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: size of the root table
 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  * The table_size is not the size of the complete ACPI table (the length
 237  * field in the header struct), but only the size of the root table; i.e.,
 238  * the offset from the very first byte of the complete ACPI table, to the
 239  * first byte of the very first subtable.
 240  *
 241  * On success returns sum of all matching entries for all proc handlers.
 242  * Otherwise, -ENODEV or -EINVAL is returned.
 243  */
 244 static int __init
 245 acpi_parse_entries_array(char *id, unsigned long table_size,
 246                 struct acpi_table_header *table_header,
 247                 struct acpi_subtable_proc *proc, int proc_num,
 248                 unsigned int max_entries)
 249 {
 250         struct acpi_subtable_header *entry;
 251         unsigned long table_end;
 252         int count = 0;
 253         int errs = 0;
 254         int i;
 255
 256         if (acpi_disabled)
 257                 return -ENODEV;
 258
 259         if (!id)
 260                 return -EINVAL;
 261
 262         if (!table_size)
 263                 return -EINVAL;
 264
 265         if (!table_header) {
 266                 pr_warn("%4.4s not present\n", id);
 267                 return -ENODEV;
 268         }
 269
 270         table_end = (unsigned long)table_header + table_header->length;
 271
 272         /* Parse all entries looking for a match. */
 273
 274         entry = (struct acpi_subtable_header *)
 275             ((unsigned long)table_header + table_size);
 276
 277         while (((unsigned long)entry) + sizeof(struct acpi_subtable_header) <
 278                table_end) {
 279                 if (max_entries && count >= max_entries)
 280                         break;
 281
 282                 for (i = 0; i < proc_num; i++) {
 283                         if (entry->type != proc[i].id)
 284                                 continue;
 285                         if (!proc[i].handler ||
 286                              (!errs && proc[i].handler(entry, table_end))) {
 287                                 errs++;
 288                                 continue;
 289                         }
 290
 291                         proc[i].count++;
 292                         break;
 293                 }
 294                 if (i != proc_num)
 295                         count++;
 296
 297                 /*
 298                  * If entry->length is 0, break from this loop to avoid
 299                  * infinite loop.
 300                  */
 301                 if (entry->length == 0) {
 302                         pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, proc->id);
 303                         return -EINVAL;
 304                 }
 305
 306                 entry = (struct acpi_subtable_header *)
 307                     ((unsigned long)entry + entry->length);
 308         }
 309
 310         if (max_entries && count > max_entries) {
 311                 pr_warn("[%4.4s:0x%02x] found the maximum %i entries\n",
 312                         id, proc->id, count);
 313         }
 314
 315         return errs ? -EINVAL : count;
 316 }
 317
 318 int __init
 319 acpi_table_parse_entries_array(char *id,
 320                          unsigned long table_size,
 321                          struct acpi_subtable_proc *proc, int proc_num,
 322                          unsigned int max_entries)
 323 {
 324         struct acpi_table_header *table_header = NULL;
 325         int count;
 326         u32 instance = 0;
 327
 328         if (acpi_disabled)
 329                 return -ENODEV;
 330
 331         if (!id)
 332                 return -EINVAL;
 333
 334         if (!strncmp(id, ACPI_SIG_MADT, 4))
 335                 instance = acpi_apic_instance;
 336
 337         acpi_get_table(id, instance, &table_header);
 338         if (!table_header) {
 339                 pr_warn("%4.4s not present\n", id);
 340                 return -ENODEV;
 341         }
 342
 343         count = acpi_parse_entries_array(id, table_size, table_header,
 344                         proc, proc_num, max_entries);
 345
 346         acpi_put_table(table_header);
 347         return count;
 348 }
 349
 350 int __init
 351 acpi_table_parse_entries(char *id,
 352                         unsigned long table_size,
 353                         int entry_id,
 354                         acpi_tbl_entry_handler handler,
 355                         unsigned int max_entries)
 356 {
 357         struct acpi_subtable_proc proc = {
 358                 .id             = entry_id,
 359                 .handler        = handler,
 360         };
 361
 362         return acpi_table_parse_entries_array(id, table_size, &proc, 1,
 363                                                 max_entries);
 364 }
 365
 366 int __init
 367 acpi_table_parse_madt(enum acpi_madt_type id,
 368                       acpi_tbl_entry_handler handler, unsigned int max_entries)
 369 {
 370         return acpi_table_parse_entries(ACPI_SIG_MADT,
 371                                             sizeof(struct acpi_table_madt), id,
 372                                             handler, max_entries);
 373 }
 374
 375 /**
 376  * acpi_table_parse - find table with @id, run @handler on it
 377  * @id: table id to find
 378  * @handler: handler to run
 379  *
 380  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
 381  * run @handler on it.
