Pileus Git - ~andy/linux/blob - drivers/acpi/acpica/tbfadt.c

   1 /******************************************************************************
   2  *
   3  * Module Name: tbfadt   - FADT table utilities
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2013, 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 void
  53 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
  54                              u8 space_id,
  55                              u8 byte_width, u64 address, char *register_name);
  56
  57 static void acpi_tb_convert_fadt(void);
  58
  59 static void acpi_tb_setup_fadt_registers(void);
  60
  61 static u64
  62 acpi_tb_select_address(char *register_name, u32 address32, u64 address64);
  63
  64 /* Table for conversion of FADT to common internal format and FADT validation */
  65
  66 typedef struct acpi_fadt_info {
  67         char *name;
  68         u16 address64;
  69         u16 address32;
  70         u16 length;
  71         u8 default_length;
  72         u8 type;
  73
  74 } acpi_fadt_info;
  75
  76 #define ACPI_FADT_OPTIONAL          0
  77 #define ACPI_FADT_REQUIRED          1
  78 #define ACPI_FADT_SEPARATE_LENGTH   2
  79
  80 static struct acpi_fadt_info fadt_info_table[] = {
  81         {"Pm1aEventBlock",
  82          ACPI_FADT_OFFSET(xpm1a_event_block),
  83          ACPI_FADT_OFFSET(pm1a_event_block),
  84          ACPI_FADT_OFFSET(pm1_event_length),
  85          ACPI_PM1_REGISTER_WIDTH * 2,   /* Enable + Status register */
  86          ACPI_FADT_REQUIRED},
  87
  88         {"Pm1bEventBlock",
  89          ACPI_FADT_OFFSET(xpm1b_event_block),
  90          ACPI_FADT_OFFSET(pm1b_event_block),
  91          ACPI_FADT_OFFSET(pm1_event_length),
  92          ACPI_PM1_REGISTER_WIDTH * 2,   /* Enable + Status register */
  93          ACPI_FADT_OPTIONAL},
  94
  95         {"Pm1aControlBlock",
  96          ACPI_FADT_OFFSET(xpm1a_control_block),
  97          ACPI_FADT_OFFSET(pm1a_control_block),
  98          ACPI_FADT_OFFSET(pm1_control_length),
  99          ACPI_PM1_REGISTER_WIDTH,
 100          ACPI_FADT_REQUIRED},
 101
 102         {"Pm1bControlBlock",
 103          ACPI_FADT_OFFSET(xpm1b_control_block),
 104          ACPI_FADT_OFFSET(pm1b_control_block),
 105          ACPI_FADT_OFFSET(pm1_control_length),
 106          ACPI_PM1_REGISTER_WIDTH,
 107          ACPI_FADT_OPTIONAL},
 108
 109         {"Pm2ControlBlock",
 110          ACPI_FADT_OFFSET(xpm2_control_block),
 111          ACPI_FADT_OFFSET(pm2_control_block),
 112          ACPI_FADT_OFFSET(pm2_control_length),
 113          ACPI_PM2_REGISTER_WIDTH,
 114          ACPI_FADT_SEPARATE_LENGTH},
 115
 116         {"PmTimerBlock",
 117          ACPI_FADT_OFFSET(xpm_timer_block),
 118          ACPI_FADT_OFFSET(pm_timer_block),
 119          ACPI_FADT_OFFSET(pm_timer_length),
 120          ACPI_PM_TIMER_WIDTH,
 121          ACPI_FADT_SEPARATE_LENGTH},    /* ACPI 5.0A: Timer is optional */
 122
 123         {"Gpe0Block",
 124          ACPI_FADT_OFFSET(xgpe0_block),
 125          ACPI_FADT_OFFSET(gpe0_block),
 126          ACPI_FADT_OFFSET(gpe0_block_length),
 127          0,
 128          ACPI_FADT_SEPARATE_LENGTH},
 129
 130         {"Gpe1Block",
 131          ACPI_FADT_OFFSET(xgpe1_block),
 132          ACPI_FADT_OFFSET(gpe1_block),
 133          ACPI_FADT_OFFSET(gpe1_block_length),
 134          0,
 135          ACPI_FADT_SEPARATE_LENGTH}
 136 };
 137
 138 #define ACPI_FADT_INFO_ENTRIES \
 139                         (sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info))
 140
 141 /* Table used to split Event Blocks into separate status/enable registers */
