drivers/acpi/tables.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  acpi_tables.c - ACPI Boot-Time Table Parsing
   4  *
   5  *  Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  */
   7
   8 /* Uncomment next line to get verbose printout */
   9 /* #define DEBUG */
  10 #define pr_fmt(fmt) "ACPI: " fmt
  11
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/smp.h>
  15 #include <linux/string.h>
  16 #include <linux/types.h>
  17 #include <linux/irq.h>
  18 #include <linux/errno.h>
  19 #include <linux/acpi.h>
  20 #include <linux/memblock.h>
  21 #include <linux/earlycpio.h>
  22 #include <linux/initrd.h>
  23 #include <linux/security.h>
  24 #include <linux/kmemleak.h>
  25 #include "internal.h"
  26
  27 #ifdef CONFIG_ACPI_CUSTOM_DSDT
  28 #include CONFIG_ACPI_CUSTOM_DSDT_FILE
  29 #endif
  30
  31 #define ACPI_MAX_TABLES         128
  32
  33 static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
  34 static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
  35
  36 static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
  37
  38 static int acpi_apic_instance __initdata_or_acpilib;
  39
  40 /*
  41  * Disable table checksum verification for the early stage due to the size
  42  * limitation of the current x86 early mapping implementation.
  43  */
  44 static bool acpi_verify_table_checksum __initdata_or_acpilib = false;
  45
  46 void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
  47 {
  48         if (!header)
  49                 return;
  50
  51         switch (header->type) {
  52
  53         case ACPI_MADT_TYPE_LOCAL_APIC:
  54                 {
  55                         struct acpi_madt_local_apic *p =
  56                             (struct acpi_madt_local_apic *)header;
  57                         pr_debug("LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
  58                                  p->processor_id, p->id,
  59                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
  60                 }
  61                 break;
  62
  63         case ACPI_MADT_TYPE_LOCAL_X2APIC:
  64                 {
  65                         struct acpi_madt_local_x2apic *p =
  66                             (struct acpi_madt_local_x2apic *)header;
  67                         pr_debug("X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
  68                                  p->local_apic_id, p->uid,
  69                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
  70                 }
  71                 break;
  72
  73         case ACPI_MADT_TYPE_IO_APIC:
  74                 {
  75                         struct acpi_madt_io_apic *p =
  76                             (struct acpi_madt_io_apic *)header;
  77                         pr_debug("IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
  78                                  p->id, p->address, p->global_irq_base);
  79                 }
  80                 break;
  81
  82         case ACPI_MADT_TYPE_INTERRUPT_OVERRIDE:
  83                 {
  84                         struct acpi_madt_interrupt_override *p =
  85                             (struct acpi_madt_interrupt_override *)header;
  86                         pr_info("INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
  87                                 p->bus, p->source_irq, p->global_irq,
  88                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
  89                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2]);
  90                         if (p->inti_flags  &
  91                             ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK))
  92                                 pr_info("INT_SRC_OVR unexpected reserved flags: 0x%x\n",
  93                                         p->inti_flags  &
  94                                         ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK));
  95                 }
  96                 break;
  97
  98         case ACPI_MADT_TYPE_NMI_SOURCE:
  99                 {
 100                         struct acpi_madt_nmi_source *p =
 101                             (struct acpi_madt_nmi_source *)header;
 102                         pr_info("NMI_SRC (%s %s global_irq %d)\n",
 103                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
 104                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
 105                                 p->global_irq);
 106                 }
 107                 break;
 108
 109         case ACPI_MADT_TYPE_LOCAL_APIC_NMI:
 110                 {
 111                         struct acpi_madt_local_apic_nmi *p =
 112                             (struct acpi_madt_local_apic_nmi *)header;
 113                         pr_info("LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
 114                                 p->processor_id,
