drivers/acpi/acpica/tbfadt.c

   1 /******************************************************************************
   2  *
   3  * Module Name: tbfadt   - FADT table utilities
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2012, 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 "actables.h"
  47
  48 #define _COMPONENT          ACPI_TABLES
  49 ACPI_MODULE_NAME("tbfadt")
  50
  51 /* Local prototypes */
  52 static ACPI_INLINE void
  53 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
  54                              u8 space_id, u8 byte_width, u64 address);
  55
  56 static void acpi_tb_convert_fadt(void);
  57
  58 static void acpi_tb_validate_fadt(void);
  59
  60 static void acpi_tb_setup_fadt_registers(void);
  61
  62 /* Table for conversion of FADT to common internal format and FADT validation */
  63
  64 typedef struct acpi_fadt_info {
  65         char *name;
  66         u16 address64;
  67         u16 address32;
  68         u16 length;
  69         u8 default_length;
  70         u8 type;
  71
  72 } acpi_fadt_info;
  73
  74 #define ACPI_FADT_OPTIONAL          0
  75 #define ACPI_FADT_REQUIRED          1
  76 #define ACPI_FADT_SEPARATE_LENGTH   2
  77
  78 static struct acpi_fadt_info fadt_info_table[] = {
  79         {"Pm1aEventBlock",
  80          ACPI_FADT_OFFSET(xpm1a_event_block),
  81          ACPI_FADT_OFFSET(pm1a_event_block),
  82          ACPI_FADT_OFFSET(pm1_event_length),
  83          ACPI_PM1_REGISTER_WIDTH * 2,   /* Enable + Status register */
  84          ACPI_FADT_REQUIRED},
  85
  86         {"Pm1bEventBlock",
  87          ACPI_FADT_OFFSET(xpm1b_event_block),
  88          ACPI_FADT_OFFSET(pm1b_event_block),
  89          ACPI_FADT_OFFSET(pm1_event_length),
  90          ACPI_PM1_REGISTER_WIDTH * 2,   /* Enable + Status register */
  91          ACPI_FADT_OPTIONAL},
  92
  93         {"Pm1aControlBlock",
  94          ACPI_FADT_OFFSET(xpm1a_control_block),
  95          ACPI_FADT_OFFSET(pm1a_control_block),
  96          ACPI_FADT_OFFSET(pm1_control_length),
  97          ACPI_PM1_REGISTER_WIDTH,
  98          ACPI_FADT_REQUIRED},
  99
 100         {"Pm1bControlBlock",
 101          ACPI_FADT_OFFSET(xpm1b_control_block),
 102          ACPI_FADT_OFFSET(pm1b_control_block),
 103          ACPI_FADT_OFFSET(pm1_control_length),
 104          ACPI_PM1_REGISTER_WIDTH,
 105          ACPI_FADT_OPTIONAL},
 106
 107         {"Pm2ControlBlock",
 108          ACPI_FADT_OFFSET(xpm2_control_block),
 109          ACPI_FADT_OFFSET(pm2_control_block),
 110          ACPI_FADT_OFFSET(pm2_control_length),
 111          ACPI_PM2_REGISTER_WIDTH,
 112          ACPI_FADT_SEPARATE_LENGTH},
 113
 114         {"PmTimerBlock",
 115          ACPI_FADT_OFFSET(xpm_timer_block),
 116          ACPI_FADT_OFFSET(pm_timer_block),
 117          ACPI_FADT_OFFSET(pm_timer_length),
 118          ACPI_PM_TIMER_WIDTH,
 119          ACPI_FADT_REQUIRED},
 120
 121         {"Gpe0Block",
 122          ACPI_FADT_OFFSET(xgpe0_block),
 123          ACPI_FADT_OFFSET(gpe0_block),
 124          ACPI_FADT_OFFSET(gpe0_block_length),
 125          0,
 126          ACPI_FADT_SEPARATE_LENGTH},
 127
 128         {"Gpe1Block",
 129          ACPI_FADT_OFFSET(xgpe1_block),
 130          ACPI_FADT_OFFSET(gpe1_block),
 131          ACPI_FADT_OFFSET(gpe1_block_length),
 132          0,
 133          ACPI_FADT_SEPARATE_LENGTH}
 134 };
 135
 136 #define ACPI_FADT_INFO_ENTRIES \
 137                         (sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info))
 138
 139 /* Table used to split Event Blocks into separate status/enable registers */
 140
 141 typedef struct acpi_fadt_pm_info {
 142         struct acpi_generic_address *target;
 143         u16 source;
 144         u8 register_num;
 145
 146 } acpi_fadt_pm_info;
 147
 148 static struct acpi_fadt_pm_info fadt_pm_info_table[] = {
 149         {&acpi_gbl_xpm1a_status,
 150          ACPI_FADT_OFFSET(xpm1a_event_block),
 151          0},
 152
 153         {&acpi_gbl_xpm1a_enable,
