drivers/acpi/hardware/hwregs.c

   1
   2 /*******************************************************************************
   3  *
   4  * Module Name: hwregs - Read/write access functions for the various ACPI
   5  *                       control and status registers.
   6  *
   7  ******************************************************************************/
   8
   9 /*
  10  * Copyright (C) 2000 - 2008, Intel Corp.
  11  * All rights reserved.
  12  *
  13  * Redistribution and use in source and binary forms, with or without
  14  * modification, are permitted provided that the following conditions
  15  * are met:
  16  * 1. Redistributions of source code must retain the above copyright
  17  *    notice, this list of conditions, and the following disclaimer,
  18  *    without modification.
  19  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  20  *    substantially similar to the "NO WARRANTY" disclaimer below
  21  *    ("Disclaimer") and any redistribution must be conditioned upon
  22  *    including a substantially similar Disclaimer requirement for further
  23  *    binary redistribution.
  24  * 3. Neither the names of the above-listed copyright holders nor the names
  25  *    of any contributors may be used to endorse or promote products derived
  26  *    from this software without specific prior written permission.
  27  *
  28  * Alternatively, this software may be distributed under the terms of the
  29  * GNU General Public License ("GPL") version 2 as published by the Free
  30  * Software Foundation.
  31  *
  32  * NO WARRANTY
  33  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  34  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  35  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  36  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  37  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  38  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  39  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  40  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  41  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  42  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  43  * POSSIBILITY OF SUCH DAMAGES.
  44  */
  45
  46 #include <acpi/acpi.h>
  47 #include <acpi/acnamesp.h>
  48 #include <acpi/acevents.h>
  49
  50 #define _COMPONENT          ACPI_HARDWARE
  51 ACPI_MODULE_NAME("hwregs")
  52
  53 /*******************************************************************************
  54  *
  55  * FUNCTION:    acpi_hw_clear_acpi_status
  56  *
  57  * PARAMETERS:  None
  58  *
  59  * RETURN:      None
  60  *
  61  * DESCRIPTION: Clears all fixed and general purpose status bits
  62  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
  63  *
  64  ******************************************************************************/
  65 acpi_status acpi_hw_clear_acpi_status(void)
  66 {
  67         acpi_status status;
  68         acpi_cpu_flags lock_flags = 0;
  69
  70         ACPI_FUNCTION_TRACE(hw_clear_acpi_status);
  71
  72         ACPI_DEBUG_PRINT((ACPI_DB_IO, "About to write %04X to %04X\n",
  73                           ACPI_BITMASK_ALL_FIXED_STATUS,
  74                           (u16) acpi_gbl_FADT.xpm1a_event_block.address));
  75
  76         lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
  77
  78         status = acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
  79                                         ACPI_BITMASK_ALL_FIXED_STATUS);
  80         if (ACPI_FAILURE(status)) {
  81                 goto unlock_and_exit;
  82         }
  83
  84         /* Clear the fixed events */
  85
  86         if (acpi_gbl_FADT.xpm1b_event_block.address) {
  87                 status =
  88                     acpi_hw_low_level_write(16, ACPI_BITMASK_ALL_FIXED_STATUS,
  89                                             &acpi_gbl_FADT.xpm1b_event_block);
  90                 if (ACPI_FAILURE(status)) {
  91                         goto unlock_and_exit;
  92                 }
  93         }
  94
  95         /* Clear the GPE Bits in all GPE registers in all GPE blocks */
  96
  97         status = acpi_ev_walk_gpe_list(acpi_hw_clear_gpe_block);
  98
  99       unlock_and_exit:
 100         acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
 101         return_ACPI_STATUS(status);
 102 }
 103
 104 /*******************************************************************************
 105  *
 106  * FUNCTION:    acpi_get_sleep_type_data
 107  *
 108  * PARAMETERS:  sleep_state         - Numeric sleep state
 109  *              *sleep_type_a        - Where SLP_TYPa is returned
 110  *              *sleep_type_b        - Where SLP_TYPb is returned
 111  *
 112  * RETURN:      Status - ACPI status
 113  *
 114  * DESCRIPTION: Obtain the SLP_TYPa and SLP_TYPb values for the requested sleep
 115  *              state.