 115                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK ],
 116                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
 117                                 p->lint);
 118                 }
 119                 break;
 120
 121         case ACPI_MADT_TYPE_LOCAL_X2APIC_NMI:
 122                 {
 123                         u16 polarity, trigger;
 124                         struct acpi_madt_local_x2apic_nmi *p =
 125                             (struct acpi_madt_local_x2apic_nmi *)header;
 126
 127                         polarity = p->inti_flags & ACPI_MADT_POLARITY_MASK;
 128                         trigger = (p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
 129
 130                         pr_info("X2APIC_NMI (uid[0x%02x] %s %s lint[0x%x])\n",
 131                                 p->uid,
 132                                 mps_inti_flags_polarity[polarity],
 133                                 mps_inti_flags_trigger[trigger],
 134                                 p->lint);
 135                 }
 136                 break;
 137
 138         case ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE:
 139                 {
 140                         struct acpi_madt_local_apic_override *p =
 141                             (struct acpi_madt_local_apic_override *)header;
 142                         pr_info("LAPIC_ADDR_OVR (address[0x%llx])\n",
 143                                 p->address);
 144                 }
 145                 break;
 146
 147         case ACPI_MADT_TYPE_IO_SAPIC:
 148                 {
 149                         struct acpi_madt_io_sapic *p =
 150                             (struct acpi_madt_io_sapic *)header;
 151                         pr_debug("IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
 152                                  p->id, (void *)(unsigned long)p->address,
 153                                  p->global_irq_base);
 154                 }
 155                 break;
 156
 157         case ACPI_MADT_TYPE_LOCAL_SAPIC:
 158                 {
 159                         struct acpi_madt_local_sapic *p =
 160                             (struct acpi_madt_local_sapic *)header;
 161                         pr_debug("LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
 162                                  p->processor_id, p->id, p->eid,
 163                                  (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
 164                 }
 165                 break;
 166
 167         case ACPI_MADT_TYPE_INTERRUPT_SOURCE:
 168                 {
 169                         struct acpi_madt_interrupt_source *p =
 170                             (struct acpi_madt_interrupt_source *)header;
 171                         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",
 172                                 mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
 173                                 mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
 174                                 p->type, p->id, p->eid, p->io_sapic_vector,
 175                                 p->global_irq);
 176                 }
 177                 break;
 178
 179         case ACPI_MADT_TYPE_GENERIC_INTERRUPT:
 180                 {
 181                         struct acpi_madt_generic_interrupt *p =
 182                                 (struct acpi_madt_generic_interrupt *)header;
 183                         pr_debug("GICC (acpi_id[0x%04x] address[%llx] MPIDR[0x%llx] %s)\n",
 184                                  p->uid, p->base_address,
 185                                  p->arm_mpidr,
 186                                  (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
 187
 188                 }
 189                 break;
 190
 191         case ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR:
 192                 {
 193                         struct acpi_madt_generic_distributor *p =
 194                                 (struct acpi_madt_generic_distributor *)header;
 195                         pr_debug("GIC Distributor (gic_id[0x%04x] address[%llx] gsi_base[%d])\n",
 196                                  p->gic_id, p->base_address,
 197                                  p->global_irq_base);
 198                 }
 199                 break;
 200
 201         case ACPI_MADT_TYPE_CORE_PIC:
 202                 {
 203                         struct acpi_madt_core_pic *p = (struct acpi_madt_core_pic *)header;
 204
 205                         pr_debug("CORE PIC (processor_id[0x%02x] core_id[0x%02x] %s)\n",
 206                                  p->processor_id, p->core_id,
 207                                  (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
 208                 }
 209                 break;
 210
 211         case ACPI_MADT_TYPE_RINTC:
 212                 {
 213                         struct acpi_madt_rintc *p = (struct acpi_madt_rintc *)header;
 214
 215                         pr_debug("RISC-V INTC (acpi_uid[0x%04x] hart_id[0x%llx] %s)\n",
 216                                  p->uid, p->hart_id,
 217                                  (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
 218                 }
 219                 break;
 220
 221         default:
 222                 pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
 223                         header->type);
 224                 break;
 225         }
 226 }
 227
 228 int __init_or_acpilib acpi_table_parse_entries_array(
 229         char *id, unsigned long table_size, struct acpi_subtable_proc *proc,
 230         int proc_num, unsigned int max_entries)
 231 {
 232         struct acpi_table_header *table_header = NULL;
 233         int count;
 234         u32 instance = 0;
 235
 236         if (acpi_disabled)
 237                 return -ENODEV;
 238
 239         if (!id)
 240                 return -EINVAL;
 241
 242         if (!table_size)
 243                 return -EINVAL;
 244
 245         if (!strncmp(id, ACPI_SIG_MADT, 4))
 246                 instance = acpi_apic_instance;
 247
 248         acpi_get_table(id, instance, &table_header);
 249         if (!table_header) {
 250                 pr_debug("%4.4s not present\n", id);
 251                 return -ENODEV;
 252         }
 253
 254         count = acpi_parse_entries_array(id, table_size, table_header,
 255                         proc, proc_num, max_entries);
 256
 257         acpi_put_table(table_header);
 258         return count;
 259 }
 260
 261 static int __init_or_acpilib __acpi_table_parse_entries(
 262         char *id, unsigned long table_size, int entry_id,
 263         acpi_tbl_entry_handler handler, acpi_tbl_entry_handler_arg handler_arg,
 264         void *arg, unsigned int max_entries)
 265 {
 266         struct acpi_subtable_proc proc = {
 267                 .id             = entry_id,
 268                 .handler        = handler,
 269                 .handler_arg    = handler_arg,
 270                 .arg            = arg,
 271         };
 272
 273         return acpi_table_parse_entries_array(id, table_size, &proc, 1,
 274                                                 max_entries);
 275 }
 276
 277 int __init_or_acpilib
 278 acpi_table_parse_cedt(enum acpi_cedt_type id,
 279                       acpi_tbl_entry_handler_arg handler_arg, void *arg)
 280 {
 281         return __acpi_table_parse_entries(ACPI_SIG_CEDT,
 282                                           sizeof(struct acpi_table_cedt), id,
 283                                           NULL, handler_arg, arg, 0);
 284 }
 285 EXPORT_SYMBOL_ACPI_LIB(acpi_table_parse_cedt);
 286
 287 int __init acpi_table_parse_entries(char *id, unsigned long table_size,
 288                                     int entry_id,
 289                                     acpi_tbl_entry_handler handler,
 290                                     unsigned int max_entries)
 291 {
 292         return __acpi_table_parse_entries(id, table_size, entry_id, handler,
 293                                           NULL, NULL, max_entries);
 294 }
 295
 296 int __init acpi_table_parse_madt(enum acpi_madt_type id,
 297                       acpi_tbl_entry_handler handler, unsigned int max_entries)
 298 {
 299         return acpi_table_parse_entries(ACPI_SIG_MADT,
 300                                             sizeof(struct acpi_table_madt), id,
 301                                             handler, max_entries);
 302 }
 303
 304 /**
 305  * acpi_table_parse - find table with @id, run @handler on it
 306  * @id: table id to find
 307  * @handler: handler to run
 308  *
 309  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
 310  * run @handler on it.
 311  *
 312  * Return 0 if table found, -errno if not.
 313  */
 314 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
 315 {
 316         struct acpi_table_header *table = NULL;
 317
 318         if (acpi_disabled)
 319                 return -ENODEV;
 320
 321         if (!id || !handler)
 322                 return -EINVAL;
 323
 324         if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
 325                 acpi_get_table(id, acpi_apic_instance, &table);
 326         else
 327                 acpi_get_table(id, 0, &table);
 328
 329         if (table) {
 330                 handler(table);
 331                 acpi_put_table(table);
 332                 return 0;
 333         } else
 334                 return -ENODEV;
 335 }
 336
 337 /*
 338  * The BIOS is supposed to supply a single APIC/MADT,
 339  * but some report two.  Provide a knob to use either.
 340  * (don't you wish instance 0 and 1 were not the same?)
