * DESCRIPTION: Common processing for acpi_ex_extract_from_field and
  77  *              acpi_ex_insert_into_field. Initialize the Region if necessary and
  78  *              validate the request.
  79  *
  80  ******************************************************************************/
  81
  82 static acpi_status
  83 acpi_ex_setup_region(union acpi_operand_object *obj_desc,
  84                      u32 field_datum_byte_offset)
  85 {
  86         acpi_status status = AE_OK;
  87         union acpi_operand_object *rgn_desc;
  88         u8 space_id;
  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         space_id = rgn_desc->region.space_id;
 105
 106         /* Validate the Space ID */
 107
 108         if (!acpi_is_valid_space_id(space_id)) {
 109                 ACPI_ERROR((AE_INFO,
 110                             "Invalid/unknown Address Space ID: 0x%2.2X",
 111                             space_id));
 112                 return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID);
 113         }
 114
 115         /*
 116          * If the Region Address and Length have not been previously evaluated,
 117          * evaluate them now and save the results.
 118          */
 119         if (!(rgn_desc->common.flags & AOPOBJ_DATA_VALID)) {
 120                 status = acpi_ds_get_region_arguments(rgn_desc);
 121                 if (ACPI_FAILURE(status)) {
 122                         return_ACPI_STATUS(status);
 123                 }
 124         }
 125
 126         /*
 127          * Exit now for SMBus, GSBus or IPMI address space, it has a non-linear
 128          * address space and the request cannot be directly validated
 129          */
 130         if (space_id == ACPI_ADR_SPACE_SMBUS ||
 131             space_id == ACPI_ADR_SPACE_GSBUS ||
 132             space_id == ACPI_ADR_SPACE_IPMI) {
 133
 134                 /* SMBus or IPMI has a non-linear address space */
 135
 136                 return_ACPI_STATUS(AE_OK);
 137         }
 138 #ifdef ACPI_UNDER_DEVELOPMENT
 139         /*
 140          * If the Field access is any_acc, we can now compute the optimal
 141          * access (because we know know the length of the parent region)
 142          */
 143         if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 144                 if (ACPI_FAILURE(status)) {
 145                         return_ACPI_STATUS(status);
 146                 }
 147         }
 148 #endif
 149
 150         /*
 151          * Validate the request. The entire request from the byte offset for a
 152          * length of one field datum (access width) must fit within the region.
 153          * (Region length is specified in bytes)
 154          */
 155         if (rgn_desc->region.length <
 156             (obj_desc->common_field.base_byte_offset + field_datum_byte_offset +
 157              obj_desc->common_field.access_byte_width)) {
 158                 if (acpi_gbl_enable_interpreter_slack) {
 159                         /*
 160                          * Slack mode only:  We will go ahead and allow access to this
 161                          * field if it is within the region length rounded up to the next
 162                          * access width boundary. acpi_size cast for 64-bit compile.
 163                          */
 164                         if (ACPI_ROUND_UP(rgn_desc->region.length,
 165                                           obj_desc->common_field.
 166                                           access_byte_width) >=
 167                             ((acpi_size) obj_desc->common_field.
 168                              base_byte_offset +
 169                              obj_desc->common_field.access_byte_width +
 170                              field_datum_byte_offset)) {
 171                                 return_ACPI_STATUS(AE_OK);
 172                         }
 173                 }
 174
 175                 if (rgn_desc->region.length <
 176                     obj_desc->common_field.access_byte_width) {
 177                         /*
 178                          * This is the case where the access_type (acc_word, etc.) is wider
 179                          * than the region itself. For example, a region of length one
 180                          * byte, and a field with Dword access specified.
 181                          */
 182                         ACPI_ERROR((AE_INFO,
 183                                     "Field [%4.4s] access width (%u bytes) too large for region [%4.4s] (length %u)",
 184                                     acpi_ut_get_node_name(obj_desc->
 185                                                           common_field.node),
 186                                     obj_desc->common_field.access_byte_width,
 187                                     acpi_ut_get_node_name(rgn_desc->region.