 116  *
 117  ******************************************************************************/
 118
 119 acpi_status
 120 acpi_get_sleep_type_data(u8 sleep_state, u8 * sleep_type_a, u8 * sleep_type_b)
 121 {
 122         acpi_status status = AE_OK;
 123         struct acpi_evaluate_info *info;
 124
 125         ACPI_FUNCTION_TRACE(acpi_get_sleep_type_data);
 126
 127         /* Validate parameters */
 128
 129         if ((sleep_state > ACPI_S_STATES_MAX) || !sleep_type_a || !sleep_type_b) {
 130                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 131         }
 132
 133         /* Allocate the evaluation information block */
 134
 135         info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 136         if (!info) {
 137                 return_ACPI_STATUS(AE_NO_MEMORY);
 138         }
 139
 140         info->pathname =
 141             ACPI_CAST_PTR(char, acpi_gbl_sleep_state_names[sleep_state]);
 142
 143         /* Evaluate the namespace object containing the values for this state */
 144
 145         status = acpi_ns_evaluate(info);
 146         if (ACPI_FAILURE(status)) {
 147                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 148                                   "%s while evaluating SleepState [%s]\n",
 149                                   acpi_format_exception(status),
 150                                   info->pathname));
 151
 152                 goto cleanup;
 153         }
 154
 155         /* Must have a return object */
 156
 157         if (!info->return_object) {
 158                 ACPI_ERROR((AE_INFO, "No Sleep State object returned from [%s]",
 159                             info->pathname));
 160                 status = AE_NOT_EXIST;
 161         }
 162
 163         /* It must be of type Package */
 164
 165         else if (ACPI_GET_OBJECT_TYPE(info->return_object) != ACPI_TYPE_PACKAGE) {
 166                 ACPI_ERROR((AE_INFO,
 167                             "Sleep State return object is not a Package"));
 168                 status = AE_AML_OPERAND_TYPE;
 169         }
 170
 171         /*
 172          * The package must have at least two elements. NOTE (March 2005): This
 173          * goes against the current ACPI spec which defines this object as a
 174          * package with one encoded DWORD element. However, existing practice
 175          * by BIOS vendors seems to be to have 2 or more elements, at least
 176          * one per sleep type (A/B).
 177          */
 178         else if (info->return_object->package.count < 2) {
 179                 ACPI_ERROR((AE_INFO,
 180                             "Sleep State return package does not have at least two elements"));
 181                 status = AE_AML_NO_OPERAND;
 182         }
 183
 184         /* The first two elements must both be of type Integer */
 185
 186         else if ((ACPI_GET_OBJECT_TYPE(info->return_object->package.elements[0])
 187                   != ACPI_TYPE_INTEGER) ||
 188                  (ACPI_GET_OBJECT_TYPE(info->return_object->package.elements[1])
 189                   != ACPI_TYPE_INTEGER)) {
 190                 ACPI_ERROR((AE_INFO,
 191                             "Sleep State return package elements are not both Integers (%s, %s)",
 192                             acpi_ut_get_object_type_name(info->return_object->
 193                                                          package.elements[0]),
 194                             acpi_ut_get_object_type_name(info->return_object->
 195                                                          package.elements[1])));
 196                 status = AE_AML_OPERAND_TYPE;
 197         } else {
 198                 /* Valid _Sx_ package size, type, and value */
 199
 200                 *sleep_type_a = (u8)
 201                     (info->return_object->package.elements[0])->integer.value;
 202                 *sleep_type_b = (u8)
 203                     (info->return_object->package.elements[1])->integer.value;
 204         }
 205
 206         if (ACPI_FAILURE(status)) {
 207                 ACPI_EXCEPTION((AE_INFO, status,
 208                                 "While evaluating SleepState [%s], bad Sleep object %p type %s",
 209                                 info->pathname, info->return_object,
 210                                 acpi_ut_get_object_type_name(info->
 211                                                              return_object)));
 212         }
 213
 214         acpi_ut_remove_reference(info->return_object);
 215
 216       cleanup:
 217         ACPI_FREE(info);
 218         return_ACPI_STATUS(status);
 219 }
 220
 221 ACPI_EXPORT_SYMBOL(acpi_get_sleep_type_data)
 222
 223 /*******************************************************************************
 224  *
 225  * FUNCTION:    acpi_hw_get_register_bit_mask
 226  *
 227  * PARAMETERS:  register_id         - Index of ACPI Register to access
 228  *
 229  * RETURN:      The bitmask to be used when accessing the register
 230  *
 231  * DESCRIPTION: Map register_id into a register bitmask.