 382  *
 383  * Return 0 if table found, -errno if not.
 384  */
 385 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
 386 {
 387         struct acpi_table_header *table = NULL;
 388
 389         if (acpi_disabled)
 390                 return -ENODEV;
 391
 392         if (!id || !handler)
 393                 return -EINVAL;
 394
 395         if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
 396                 acpi_get_table(id, acpi_apic_instance, &table);
 397         else
 398                 acpi_get_table(id, 0, &table);
 399
 400         if (table) {
 401                 handler(table);
 402                 acpi_put_table(table);
 403                 return 0;
 404         } else
 405                 return -ENODEV;
 406 }
 407
 408 /*
 409  * The BIOS is supposed to supply a single APIC/MADT,
 410  * but some report two.  Provide a knob to use either.
 411  * (don't you wish instance 0 and 1 were not the same?)
 412  */
 413 static void __init check_multiple_madt(void)
 414 {
 415         struct acpi_table_header *table = NULL;
 416
 417         acpi_get_table(ACPI_SIG_MADT, 2, &table);
 418         if (table) {
 419                 pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
 420                         acpi_apic_instance);
 421                 pr_warn("If \"acpi_apic_instance=%d\" works better, "
 422                         "notify linux-acpi@vger.kernel.org\n",
 423                         acpi_apic_instance ? 0 : 2);
 424                 acpi_put_table(table);
 425
 426         } else
 427                 acpi_apic_instance = 0;
 428
 429         return;
 430 }
 431
 432 static void acpi_table_taint(struct acpi_table_header *table)
 433 {
 434         pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
 435                 table->signature, table->oem_table_id);
 436         add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
 437 }
 438
 439 #ifdef CONFIG_ACPI_TABLE_UPGRADE
 440 static u64 acpi_tables_addr;
 441 static int all_tables_size;
 442
 443 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
 444 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
 445 {
 446         u8 sum = 0;
 447         u8 *end = buffer + length;
 448
 449         while (buffer < end)
 450                 sum = (u8) (sum + *(buffer++));
 451         return sum;
 452 }
 453
 454 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
 455 static const char * const table_sigs[] = {
 456         ACPI_SIG_BERT, ACPI_SIG_CPEP, ACPI_SIG_ECDT, ACPI_SIG_EINJ,
 457         ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT, ACPI_SIG_MSCT,
 458         ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT, ACPI_SIG_ASF,
 459         ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR, ACPI_SIG_HPET,
 460         ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG, ACPI_SIG_MCHI,
 461         ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI, ACPI_SIG_TCPA,
 462         ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT, ACPI_SIG_WDDT,
 463         ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT, ACPI_SIG_PSDT,
 464         ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT, ACPI_SIG_IORT,
 465         ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT, NULL };
 466
 467 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
 468
 469 #define NR_ACPI_INITRD_TABLES 64
 470 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
 471 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
 472
 473 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
 474
 475 void __init acpi_table_upgrade(void)
 476 {
 477         void *data = (void *)initrd_start;
 478         size_t size = initrd_end - initrd_start;
 479         int sig, no, table_nr = 0, total_offset = 0;
 480         long offset = 0;
 481         struct acpi_table_header *table;
 482         char cpio_path[32] = "kernel/firmware/acpi/";
 483         struct cpio_data file;
 484
 485         if (data == NULL || size == 0)
 486                 return;
 487
 488         for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
 489                 file = find_cpio_data(cpio_path, data, size, &offset);
 490                 if (!file.data)
 491                         break;
 492
 493                 data += offset;
 494                 size -= offset;
 495
 496                 if (file.size < sizeof(struct acpi_table_header)) {
 497                         pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
 498                                 cpio_path, file.name);
 499                         continue;
 500                 }
 501
 502                 table = file.data;
 503
 504                 for (sig = 0; table_sigs[sig]; sig++)
 505                         if (!memcmp(table->signature, table_sigs[sig], 4))
 506                                 break;
 507
 508                 if (!table_sigs[sig]) {
 509                         pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
 510                                 cpio_path, file.name);
 511                         continue;
 512                 }
 513                 if (file.size != table->length) {
 514                         pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
 515                                 cpio_path, file.name);
 516                         continue;
 517                 }
 518                 if (acpi_table_checksum(file.data, table->length)) {
 519                         pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
 520                                 cpio_path, file.name);
 521                         continue;
 522                 }
 523
 524                 pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
 525                         table->signature, cpio_path, file.name, table->length);
 526
 527                 all_tables_size += table->length;
 528                 acpi_initrd_files[table_nr].data = file.data;
 529                 acpi_initrd_files[table_nr].size = file.size;
 530                 table_nr++;
 531         }
 532         if (table_nr == 0)
 533                 return;
 534
 535         acpi_tables_addr =
 536                 memblock_find_in_range(0, ACPI_TABLE_UPGRADE_MAX_PHYS,
 537                                        all_tables_size, PAGE_SIZE);
 538         if (!acpi_tables_addr) {
 539                 WARN_ON(1);
 540                 return;
 541         }
 542         /*
 543          * Only calling e820_add_reserve does not work and the
 544          * tables are invalid (memory got used) later.
