drivers/acpi/tables.c

   1 /*
   2  *  acpi_tables.c - ACPI Boot-Time Table Parsing
   3  *
   4  *  Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   5  *
   6  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  19  *
  20  */
  21
  22 /* Uncomment next line to get verbose printout */
  23 /* #define DEBUG */
  24 #define pr_fmt(fmt) "ACPI: " fmt
  25
  26 #include <linux/init.h>
  27 #include <linux/kernel.h>
  28 #include <linux/smp.h>
  29 #include <linux/string.h>
  30 #include <linux/types.h>
  31 #include <linux/irq.h>
  32 #include <linux/errno.h>
  33 #include <linux/acpi.h>
  34 #include <linux/bootmem.h>
  35 #include <linux/earlycpio.h>
  36 #include <linux/memblock.h>
  37 #include <linux/initrd.h>
  38 #include "internal.h"
  39
  40 #ifdef CONFIG_ACPI_CUSTOM_DSDT
  41 #include CONFIG_ACPI_CUSTOM_DSDT_FILE
  42 #endif
  43
  44 #define ACPI_MAX_TABLES         128
  45
  46 static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
  47 static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
  48
  49 static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
  50
  51 static int acpi_apic_instance __initdata;
  52
  53 /*
  54  * Disable table checksum verification for the early stage due to the size
  55  * limitation of the current x86 early mapping implementation.
  56  */
  57 static bool acpi_verify_table_checksum __initdata = false;
  58
  59 void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
  60 {
  61         if (!header)
  62                 return;
  63
  64         switch (header->type) {
  65
  66         case ACPI_MADT_TYPE_LOCAL_APIC:
  67                 {
  68                         struct acpi_madt_local_apic *p =
  69                             (struct acpi_madt_local_apic *)header;
  70                         pr_debug("LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
  71                                  p->processor_id, p->id,
  72                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
  73                 }
  74                 break;
  75
  76         case ACPI_MADT_TYPE_LOCAL_X2APIC:
  77                 {
  78                         struct acpi_madt_local_x2apic *p =
  79                             (struct acpi_madt_local_x2apic *)header;
  80                         pr_debug("X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
  81                                  p->local_apic_id, p->uid,
  82                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
  83                 }
  84                 break;
  85
  86         case ACPI_MADT_TYPE_IO_APIC:
  87                 {
  88                         struct acpi_madt_io_apic *p =
  89                             (struct acpi_madt_io_apic *)header;
  90                         pr_debug("IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
  91                                  p->id, p->address, p->global_irq_base);
  92                 }
  93                 break;
  94
  95         case ACPI_MADT_TYPE_INTERRUPT_OVERRIDE:
  96                 {
  97                         struct acpi_madt_interrupt_override *p =
  98                             (struct acpi_madt_interrupt_override *)header;
  99                         pr_info("INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
 100                                 p->bus, p->source_irq, p->global_irq,
 101                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
 102                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2]);
 103                         if (p->inti_flags  &
 104                             ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK))
 105                                 pr_info("INT_SRC_OVR unexpected reserved flags: 0x%x\n",
 106                                         p->inti_flags  &
 107                                         ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK));
 108                 }
 109                 break;
 110
 111         case ACPI_MADT_TYPE_NMI_SOURCE:
 112                 {
 113                         struct acpi_madt_nmi_source *p =
 114                             (struct acpi_madt_nmi_source *)header;
 115                         pr_info("NMI_SRC (%s %s global_irq %d)\n",
 116                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
 117                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
 118                                 p->global_irq);
 119                 }
 120                 break;
 121
 122         case ACPI_MADT_TYPE_LOCAL_APIC_NMI:
 123                 {
 124                         struct acpi_madt_local_apic_nmi *p =
 125                             (struct acpi_madt_local_apic_nmi *)header;
 126                         pr_info("LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
 127                                 p->processor_id,
 128                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK ],
 129                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
 130                                 p->lint);
 131                 }