 154          ACPI_FADT_OFFSET(xpm1a_event_block),
 155          1},
 156
 157         {&acpi_gbl_xpm1b_status,
 158          ACPI_FADT_OFFSET(xpm1b_event_block),
 159          0},
 160
 161         {&acpi_gbl_xpm1b_enable,
 162          ACPI_FADT_OFFSET(xpm1b_event_block),
 163          1}
 164 };
 165
 166 #define ACPI_FADT_PM_INFO_ENTRIES \
 167                         (sizeof (fadt_pm_info_table) / sizeof (struct acpi_fadt_pm_info))
 168
 169 /*******************************************************************************
 170  *
 171  * FUNCTION:    acpi_tb_init_generic_address
 172  *
 173  * PARAMETERS:  generic_address     - GAS struct to be initialized
 174  *              byte_width          - Width of this register
 175  *              Address             - Address of the register
 176  *
 177  * RETURN:      None
 178  *
 179  * DESCRIPTION: Initialize a Generic Address Structure (GAS)
 180  *              See the ACPI specification for a full description and
 181  *              definition of this structure.
 182  *
 183  ******************************************************************************/
 184
 185 static ACPI_INLINE void
 186 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
 187                              u8 space_id, u8 byte_width, u64 address)
 188 {
 189
 190         /*
 191          * The 64-bit Address field is non-aligned in the byte packed
 192          * GAS struct.
 193          */
 194         ACPI_MOVE_64_TO_64(&generic_address->address, &address);
 195
 196         /* All other fields are byte-wide */
 197
 198         generic_address->space_id = space_id;
 199         generic_address->bit_width = (u8)ACPI_MUL_8(byte_width);
 200         generic_address->bit_offset = 0;
 201         generic_address->access_width = 0;      /* Access width ANY */
 202 }
 203
 204 /*******************************************************************************
 205  *
 206  * FUNCTION:    acpi_tb_parse_fadt
 207  *
 208  * PARAMETERS:  table_index         - Index for the FADT
 209  *
 210  * RETURN:      None
 211  *
 212  * DESCRIPTION: Initialize the FADT, DSDT and FACS tables
 213  *              (FADT contains the addresses of the DSDT and FACS)
 214  *
 215  ******************************************************************************/
 216
 217 void acpi_tb_parse_fadt(u32 table_index)
 218 {
 219         u32 length;
 220         struct acpi_table_header *table;
 221
 222         /*
 223          * The FADT has multiple versions with different lengths,
 224          * and it contains pointers to both the DSDT and FACS tables.
 225          *
 226          * Get a local copy of the FADT and convert it to a common format
 227          * Map entire FADT, assumed to be smaller than one page.
 228          */
 229         length = acpi_gbl_root_table_list.tables[table_index].length;
 230
 231         table =
 232             acpi_os_map_memory(acpi_gbl_root_table_list.tables[table_index].
 233                                address, length);
 234         if (!table) {
 235                 return;
 236         }
 237
 238         /*
 239          * Validate the FADT checksum before we copy the table. Ignore
 240          * checksum error as we want to try to get the DSDT and FACS.
 241          */
 242         (void)acpi_tb_verify_checksum(table, length);
 243
 244         /* Create a local copy of the FADT in common ACPI 2.0+ format */
 245
 246         acpi_tb_create_local_fadt(table, length);
 247
 248         /* All done with the real FADT, unmap it */
 249
 250         acpi_os_unmap_memory(table, length);
 251
 252         /* Obtain the DSDT and FACS tables via their addresses within the FADT */
 253
 254         acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xdsdt,
 255                               ACPI_SIG_DSDT, ACPI_TABLE_INDEX_DSDT);
 256
 257         /* If Hardware Reduced flag is set, there is no FACS */
 258
 259         if (!acpi_gbl_reduced_hardware) {
 260                 acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.