 188                                                           node),
 189                                     rgn_desc->region.length));
 190                 }
 191
 192                 /*
 193                  * Offset rounded up to next multiple of field width
 194                  * exceeds region length, indicate an error
 195                  */
 196                 ACPI_ERROR((AE_INFO,
 197                             "Field [%4.4s] Base+Offset+Width %u+%u+%u is beyond end of region [%4.4s] (length %u)",
 198                             acpi_ut_get_node_name(obj_desc->common_field.node),
 199                             obj_desc->common_field.base_byte_offset,
 200                             field_datum_byte_offset,
 201                             obj_desc->common_field.access_byte_width,
 202                             acpi_ut_get_node_name(rgn_desc->region.node),
 203                             rgn_desc->region.length));
 204
 205                 return_ACPI_STATUS(AE_AML_REGION_LIMIT);
 206         }
 207
 208         return_ACPI_STATUS(AE_OK);
 209 }
 210
 211 /*******************************************************************************
 212  *
 213  * FUNCTION:    acpi_ex_access_region
 214  *
 215  * PARAMETERS:  obj_desc                - Field to be read
 216  *              field_datum_byte_offset - Byte offset of this datum within the
 217  *                                        parent field
 218  *              value                   - Where to store value (must at least
 219  *                                        64 bits)
 220  *              function                - Read or Write flag plus other region-
 221  *                                        dependent flags
 222  *
 223  * RETURN:      Status
 224  *
 225  * DESCRIPTION: Read or Write a single field datum to an Operation Region.
 226  *
 227  ******************************************************************************/
 228
 229 acpi_status
 230 acpi_ex_access_region(union acpi_operand_object *obj_desc,
 231                       u32 field_datum_byte_offset, u64 *value, u32 function)
 232 {
 233         acpi_status status;
 234         union acpi_operand_object *rgn_desc;
 235         u32 region_offset;
 236
 237         ACPI_FUNCTION_TRACE(ex_access_region);
 238
 239         /*
 240          * Ensure that the region operands are fully evaluated and verify
 241          * the validity of the request
 242          */
 243         status = acpi_ex_setup_region(obj_desc, field_datum_byte_offset);
 244         if (ACPI_FAILURE(status)) {
 245                 return_ACPI_STATUS(status);
 246         }
 247
 248         /*
 249          * The physical address of this field datum is:
 250          *
 251          * 1) The base of the region, plus
 252          * 2) The base offset of the field, plus
 253          * 3) The current offset into the field
 254          */
 255         rgn_desc = obj_desc->common_field.region_obj;
 256         region_offset =
 257             obj_desc->common_field.base_byte_offset + field_datum_byte_offset;
 258
 259         if ((function & ACPI_IO_MASK) == ACPI_READ) {
 260                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, "[READ]"));
 261         } else {
 262                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, "[WRITE]"));
 263         }
 264
 265         ACPI_DEBUG_PRINT_RAW((ACPI_DB_BFIELD,
 266                               " Region [%s:%X], Width %X, ByteBase %X, Offset %X at %8.8X%8.8X\n",
 267                               acpi_ut_get_region_name(rgn_desc->region.
 268                                                       space_id),
 269                               rgn_desc->region.space_id,
 270                               obj_desc->common_field.access_byte_width,
 271                               obj_desc->common_field.base_byte_offset,
 272                               field_datum_byte_offset,
 273                               ACPI_FORMAT_UINT64(rgn_desc->region.address +
 274                                                  region_offset)));
 275
 276         /* Invoke the appropriate address_space/op_region handler */
 277
 278         status = acpi_ev_address_space_dispatch(rgn_desc, obj_desc,
 279                                                 function, region_offset,
 280                                                 ACPI_MUL_8(obj_desc->
 281                                                            common_field.
 282                                                            access_byte_width),
 283                                                 value);
 284
 285         if (ACPI_FAILURE(status)) {
 286                 if (status == AE_NOT_IMPLEMENTED) {
 287                         ACPI_ERROR((AE_INFO,
 288                                     "Region %s (ID=%u) not implemented",
 289                                     acpi_ut_get_region_name(rgn_desc->region.
 290                                                             space_id),
 291                                     rgn_desc->region.space_id));
 292                 } else if (status == AE_NOT_EXIST) {
 293                         ACPI_ERROR((AE_INFO,
 294                                     "Region %s (ID=%u) has no handler",
 295                                     acpi_ut_get_region_name(rgn_desc->region.