 142
 143 typedef struct acpi_fadt_pm_info {
 144         struct acpi_generic_address *target;
 145         u16 source;
 146         u8 register_num;
 147
 148 } acpi_fadt_pm_info;
 149
 150 static struct acpi_fadt_pm_info fadt_pm_info_table[] = {
 151         {&acpi_gbl_xpm1a_status,
 152          ACPI_FADT_OFFSET(xpm1a_event_block),
 153          0},
 154
 155         {&acpi_gbl_xpm1a_enable,
 156          ACPI_FADT_OFFSET(xpm1a_event_block),
 157          1},
 158
 159         {&acpi_gbl_xpm1b_status,
 160          ACPI_FADT_OFFSET(xpm1b_event_block),
 161          0},
 162
 163         {&acpi_gbl_xpm1b_enable,
 164          ACPI_FADT_OFFSET(xpm1b_event_block),
 165          1}
 166 };
 167
 168 #define ACPI_FADT_PM_INFO_ENTRIES \
 169                         (sizeof (fadt_pm_info_table) / sizeof (struct acpi_fadt_pm_info))
 170
 171 /*******************************************************************************
 172  *
 173  * FUNCTION:    acpi_tb_init_generic_address
 174  *
 175  * PARAMETERS:  generic_address     - GAS struct to be initialized
 176  *              space_id            - ACPI Space ID for this register
 177  *              byte_width          - Width of this register
 178  *              address             - Address of the register
 179  *              register_name       - ASCII name of the ACPI register
 180  *
 181  * RETURN:      None
 182  *
 183  * DESCRIPTION: Initialize a Generic Address Structure (GAS)
 184  *              See the ACPI specification for a full description and
 185  *              definition of this structure.
 186  *
 187  ******************************************************************************/
 188
 189 static void
 190 acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,
 191                              u8 space_id,
 192                              u8 byte_width, u64 address, char *register_name)
 193 {
 194         u8 bit_width;
 195
 196         /* Bit width field in the GAS is only one byte long, 255 max */
 197
 198         bit_width = (u8)(byte_width * 8);
 199
 200         if (byte_width > 31) {  /* (31*8)=248 */
 201                 ACPI_ERROR((AE_INFO,
 202                             "%s - 32-bit FADT register is too long (%u bytes, %u bits) "
 203                             "to convert to GAS struct - 255 bits max, truncating",
 204                             register_name, byte_width, (byte_width * 8)));
 205
 206                 bit_width = 255;
 207         }
 208
 209         /*
 210          * The 64-bit Address field is non-aligned in the byte packed
 211          * GAS struct.
 212          */
 213         ACPI_MOVE_64_TO_64(&generic_address->address, &address);
 214
 215         /* All other fields are byte-wide */
 216
 217         generic_address->space_id = space_id;
 218         generic_address->bit_width = bit_width;
 219         generic_address->bit_offset = 0;
 220         generic_address->access_width = 0;      /* Access width ANY */
 221 }
 222
 223 /*******************************************************************************
 224  *
 225  * FUNCTION:    acpi_tb_select_address
 226  *
 227  * PARAMETERS:  register_name       - ASCII name of the ACPI register
 228  *              address32           - 32-bit address of the register
 229  *              address64           - 64-bit address of the register
 230  *
 231  * RETURN:      The resolved 64-bit address
 232  *
 233  * DESCRIPTION: Select between 32-bit and 64-bit versions of addresses within
 234  *              the FADT. Used for the FACS and DSDT addresses.