 232  *
 233  ******************************************************************************/
 234 struct acpi_bit_register_info *acpi_hw_get_bit_register_info(u32 register_id)
 235 {
 236         ACPI_FUNCTION_ENTRY();
 237
 238         if (register_id > ACPI_BITREG_MAX) {
 239                 ACPI_ERROR((AE_INFO, "Invalid BitRegister ID: %X",
 240                             register_id));
 241                 return (NULL);
 242         }
 243
 244         return (&acpi_gbl_bit_register_info[register_id]);
 245 }
 246
 247 /*******************************************************************************
 248  *
 249  * FUNCTION:    acpi_get_register
 250  *
 251  * PARAMETERS:  register_id     - ID of ACPI bit_register to access
 252  *              return_value    - Value that was read from the register
 253  *
 254  * RETURN:      Status and the value read from specified Register. Value
 255  *              returned is normalized to bit0 (is shifted all the way right)
 256  *
 257  * DESCRIPTION: ACPI bit_register read function.
 258  *
 259  ******************************************************************************/
 260
 261 acpi_status acpi_get_register_unlocked(u32 register_id, u32 * return_value)
 262 {
 263         u32 register_value = 0;
 264         struct acpi_bit_register_info *bit_reg_info;
 265         acpi_status status;
 266
 267         ACPI_FUNCTION_TRACE(acpi_get_register);
 268
 269         /* Get the info structure corresponding to the requested ACPI Register */
 270
 271         bit_reg_info = acpi_hw_get_bit_register_info(register_id);
 272         if (!bit_reg_info) {
 273                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 274         }
 275
 276         /* Read from the register */
 277
 278         status = acpi_hw_register_read(bit_reg_info->parent_register,
 279                                        &register_value);
 280
 281         if (ACPI_SUCCESS(status)) {
 282
 283                 /* Normalize the value that was read */
 284
 285                 register_value =
 286                     ((register_value & bit_reg_info->access_bit_mask)
 287                      >> bit_reg_info->bit_position);
 288
 289                 *return_value = register_value;
 290
 291                 ACPI_DEBUG_PRINT((ACPI_DB_IO, "Read value %8.8X register %X\n",
 292                                   register_value,
 293                                   bit_reg_info->parent_register));
 294         }
 295
 296         return_ACPI_STATUS(status);
 297 }
 298
 299 acpi_status acpi_get_register(u32 register_id, u32 * return_value)
 300 {
 301         acpi_status status;
 302         acpi_cpu_flags flags;
 303         flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
 304         status = acpi_get_register_unlocked(register_id, return_value);
 305         acpi_os_release_lock(acpi_gbl_hardware_lock, flags);
 306         return status;
 307 }
 308
 309 ACPI_EXPORT_SYMBOL(acpi_get_register)
 310
 311 /*******************************************************************************
 312  *
 313  * FUNCTION:    acpi_set_register
 314  *
 315  * PARAMETERS:  register_id     - ID of ACPI bit_register to access
 316  *              Value           - (only used on write) value to write to the
 317  *                                Register, NOT pre-normalized to the bit pos
 318  *
 319  * RETURN:      Status
 320  *
 321  * DESCRIPTION: ACPI Bit Register write function.