 296                                                             space_id),
 297                                     rgn_desc->region.space_id));
 298                 }
 299         }
 300
 301         return_ACPI_STATUS(status);
 302 }
 303
 304 /*******************************************************************************
 305  *
 306  * FUNCTION:    acpi_ex_register_overflow
 307  *
 308  * PARAMETERS:  obj_desc                - Register(Field) to be written
 309  *              value                   - Value to be stored
 310  *
 311  * RETURN:      TRUE if value overflows the field, FALSE otherwise
 312  *
 313  * DESCRIPTION: Check if a value is out of range of the field being written.
 314  *              Used to check if the values written to Index and Bank registers
 315  *              are out of range. Normally, the value is simply truncated
 316  *              to fit the field, but this case is most likely a serious
 317  *              coding error in the ASL.
 318  *
 319  ******************************************************************************/
 320
 321 static u8
 322 acpi_ex_register_overflow(union acpi_operand_object *obj_desc, u64 value)
 323 {
 324
 325         if (obj_desc->common_field.bit_length >= ACPI_INTEGER_BIT_SIZE) {
 326                 /*
 327                  * The field is large enough to hold the maximum integer, so we can
 328                  * never overflow it.
 329                  */
 330                 return (FALSE);
 331         }
 332
 333         if (value >= ((u64) 1 << obj_desc->common_field.bit_length)) {
 334                 /*
 335                  * The Value is larger than the maximum value that can fit into
 336                  * the register.
 337                  */
 338                 ACPI_ERROR((AE_INFO,
 339                             "Index value 0x%8.8X%8.8X overflows field width 0x%X",
 340                             ACPI_FORMAT_UINT64(value),
 341                             obj_desc->common_field.bit_length));
 342
 343                 return (TRUE);
 344         }
 345
 346         /* The Value will fit into the field with no truncation */
 347
 348         return (FALSE);
 349 }
 350
 351 /*******************************************************************************
 352  *
 353  * FUNCTION:    acpi_ex_field_datum_io
 354  *
 355  * PARAMETERS:  obj_desc                - Field to be read
 356  *              field_datum_byte_offset - Byte offset of this datum within the
 357  *                                        parent field
 358  *              value                   - Where to store value (must be 64 bits)
 359  *              read_write              - Read or Write flag
 360  *
 361  * RETURN:      Status
 362  *
 363  * DESCRIPTION: Read or Write a single datum of a field. The field_type is
 364  *              demultiplexed here to handle the different types of fields
 365  *              (buffer_field, region_field, index_field, bank_field)
 366  *
 367  ******************************************************************************/
 368
 369 static acpi_status
 370 acpi_ex_field_datum_io(union acpi_operand_object *obj_desc,
 371                        u32 field_datum_byte_offset, u64 *value, u32 read_write)
 372 {
 373         acpi_status status;
 374         u64 local_value;
 375
 376         ACPI_FUNCTION_TRACE_U32(ex_field_datum_io, field_datum_byte_offset);
 377
 378         if (read_write == ACPI_READ) {
 379                 if (!value) {
 380                         local_value = 0;
 381
 382                         /* To support reads without saving return value */
 383                         value = &local_value;
 384                 }
 385
 386                 /* Clear the entire return buffer first, [Very Important!] */
 387
 388                 *value = 0;
 389         }
 390
 391         /*
 392          * The four types of fields are:
 393          *
 394          * buffer_field - Read/write from/to a Buffer
 395          * region_field - Read/write from/to a Operation Region.
 396          * bank_field  - Write to a Bank Register, then read/write from/to an
 397          *               operation_region
 398          * index_field - Write to an Index Register, then read/write from/to a
 399          *               Data Register
 400          */
 401         switch (obj_desc->common.type) {
 402         case ACPI_TYPE_BUFFER_FIELD:
 403                 /*
 404                  * If the buffer_field arguments have not been previously evaluated,
 405                  * evaluate them now and save the results.
 406                  */
 407                 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 408                         status = acpi_ds_get_buffer_field_arguments(obj_desc);
 409                         if (ACPI_FAILURE(status)) {
 410                                 return_ACPI_STATUS(status);
 411                         }
 412                 }
 413
 414                 if (read_write == ACPI_READ) {
 415                         /*
 416                          * Copy the data from the source buffer.
 417                          * Length is the field width in bytes.