 341  */
 342 static void __init check_multiple_madt(void)
 343 {
 344         struct acpi_table_header *table = NULL;
 345
 346         acpi_get_table(ACPI_SIG_MADT, 2, &table);
 347         if (table) {
 348                 pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
 349                         acpi_apic_instance);
 350                 pr_warn("If \"acpi_apic_instance=%d\" works better, "
 351                         "notify linux-acpi@vger.kernel.org\n",
 352                         acpi_apic_instance ? 0 : 2);
 353                 acpi_put_table(table);
 354
 355         } else
 356                 acpi_apic_instance = 0;
 357
 358         return;
 359 }
 360
 361 static void acpi_table_taint(struct acpi_table_header *table)
 362 {
 363         pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
 364                 table->signature, table->oem_table_id);
 365         add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
 366 }
 367
 368 #ifdef CONFIG_ACPI_TABLE_UPGRADE
 369 static u64 acpi_tables_addr;
 370 static int all_tables_size;
 371
 372 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
 373 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
 374 {
 375         u8 sum = 0;
 376         u8 *end = buffer + length;
 377
 378         while (buffer < end)
 379                 sum = (u8) (sum + *(buffer++));
 380         return sum;
 381 }
 382
 383 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
 384 static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst = {
 385         ACPI_SIG_BERT, ACPI_SIG_BGRT, ACPI_SIG_CPEP, ACPI_SIG_ECDT,
 386         ACPI_SIG_EINJ, ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT,
 387         ACPI_SIG_MSCT, ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT,
 388         ACPI_SIG_ASF,  ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR,
 389         ACPI_SIG_HPET, ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG,
 390         ACPI_SIG_MCHI, ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI,
 391         ACPI_SIG_TCPA, ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT,
 392         ACPI_SIG_WDDT, ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT,
 393         ACPI_SIG_PSDT, ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT,
 394         ACPI_SIG_IORT, ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT,
 395         ACPI_SIG_NHLT, ACPI_SIG_AEST, ACPI_SIG_CEDT, ACPI_SIG_AGDI,
 396         ACPI_SIG_NBFT };
 397
 398 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
 399
 400 #define NR_ACPI_INITRD_TABLES 64
 401 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
 402 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
 403
 404 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
 405
 406 void __init acpi_table_upgrade(void)
 407 {
 408         void *data;
 409         size_t size;
 410         int sig, no, table_nr = 0, total_offset = 0;
 411         long offset = 0;
 412         struct acpi_table_header *table;
 413         char cpio_path[32] = "kernel/firmware/acpi/";
 414         struct cpio_data file;
 415
 416         if (IS_ENABLED(CONFIG_ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD)) {
 417                 data = __initramfs_start;
 418                 size = __initramfs_size;
 419         } else {
 420                 data = (void *)initrd_start;
 421                 size = initrd_end - initrd_start;
 422         }
 423
 424         if (data == NULL || size == 0)
 425                 return;
 426
 427         for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
 428                 file = find_cpio_data(cpio_path, data, size, &offset);
 429                 if (!file.data)
 430                         break;
 431
 432                 data += offset;
 433                 size -= offset;
 434
 435                 if (file.size < sizeof(struct acpi_table_header)) {
 436                         pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
 437                                 cpio_path, file.name);
 438                         continue;
 439                 }
 440
 441                 table = file.data;
 442
 443                 for (sig = 0; sig < ARRAY_SIZE(table_sigs); sig++)
 444                         if (!memcmp(table->signature, table_sigs[sig], 4))
 445                                 break;
 446
 447                 if (sig >= ARRAY_SIZE(table_sigs)) {
 448                         pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
 449                                 cpio_path, file.name);
 450                         continue;
 451                 }
 452                 if (file.size != table->length) {
 453                         pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
 454                                 cpio_path, file.name);
 455                         continue;
 456                 }
 457                 if (acpi_table_checksum(file.data, table->length)) {
 458                         pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
 459                                 cpio_path, file.name);
 460                         continue;
 461                 }
 462
 463                 pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
 464                         table->signature, cpio_path, file.name, table->length);
 465
 466                 all_tables_size += table->length;
 467                 acpi_initrd_files[table_nr].data = file.data;
 468                 acpi_initrd_files[table_nr].size = file.size;
 469                 table_nr++;
 470         }
 471         if (table_nr == 0)
 472                 return;
 473
 474         if (security_locked_down(LOCKDOWN_ACPI_TABLES)) {
 475                 pr_notice("kernel is locked down, ignoring table override\n");
 476                 return;
 477         }
 478
 479         acpi_tables_addr =
 480                 memblock_phys_alloc_range(all_tables_size, PAGE_SIZE,
 481                                           0, ACPI_TABLE_UPGRADE_MAX_PHYS);
 482         if (!acpi_tables_addr) {
 483                 WARN_ON(1);
 484                 return;
 485         }
 486         /*
 487          * Only calling e820_add_reserve does not work and the
 488          * tables are invalid (memory got used) later.
 489          * memblock_reserve works as expected and the tables won't get modified.
 490          * But it's not enough on X86 because ioremap will
 491          * complain later (used by acpi_os_map_memory) that the pages
 492          * that should get mapped are not marked "reserved".
 493          * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
 494          * works fine.
 495          */
 496         arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
 497
 498         kmemleak_ignore_phys(acpi_tables_addr);
 499
 500         /*
 501          * early_ioremap only can remap 256k one time. If we map all
 502          * tables one time, we will hit the limit. Need to map chunks
 503          * one by one during copying the same as that in relocate_initrd().