 132                 break;
 133
 134         case ACPI_MADT_TYPE_LOCAL_X2APIC_NMI:
 135                 {
 136                         u16 polarity, trigger;
 137                         struct acpi_madt_local_x2apic_nmi *p =
 138                             (struct acpi_madt_local_x2apic_nmi *)header;
 139
 140                         polarity = p->inti_flags & ACPI_MADT_POLARITY_MASK;
 141                         trigger = (p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
 142
 143                         pr_info("X2APIC_NMI (uid[0x%02x] %s %s lint[0x%x])\n",
 144                                 p->uid,
 145                                 mps_inti_flags_polarity[polarity],
 146                                 mps_inti_flags_trigger[trigger],
 147                                 p->lint);
 148                 }
 149                 break;
 150
 151         case ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE:
 152                 {
 153                         struct acpi_madt_local_apic_override *p =
 154                             (struct acpi_madt_local_apic_override *)header;
 155                         pr_info("LAPIC_ADDR_OVR (address[%p])\n",
 156                                 (void *)(unsigned long)p->address);
 157                 }
 158                 break;
 159
 160         case ACPI_MADT_TYPE_IO_SAPIC:
 161                 {
 162                         struct acpi_madt_io_sapic *p =
 163                             (struct acpi_madt_io_sapic *)header;
 164                         pr_debug("IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
 165                                  p->id, (void *)(unsigned long)p->address,
 166                                  p->global_irq_base);
 167                 }
 168                 break;
 169
 170         case ACPI_MADT_TYPE_LOCAL_SAPIC:
 171                 {
 172                         struct acpi_madt_local_sapic *p =
 173                             (struct acpi_madt_local_sapic *)header;
 174                         pr_debug("LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
 175                                  p->processor_id, p->id, p->eid,
 176                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
 177                 }
 178                 break;
 179
 180         case ACPI_MADT_TYPE_INTERRUPT_SOURCE:
 181                 {
 182                         struct acpi_madt_interrupt_source *p =
 183                             (struct acpi_madt_interrupt_source *)header;
 184                         pr_info("PLAT_INT_SRC (%s %s type[0x%x] id[0x%04x] eid[0x%x] iosapic_vector[0x%x] global_irq[0x%x]\n",
 185                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
 186                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
 187                                 p->type, p->id, p->eid, p->io_sapic_vector,
 188                                 p->global_irq);
 189                 }
 190                 break;
 191
 192         case ACPI_MADT_TYPE_GENERIC_INTERRUPT:
 193                 {
 194                         struct acpi_madt_generic_interrupt *p =
 195                                 (struct acpi_madt_generic_interrupt *)header;
 196                         pr_debug("GICC (acpi_id[0x%04x] address[%llx] MPIDR[0x%llx] %s)\n",
 197                                  p->uid, p->base_address,
 198                                  p->arm_mpidr,
 199                                  (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
 200
 201                 }
 202                 break;
 203
 204         case ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR:
 205                 {
 206                         struct acpi_madt_generic_distributor *p =
 207                                 (struct acpi_madt_generic_distributor *)header;
 208                         pr_debug("GIC Distributor (gic_id[0x%04x] address[%llx] gsi_base[%d])\n",
 209                                  p->gic_id, p->base_address,
 210                                  p->global_irq_base);
 211                 }
 212                 break;
 213
 214         default:
 215                 pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
 216                         header->type);
 217                 break;
 218         }
 219 }
 220
 221 /**
 222  * acpi_parse_entries_array - for each proc_num find a suitable subtable
 223  *
 224  * @id: table id (for debugging purposes)
 225  * @table_size: single entry size
 226  * @table_header: where does the table start?
 227  * @proc: array of acpi_subtable_proc struct containing entry id
 228  *        and associated handler with it
 229  * @proc_num: how big proc is?
 230  * @max_entries: how many entries can we process?
 231  *
 232  * For each proc_num find a subtable with proc->id and run proc->handler
 233  * on it. Assumption is that there's only single handler for particular
 234  * entry id.
 235  *
 236  * On success returns sum of all matching entries for all proc handlers.
 237  * Otherwise, -ENODEV or -EINVAL is returned.