 261                                       Xfacs, ACPI_SIG_FACS,
 262                                       ACPI_TABLE_INDEX_FACS);
 263         }
 264 }
 265
 266 /*******************************************************************************
 267  *
 268  * FUNCTION:    acpi_tb_create_local_fadt
 269  *
 270  * PARAMETERS:  Table               - Pointer to BIOS FADT
 271  *              Length              - Length of the table
 272  *
 273  * RETURN:      None
 274  *
 275  * DESCRIPTION: Get a local copy of the FADT and convert it to a common format.
 276  *              Performs validation on some important FADT fields.
 277  *
 278  * NOTE:        We create a local copy of the FADT regardless of the version.
 279  *
 280  ******************************************************************************/
 281
 282 void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
 283 {
 284         /*
 285          * Check if the FADT is larger than the largest table that we expect
 286          * (the ACPI 5.0 version). If so, truncate the table, and issue
 287          * a warning.
 288          */
 289         if (length > sizeof(struct acpi_table_fadt)) {
 290                 ACPI_WARNING((AE_INFO,
 291                               "FADT (revision %u) is longer than ACPI 5.0 version, "
 292                               "truncating length %u to %u",
 293                               table->revision, length,
 294                               (u32)sizeof(struct acpi_table_fadt)));
 295         }
 296
 297         /* Clear the entire local FADT */
 298
 299         ACPI_MEMSET(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));
 300
 301         /* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */
 302
 303         ACPI_MEMCPY(&acpi_gbl_FADT, table,
 304                     ACPI_MIN(length, sizeof(struct acpi_table_fadt)));
 305
 306         /* Take a copy of the Hardware Reduced flag */
 307
 308         acpi_gbl_reduced_hardware = FALSE;
 309         if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) {
 310                 acpi_gbl_reduced_hardware = TRUE;
 311         }
 312
 313         /* Convert the local copy of the FADT to the common internal format */
 314
 315         acpi_tb_convert_fadt();
 316
 317         /* Validate FADT values now, before we make any changes */
 318
 319         acpi_tb_validate_fadt();
 320
 321         /* Initialize the global ACPI register structures */
 322
 323         acpi_tb_setup_fadt_registers();
 324 }
 325
 326 /*******************************************************************************
 327  *
 328  * FUNCTION:    acpi_tb_convert_fadt
 329  *
 330  * PARAMETERS:  None, uses acpi_gbl_FADT
 331  *
 332  * RETURN:      None
 333  *
 334  * DESCRIPTION: Converts all versions of the FADT to a common internal format.
 335  *              Expand 32-bit addresses to 64-bit as necessary.
 336  *
 337  * NOTE:        acpi_gbl_FADT must be of size (struct acpi_table_fadt),
 338  *              and must contain a copy of the actual FADT.
 339  *
 340  * Notes on 64-bit register addresses:
 341  *
 342  * After this FADT conversion, later ACPICA code will only use the 64-bit "X"
 343  * fields of the FADT for all ACPI register addresses.
 344  *
 345  * The 64-bit "X" fields are optional extensions to the original 32-bit FADT
 346  * V1.0 fields. Even if they are present in the FADT, they are optional and
 347  * are unused if the BIOS sets them to zero. Therefore, we must copy/expand
 348  * 32-bit V1.0 fields if the corresponding X field is zero.
 349  *
 350  * For ACPI 1.0 FADTs, all 32-bit address fields are expanded to the
 351  * corresponding "X" fields in the internal FADT.
 352  *
 353  * For ACPI 2.0+ FADTs, all valid (non-zero) 32-bit address fields are expanded
 354  * to the corresponding 64-bit X fields. For compatibility with other ACPI
 355  * implementations, we ignore the 64-bit field if the 32-bit field is valid,
 356  * regardless of whether the host OS is 32-bit or 64-bit.
 357  *
 358  ******************************************************************************/
 359
 360 static void acpi_tb_convert_fadt(void)
 361 {
 362         struct acpi_generic_address *address64;
 363         u32 address32;
 364         u32 i;
 365
 366         /* Update the local FADT table header length */
 367
 368         acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt);
 369
 370         /*
 371          * Expand the 32-bit FACS and DSDT addresses to 64-bit as necessary.