 545          * memblock_reserve works as expected and the tables won't get modified.
 546          * But it's not enough on X86 because ioremap will
 547          * complain later (used by acpi_os_map_memory) that the pages
 548          * that should get mapped are not marked "reserved".
 549          * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
 550          * works fine.
 551          */
 552         memblock_reserve(acpi_tables_addr, all_tables_size);
 553         arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
 554
 555         /*
 556          * early_ioremap only can remap 256k one time. If we map all
 557          * tables one time, we will hit the limit. Need to map chunks
 558          * one by one during copying the same as that in relocate_initrd().
 559          */
 560         for (no = 0; no < table_nr; no++) {
 561                 unsigned char *src_p = acpi_initrd_files[no].data;
 562                 phys_addr_t size = acpi_initrd_files[no].size;
 563                 phys_addr_t dest_addr = acpi_tables_addr + total_offset;
 564                 phys_addr_t slop, clen;
 565                 char *dest_p;
 566
 567                 total_offset += size;
 568
 569                 while (size) {
 570                         slop = dest_addr & ~PAGE_MASK;
 571                         clen = size;
 572                         if (clen > MAP_CHUNK_SIZE - slop)
 573                                 clen = MAP_CHUNK_SIZE - slop;
 574                         dest_p = early_memremap(dest_addr & PAGE_MASK,
 575                                                 clen + slop);
 576                         memcpy(dest_p + slop, src_p, clen);
 577                         early_memunmap(dest_p, clen + slop);
 578                         src_p += clen;
 579                         dest_addr += clen;
 580                         size -= clen;
 581                 }
 582         }
 583 }
 584
 585 static acpi_status
 586 acpi_table_initrd_override(struct acpi_table_header *existing_table,
 587                            acpi_physical_address *address, u32 *length)
 588 {
 589         int table_offset = 0;
 590         int table_index = 0;
 591         struct acpi_table_header *table;
 592         u32 table_length;
 593
 594         *length = 0;
 595         *address = 0;
 596         if (!acpi_tables_addr)
 597                 return AE_OK;
 598
 599         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
 600                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
 601                                            ACPI_HEADER_SIZE);
 602                 if (table_offset + table->length > all_tables_size) {
 603                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 604                         WARN_ON(1);
 605                         return AE_OK;
 606                 }
 607
 608                 table_length = table->length;
 609
 610                 /* Only override tables matched */
 611                 if (memcmp(existing_table->signature, table->signature, 4) ||
 612                     memcmp(table->oem_id, existing_table->oem_id,
 613                            ACPI_OEM_ID_SIZE) ||
 614                     memcmp(table->oem_table_id, existing_table->oem_table_id,
 615                            ACPI_OEM_TABLE_ID_SIZE)) {
 616                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 617                         goto next_table;
 618                 }
 619                 /*
 620                  * Mark the table to avoid being used in
 621                  * acpi_table_initrd_scan() and check the revision.