 235  *
 236  * NOTES:
 237  *
 238  * Check for FACS and DSDT address mismatches. An address mismatch between
 239  * the 32-bit and 64-bit address fields (FIRMWARE_CTRL/X_FIRMWARE_CTRL and
 240  * DSDT/X_DSDT) could be a corrupted address field or it might indicate
 241  * the presence of two FACS or two DSDT tables.
 242  *
 243  * November 2013:
 244  * By default, as per the ACPICA specification, a valid 64-bit address is
 245  * used regardless of the value of the 32-bit address. However, this
 246  * behavior can be overridden via the acpi_gbl_use32_bit_fadt_addresses flag.
 247  *
 248  ******************************************************************************/
 249
 250 static u64
 251 acpi_tb_select_address(char *register_name, u32 address32, u64 address64)
 252 {
 253
 254         if (!address64) {
 255
 256                 /* 64-bit address is zero, use 32-bit address */
 257
 258                 return ((u64)address32);
 259         }
 260
 261         if (address32 && (address64 != (u64)address32)) {
 262
 263                 /* Address mismatch between 32-bit and 64-bit versions */
 264
 265                 ACPI_BIOS_WARNING((AE_INFO,
 266                                    "32/64X %s address mismatch in FADT: "
 267                                    "0x%8.8X/0x%8.8X%8.8X, using %u-bit address",
 268                                    register_name, address32,
 269                                    ACPI_FORMAT_UINT64(address64),
 270                                    acpi_gbl_use32_bit_fadt_addresses ? 32 :
 271                                    64));
 272
 273                 /* 32-bit address override */
 274
 275                 if (acpi_gbl_use32_bit_fadt_addresses) {
 276                         return ((u64)address32);
 277                 }
 278         }
 279
 280         /* Default is to use the 64-bit address */
 281
 282         return (address64);
 283 }
 284
 285 /*******************************************************************************
 286  *
 287  * FUNCTION:    acpi_tb_parse_fadt
 288  *
 289  * PARAMETERS:  table_index         - Index for the FADT
 290  *
 291  * RETURN:      None
 292  *
 293  * DESCRIPTION: Initialize the FADT, DSDT and FACS tables
 294  *              (FADT contains the addresses of the DSDT and FACS)
 295  *
 296  ******************************************************************************/
 297
 298 void acpi_tb_parse_fadt(u32 table_index)
 299 {
 300         u32 length;
 301         struct acpi_table_header *table;
 302
 303         /*
 304          * The FADT has multiple versions with different lengths,
 305          * and it contains pointers to both the DSDT and FACS tables.
 306          *
 307          * Get a local copy of the FADT and convert it to a common format
 308          * Map entire FADT, assumed to be smaller than one page.
 309          */
 310         length = acpi_gbl_root_table_list.tables[table_index].length;
 311
 312         table =
 313             acpi_os_map_memory(acpi_gbl_root_table_list.tables[table_index].
 314                                address, length);
 315         if (!table) {
 316                 return;
 317         }
 318
 319         /*
 320          * Validate the FADT checksum before we copy the table. Ignore
 321          * checksum error as we want to try to get the DSDT and FACS.
 322          */
 323         (void)acpi_tb_verify_checksum(table, length);
 324
 325         /* Create a local copy of the FADT in common ACPI 2.0+ format */
 326
 327         acpi_tb_create_local_fadt(table, length);
 328
 329         /* All done with the real FADT, unmap it */
 330
 331         acpi_os_unmap_memory(table, length);
 332
 333         /* Obtain the DSDT and FACS tables via their addresses within the FADT */
 334
 335         acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.Xdsdt,
 336                               ACPI_SIG_DSDT, ACPI_TABLE_INDEX_DSDT);
 337
 338         /* If Hardware Reduced flag is set, there is no FACS */
 339
 340         if (!acpi_gbl_reduced_hardware) {
 341                 acpi_tb_install_table((acpi_physical_address) acpi_gbl_FADT.
