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 <[email protected]>
   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_MULTIPROC_WAKEUP:
 202                 {
 203                         struct acpi_madt_multiproc_wakeup *p =
 204                                 (struct acpi_madt_multiproc_wakeup *)header;
 205                         u64 reset_vector = 0;
 206
 207                         if (p->version >= ACPI_MADT_MP_WAKEUP_VERSION_V1)
 208                                 reset_vector = p->reset_vector;
 209
 210                         pr_debug("MP Wakeup (version[%d], mailbox[%#llx], reset[%#llx])\n",
 211                                  p->version, p->mailbox_address, reset_vector);
 212                 }
 213                 break;
 214
 215         case ACPI_MADT_TYPE_CORE_PIC:
 216                 {
 217                         struct acpi_madt_core_pic *p = (struct acpi_madt_core_pic *)header;
 218
 219                         pr_debug("CORE PIC (processor_id[0x%02x] core_id[0x%02x] %s)\n",
 220                                  p->processor_id, p->core_id,
 221                                  (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
 222                 }
 223                 break;
 224
 225         case ACPI_MADT_TYPE_RINTC:
 226                 {
 227                         struct acpi_madt_rintc *p = (struct acpi_madt_rintc *)header;
 228
 229                         pr_debug("RISC-V INTC (acpi_uid[0x%04x] hart_id[0x%llx] %s)\n",
 230                                  p->uid, p->hart_id,
 231                                  (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
 232                 }
 233                 break;
 234
 235         default:
 236                 pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
 237                         header->type);
 238                 break;
 239         }
 240 }
 241
 242 int __init_or_acpilib acpi_table_parse_entries_array(
 243         char *id, unsigned long table_size, struct acpi_subtable_proc *proc,
 244         int proc_num, unsigned int max_entries)
 245 {
 246         struct acpi_table_header *table_header = NULL;
 247         int count;
 248         u32 instance = 0;
 249
 250         if (acpi_disabled)
 251                 return -ENODEV;
 252
 253         if (!id)
 254                 return -EINVAL;
 255
 256         if (!table_size)
 257                 return -EINVAL;
 258
 259         if (!strncmp(id, ACPI_SIG_MADT, 4))
 260                 instance = acpi_apic_instance;
 261
 262         acpi_get_table(id, instance, &table_header);
 263         if (!table_header) {
 264                 pr_debug("%4.4s not present\n", id);
 265                 return -ENODEV;
 266         }
 267
 268         count = acpi_parse_entries_array(id, table_size,
 269                                          (union fw_table_header *)table_header,
 270                                          0, proc, proc_num, max_entries);
 271
 272         acpi_put_table(table_header);
 273         return count;
 274 }
 275
 276 static int __init_or_acpilib __acpi_table_parse_entries(
 277         char *id, unsigned long table_size, int entry_id,
 278         acpi_tbl_entry_handler handler, acpi_tbl_entry_handler_arg handler_arg,
 279         void *arg, unsigned int max_entries)
 280 {
 281         struct acpi_subtable_proc proc = {
 282                 .id             = entry_id,
 283                 .handler        = handler,
 284                 .handler_arg    = handler_arg,
 285                 .arg            = arg,
 286         };
 287
 288         return acpi_table_parse_entries_array(id, table_size, &proc, 1,
 289                                                 max_entries);
 290 }
 291
 292 int __init_or_acpilib
 293 acpi_table_parse_cedt(enum acpi_cedt_type id,
 294                       acpi_tbl_entry_handler_arg handler_arg, void *arg)
 295 {
 296         return __acpi_table_parse_entries(ACPI_SIG_CEDT,
 297                                           sizeof(struct acpi_table_cedt), id,
 298                                           NULL, handler_arg, arg, 0);
 299 }
 300 EXPORT_SYMBOL_ACPI_LIB(acpi_table_parse_cedt);
 301
 302 int __init acpi_table_parse_entries(char *id, unsigned long table_size,
 303                                     int entry_id,
 304                                     acpi_tbl_entry_handler handler,
 305                                     unsigned int max_entries)
 306 {
 307         return __acpi_table_parse_entries(id, table_size, entry_id, handler,
 308                                           NULL, NULL, max_entries);
 309 }
 310
 311 int __init acpi_table_parse_madt(enum acpi_madt_type id,
 312                       acpi_tbl_entry_handler handler, unsigned int max_entries)
 313 {
 314         return acpi_table_parse_entries(ACPI_SIG_MADT,
 315                                             sizeof(struct acpi_table_madt), id,
 316                                             handler, max_entries);
 317 }
 318
 319 /**
 320  * acpi_table_parse - find table with @id, run @handler on it
 321  * @id: table id to find
 322  * @handler: handler to run
 323  *
 324  * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
 325  * run @handler on it.
 326  *
 327  * Return 0 if table found, -errno if not.