 418                          */
 419                         ACPI_MEMCPY(value,
 420                                     (obj_desc->buffer_field.buffer_obj)->buffer.
 421                                     pointer +
 422                                     obj_desc->buffer_field.base_byte_offset +
 423                                     field_datum_byte_offset,
 424                                     obj_desc->common_field.access_byte_width);
 425                 } else {
 426                         /*
 427                          * Copy the data to the target buffer.
 428                          * Length is the field width in bytes.
 429                          */
 430                         ACPI_MEMCPY((obj_desc->buffer_field.buffer_obj)->buffer.
 431                                     pointer +
 432                                     obj_desc->buffer_field.base_byte_offset +
 433                                     field_datum_byte_offset, value,
 434                                     obj_desc->common_field.access_byte_width);
 435                 }
 436
 437                 status = AE_OK;
 438                 break;
 439
 440         case ACPI_TYPE_LOCAL_BANK_FIELD:
 441                 /*
 442                  * Ensure that the bank_value is not beyond the capacity of
 443                  * the register
 444                  */
 445                 if (acpi_ex_register_overflow(obj_desc->bank_field.bank_obj,
 446                                               (u64) obj_desc->bank_field.
 447                                               value)) {
 448                         return_ACPI_STATUS(AE_AML_REGISTER_LIMIT);
 449                 }
 450
 451                 /*
 452                  * For bank_fields, we must write the bank_value to the bank_register
 453                  * (itself a region_field) before we can access the data.
 454                  */
 455                 status =
 456                     acpi_ex_insert_into_field(obj_desc->bank_field.bank_obj,
 457                                               &obj_desc->bank_field.value,
 458                                               sizeof(obj_desc->bank_field.
 459                                                      value));
 460                 if (ACPI_FAILURE(status)) {
 461                         return_ACPI_STATUS(status);
 462                 }
 463
 464                 /*
 465                  * Now that the Bank has been selected, fall through to the
 466                  * region_field case and write the datum to the Operation Region
 467                  */
 468
 469                 /*lint -fallthrough */
 470
 471         case ACPI_TYPE_LOCAL_REGION_FIELD:
 472                 /*
 473                  * For simple region_fields, we just directly access the owning
 474                  * Operation Region.
 475                  */
 476                 status =
 477                     acpi_ex_access_region(obj_desc, field_datum_byte_offset,
 478                                           value, read_write);
 479                 break;
 480
 481         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 482                 /*
 483                  * Ensure that the index_value is not beyond the capacity of
 484                  * the register
 485                  */
 486                 if (acpi_ex_register_overflow(obj_desc->index_field.index_obj,
 487                                               (u64) obj_desc->index_field.
 488                                               value)) {
 489                         return_ACPI_STATUS(AE_AML_REGISTER_LIMIT);
 490                 }
 491
 492                 /* Write the index value to the index_register (itself a region_field) */
 493
 494                 field_datum_byte_offset += obj_desc->index_field.value;
 495
 496                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 497                                   "Write to Index Register: Value %8.8X\n",
 498                                   field_datum_byte_offset));
 499
 500                 status =
 501                     acpi_ex_insert_into_field(obj_desc->index_field.index_obj,
 502                                               &field_datum_byte_offset,
 503                                               sizeof(field_datum_byte_offset));
 504                 if (ACPI_FAILURE(status)) {
 505                         return_ACPI_STATUS(status);
 506                 }
 507
 508                 if (read_write == ACPI_READ) {
 509
 510                         /* Read the datum from the data_register */
 511
 512                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 513                                           "Read from Data Register\n"));
 514
 515                         status =
 516                             acpi_ex_extract_from_field(obj_desc->index_field.
 517                                                        data_obj, value,
 518                                                        sizeof(u64));
 519                 } else {
 520                         /* Write the datum to the data_register */
 521
 522                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 523                                           "Write to Data Register: Value %8.8X%8.8X\n",
 524                                           ACPI_FORMAT_UINT64(*value)));
 525
 526                         status =
 527                             acpi_ex_insert_into_field(obj_desc->index_field.