 342                                       Xfacs, ACPI_SIG_FACS,
 343                                       ACPI_TABLE_INDEX_FACS);
 344         }
 345 }
 346
 347 /*******************************************************************************
 348  *
 349  * FUNCTION:    acpi_tb_create_local_fadt
 350  *
 351  * PARAMETERS:  table               - Pointer to BIOS FADT
 352  *              length              - Length of the table
 353  *
 354  * RETURN:      None
 355  *
 356  * DESCRIPTION: Get a local copy of the FADT and convert it to a common format.
 357  *              Performs validation on some important FADT fields.
 358  *
 359  * NOTE:        We create a local copy of the FADT regardless of the version.
 360  *
 361  ******************************************************************************/
 362
 363 void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
 364 {
 365         /*
 366          * Check if the FADT is larger than the largest table that we expect
 367          * (the ACPI 5.0 version). If so, truncate the table, and issue
 368          * a warning.
 369          */
 370         if (length > sizeof(struct acpi_table_fadt)) {
 371                 ACPI_BIOS_WARNING((AE_INFO,
 372                                    "FADT (revision %u) is longer than ACPI 5.0 version, "
 373                                    "truncating length %u to %u",
 374                                    table->revision, length,
 375                                    (u32)sizeof(struct acpi_table_fadt)));
 376         }
 377
 378         /* Clear the entire local FADT */
 379
 380         ACPI_MEMSET(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));
 381
 382         /* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */
 383
 384         ACPI_MEMCPY(&acpi_gbl_FADT, table,
 385                     ACPI_MIN(length, sizeof(struct acpi_table_fadt)));
 386
 387         /* Take a copy of the Hardware Reduced flag */
 388
 389         acpi_gbl_reduced_hardware = FALSE;
 390         if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) {
 391                 acpi_gbl_reduced_hardware = TRUE;
 392         }
 393
 394         /* Convert the local copy of the FADT to the common internal format */
 395
 396         acpi_tb_convert_fadt();
 397
 398         /* Initialize the global ACPI register structures */
 399
 400         acpi_tb_setup_fadt_registers();
 401 }
 402
 403 /*******************************************************************************
 404  *
 405  * FUNCTION:    acpi_tb_convert_fadt
 406  *
 407  * PARAMETERS:  none - acpi_gbl_FADT is used.
 408  *
 409  * RETURN:      None
 410  *
 411  * DESCRIPTION: Converts all versions of the FADT to a common internal format.
 412  *              Expand 32-bit addresses to 64-bit as necessary. Also validate
 413  *              important fields within the FADT.
 414  *
 415  * NOTE:        acpi_gbl_FADT must be of size (struct acpi_table_fadt), and must
 416  *              contain a copy of the actual BIOS-provided FADT.
 417  *
 418  * Notes on 64-bit register addresses:
 419  *
 420  * After this FADT conversion, later ACPICA code will only use the 64-bit "X"
 421  * fields of the FADT for all ACPI register addresses.
 422  *
 423  * The 64-bit X fields are optional extensions to the original 32-bit FADT
 424  * V1.0 fields. Even if they are present in the FADT, they are optional and
 425  * are unused if the BIOS sets them to zero. Therefore, we must copy/expand
 426  * 32-bit V1.0 fields to the 64-bit X fields if the the 64-bit X field is
 427  * originally zero.
 428  *
 429  * For ACPI 1.0 FADTs (that contain no 64-bit addresses), all 32-bit address
 430  * fields are expanded to the corresponding 64-bit X fields in the internal
 431  * common FADT.
 432  *
 433  * For ACPI 2.0+ FADTs, all valid (non-zero) 32-bit address fields are expanded
 434  * to the corresponding 64-bit X fields, if the 64-bit field is originally
 435  * zero. Adhering to the ACPI specification, we completely ignore the 32-bit
 436  * field if the 64-bit field is valid, regardless of whether the host OS is
 437  * 32-bit or 64-bit.