 504          */
 505         for (no = 0; no < table_nr; no++) {
 506                 unsigned char *src_p = acpi_initrd_files[no].data;
 507                 phys_addr_t size = acpi_initrd_files[no].size;
 508                 phys_addr_t dest_addr = acpi_tables_addr + total_offset;
 509                 phys_addr_t slop, clen;
 510                 char *dest_p;
 511
 512                 total_offset += size;
 513
 514                 while (size) {
 515                         slop = dest_addr & ~PAGE_MASK;
 516                         clen = size;
 517                         if (clen > MAP_CHUNK_SIZE - slop)
 518                                 clen = MAP_CHUNK_SIZE - slop;
 519                         dest_p = early_memremap(dest_addr & PAGE_MASK,
 520                                                 clen + slop);
 521                         memcpy(dest_p + slop, src_p, clen);
 522                         early_memunmap(dest_p, clen + slop);
 523                         src_p += clen;
 524                         dest_addr += clen;
 525                         size -= clen;
 526                 }
 527         }
 528 }
 529
 530 static acpi_status
 531 acpi_table_initrd_override(struct acpi_table_header *existing_table,
 532                            acpi_physical_address *address, u32 *length)
 533 {
 534         int table_offset = 0;
 535         int table_index = 0;
 536         struct acpi_table_header *table;
 537         u32 table_length;
 538
 539         *length = 0;
 540         *address = 0;
 541         if (!acpi_tables_addr)
 542                 return AE_OK;
 543
 544         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
 545                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
 546                                            ACPI_HEADER_SIZE);
 547                 if (table_offset + table->length > all_tables_size) {
 548                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 549                         WARN_ON(1);
 550                         return AE_OK;
 551                 }
 552
 553                 table_length = table->length;
 554
 555                 /* Only override tables matched */
 556                 if (memcmp(existing_table->signature, table->signature, 4) ||
 557                     memcmp(table->oem_id, existing_table->oem_id,
 558                            ACPI_OEM_ID_SIZE) ||
 559                     memcmp(table->oem_table_id, existing_table->oem_table_id,
 560                            ACPI_OEM_TABLE_ID_SIZE)) {
 561                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 562                         goto next_table;
 563                 }
 564                 /*
 565                  * Mark the table to avoid being used in
 566                  * acpi_table_initrd_scan() and check the revision.
 567                  */
 568                 if (test_and_set_bit(table_index, acpi_initrd_installed) ||
 569                     existing_table->oem_revision >= table->oem_revision) {
 570                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 571                         goto next_table;
 572                 }
 573
 574                 *length = table_length;
 575                 *address = acpi_tables_addr + table_offset;
 576                 pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
 577                         table->signature, table->oem_id,
 578                         table->oem_table_id);
 579                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 580                 break;
 581
 582 next_table:
 583                 table_offset += table_length;
 584                 table_index++;
 585         }
 586         return AE_OK;
 587 }
 588
 589 static void __init acpi_table_initrd_scan(void)
 590 {
 591         int table_offset = 0;
 592         int table_index = 0;
 593         u32 table_length;
 594         struct acpi_table_header *table;
 595
 596         if (!acpi_tables_addr)
 597                 return;
 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;
 606                 }
 607
 608                 table_length = table->length;
 609
 610                 /* Skip RSDT/XSDT which should only be used for override */
 611                 if (ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_RSDT) ||
 612                     ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_XSDT)) {
 613                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 614                         goto next_table;
 615                 }
 616                 /*
 617                  * Mark the table to avoid being used in
 618                  * acpi_table_initrd_override(). Though this is not possible
 619                  * because override is disabled in acpi_install_physical_table().