 528                                                       data_obj, value,
 529                                                       sizeof(u64));
 530                 }
 531                 break;
 532
 533         default:
 534
 535                 ACPI_ERROR((AE_INFO, "Wrong object type in field I/O %u",
 536                             obj_desc->common.type));
 537                 status = AE_AML_INTERNAL;
 538                 break;
 539         }
 540
 541         if (ACPI_SUCCESS(status)) {
 542                 if (read_write == ACPI_READ) {
 543                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 544                                           "Value Read %8.8X%8.8X, Width %u\n",
 545                                           ACPI_FORMAT_UINT64(*value),
 546                                           obj_desc->common_field.
 547                                           access_byte_width));
 548                 } else {
 549                         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 550                                           "Value Written %8.8X%8.8X, Width %u\n",
 551                                           ACPI_FORMAT_UINT64(*value),
 552                                           obj_desc->common_field.
 553                                           access_byte_width));
 554                 }
 555         }
 556
 557         return_ACPI_STATUS(status);
 558 }
 559
 560 /*******************************************************************************
 561  *
 562  * FUNCTION:    acpi_ex_write_with_update_rule
 563  *
 564  * PARAMETERS:  obj_desc                - Field to be written
 565  *              mask                    - bitmask within field datum
 566  *              field_value             - Value to write
 567  *              field_datum_byte_offset - Offset of datum within field
 568  *
 569  * RETURN:      Status
 570  *
 571  * DESCRIPTION: Apply the field update rule to a field write
 572  *
 573  ******************************************************************************/
 574
 575 acpi_status
 576 acpi_ex_write_with_update_rule(union acpi_operand_object *obj_desc,
 577                                u64 mask,
 578                                u64 field_value, u32 field_datum_byte_offset)
 579 {
 580         acpi_status status = AE_OK;
 581         u64 merged_value;
 582         u64 current_value;
 583
 584         ACPI_FUNCTION_TRACE_U32(ex_write_with_update_rule, mask);
 585
 586         /* Start with the new bits  */
 587
 588         merged_value = field_value;
 589
 590         /* If the mask is all ones, we don't need to worry about the update rule */
 591
 592         if (mask != ACPI_UINT64_MAX) {
 593
 594                 /* Decode the update rule */
 595
 596                 switch (obj_desc->common_field.
 597                         field_flags & AML_FIELD_UPDATE_RULE_MASK) {
 598                 case AML_FIELD_UPDATE_PRESERVE:
 599                         /*
 600                          * Check if update rule needs to be applied (not if mask is all
 601                          * ones)  The left shift drops the bits we want to ignore.
 602                          */
 603                         if ((~mask << (ACPI_MUL_8(sizeof(mask)) -
 604                                        ACPI_MUL_8(obj_desc->common_field.
 605                                                   access_byte_width))) != 0) {
 606                                 /*
 607                                  * Read the current contents of the byte/word/dword containing
 608                                  * the field, and merge with the new field value.
 609                                  */
 610                                 status =
 611                                     acpi_ex_field_datum_io(obj_desc,
 612                                                            field_datum_byte_offset,
 613                                                            &current_value,
 614                                                            ACPI_READ);
 615                                 if (ACPI_FAILURE(status)) {
 616                                         return_ACPI_STATUS(status);
 617                                 }
 618
 619                                 merged_value |= (current_value & ~mask);
 620                         }
 621                         break;
 622
 623                 case AML_FIELD_UPDATE_WRITE_AS_ONES:
 624
 625                         /* Set positions outside the field to all ones */
 626
 627                         merged_value |= ~mask;
 628                         break;
 629
 630                 case AML_FIELD_UPDATE_WRITE_AS_ZEROS:
 631
 632                         /* Set positions outside the field to all zeros */
 633
 634                         merged_value &= mask;
 635                         break;
 636
 637                 default:
 638
 639                         ACPI_ERROR((AE_INFO,
 640                                     "Unknown UpdateRule value: 0x%X",
 641                                     (obj_desc->common_field.