 438  *
 439  * Possible additional checks:
 440  *  (acpi_gbl_FADT.pm1_event_length >= 4)
 441  *  (acpi_gbl_FADT.pm1_control_length >= 2)
 442  *  (acpi_gbl_FADT.pm_timer_length >= 4)
 443  *  Gpe block lengths must be multiple of 2
 444  *
 445  ******************************************************************************/
 446
 447 static void acpi_tb_convert_fadt(void)
 448 {
 449         char *name;
 450         struct acpi_generic_address *address64;
 451         u32 address32;
 452         u8 length;
 453         u32 i;
 454
 455         /*
 456          * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which
 457          * should be zero are indeed zero. This will workaround BIOSs that
 458          * inadvertently place values in these fields.
 459          *
 460          * The ACPI 1.0 reserved fields that will be zeroed are the bytes located
 461          * at offset 45, 55, 95, and the word located at offset 109, 110.
 462          *
 463          * Note: The FADT revision value is unreliable. Only the length can be
 464          * trusted.
 465          */
 466         if (acpi_gbl_FADT.header.length <= ACPI_FADT_V2_SIZE) {
 467                 acpi_gbl_FADT.preferred_profile = 0;
 468                 acpi_gbl_FADT.pstate_control = 0;
 469                 acpi_gbl_FADT.cst_control = 0;
 470                 acpi_gbl_FADT.boot_flags = 0;
 471         }
 472
 473         /*
 474          * Now we can update the local FADT length to the length of the
 475          * current FADT version as defined by the ACPI specification.
 476          * Thus, we will have a common FADT internally.
 477          */
 478         acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt);
 479
 480         /*
 481          * Expand the 32-bit FACS and DSDT addresses to 64-bit as necessary.
 482          * Later ACPICA code will always use the X 64-bit field.
 483          */
 484         acpi_gbl_FADT.Xfacs = acpi_tb_select_address("FACS",
 485                                                      acpi_gbl_FADT.facs,
 486                                                      acpi_gbl_FADT.Xfacs);
 487
 488         acpi_gbl_FADT.Xdsdt = acpi_tb_select_address("DSDT",
 489                                                      acpi_gbl_FADT.dsdt,
 490                                                      acpi_gbl_FADT.Xdsdt);
 491
 492         /* If Hardware Reduced flag is set, we are all done */
 493
 494         if (acpi_gbl_reduced_hardware) {
 495                 return;
 496         }
 497
 498         /* Examine all of the 64-bit extended address fields (X fields) */
 499
 500         for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
 501                 /*
 502                  * Get the 32-bit and 64-bit addresses, as well as the register
 503                  * length and register name.
 504                  */
 505                 address32 = *ACPI_ADD_PTR(u32,
 506                                           &acpi_gbl_FADT,
 507                                           fadt_info_table[i].address32);
 508
 509                 address64 = ACPI_ADD_PTR(struct acpi_generic_address,
 510                                          &acpi_gbl_FADT,
 511                                          fadt_info_table[i].address64);
 512
 513                 length = *ACPI_ADD_PTR(u8,
 514                                        &acpi_gbl_FADT,
 515                                        fadt_info_table[i].length);
 516
 517                 name = fadt_info_table[i].name;
 518
 519                 /*
 520                  * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"
 521                  * generic address structures as necessary. Later code will always use
 522                  * the 64-bit address structures.
 523                  *
 524                  * November 2013:
 525                  * Now always use the 64-bit address if it is valid (non-zero), in
 526                  * accordance with the ACPI specification which states that a 64-bit
 527                  * address supersedes the 32-bit version. This behavior can be
 528                  * overridden by the acpi_gbl_use32_bit_fadt_addresses flag.