 372          * Later code will always use the X 64-bit field. Also, check for an
 373          * address mismatch between the 32-bit and 64-bit address fields
 374          * (FIRMWARE_CTRL/X_FIRMWARE_CTRL, DSDT/X_DSDT) which would indicate
 375          * the presence of two FACS or two DSDT tables.
 376          */
 377         if (!acpi_gbl_FADT.Xfacs) {
 378                 acpi_gbl_FADT.Xfacs = (u64) acpi_gbl_FADT.facs;
 379         } else if (acpi_gbl_FADT.facs &&
 380                    (acpi_gbl_FADT.Xfacs != (u64) acpi_gbl_FADT.facs)) {
 381                 ACPI_WARNING((AE_INFO,
 382                     "32/64 FACS address mismatch in FADT - two FACS tables!"));
 383         }
 384
 385         if (!acpi_gbl_FADT.Xdsdt) {
 386                 acpi_gbl_FADT.Xdsdt = (u64) acpi_gbl_FADT.dsdt;
 387         } else if (acpi_gbl_FADT.dsdt &&
 388                    (acpi_gbl_FADT.Xdsdt != (u64) acpi_gbl_FADT.dsdt)) {
 389                 ACPI_WARNING((AE_INFO,
 390                     "32/64 DSDT address mismatch in FADT - two DSDT tables!"));
 391         }
 392
 393         /*
 394          * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which
 395          * should be zero are indeed zero. This will workaround BIOSs that
 396          * inadvertently place values in these fields.
 397          *
 398          * The ACPI 1.0 reserved fields that will be zeroed are the bytes located at
 399          * offset 45, 55, 95, and the word located at offset 109, 110.
 400          *
 401          * Note: The FADT revision value is unreliable. Only the length can be
 402          * trusted.
 403          */
 404         if (acpi_gbl_FADT.header.length <= ACPI_FADT_V2_SIZE) {
 405                 acpi_gbl_FADT.preferred_profile = 0;
 406                 acpi_gbl_FADT.pstate_control = 0;
 407                 acpi_gbl_FADT.cst_control = 0;
 408                 acpi_gbl_FADT.boot_flags = 0;
 409         }
 410
 411         /*
 412          * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"
 413          * generic address structures as necessary. Later code will always use
 414          * the 64-bit address structures.
 415          *
 416          * March 2009:
 417          * We now always use the 32-bit address if it is valid (non-null). This
 418          * is not in accordance with the ACPI specification which states that
 419          * the 64-bit address supersedes the 32-bit version, but we do this for
 420          * compatibility with other ACPI implementations. Most notably, in the
 421          * case where both the 32 and 64 versions are non-null, we use the 32-bit
 422          * version. This is the only address that is guaranteed to have been
 423          * tested by the BIOS manufacturer.
 424          */
 425         for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
 426                 address32 = *ACPI_ADD_PTR(u32,
 427                                           &acpi_gbl_FADT,
 428                                           fadt_info_table[i].address32);
 429
 430                 address64 = ACPI_ADD_PTR(struct acpi_generic_address,
 431                                          &acpi_gbl_FADT,
 432                                          fadt_info_table[i].address64);
 433
 434                 /*
 435                  * If both 32- and 64-bit addresses are valid (non-zero),
 436                  * they must match.
 437                  */
 438                 if (address64->address && address32 &&
 439                     (address64->address != (u64) address32)) {
 440                         ACPI_ERROR((AE_INFO,
 441                                     "32/64X address mismatch in %s: 0x%8.8X/0x%8.8X%8.8X, using 32",
 442                                     fadt_info_table[i].name, address32,
 443                                     ACPI_FORMAT_UINT64(address64->address)));
 444                 }
 445
 446                 /* Always use 32-bit address if it is valid (non-null) */
 447
 448                 if (address32) {
 449                         /*
 450                          * Copy the 32-bit address to the 64-bit GAS structure. The
 451                          * Space ID is always I/O for 32-bit legacy address fields
 452                         */
 453                         acpi_tb_init_generic_address(address64,
 454                                                      ACPI_ADR_SPACE_SYSTEM_IO,
 455                                                      *ACPI_ADD_PTR(u8,
 456                                                                    &acpi_gbl_FADT,
 457                                                                    fadt_info_table
 458                                                                    [i].length),
 459                                                      (u64) address32);
 460                 }
 461         }
 462 }
 463
 464 /*******************************************************************************
 465  *
 466  * FUNCTION:    acpi_tb_validate_fadt
 467  *
 468  * PARAMETERS:  Table           - Pointer to the FADT to be validated
 469  *
 470  * RETURN:      None
 471  *
 472  * DESCRIPTION: Validate various important fields within the FADT. If a problem
 473  *              is found, issue a message, but no status is returned.