 238  */
 239 static int __init
 240 acpi_parse_entries_array(char *id, unsigned long table_size,
 241                 struct acpi_table_header *table_header,
 242                 struct acpi_subtable_proc *proc, int proc_num,
 243                 unsigned int max_entries)
 244 {
 245         struct acpi_subtable_header *entry;
 246         unsigned long table_end;
 247         int count = 0;
 248         int errs = 0;
 249         int i;
 250
 251         if (acpi_disabled)
 252                 return -ENODEV;
 253
 254         if (!id)
 255                 return -EINVAL;
 256
 257         if (!table_size)
 258                 return -EINVAL;
 259
 260         if (!table_header) {
 261                 pr_warn("%4.4s not present\n", id);
 262                 return -ENODEV;
 263         }
 264
 265         table_end = (unsigned long)table_header + table_header->length;
 266
 267         /* Parse all entries looking for a match. */
 268
 269         entry = (struct acpi_subtable_header *)
 270             ((unsigned long)table_header + table_size);
 271
 272         while (((unsigned long)entry) + sizeof(struct acpi_subtable_header) <
 273                table_end) {
 274                 if (max_entries && count >= max_entries)
 275                         break;
 276
 277                 for (i = 0; i < proc_num; i++) {
 278                         if (entry->type != proc[i].id)
 279                                 continue;
 280                         if (!proc[i].handler ||
 281                              (!errs && proc[i].handler(entry, table_end))) {
 282                                 errs++;
 283                                 continue;
 284                         }
 285
 286                         proc[i].count++;
 287                         break;
 288                 }
 289                 if (i != proc_num)
 290                         count++;
 291
 292                 /*
 293                  * If entry->length is 0, break from this loop to avoid
 294                  * infinite loop.
 295                  */
 296                 if (entry->length == 0) {
 297                         pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, proc->id);
 298                         return -EINVAL;
 299                 }
 300
 301                 entry = (struct acpi_subtable_header *)
 302                     ((unsigned long)entry + entry->length);
 303         }
 304
 305         if (max_entries && count > max_entries) {
 306                 pr_warn("[%4.4s:0x%02x] found the maximum %i entries\n",
 307                         id, proc->id, count);
 308         }
 309
 310         return errs ? -EINVAL : count;
 311 }
 312
 313 int __init
 314 acpi_table_parse_entries_array(char *id,
 315                          unsigned long table_size,
 316                          struct acpi_subtable_proc *proc, int proc_num,
 317                          unsigned int max_entries)
 318 {
 319         struct acpi_table_header *table_header = NULL;
 320         int count;
 321         u32 instance = 0;
 322
 323         if (acpi_disabled)
 324                 return -ENODEV;
 325
 326         if (!id)
 327                 return -EINVAL;
 328
 329         if (!strncmp(id, ACPI_SIG_MADT, 4))
 330                 instance = acpi_apic_instance;
 331
 332         acpi_get_table(id, instance, &table_header);
 333         if (!table_header) {
 334                 pr_warn("%4.4s not present\n", id);
 335                 return -ENODEV;
 336         }
 337
 338         count = acpi_parse_entries_array(id, table_size, table_header,
 339                         proc, proc_num, max_entries);
 340
 341         acpi_put_table(table_header);
 342         return count;
 343 }
 344
 345 int __init
 346 acpi_table_parse_entries(char *id,
 347                         unsigned long table_size,
 348                         int entry_id,
 349                         acpi_tbl_entry_handler handler,
 350                         unsigned int max_entries)
 351 {
 352         struct acpi_subtable_proc proc = {
 353                 .id             = entry_id,
 354                 .handler        = handler,
 355         };
 356
 357         return acpi_table_parse_entries_array(id, table_size, &proc, 1,
 358                                                 max_entries);
 359 }
 360
 361 int __init
 362 acpi_table_parse_madt(enum acpi_madt_type id,
 363                       acpi_tbl_entry_handler handler, unsigned int max_entries)
 364 {
 365         return acpi_table_parse_entries(ACPI_SIG_MADT,
 366                                             sizeof(struct acpi_table_madt), id,
 367                                             handler, max_entries);
 368 }
 369
 370 /**
 371  * acpi_table_parse - find table with @id, run @handler on it
 372  * @id: table id to find
 373  * @handler: handler to run
 374  *
 375  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
 376  * run @handler on it.
 377  *
 378  * Return 0 if table found, -errno if not.