 322  *
 323  ******************************************************************************/
 324 acpi_status acpi_set_register(u32 register_id, u32 value)
 325 {
 326         u32 register_value = 0;
 327         struct acpi_bit_register_info *bit_reg_info;
 328         acpi_status status;
 329         acpi_cpu_flags lock_flags;
 330
 331         ACPI_FUNCTION_TRACE_U32(acpi_set_register, register_id);
 332
 333         /* Get the info structure corresponding to the requested ACPI Register */
 334
 335         bit_reg_info = acpi_hw_get_bit_register_info(register_id);
 336         if (!bit_reg_info) {
 337                 ACPI_ERROR((AE_INFO, "Bad ACPI HW RegisterId: %X",
 338                             register_id));
 339                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 340         }
 341
 342         lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
 343
 344         /* Always do a register read first so we can insert the new bits  */
 345
 346         status = acpi_hw_register_read(bit_reg_info->parent_register,
 347                                        &register_value);
 348         if (ACPI_FAILURE(status)) {
 349                 goto unlock_and_exit;
 350         }
 351
 352         /*
 353          * Decode the Register ID
 354          * Register ID = [Register block ID] | [bit ID]
 355          *
 356          * Check bit ID to fine locate Register offset.
 357          * Check Mask to determine Register offset, and then read-write.
 358          */
 359         switch (bit_reg_info->parent_register) {
 360         case ACPI_REGISTER_PM1_STATUS:
 361
 362                 /*
 363                  * Status Registers are different from the rest. Clear by
 364                  * writing 1, and writing 0 has no effect. So, the only relevant
 365                  * information is the single bit we're interested in, all others should
 366                  * be written as 0 so they will be left unchanged.
 367                  */
 368                 value = ACPI_REGISTER_PREPARE_BITS(value,
 369                                                    bit_reg_info->bit_position,
 370                                                    bit_reg_info->
 371                                                    access_bit_mask);
 372                 if (value) {
 373                         status = acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
 374                                                         (u16) value);
 375                         register_value = 0;
 376                 }
 377                 break;
 378
 379         case ACPI_REGISTER_PM1_ENABLE:
 380
 381                 ACPI_REGISTER_INSERT_VALUE(register_value,
 382                                            bit_reg_info->bit_position,
 383                                            bit_reg_info->access_bit_mask,
 384                                            value);
 385
 386                 status = acpi_hw_register_write(ACPI_REGISTER_PM1_ENABLE,
 387                                                 (u16) register_value);
 388                 break;
 389
 390         case ACPI_REGISTER_PM1_CONTROL:
 391
 392                 /*
 393                  * Write the PM1 Control register.
 394                  * Note that at this level, the fact that there are actually TWO
 395                  * registers (A and B - and B may not exist) is abstracted.
 396                  */
 397                 ACPI_DEBUG_PRINT((ACPI_DB_IO, "PM1 control: Read %X\n",
 398                                   register_value));
 399
 400                 ACPI_REGISTER_INSERT_VALUE(register_value,
 401                                            bit_reg_info->bit_position,
 402                                            bit_reg_info->access_bit_mask,
 403                                            value);
 404
 405                 status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
 406                                                 (u16) register_value);
 407                 break;
 408
 409         case ACPI_REGISTER_PM2_CONTROL:
 410
 411                 status = acpi_hw_register_read(ACPI_REGISTER_PM2_CONTROL,
 412                                                &register_value);
 413                 if (ACPI_FAILURE(status)) {
 414                         goto unlock_and_exit;
 415                 }
 416
 417                 ACPI_DEBUG_PRINT((ACPI_DB_IO,
 418                                   "PM2 control: Read %X from %8.8X%8.8X\n",
 419                                   register_value,
 420                                   ACPI_FORMAT_UINT64(acpi_gbl_FADT.
 421                                                      xpm2_control_block.