 620                  */
 621                 if (test_and_set_bit(table_index, acpi_initrd_installed)) {
 622                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 623                         goto next_table;
 624                 }
 625
 626                 pr_info("Table Upgrade: install [%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                 acpi_install_physical_table(acpi_tables_addr + table_offset);
 631 next_table:
 632                 table_offset += table_length;
 633                 table_index++;
 634         }
 635 }
 636 #else
 637 static acpi_status
 638 acpi_table_initrd_override(struct acpi_table_header *existing_table,
 639                            acpi_physical_address *address,
 640                            u32 *table_length)
 641 {
 642         *table_length = 0;
 643         *address = 0;
 644         return AE_OK;
 645 }
 646
 647 static void __init acpi_table_initrd_scan(void)
 648 {
 649 }
 650 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
 651
 652 acpi_status
 653 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
 654                                 acpi_physical_address *address,
 655                                 u32 *table_length)
 656 {
 657         return acpi_table_initrd_override(existing_table, address,
 658                                           table_length);
 659 }
 660
 661 #ifdef CONFIG_ACPI_CUSTOM_DSDT
 662 static void *amlcode __attribute__ ((weakref("AmlCode")));
 663 static void *dsdt_amlcode __attribute__ ((weakref("dsdt_aml_code")));
 664 #endif
 665
 666 acpi_status acpi_os_table_override(struct acpi_table_header *existing_table,
 667                        struct acpi_table_header **new_table)
 668 {
 669         if (!existing_table || !new_table)
 670                 return AE_BAD_PARAMETER;
 671
 672         *new_table = NULL;
 673
 674 #ifdef CONFIG_ACPI_CUSTOM_DSDT
 675         if (!strncmp(existing_table->signature, "DSDT", 4)) {
 676                 *new_table = (struct acpi_table_header *)&amlcode;
 677                 if (!(*new_table))
 678                         *new_table = (struct acpi_table_header *)&dsdt_amlcode;
 679         }
 680 #endif
 681         if (*new_table != NULL)
 682                 acpi_table_taint(existing_table);
 683         return AE_OK;
 684 }
 685
 686 /*
 687  * acpi_locate_initial_tables()
 688  *
 689  * Get the RSDP, then find and checksum all the ACPI tables.
 690  *
 691  * result: initial_tables[] is initialized, and points to
 692  * a list of ACPI tables.
 693  */
 694 int __init acpi_locate_initial_tables(void)
 695 {
 696         acpi_status status;
 697
 698         if (acpi_verify_table_checksum) {
 699                 pr_info("Early table checksum verification enabled\n");
 700                 acpi_gbl_enable_table_validation = TRUE;
 701         } else {
 702                 pr_info("Early table checksum verification disabled\n");
 703                 acpi_gbl_enable_table_validation = FALSE;
 704         }
 705
 706         status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
 707         if (ACPI_FAILURE(status))
 708                 return -EINVAL;
 709
 710         return 0;
 711 }
 712
 713 void __init acpi_reserve_initial_tables(void)
 714 {
 715         int i;
 716
 717         for (i = 0; i < ACPI_MAX_TABLES; i++) {
 718                 struct acpi_table_desc *table_desc = &initial_tables[i];
 719                 u64 start = table_desc->address;
 720                 u64 size = table_desc->length;
 721
 722                 if (!start || !size)
 723                         break;
 724
 725                 pr_info("Reserving %4s table memory at [mem 0x%llx-0x%llx]\n",
 726                         table_desc->signature.ascii, start, start + size - 1);
 727
 728                 memblock_reserve(start, size);
 729         }
 730 }
 731
 732 void __init acpi_table_init_complete(void)
 733 {
 734         acpi_table_initrd_scan();
 735         check_multiple_madt();
 736 }
 737
 738 int __init acpi_table_init(void)
 739 {
 740         int ret;
 741
 742         ret = acpi_locate_initial_tables();
 743         if (ret)
 744                 return ret;
 745
 746         acpi_table_init_complete();
 747
 748         return 0;
 749 }
 750
 751 static int __init acpi_parse_apic_instance(char *str)
 752 {
 753         if (!str)
 754                 return -EINVAL;
 755
 756         if (kstrtoint(str, 0, &acpi_apic_instance))
 757                 return -EINVAL;
 758
 759         pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
 760
 761         return 0;
 762 }
 763 early_param("acpi_apic_instance", acpi_parse_apic_instance);
 764
 765 static int __init acpi_force_table_verification_setup(char *s)
 766 {
 767         acpi_verify_table_checksum = true;
 768
 769         return 0;
 770 }
 771 early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
 772
 773 static int __init acpi_force_32bit_fadt_addr(char *s)
 774 {
 775         pr_info("Forcing 32 Bit FADT addresses\n");
 776         acpi_gbl_use32_bit_fadt_addresses = TRUE;
 777
 778         return 0;
 779 }
 780 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);