 642                                      field_flags &
 643                                      AML_FIELD_UPDATE_RULE_MASK)));
 644                         return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
 645                 }
 646         }
 647
 648         ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 649                           "Mask %8.8X%8.8X, DatumOffset %X, Width %X, Value %8.8X%8.8X, MergedValue %8.8X%8.8X\n",
 650                           ACPI_FORMAT_UINT64(mask),
 651                           field_datum_byte_offset,
 652                           obj_desc->common_field.access_byte_width,
 653                           ACPI_FORMAT_UINT64(field_value),
 654                           ACPI_FORMAT_UINT64(merged_value)));
 655
 656         /* Write the merged value */
 657
 658         status = acpi_ex_field_datum_io(obj_desc, field_datum_byte_offset,
 659                                         &merged_value, ACPI_WRITE);
 660
 661         return_ACPI_STATUS(status);
 662 }
 663
 664 /*******************************************************************************
 665  *
 666  * FUNCTION:    acpi_ex_extract_from_field
 667  *
 668  * PARAMETERS:  obj_desc            - Field to be read
 669  *              buffer              - Where to store the field data
 670  *              buffer_length       - Length of Buffer
 671  *
 672  * RETURN:      Status
 673  *
 674  * DESCRIPTION: Retrieve the current value of the given field
 675  *
 676  ******************************************************************************/
 677
 678 acpi_status
 679 acpi_ex_extract_from_field(union acpi_operand_object *obj_desc,
 680                            void *buffer, u32 buffer_length)
 681 {
 682         acpi_status status;
 683         u64 raw_datum;
 684         u64 merged_datum;
 685         u32 field_offset = 0;
 686         u32 buffer_offset = 0;
 687         u32 buffer_tail_bits;
 688         u32 datum_count;
 689         u32 field_datum_count;
 690         u32 access_bit_width;
 691         u32 i;
 692
 693         ACPI_FUNCTION_TRACE(ex_extract_from_field);
 694
 695         /* Validate target buffer and clear it */
 696
 697         if (buffer_length <
 698             ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.bit_length)) {
 699                 ACPI_ERROR((AE_INFO,
 700                             "Field size %u (bits) is too large for buffer (%u)",
 701                             obj_desc->common_field.bit_length, buffer_length));
 702
 703                 return_ACPI_STATUS(AE_BUFFER_OVERFLOW);
 704         }
 705
 706         ACPI_MEMSET(buffer, 0, buffer_length);
 707         access_bit_width = ACPI_MUL_8(obj_desc->common_field.access_byte_width);
 708
 709         /* Handle the simple case here */
 710
 711         if ((obj_desc->common_field.start_field_bit_offset == 0) &&
 712             (obj_desc->common_field.bit_length == access_bit_width)) {
 713                 if (buffer_length >= sizeof(u64)) {
 714                         status =
 715                             acpi_ex_field_datum_io(obj_desc, 0, buffer,
 716                                                    ACPI_READ);
 717                 } else {
 718                         /* Use raw_datum (u64) to handle buffers < 64 bits */
 719
 720                         status =
 721                             acpi_ex_field_datum_io(obj_desc, 0, &raw_datum,
 722                                                    ACPI_READ);
 723                         ACPI_MEMCPY(buffer, &raw_datum, buffer_length);
 724                 }
 725
 726                 return_ACPI_STATUS(status);
 727         }
 728
 729 /* TBD: Move to common setup code */
 730
 731         /* Field algorithm is limited to sizeof(u64), truncate if needed */
 732
 733         if (obj_desc->common_field.access_byte_width > sizeof(u64)) {
 734                 obj_desc->common_field.access_byte_width = sizeof(u64);
 735                 access_bit_width = sizeof(u64) * 8;
 736         }
 737
 738         /* Compute the number of datums (access width data items) */
 739
 740         datum_count =
 741             ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length,
 742                              access_bit_width);
 743
 744         field_datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length +
 745                                              obj_desc->common_field.
 746                                              start_field_bit_offset,
 747                                              access_bit_width);
 748
 749         /* Priming read from the field */
 750
 751         status =
 752             acpi_ex_field_datum_io(obj_desc, field_offset, &raw_datum,
 753                                    ACPI_READ);
 754         if (ACPI_FAILURE(status)) {
 755                 return_ACPI_STATUS(status);
 756         }
 757         merged_datum =
 758             raw_datum >> obj_desc->common_field.start_field_bit_offset;
 759
 760         /* Read the rest of the field */
 761
 762         for (i = 1; i < field_datum_count; i++) {
 763
 764                 /* Get next input datum from the field */
 765
 766                 field_offset += obj_desc->common_field.access_byte_width;
 767                 status = acpi_ex_field_datum_io(obj_desc, field_offset,
 768                                                 &raw_datum, ACPI_READ);
 769                 if (ACPI_FAILURE(status)) {
 770                         return_ACPI_STATUS(status);
 771                 }
 772
 773                 /*
 774                  * Merge with previous datum if necessary.