 422                                                      address)));
 423
 424                 ACPI_REGISTER_INSERT_VALUE(register_value,
 425                                            bit_reg_info->bit_position,
 426                                            bit_reg_info->access_bit_mask,
 427                                            value);
 428
 429                 ACPI_DEBUG_PRINT((ACPI_DB_IO,
 430                                   "About to write %4.4X to %8.8X%8.8X\n",
 431                                   register_value,
 432                                   ACPI_FORMAT_UINT64(acpi_gbl_FADT.
 433                                                      xpm2_control_block.
 434                                                      address)));
 435
 436                 status = acpi_hw_register_write(ACPI_REGISTER_PM2_CONTROL,
 437                                                 (u8) (register_value));
 438                 break;
 439
 440         default:
 441                 break;
 442         }
 443
 444       unlock_and_exit:
 445
 446         acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
 447
 448         /* Normalize the value that was read */
 449
 450         ACPI_DEBUG_EXEC(register_value =
 451                         ((register_value & bit_reg_info->access_bit_mask) >>
 452                          bit_reg_info->bit_position));
 453
 454         ACPI_DEBUG_PRINT((ACPI_DB_IO,
 455                           "Set bits: %8.8X actual %8.8X register %X\n", value,
 456                           register_value, bit_reg_info->parent_register));
 457         return_ACPI_STATUS(status);
 458 }
 459
 460 ACPI_EXPORT_SYMBOL(acpi_set_register)
 461
 462 /******************************************************************************
 463  *
 464  * FUNCTION:    acpi_hw_register_read
 465  *
 466  * PARAMETERS:  register_id         - ACPI Register ID
 467  *              return_value        - Where the register value is returned
 468  *
 469  * RETURN:      Status and the value read.
 470  *
 471  * DESCRIPTION: Read from the specified ACPI register
 472  *
 473  ******************************************************************************/
 474 acpi_status
 475 acpi_hw_register_read(u32 register_id, u32 * return_value)
 476 {
 477         u32 value1 = 0;
 478         u32 value2 = 0;
 479         acpi_status status;
 480
 481         ACPI_FUNCTION_TRACE(hw_register_read);
 482
 483         switch (register_id) {
 484         case ACPI_REGISTER_PM1_STATUS:  /* 16-bit access */
 485
 486                 status =
 487                     acpi_hw_low_level_read(16, &value1,
 488                                            &acpi_gbl_FADT.xpm1a_event_block);
 489                 if (ACPI_FAILURE(status)) {
 490                         goto exit;
 491                 }
 492
 493                 /* PM1B is optional */
 494
 495                 status =
 496                     acpi_hw_low_level_read(16, &value2,
 497                                            &acpi_gbl_FADT.xpm1b_event_block);
 498                 value1 |= value2;
 499                 break;
 500
 501         case ACPI_REGISTER_PM1_ENABLE:  /* 16-bit access */
 502
 503                 status =
 504                     acpi_hw_low_level_read(16, &value1, &acpi_gbl_xpm1a_enable);
 505                 if (ACPI_FAILURE(status)) {
 506                         goto exit;
 507                 }
 508
 509                 /* PM1B is optional */
 510
 511                 status =
 512                     acpi_hw_low_level_read(16, &value2, &acpi_gbl_xpm1b_enable);
 513                 value1 |= value2;
 514                 break;
 515
 516         case ACPI_REGISTER_PM1_CONTROL: /* 16-bit access */
 517
 518                 status =
 519                     acpi_hw_low_level_read(16, &value1,
 520                                            &acpi_gbl_FADT.xpm1a_control_block);
 521                 if (ACPI_FAILURE(status)) {
 522                         goto exit;
 523                 }
 524
 525                 status =