 529                  *
 530                  * During 64-bit address construction and verification,
 531                  * these cases are handled:
 532                  *
 533                  * Address32 zero, Address64 [don't care]   - Use Address64
 534                  *
 535                  * Address32 non-zero, Address64 zero       - Copy/use Address32
 536                  * Address32 non-zero == Address64 non-zero - Use Address64
 537                  * Address32 non-zero != Address64 non-zero - Warning, use Address64
 538                  *
 539                  * Override: if acpi_gbl_use32_bit_fadt_addresses is TRUE, and:
 540                  * Address32 non-zero != Address64 non-zero - Warning, copy/use Address32
 541                  *
 542                  * Note: space_id is always I/O for 32-bit legacy address fields
 543                  */
 544                 if (address32) {
 545                         if (!address64->address) {
 546
 547                                 /* 64-bit address is zero, use 32-bit address */
 548
 549                                 acpi_tb_init_generic_address(address64,
 550                                                              ACPI_ADR_SPACE_SYSTEM_IO,
 551                                                              *ACPI_ADD_PTR(u8,
 552                                                                            &acpi_gbl_FADT,
 553                                                                            fadt_info_table
 554                                                                            [i].
 555                                                                            length),
 556                                                              (u64)address32,
 557                                                              name);
 558                         } else if (address64->address != (u64)address32) {
 559
 560                                 /* Address mismatch */
 561
 562                                 ACPI_BIOS_WARNING((AE_INFO,
 563                                                    "32/64X address mismatch in FADT/%s: "
 564                                                    "0x%8.8X/0x%8.8X%8.8X, using %u-bit address",
 565                                                    name, address32,
 566                                                    ACPI_FORMAT_UINT64
 567                                                    (address64->address),
 568                                                    acpi_gbl_use32_bit_fadt_addresses
 569                                                    ? 32 : 64));
 570
 571                                 if (acpi_gbl_use32_bit_fadt_addresses) {
 572
 573                                         /* 32-bit address override */
 574
 575                                         acpi_tb_init_generic_address(address64,
 576                                                                      ACPI_ADR_SPACE_SYSTEM_IO,
 577                                                                      *ACPI_ADD_PTR
 578                                                                      (u8,
 579                                                                       &acpi_gbl_FADT,
 580                                                                       fadt_info_table
 581                                                                       [i].
 582                                                                       length),
 583                                                                      (u64)
 584                                                                      address32,
 585                                                                      name);
 586                                 }
 587                         }
 588                 }
 589
 590                 /*
 591                  * For each extended field, check for length mismatch between the
 592                  * legacy length field and the corresponding 64-bit X length field.
 593                  * Note: If the legacy length field is > 0xFF bits, ignore this
 594                  * check. (GPE registers can be larger than the 64-bit GAS structure
 595                  * can accomodate, 0xFF bits).
 596                  */
 597                 if (address64->address &&
 598                     (ACPI_MUL_8(length) <= ACPI_UINT8_MAX) &&
 599                     (address64->bit_width != ACPI_MUL_8(length))) {
 600                         ACPI_BIOS_WARNING((AE_INFO,
 601                                            "32/64X length mismatch in FADT/%s: %u/%u",
 602                                            name, ACPI_MUL_8(length),
 603                                            address64->bit_width));
 604                 }
 605
 606                 if (fadt_info_table[i].type & ACPI_FADT_REQUIRED) {
 607                         /*
 608                          * Field is required (Pm1a_event, Pm1a_control).
 609                          * Both the address and length must be non-zero.
 610                          */
 611                         if (!address64->address || !length) {
 612                                 ACPI_BIOS_ERROR((AE_INFO,
 613                                                  "Required FADT field %s has zero address and/or length: "
 614                                                  "0x%8.8X%8.8X/0x%X",
 615                                                  name,
 616                                                  ACPI_FORMAT_UINT64(address64->
 617                                                                     address),
 618                                                  length));
 619                         }
 620                 } else if (fadt_info_table[i].type & ACPI_FADT_SEPARATE_LENGTH) {
 621                         /*
 622                          * Field is optional (Pm2_control, GPE0, GPE1) AND has its own
 623                          * length field. If present, both the address and length must
 624                          * be valid.