 775                  *
 776                  * Note: Before the shift, check if the shift value will be larger than
 777                  * the integer size. If so, there is no need to perform the operation.
 778                  * This avoids the differences in behavior between different compilers
 779                  * concerning shift values larger than the target data width.
 780                  */
 781                 if (access_bit_width -
 782                     obj_desc->common_field.start_field_bit_offset <
 783                     ACPI_INTEGER_BIT_SIZE) {
 784                         merged_datum |=
 785                             raw_datum << (access_bit_width -
 786                                           obj_desc->common_field.
 787                                           start_field_bit_offset);
 788                 }
 789
 790                 if (i == datum_count) {
 791                         break;
 792                 }
 793
 794                 /* Write merged datum to target buffer */
 795
 796                 ACPI_MEMCPY(((char *)buffer) + buffer_offset, &merged_datum,
 797                             ACPI_MIN(obj_desc->common_field.access_byte_width,
 798                                      buffer_length - buffer_offset));
 799
 800                 buffer_offset += obj_desc->common_field.access_byte_width;
 801                 merged_datum =
 802                     raw_datum >> obj_desc->common_field.start_field_bit_offset;
 803         }
 804
 805         /* Mask off any extra bits in the last datum */
 806
 807         buffer_tail_bits = obj_desc->common_field.bit_length % access_bit_width;
 808         if (buffer_tail_bits) {
 809                 merged_datum &= ACPI_MASK_BITS_ABOVE(buffer_tail_bits);
 810         }
 811
 812         /* Write the last datum to the buffer */
 813
 814         ACPI_MEMCPY(((char *)buffer) + buffer_offset, &merged_datum,
 815                     ACPI_MIN(obj_desc->common_field.access_byte_width,
 816                              buffer_length - buffer_offset));
 817
 818         return_ACPI_STATUS(AE_OK);
 819 }
 820
 821 /*******************************************************************************
 822  *
 823  * FUNCTION:    acpi_ex_insert_into_field
 824  *
 825  * PARAMETERS:  obj_desc            - Field to be written
 826  *              buffer              - Data to be written
 827  *              buffer_length       - Length of Buffer
 828  *
 829  * RETURN:      Status
 830  *
 831  * DESCRIPTION: Store the Buffer contents into the given field
 832  *
 833  ******************************************************************************/
 834
 835 acpi_status
 836 acpi_ex_insert_into_field(union acpi_operand_object *obj_desc,
 837                           void *buffer, u32 buffer_length)
 838 {
 839         void *new_buffer;
 840         acpi_status status;
 841         u64 mask;
 842         u64 width_mask;
 843         u64 merged_datum;
 844         u64 raw_datum = 0;
 845         u32 field_offset = 0;
 846         u32 buffer_offset = 0;
 847         u32 buffer_tail_bits;
 848         u32 datum_count;
 849         u32 field_datum_count;
 850         u32 access_bit_width;
 851         u32 required_length;
 852         u32 i;
 853
 854         ACPI_FUNCTION_TRACE(ex_insert_into_field);
 855
 856         /* Validate input buffer */
 857
 858         new_buffer = NULL;
 859         required_length =
 860             ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.bit_length);
 861         /*
 862          * We must have a buffer that is at least as long as the field
 863          * we are writing to. This is because individual fields are
 864          * indivisible and partial writes are not supported -- as per
 865          * the ACPI specification.
 866          */
 867         if (buffer_length < required_length) {
 868
 869                 /* We need to create a new buffer */
 870
 871                 new_buffer = ACPI_ALLOCATE_ZEROED(required_length);
 872                 if (!new_buffer) {
 873                         return_ACPI_STATUS(AE_NO_MEMORY);
 874                 }
 875
 876                 /*
 877                  * Copy the original data to the new buffer, starting
 878                  * at Byte zero. All unused (upper) bytes of the
 879                  * buffer will be 0.