 379  */
 380 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
 381 {
 382         struct acpi_table_header *table = NULL;
 383
 384         if (acpi_disabled)
 385                 return -ENODEV;
 386
 387         if (!id || !handler)
 388                 return -EINVAL;
 389
 390         if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
 391                 acpi_get_table(id, acpi_apic_instance, &table);
 392         else
 393                 acpi_get_table(id, 0, &table);
 394
 395         if (table) {
 396                 handler(table);
 397                 acpi_put_table(table);
 398                 return 0;
 399         } else
 400                 return -ENODEV;
 401 }
 402
 403 /*
 404  * The BIOS is supposed to supply a single APIC/MADT,
 405  * but some report two.  Provide a knob to use either.
 406  * (don't you wish instance 0 and 1 were not the same?)
 407  */
 408 static void __init check_multiple_madt(void)
 409 {
 410         struct acpi_table_header *table = NULL;
 411
 412         acpi_get_table(ACPI_SIG_MADT, 2, &table);
 413         if (table) {
 414                 pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
 415                         acpi_apic_instance);
 416                 pr_warn("If \"acpi_apic_instance=%d\" works better, "
 417                         "notify linux-acpi@vger.kernel.org\n",
 418                         acpi_apic_instance ? 0 : 2);
 419                 acpi_put_table(table);
 420
 421         } else
 422                 acpi_apic_instance = 0;
 423
 424         return;
 425 }
 426
 427 static void acpi_table_taint(struct acpi_table_header *table)
 428 {
 429         pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
 430                 table->signature, table->oem_table_id);
 431         add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
 432 }
 433
 434 #ifdef CONFIG_ACPI_TABLE_UPGRADE
 435 static u64 acpi_tables_addr;
 436 static int all_tables_size;
 437
 438 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
 439 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
 440 {
 441         u8 sum = 0;
 442         u8 *end = buffer + length;
 443
 444         while (buffer < end)
 445                 sum = (u8) (sum + *(buffer++));
 446         return sum;
 447 }
 448
 449 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
 450 static const char * const table_sigs[] = {
 451         ACPI_SIG_BERT, ACPI_SIG_CPEP, ACPI_SIG_ECDT, ACPI_SIG_EINJ,
 452         ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT, ACPI_SIG_MSCT,
 453         ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT, ACPI_SIG_ASF,
 454         ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR, ACPI_SIG_HPET,
 455         ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG, ACPI_SIG_MCHI,
 456         ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI, ACPI_SIG_TCPA,
 457         ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT, ACPI_SIG_WDDT,
 458         ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT, ACPI_SIG_PSDT,
 459         ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT, ACPI_SIG_IORT,
 460         NULL };
 461
 462 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
 463
 464 #define NR_ACPI_INITRD_TABLES 64
 465 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
 466 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
 467
 468 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
 469
 470 void __init acpi_table_upgrade(void)
 471 {
 472         void *data = (void *)initrd_start;
 473         size_t size = initrd_end - initrd_start;
 474         int sig, no, table_nr = 0, total_offset = 0;
 475         long offset = 0;
 476         struct acpi_table_header *table;
 477         char cpio_path[32] = "kernel/firmware/acpi/";
 478         struct cpio_data file;
 479
 480         if (data == NULL || size == 0)
 481                 return;
 482
 483         for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
 484                 file = find_cpio_data(cpio_path, data, size, &offset);
 485                 if (!file.data)
 486                         break;
 487
 488                 data += offset;
 489                 size -= offset;
 490
 491                 if (file.size < sizeof(struct acpi_table_header)) {
 492                         pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
 493                                 cpio_path, file.name);
 494                         continue;
 495                 }
 496
 497                 table = file.data;
 498
 499                 for (sig = 0; table_sigs[sig]; sig++)
 500                         if (!memcmp(table->signature, table_sigs[sig], 4))
 501                                 break;
 502
 503                 if (!table_sigs[sig]) {
 504                         pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
 505                                 cpio_path, file.name);
 506                         continue;
 507                 }
 508                 if (file.size != table->length) {
 509                         pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
 510                                 cpio_path, file.name);
 511                         continue;
 512                 }
 513                 if (acpi_table_checksum(file.data, table->length)) {
 514                         pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
 515                                 cpio_path, file.name);
 516                         continue;
 517                 }
 518
 519                 pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
 520                         table->signature, cpio_path, file.name, table->length);
 521
 522                 all_tables_size += table->length;
 523                 acpi_initrd_files[table_nr].data = file.data;
 524                 acpi_initrd_files[table_nr].size = file.size;
 525                 table_nr++;
 526         }
 527         if (table_nr == 0)
 528                 return;
 529
 530         acpi_tables_addr =
 531                 memblock_find_in_range(0, ACPI_TABLE_UPGRADE_MAX_PHYS,
 532                                        all_tables_size, PAGE_SIZE);
 533         if (!acpi_tables_addr) {
 534                 WARN_ON(1);
 535                 return;
 536         }
 537         /*
 538          * Only calling e820_add_reserve does not work and the
 539          * tables are invalid (memory got used) later.