 625                          */
 626                         if ((address64->address && !length) ||
 627                             (!address64->address && length)) {
 628                                 ACPI_BIOS_WARNING((AE_INFO,
 629                                                    "Optional FADT field %s has zero address or length: "
 630                                                    "0x%8.8X%8.8X/0x%X",
 631                                                    name,
 632                                                    ACPI_FORMAT_UINT64
 633                                                    (address64->address),
 634                                                    length));
 635                         }
 636                 }
 637         }
 638 }
 639
 640 /*******************************************************************************
 641  *
 642  * FUNCTION:    acpi_tb_setup_fadt_registers
 643  *
 644  * PARAMETERS:  None, uses acpi_gbl_FADT.
 645  *
 646  * RETURN:      None
 647  *
 648  * DESCRIPTION: Initialize global ACPI PM1 register definitions. Optionally,
 649  *              force FADT register definitions to their default lengths.
 650  *
 651  ******************************************************************************/
 652
 653 static void acpi_tb_setup_fadt_registers(void)
 654 {
 655         struct acpi_generic_address *target64;
 656         struct acpi_generic_address *source64;
 657         u8 pm1_register_byte_width;
 658         u32 i;
 659
 660         /*
 661          * Optionally check all register lengths against the default values and
 662          * update them if they are incorrect.
 663          */
 664         if (acpi_gbl_use_default_register_widths) {
 665                 for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
 666                         target64 =
 667                             ACPI_ADD_PTR(struct acpi_generic_address,
 668                                          &acpi_gbl_FADT,
 669                                          fadt_info_table[i].address64);
 670
 671                         /*
 672                          * If a valid register (Address != 0) and the (default_length > 0)
 673                          * (Not a GPE register), then check the width against the default.
 674                          */
 675                         if ((target64->address) &&
 676                             (fadt_info_table[i].default_length > 0) &&
 677                             (fadt_info_table[i].default_length !=
 678                              target64->bit_width)) {
 679                                 ACPI_BIOS_WARNING((AE_INFO,
 680                                                    "Invalid length for FADT/%s: %u, using default %u",
 681                                                    fadt_info_table[i].name,
 682                                                    target64->bit_width,
 683                                                    fadt_info_table[i].
 684                                                    default_length));
 685
 686                                 /* Incorrect size, set width to the default */
 687
 688                                 target64->bit_width =
 689                                     fadt_info_table[i].default_length;
 690                         }
 691                 }
 692         }
 693
 694         /*
 695          * Get the length of the individual PM1 registers (enable and status).
 696          * Each register is defined to be (event block length / 2). Extra divide
 697          * by 8 converts bits to bytes.
 698          */
 699         pm1_register_byte_width = (u8)
 700             ACPI_DIV_16(acpi_gbl_FADT.xpm1a_event_block.bit_width);
 701
 702         /*
 703          * Calculate separate GAS structs for the PM1x (A/B) Status and Enable
 704          * registers. These addresses do not appear (directly) in the FADT, so it
 705          * is useful to pre-calculate them from the PM1 Event Block definitions.
 706          *
 707          * The PM event blocks are split into two register blocks, first is the
 708          * PM Status Register block, followed immediately by the PM Enable
 709          * Register block. Each is of length (pm1_event_length/2)
 710          *
 711          * Note: The PM1A event block is required by the ACPI specification.
 712          * However, the PM1B event block is optional and is rarely, if ever,
 713          * used.
 714          */
 715
 716         for (i = 0; i < ACPI_FADT_PM_INFO_ENTRIES; i++) {
 717                 source64 =
 718                     ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
 719                                  fadt_pm_info_table[i].source);
 720
 721                 if (source64->address) {
 722                         acpi_tb_init_generic_address(fadt_pm_info_table[i].
 723                                                      target, source64->space_id,
 724                                                      pm1_register_byte_width,
 725                                                      source64->address +
 726                                                      (fadt_pm_info_table[i].
 727                                                       register_num *
 728                                                       pm1_register_byte_width),
 729                                                      "PmRegisters");
 730                 }
 731         }
 732 }