 526                     acpi_hw_low_level_read(16, &value2,
 527                                            &acpi_gbl_FADT.xpm1b_control_block);
 528                 value1 |= value2;
 529                 break;
 530
 531         case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
 532
 533                 status =
 534                     acpi_hw_low_level_read(8, &value1,
 535                                            &acpi_gbl_FADT.xpm2_control_block);
 536                 break;
 537
 538         case ACPI_REGISTER_PM_TIMER:    /* 32-bit access */
 539
 540                 status =
 541                     acpi_hw_low_level_read(32, &value1,
 542                                            &acpi_gbl_FADT.xpm_timer_block);
 543                 break;
 544
 545         case ACPI_REGISTER_SMI_COMMAND_BLOCK:   /* 8-bit access */
 546
 547                 status =
 548                     acpi_os_read_port(acpi_gbl_FADT.smi_command, &value1, 8);
 549                 break;
 550
 551         default:
 552                 ACPI_ERROR((AE_INFO, "Unknown Register ID: %X", register_id));
 553                 status = AE_BAD_PARAMETER;
 554                 break;
 555         }
 556
 557       exit:
 558
 559         if (ACPI_SUCCESS(status)) {
 560                 *return_value = value1;
 561         }
 562
 563         return_ACPI_STATUS(status);
 564 }
 565
 566 /******************************************************************************
 567  *
 568  * FUNCTION:    acpi_hw_register_write
 569  *
 570  * PARAMETERS:  register_id         - ACPI Register ID
 571  *              Value               - The value to write
 572  *
 573  * RETURN:      Status
 574  *
 575  * DESCRIPTION: Write to the specified ACPI register
 576  *
 577  * NOTE: In accordance with the ACPI specification, this function automatically
 578  * preserves the value of the following bits, meaning that these bits cannot be
 579  * changed via this interface:
 580  *
 581  * PM1_CONTROL[0] = SCI_EN
 582  * PM1_CONTROL[9]
 583  * PM1_STATUS[11]
 584  *
 585  * ACPI References:
 586  * 1) Hardware Ignored Bits: When software writes to a register with ignored
 587  *      bit fields, it preserves the ignored bit fields
 588  * 2) SCI_EN: OSPM always preserves this bit position
 589  *
 590  ******************************************************************************/
 591
 592 acpi_status acpi_hw_register_write(u32 register_id, u32 value)
 593 {
 594         acpi_status status;
 595         u32 read_value;
 596
 597         ACPI_FUNCTION_TRACE(hw_register_write);
 598
 599         switch (register_id) {
 600         case ACPI_REGISTER_PM1_STATUS:  /* 16-bit access */
 601
 602                 /* Perform a read first to preserve certain bits (per ACPI spec) */
 603
 604                 status = acpi_hw_register_read(ACPI_REGISTER_PM1_STATUS,
 605                                                &read_value);
 606                 if (ACPI_FAILURE(status)) {
 607                         goto exit;
 608                 }
 609
 610                 /* Insert the bits to be preserved */
 611
 612                 ACPI_INSERT_BITS(value, ACPI_PM1_STATUS_PRESERVED_BITS,
 613                                  read_value);
 614
 615                 /* Now we can write the data */
 616
 617                 status =
 618                     acpi_hw_low_level_write(16, value,
 619                                             &acpi_gbl_FADT.xpm1a_event_block);
 620                 if (ACPI_FAILURE(status)) {
 621                         goto exit;
 622                 }
 623
 624                 /* PM1B is optional */
 625
 626                 status =
 627                     acpi_hw_low_level_write(16, value,
 628                                             &acpi_gbl_FADT.xpm1b_event_block);
 629                 break;
 630
 631         case ACPI_REGISTER_PM1_ENABLE:  /* 16-bit access */
 632
 633                 status =
 634                     acpi_hw_low_level_write(16, value, &acpi_gbl_xpm1a_enable);
 635                 if (ACPI_FAILURE(status)) {
 636                         goto exit;