 880                  */
 881                 ACPI_MEMCPY((char *)new_buffer, (char *)buffer, buffer_length);
 882                 buffer = new_buffer;
 883                 buffer_length = required_length;
 884         }
 885
 886 /* TBD: Move to common setup code */
 887
 888         /* Algo is limited to sizeof(u64), so cut the access_byte_width */
 889         if (obj_desc->common_field.access_byte_width > sizeof(u64)) {
 890                 obj_desc->common_field.access_byte_width = sizeof(u64);
 891         }
 892
 893         access_bit_width = ACPI_MUL_8(obj_desc->common_field.access_byte_width);
 894
 895         /*
 896          * Create the bitmasks used for bit insertion.
 897          * Note: This if/else is used to bypass compiler differences with the
 898          * shift operator
 899          */
 900         if (access_bit_width == ACPI_INTEGER_BIT_SIZE) {
 901                 width_mask = ACPI_UINT64_MAX;
 902         } else {
 903                 width_mask = ACPI_MASK_BITS_ABOVE(access_bit_width);
 904         }
 905
 906         mask = width_mask &
 907             ACPI_MASK_BITS_BELOW(obj_desc->common_field.start_field_bit_offset);
 908
 909         /* Compute the number of datums (access width data items) */
 910
 911         datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length,
 912                                        access_bit_width);
 913
 914         field_datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length +
 915                                              obj_desc->common_field.
 916                                              start_field_bit_offset,
 917                                              access_bit_width);
 918
 919         /* Get initial Datum from the input buffer */
 920
 921         ACPI_MEMCPY(&raw_datum, buffer,
 922                     ACPI_MIN(obj_desc->common_field.access_byte_width,
 923                              buffer_length - buffer_offset));
 924
 925         merged_datum =
 926             raw_datum << obj_desc->common_field.start_field_bit_offset;
 927
 928         /* Write the entire field */
 929
 930         for (i = 1; i < field_datum_count; i++) {
 931
 932                 /* Write merged datum to the target field */
 933
 934                 merged_datum &= mask;
 935                 status = acpi_ex_write_with_update_rule(obj_desc, mask,
 936                                                         merged_datum,
 937                                                         field_offset);
 938                 if (ACPI_FAILURE(status)) {
 939                         goto exit;
 940                 }
 941
 942                 field_offset += obj_desc->common_field.access_byte_width;
 943
 944                 /*
 945                  * Start new output datum by merging with previous input datum
 946                  * if necessary.
 947                  *
 948                  * Note: Before the shift, check if the shift value will be larger than
 949                  * the integer size. If so, there is no need to perform the operation.
 950                  * This avoids the differences in behavior between different compilers
 951                  * concerning shift values larger than the target data width.
 952                  */
 953                 if ((access_bit_width -
 954                      obj_desc->common_field.start_field_bit_offset) <
 955                     ACPI_INTEGER_BIT_SIZE) {
 956                         merged_datum =
 957                             raw_datum >> (access_bit_width -
 958                                           obj_desc->common_field.
 959                                           start_field_bit_offset);
 960                 } else {
 961                         merged_datum = 0;
 962                 }
 963
 964                 mask = width_mask;
 965
 966                 if (i == datum_count) {
 967                         break;
 968                 }
 969
 970                 /* Get the next input datum from the buffer */
 971
 972                 buffer_offset += obj_desc->common_field.access_byte_width;
 973                 ACPI_MEMCPY(&raw_datum, ((char *)buffer) + buffer_offset,
 974                             ACPI_MIN(obj_desc->common_field.access_byte_width,
 975                                      buffer_length - buffer_offset));
 976
 977                 merged_datum |=
 978                     raw_datum << obj_desc->common_field.start_field_bit_offset;
 979         }
 980
 981         /* Mask off any extra bits in the last datum */
 982
 983         buffer_tail_bits = (obj_desc->common_field.bit_length +
 984                             obj_desc->common_field.start_field_bit_offset) %
 985             access_bit_width;
 986         if (buffer_tail_bits) {
 987                 mask &= ACPI_MASK_BITS_ABOVE(buffer_tail_bits);
 988         }
 989
 990         /* Write the last datum to the field */
 991
 992         merged_datum &= mask;
 993         status = acpi_ex_write_with_update_rule(obj_desc,
 994                                                 mask, merged_datum,
 995                                                 field_offset);
 996
 997 exit:
 998         /* Free temporary buffer if we used one */
 999
1000         if (new_buffer) {
1001                 ACPI_FREE(new_buffer);
1002         }
1003         return_ACPI_STATUS(status);
1004 }