 622                  */
 623                 if (test_and_set_bit(table_index, acpi_initrd_installed) ||
 624                     existing_table->oem_revision >= table->oem_revision) {
 625                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 626                         goto next_table;
 627                 }
 628
 629                 *length = table_length;
 630                 *address = acpi_tables_addr + table_offset;
 631                 pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
 632                         table->signature, table->oem_id,
 633                         table->oem_table_id);
 634                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 635                 break;
 636
 637 next_table:
 638                 table_offset += table_length;
 639                 table_index++;
 640         }
 641         return AE_OK;
 642 }
 643
 644 static void __init acpi_table_initrd_scan(void)
 645 {
 646         int table_offset = 0;
 647         int table_index = 0;
 648         u32 table_length;
 649         struct acpi_table_header *table;
 650
 651         if (!acpi_tables_addr)
 652                 return;
 653
 654         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
 655                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
 656                                            ACPI_HEADER_SIZE);
 657                 if (table_offset + table->length > all_tables_size) {
 658                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 659                         WARN_ON(1);
 660                         return;
 661                 }
 662
 663                 table_length = table->length;
 664
 665                 /* Skip RSDT/XSDT which should only be used for override */
 666                 if (ACPI_COMPARE_NAME(table->signature, ACPI_SIG_RSDT) ||
 667                     ACPI_COMPARE_NAME(table->signature, ACPI_SIG_XSDT)) {
 668                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 669                         goto next_table;
 670                 }
 671                 /*
 672                  * Mark the table to avoid being used in
 673                  * acpi_table_initrd_override(). Though this is not possible
 674                  * because override is disabled in acpi_install_table().
 675                  */
 676                 if (test_and_set_bit(table_index, acpi_initrd_installed)) {
 677                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 678                         goto next_table;
 679                 }
 680
 681                 pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
 682                         table->signature, table->oem_id,
 683                         table->oem_table_id);
 684                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 685                 acpi_install_table(acpi_tables_addr + table_offset, TRUE);
 686 next_table:
 687                 table_offset += table_length;
 688                 table_index++;
 689         }
 690 }
 691 #else
 692 static acpi_status
 693 acpi_table_initrd_override(struct acpi_table_header *existing_table,
 694                            acpi_physical_address *address,
 695                            u32 *table_length)
 696 {
 697         *table_length = 0;
 698         *address = 0;
 699         return AE_OK;
 700 }
 701
 702 static void __init acpi_table_initrd_scan(void)
 703 {
 704 }
 705 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
 706
 707 acpi_status
 708 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
 709                                 acpi_physical_address *address,
 710                                 u32 *table_length)
 711 {
 712         return acpi_table_initrd_override(existing_table, address,
 713                                           table_length);
 714 }
 715
 716 acpi_status
 717 acpi_os_table_override(struct acpi_table_header *existing_table,
 718                        struct acpi_table_header **new_table)
 719 {
 720         if (!existing_table || !new_table)
 721                 return AE_BAD_PARAMETER;
 722
 723         *new_table = NULL;
 724
 725 #ifdef CONFIG_ACPI_CUSTOM_DSDT
 726         if (strncmp(existing_table->signature, "DSDT", 4) == 0)
 727                 *new_table = (struct acpi_table_header *)AmlCode;
 728 #endif
 729         if (*new_table != NULL)
 730                 acpi_table_taint(existing_table);
 731         return AE_OK;
 732 }
 733
 734 /*
 735  * acpi_table_init()
 736  *
 737  * find RSDP, find and checksum SDT/XSDT.
 738  * checksum all tables, print SDT/XSDT
 739  *
 740  * result: sdt_entry[] is initialized
 741  */
 742
 743 int __init acpi_table_init(void)
 744 {
 745         acpi_status status;
 746
 747         if (acpi_verify_table_checksum) {
 748                 pr_info("Early table checksum verification enabled\n");
 749                 acpi_gbl_enable_table_validation = TRUE;
 750         } else {
 751                 pr_info("Early table checksum verification disabled\n");
 752                 acpi_gbl_enable_table_validation = FALSE;
 753         }
 754
 755         status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
 756         if (ACPI_FAILURE(status))
 757                 return -EINVAL;
 758         acpi_table_initrd_scan();
 759
 760         check_multiple_madt();
 761         return 0;
 762 }
 763
 764 static int __init acpi_parse_apic_instance(char *str)
 765 {
 766         if (!str)
 767                 return -EINVAL;
 768
 769         if (kstrtoint(str, 0, &acpi_apic_instance))
 770                 return -EINVAL;
 771
 772         pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
 773
 774         return 0;
 775 }
 776
 777 early_param("acpi_apic_instance", acpi_parse_apic_instance);
 778
 779 static int __init acpi_force_table_verification_setup(char *s)
 780 {
 781         acpi_verify_table_checksum = true;
 782
 783         return 0;
 784 }
 785
 786 early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
 787
 788 static int __init acpi_force_32bit_fadt_addr(char *s)
 789 {
 790         pr_info("Forcing 32 Bit FADT addresses\n");
 791         acpi_gbl_use32_bit_fadt_addresses = TRUE;
 792
 793         return 0;
 794 }
 795
 796 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);