 637                 }
 638
 639                 /* PM1B is optional */
 640
 641                 status =
 642                     acpi_hw_low_level_write(16, value, &acpi_gbl_xpm1b_enable);
 643                 break;
 644
 645         case ACPI_REGISTER_PM1_CONTROL: /* 16-bit access */
 646
 647                 /*
 648                  * Perform a read first to preserve certain bits (per ACPI spec)
 649                  */
 650                 status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
 651                                                &read_value);
 652                 if (ACPI_FAILURE(status)) {
 653                         goto exit;
 654                 }
 655
 656                 /* Insert the bits to be preserved */
 657
 658                 ACPI_INSERT_BITS(value, ACPI_PM1_CONTROL_PRESERVED_BITS,
 659                                  read_value);
 660
 661                 /* Now we can write the data */
 662
 663                 status =
 664                     acpi_hw_low_level_write(16, value,
 665                                             &acpi_gbl_FADT.xpm1a_control_block);
 666                 if (ACPI_FAILURE(status)) {
 667                         goto exit;
 668                 }
 669
 670                 status =
 671                     acpi_hw_low_level_write(16, value,
 672                                             &acpi_gbl_FADT.xpm1b_control_block);
 673                 break;
 674
 675         case ACPI_REGISTER_PM1A_CONTROL:        /* 16-bit access */
 676
 677                 status =
 678                     acpi_hw_low_level_write(16, value,
 679                                             &acpi_gbl_FADT.xpm1a_control_block);
 680                 break;
 681
 682         case ACPI_REGISTER_PM1B_CONTROL:        /* 16-bit access */
 683
 684                 status =
 685                     acpi_hw_low_level_write(16, value,
 686                                             &acpi_gbl_FADT.xpm1b_control_block);
 687                 break;
 688
 689         case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
 690
 691                 status =
 692                     acpi_hw_low_level_write(8, value,
 693                                             &acpi_gbl_FADT.xpm2_control_block);
 694                 break;
 695
 696         case ACPI_REGISTER_PM_TIMER:    /* 32-bit access */
 697
 698                 status =
 699                     acpi_hw_low_level_write(32, value,
 700                                             &acpi_gbl_FADT.xpm_timer_block);
 701                 break;
 702
 703         case ACPI_REGISTER_SMI_COMMAND_BLOCK:   /* 8-bit access */
 704
 705                 /* SMI_CMD is currently always in IO space */
 706
 707                 status =
 708                     acpi_os_write_port(acpi_gbl_FADT.smi_command, value, 8);
 709                 break;
 710
 711         default:
 712                 status = AE_BAD_PARAMETER;
 713                 break;
 714         }
 715
 716       exit:
 717         return_ACPI_STATUS(status);
 718 }
 719
 720 /******************************************************************************
 721  *
 722  * FUNCTION:    acpi_hw_low_level_read
 723  *
 724  * PARAMETERS:  Width               - 8, 16, or 32
 725  *              Value               - Where the value is returned
 726  *              Reg                 - GAS register structure
 727  *
 728  * RETURN:      Status
 729  *
 730  * DESCRIPTION: Read from either memory or IO space.
 731  *
 732  ******************************************************************************/
 733
 734 acpi_status
 735 acpi_hw_low_level_read(u32 width, u32 * value, struct acpi_generic_address *reg)
 736 {
 737         u64 address;
 738         acpi_status status;
 739
 740         ACPI_FUNCTION_NAME(hw_low_level_read);
 741
 742         /*
 743          * Must have a valid pointer to a GAS structure, and
 744          * a non-zero address within. However, don't return an error
 745          * because the PM1A/B code must not fail if B isn't present.