 474  *              Used by both the table manager and the disassembler.
 475  *
 476  * Possible additional checks:
 477  * (acpi_gbl_FADT.pm1_event_length >= 4)
 478  * (acpi_gbl_FADT.pm1_control_length >= 2)
 479  * (acpi_gbl_FADT.pm_timer_length >= 4)
 480  * Gpe block lengths must be multiple of 2
 481  *
 482  ******************************************************************************/
 483
 484 static void acpi_tb_validate_fadt(void)
 485 {
 486         char *name;
 487         struct acpi_generic_address *address64;
 488         u8 length;
 489         u32 i;
 490
 491         /*
 492          * Check for FACS and DSDT address mismatches. An address mismatch between
 493          * the 32-bit and 64-bit address fields (FIRMWARE_CTRL/X_FIRMWARE_CTRL and
 494          * DSDT/X_DSDT) would indicate the presence of two FACS or two DSDT tables.
 495          */
 496         if (acpi_gbl_FADT.facs &&
 497             (acpi_gbl_FADT.Xfacs != (u64) acpi_gbl_FADT.facs)) {
 498                 ACPI_WARNING((AE_INFO,
 499                               "32/64X FACS address mismatch in FADT - "
 500                               "0x%8.8X/0x%8.8X%8.8X, using 32",
 501                               acpi_gbl_FADT.facs,
 502                               ACPI_FORMAT_UINT64(acpi_gbl_FADT.Xfacs)));
 503
 504                 acpi_gbl_FADT.Xfacs = (u64) acpi_gbl_FADT.facs;
 505         }
 506
 507         if (acpi_gbl_FADT.dsdt &&
 508             (acpi_gbl_FADT.Xdsdt != (u64) acpi_gbl_FADT.dsdt)) {
 509                 ACPI_WARNING((AE_INFO,
 510                               "32/64X DSDT address mismatch in FADT - "
 511                               "0x%8.8X/0x%8.8X%8.8X, using 32",
 512                               acpi_gbl_FADT.dsdt,
 513                               ACPI_FORMAT_UINT64(acpi_gbl_FADT.Xdsdt)));
 514
 515                 acpi_gbl_FADT.Xdsdt = (u64) acpi_gbl_FADT.dsdt;
 516         }
 517
 518         /* If Hardware Reduced flag is set, we are all done */
 519
 520         if (acpi_gbl_reduced_hardware) {
 521                 return;
 522         }
 523
 524         /* Examine all of the 64-bit extended address fields (X fields) */
 525
 526         for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
 527                 /*
 528                  * Generate pointer to the 64-bit address, get the register
 529                  * length (width) and the register name
 530                  */
 531                 address64 = ACPI_ADD_PTR(struct acpi_generic_address,
 532                                          &acpi_gbl_FADT,
 533                                          fadt_info_table[i].address64);
 534                 length =
 535                     *ACPI_ADD_PTR(u8, &acpi_gbl_FADT,
 536                                   fadt_info_table[i].length);
 537                 name = fadt_info_table[i].name;
 538
 539                 /*
 540                  * For each extended field, check for length mismatch between the
 541                  * legacy length field and the corresponding 64-bit X length field.
 542                  */
 543                 if (address64->address &&
 544                     (address64->bit_width != ACPI_MUL_8(length))) {
 545                         ACPI_WARNING((AE_INFO,
 546                                       "32/64X length mismatch in %s: %u/%u",
 547                                       name, ACPI_MUL_8(length),
 548                                       address64->bit_width));
 549                 }
 550
 551                 if (fadt_info_table[i].type & ACPI_FADT_REQUIRED) {
 552                         /*
 553                          * Field is required (Pm1a_event, Pm1a_control, pm_timer).
 554                          * Both the address and length must be non-zero.