 540          * memblock_reserve works as expected and the tables won't get modified.
 541          * But it's not enough on X86 because ioremap will
 542          * complain later (used by acpi_os_map_memory) that the pages
 543          * that should get mapped are not marked "reserved".
 544          * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
 545          * works fine.
 546          */
 547         memblock_reserve(acpi_tables_addr, all_tables_size);
 548         arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
 549
 550         /*
 551          * early_ioremap only can remap 256k one time. If we map all
 552          * tables one time, we will hit the limit. Need to map chunks
 553          * one by one during copying the same as that in relocate_initrd().
 554          */
 555         for (no = 0; no < table_nr; no++) {
 556                 unsigned char *src_p = acpi_initrd_files[no].data;
 557                 phys_addr_t size = acpi_initrd_files[no].size;
 558                 phys_addr_t dest_addr = acpi_tables_addr + total_offset;
 559                 phys_addr_t slop, clen;
 560                 char *dest_p;
 561
 562                 total_offset += size;
 563
 564                 while (size) {
 565                         slop = dest_addr & ~PAGE_MASK;
 566                         clen = size;
 567                         if (clen > MAP_CHUNK_SIZE - slop)
 568                                 clen = MAP_CHUNK_SIZE - slop;
 569                         dest_p = early_memremap(dest_addr & PAGE_MASK,
 570                                                 clen + slop);
 571                         memcpy(dest_p + slop, src_p, clen);
 572                         early_memunmap(dest_p, clen + slop);
 573                         src_p += clen;
 574                         dest_addr += clen;
 575                         size -= clen;
 576                 }
 577         }
 578 }
 579
 580 static acpi_status
 581 acpi_table_initrd_override(struct acpi_table_header *existing_table,
 582                            acpi_physical_address *address, u32 *length)
 583 {
 584         int table_offset = 0;
 585         int table_index = 0;
 586         struct acpi_table_header *table;
 587         u32 table_length;
 588
 589         *length = 0;
 590         *address = 0;
 591         if (!acpi_tables_addr)
 592                 return AE_OK;
 593
 594         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
 595                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
 596                                            ACPI_HEADER_SIZE);
 597                 if (table_offset + table->length > all_tables_size) {
 598                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 599                         WARN_ON(1);
 600                         return AE_OK;
 601                 }
 602
 603                 table_length = table->length;
 604
 605                 /* Only override tables matched */
 606                 if (memcmp(existing_table->signature, table->signature, 4) ||
 607                     memcmp(table->oem_id, existing_table->oem_id,
 608                            ACPI_OEM_ID_SIZE) ||
 609                     memcmp(table->oem_table_id, existing_table->oem_table_id,
 610                            ACPI_OEM_TABLE_ID_SIZE)) {
 611                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 612                         goto next_table;
 613                 }
 614                 /*
 615                  * Mark the table to avoid being used in
 616                  * acpi_table_initrd_scan() and check the revision.
 617                  */
 618                 if (test_and_set_bit(table_index, acpi_initrd_installed) ||
 619                     existing_table->oem_revision >= table->oem_revision) {
 620                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 621                         goto next_table;
 622                 }
 623
 624                 *length = table_length;
 625                 *address = acpi_tables_addr + table_offset;
 626                 pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
 627                         table->signature, table->oem_id,
 628                         table->oem_table_id);
 629                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 630                 break;
 631
 632 next_table:
 633                 table_offset += table_length;
 634                 table_index++;
 635         }
 636         return AE_OK;
 637 }
 638
 639 static void __init acpi_table_initrd_scan(void)
 640 {
 641         int table_offset = 0;
 642         int table_index = 0;
 643         u32 table_length;
 644         struct acpi_table_header *table;
 645
 646         if (!acpi_tables_addr)
 647                 return;
 648
 649         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
 650                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
 651                                            ACPI_HEADER_SIZE);
 652                 if (table_offset + table->length > all_tables_size) {
 653                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 654                         WARN_ON(1);
 655                         return;
 656                 }
 657
 658                 table_length = table->length;
 659
 660                 /* Skip RSDT/XSDT which should only be used for override */
 661                 if (ACPI_COMPARE_NAME(table->signature, ACPI_SIG_RSDT) ||
 662                     ACPI_COMPARE_NAME(table->signature, ACPI_SIG_XSDT)) {
 663                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 664                         goto next_table;
 665                 }
 666                 /*
 667                  * Mark the table to avoid being used in
 668                  * acpi_table_initrd_override(). Though this is not possible
 669                  * because override is disabled in acpi_install_table().