 746          */
 747         if (!reg) {
 748                 return (AE_OK);
 749         }
 750
 751         /* Get a local copy of the address. Handles possible alignment issues */
 752
 753         ACPI_MOVE_64_TO_64(&address, &reg->address);
 754         if (!address) {
 755                 return (AE_OK);
 756         }
 757         *value = 0;
 758
 759         /*
 760          * Two address spaces supported: Memory or IO.
 761          * PCI_Config is not supported here because the GAS struct is insufficient
 762          */
 763         switch (reg->space_id) {
 764         case ACPI_ADR_SPACE_SYSTEM_MEMORY:
 765
 766                 status = acpi_os_read_memory((acpi_physical_address) address,
 767                                              value, width);
 768                 break;
 769
 770         case ACPI_ADR_SPACE_SYSTEM_IO:
 771
 772                 status =
 773                     acpi_os_read_port((acpi_io_address) address, value, width);
 774                 break;
 775
 776         default:
 777                 ACPI_ERROR((AE_INFO,
 778                             "Unsupported address space: %X", reg->space_id));
 779                 return (AE_BAD_PARAMETER);
 780         }
 781
 782         ACPI_DEBUG_PRINT((ACPI_DB_IO,
 783                           "Read:  %8.8X width %2d from %8.8X%8.8X (%s)\n",
 784                           *value, width, ACPI_FORMAT_UINT64(address),
 785                           acpi_ut_get_region_name(reg->space_id)));
 786
 787         return (status);
 788 }
 789
 790 /******************************************************************************
 791  *
 792  * FUNCTION:    acpi_hw_low_level_write
 793  *
 794  * PARAMETERS:  Width               - 8, 16, or 32
 795  *              Value               - To be written
 796  *              Reg                 - GAS register structure
 797  *
 798  * RETURN:      Status
 799  *
 800  * DESCRIPTION: Write to either memory or IO space.
 801  *
 802  ******************************************************************************/
 803
 804 acpi_status
 805 acpi_hw_low_level_write(u32 width, u32 value, struct acpi_generic_address * reg)
 806 {
 807         u64 address;
 808         acpi_status status;
 809
 810         ACPI_FUNCTION_NAME(hw_low_level_write);
 811
 812         /*
 813          * Must have a valid pointer to a GAS structure, and
 814          * a non-zero address within. However, don't return an error
 815          * because the PM1A/B code must not fail if B isn't present.
 816          */
 817         if (!reg) {
 818                 return (AE_OK);
 819         }
 820
 821         /* Get a local copy of the address. Handles possible alignment issues */
 822
 823         ACPI_MOVE_64_TO_64(&address, &reg->address);
 824         if (!address) {
 825                 return (AE_OK);
 826         }
 827
 828         /*
 829          * Two address spaces supported: Memory or IO.
 830          * PCI_Config is not supported here because the GAS struct is insufficient
 831          */
 832         switch (reg->space_id) {
 833         case ACPI_ADR_SPACE_SYSTEM_MEMORY:
 834
 835                 status = acpi_os_write_memory((acpi_physical_address) address,
 836                                               value, width);
 837                 break;
 838
 839         case ACPI_ADR_SPACE_SYSTEM_IO:
 840
 841                 status = acpi_os_write_port((acpi_io_address) address, value,
 842                                             width);
 843                 break;
 844
 845         default:
 846                 ACPI_ERROR((AE_INFO,
 847                             "Unsupported address space: %X", reg->space_id));
 848                 return (AE_BAD_PARAMETER);
 849         }
 850
 851         ACPI_DEBUG_PRINT((ACPI_DB_IO,
 852                           "Wrote: %8.8X width %2d   to %8.8X%8.8X (%s)\n",
 853                           value, width, ACPI_FORMAT_UINT64(address),
 854                           acpi_ut_get_region_name(reg->space_id)));
 855
 856         return (status);
 857 }