 555                          */
 556                         if (!address64->address || !length) {
 557                                 ACPI_ERROR((AE_INFO,
 558                                             "Required field %s has zero address and/or length:"
 559                                             " 0x%8.8X%8.8X/0x%X",
 560                                             name,
 561                                             ACPI_FORMAT_UINT64(address64->
 562                                                                address),
 563                                             length));
 564                         }
 565                 } else if (fadt_info_table[i].type & ACPI_FADT_SEPARATE_LENGTH) {
 566                         /*
 567                          * Field is optional (PM2Control, GPE0, GPE1) AND has its own
 568                          * length field. If present, both the address and length must
 569                          * be valid.
 570                          */
 571                         if ((address64->address && !length) ||
 572                             (!address64->address && length)) {
 573                                 ACPI_WARNING((AE_INFO,
 574                                               "Optional field %s has zero address or length: "
 575                                               "0x%8.8X%8.8X/0x%X",
 576                                               name,
 577                                               ACPI_FORMAT_UINT64(address64->
 578                                                                  address),
 579                                               length));
 580                         }
 581                 }
 582         }
 583 }
 584
 585 /*******************************************************************************
 586  *
 587  * FUNCTION:    acpi_tb_setup_fadt_registers
 588  *
 589  * PARAMETERS:  None, uses acpi_gbl_FADT.
 590  *
 591  * RETURN:      None
 592  *
 593  * DESCRIPTION: Initialize global ACPI PM1 register definitions. Optionally,
 594  *              force FADT register definitions to their default lengths.
 595  *
 596  ******************************************************************************/
 597
 598 static void acpi_tb_setup_fadt_registers(void)
 599 {
 600         struct acpi_generic_address *target64;
 601         struct acpi_generic_address *source64;
 602         u8 pm1_register_byte_width;
 603         u32 i;
 604
 605         /*
 606          * Optionally check all register lengths against the default values and
 607          * update them if they are incorrect.
 608          */
 609         if (acpi_gbl_use_default_register_widths) {
 610                 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
 611                         target64 =
 612                             ACPI_ADD_PTR(struct acpi_generic_address,
 613                                          &acpi_gbl_FADT,
 614                                          fadt_info_table[i].address64);
 615
 616                         /*
 617                          * If a valid register (Address != 0) and the (default_length > 0)
 618                          * (Not a GPE register), then check the width against the default.
 619                          */
 620                         if ((target64->address) &&
 621                             (fadt_info_table[i].default_length > 0) &&
 622                             (fadt_info_table[i].default_length !=
 623                              target64->bit_width)) {
 624                                 ACPI_WARNING((AE_INFO,
 625                                               "Invalid length for %s: %u, using default %u",
 626                                               fadt_info_table[i].name,
 627                                               target64->bit_width,
 628                                               fadt_info_table[i].
 629                                               default_length));
 630
 631                                 /* Incorrect size, set width to the default */
 632
 633                                 target64->bit_width =
 634                                     fadt_info_table[i].default_length;
 635                         }
 636                 }
 637         }
 638
 639         /*
 640          * Get the length of the individual PM1 registers (enable and status).
 641          * Each register is defined to be (event block length / 2). Extra divide
 642          * by 8 converts bits to bytes.
 643          */
 644         pm1_register_byte_width = (u8)
 645             ACPI_DIV_16(acpi_gbl_FADT.xpm1a_event_block.bit_width);
 646
 647         /*
 648          * Calculate separate GAS structs for the PM1x (A/B) Status and Enable
 649          * registers. These addresses do not appear (directly) in the FADT, so it
 650          * is useful to pre-calculate them from the PM1 Event Block definitions.
 651          *
 652          * The PM event blocks are split into two register blocks, first is the
 653          * PM Status Register block, followed immediately by the PM Enable
 654          * Register block. Each is of length (pm1_event_length/2)
 655          *
 656          * Note: The PM1A event block is required by the ACPI specification.
 657          * However, the PM1B event block is optional and is rarely, if ever,
 658          * used.
 659          */
 660
 661         for (i = 0; i < ACPI_FADT_PM_INFO_ENTRIES; i++) {
 662                 source64 =
 663                     ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
 664                                  fadt_pm_info_table[i].source);
 665
 666                 if (source64->address) {
 667                         acpi_tb_init_generic_address(fadt_pm_info_table[i].
 668                                                      target, source64->space_id,
 669                                                      pm1_register_byte_width,
 670                                                      source64->address +
 671                                                      (fadt_pm_info_table[i].
 672                                                       register_num *
 673                                                       pm1_register_byte_width));
 674                 }
 675         }
 676 }