 670                  */
 671                 if (test_and_set_bit(table_index, acpi_initrd_installed)) {
 672                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 673                         goto next_table;
 674                 }
 675
 676                 pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
 677                         table->signature, table->oem_id,
 678                         table->oem_table_id);
 679                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 680                 acpi_install_table(acpi_tables_addr + table_offset, TRUE);
 681 next_table:
 682                 table_offset += table_length;
 683                 table_index++;
 684         }
 685 }
 686 #else
 687 static acpi_status
 688 acpi_table_initrd_override(struct acpi_table_header *existing_table,
 689                            acpi_physical_address *address,
 690                            u32 *table_length)
 691 {
 692         *table_length = 0;
 693         *address = 0;
 694         return AE_OK;
 695 }
 696
 697 static void __init acpi_table_initrd_scan(void)
 698 {
 699 }
 700 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
 701
 702 acpi_status
 703 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
 704                                 acpi_physical_address *address,
 705                                 u32 *table_length)
 706 {
 707         return acpi_table_initrd_override(existing_table, address,
 708                                           table_length);
 709 }
 710
 711 acpi_status
 712 acpi_os_table_override(struct acpi_table_header *existing_table,
 713                        struct acpi_table_header **new_table)
 714 {
 715         if (!existing_table || !new_table)
 716                 return AE_BAD_PARAMETER;
 717
 718         *new_table = NULL;
 719
 720 #ifdef CONFIG_ACPI_CUSTOM_DSDT
 721         if (strncmp(existing_table->signature, "DSDT", 4) == 0)
 722                 *new_table = (struct acpi_table_header *)AmlCode;
 723 #endif
 724         if (*new_table != NULL)
 725                 acpi_table_taint(existing_table);
 726         return AE_OK;
 727 }
 728
 729 /*
 730  * acpi_table_init()
 731  *
 732  * find RSDP, find and checksum SDT/XSDT.
 733  * checksum all tables, print SDT/XSDT
 734  *
 735  * result: sdt_entry[] is initialized
 736  */
 737
 738 int __init acpi_table_init(void)
 739 {
 740         acpi_status status;
 741
 742         if (acpi_verify_table_checksum) {
 743                 pr_info("Early table checksum verification enabled\n");
 744                 acpi_gbl_enable_table_validation = TRUE;
 745         } else {
 746                 pr_info("Early table checksum verification disabled\n");
 747                 acpi_gbl_enable_table_validation = FALSE;
 748         }
 749
 750         status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
 751         if (ACPI_FAILURE(status))
 752                 return -EINVAL;
 753         acpi_table_initrd_scan();
 754
 755         check_multiple_madt();
 756         return 0;
 757 }
 758
 759 static int __init acpi_parse_apic_instance(char *str)
 760 {
 761         if (!str)
 762                 return -EINVAL;
 763
 764         if (kstrtoint(str, 0, &acpi_apic_instance))
 765                 return -EINVAL;
 766
 767         pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
 768
 769         return 0;
 770 }
 771
 772 early_param("acpi_apic_instance", acpi_parse_apic_instance);
 773
 774 static int __init acpi_force_table_verification_setup(char *s)
 775 {
 776         acpi_verify_table_checksum = true;
 777
 778         return 0;
 779 }
 780
 781 early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
 782
 783 static int __init acpi_force_32bit_fadt_addr(char *s)
 784 {
 785         pr_info("Forcing 32 Bit FADT addresses\n");
 786         acpi_gbl_use32_bit_fadt_addresses = TRUE;
 787
 788         return 0;
 789 }
 790
 791 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);