 328  */
 329 int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
 330 {
 331         struct acpi_table_header *table = NULL;
 332
 333         if (acpi_disabled)
 334                 return -ENODEV;
 335
 336         if (!id || !handler)
 337                 return -EINVAL;
 338
 339         if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
 340                 acpi_get_table(id, acpi_apic_instance, &table);
 341         else
 342                 acpi_get_table(id, 0, &table);
 343
 344         if (table) {
 345                 handler(table);
 346                 acpi_put_table(table);
 347                 return 0;
 348         } else
 349                 return -ENODEV;
 350 }
 351
 352 /*
 353  * The BIOS is supposed to supply a single APIC/MADT,
 354  * but some report two.  Provide a knob to use either.
 355  * (don't you wish instance 0 and 1 were not the same?)
 356  */
 357 static void __init check_multiple_madt(void)
 358 {
 359         struct acpi_table_header *table = NULL;
 360
 361         acpi_get_table(ACPI_SIG_MADT, 2, &table);
 362         if (table) {
 363                 pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
 364                         acpi_apic_instance);
 365                 pr_warn("If \"acpi_apic_instance=%d\" works better, "
 366                         "notify [email protected]\n",
 367                         acpi_apic_instance ? 0 : 2);
 368                 acpi_put_table(table);
 369
 370         } else
 371                 acpi_apic_instance = 0;
 372
 373         return;
 374 }
 375
 376 static void acpi_table_taint(struct acpi_table_header *table)
 377 {
 378         pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
 379                 table->signature, table->oem_table_id);
 380         add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
 381 }
 382
 383 #ifdef CONFIG_ACPI_TABLE_UPGRADE
 384 static u64 acpi_tables_addr;
 385 static int all_tables_size;
 386
 387 /* Copied from acpica/tbutils.c:acpi_tb_checksum() */
 388 static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
 389 {
 390         u8 sum = 0;
 391         u8 *end = buffer + length;
 392
 393         while (buffer < end)
 394                 sum = (u8) (sum + *(buffer++));
 395         return sum;
 396 }
 397
 398 /* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
 399 static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst = {
 400         ACPI_SIG_BERT, ACPI_SIG_BGRT, ACPI_SIG_CPEP, ACPI_SIG_ECDT,
 401         ACPI_SIG_EINJ, ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT,
 402         ACPI_SIG_MSCT, ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT,
 403         ACPI_SIG_ASF,  ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR,
 404         ACPI_SIG_HPET, ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG,
 405         ACPI_SIG_MCHI, ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI,
 406         ACPI_SIG_TCPA, ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT,
 407         ACPI_SIG_WDDT, ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT,
 408         ACPI_SIG_PSDT, ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT,
 409         ACPI_SIG_IORT, ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT,
 410         ACPI_SIG_NHLT, ACPI_SIG_AEST, ACPI_SIG_CEDT, ACPI_SIG_AGDI,
 411         ACPI_SIG_NBFT };
 412
 413 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
 414
 415 #define NR_ACPI_INITRD_TABLES 64
 416 static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
 417 static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
 418
 419 #define MAP_CHUNK_SIZE   (NR_FIX_BTMAPS << PAGE_SHIFT)
 420
 421 void __init acpi_table_upgrade(void)
 422 {
 423         void *data;
 424         size_t size;
 425         int sig, no, table_nr = 0, total_offset = 0;
 426         long offset = 0;
 427         struct acpi_table_header *table;
 428         char cpio_path[32] = "kernel/firmware/acpi/";
 429         struct cpio_data file;
 430
 431         if (IS_ENABLED(CONFIG_ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD)) {
 432                 data = __initramfs_start;
 433                 size = __initramfs_size;
 434         } else {
 435                 data = (void *)initrd_start;
 436                 size = initrd_end - initrd_start;
 437         }
 438
 439         if (data == NULL || size == 0)
 440                 return;
 441
 442         for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
 443                 file = find_cpio_data(cpio_path, data, size, &offset);
 444                 if (!file.data)
 445                         break;
 446
 447                 data += offset;
 448                 size -= offset;
 449
 450                 if (file.size < sizeof(struct acpi_table_header)) {
 451                         pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
 452                                 cpio_path, file.name);
 453                         continue;
 454                 }
 455
 456                 table = file.data;
 457
 458                 for (sig = 0; sig < ARRAY_SIZE(table_sigs); sig++)
 459                         if (!memcmp(table->signature, table_sigs[sig], 4))
 460                                 break;
 461
 462                 if (sig >= ARRAY_SIZE(table_sigs)) {
 463                         pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
 464                                 cpio_path, file.name);
 465                         continue;
 466                 }
 467                 if (file.size != table->length) {
 468                         pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
 469                                 cpio_path, file.name);
 470                         continue;
 471                 }
 472                 if (acpi_table_checksum(file.data, table->length)) {
 473                         pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
 474                                 cpio_path, file.name);
 475                         continue;
 476                 }
 477
 478                 pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
 479                         table->signature, cpio_path, file.name, table->length);
 480
 481                 all_tables_size += table->length;
 482                 acpi_initrd_files[table_nr].data = file.data;
 483                 acpi_initrd_files[table_nr].size = file.size;
 484                 table_nr++;
 485         }
 486         if (table_nr == 0)
 487                 return;
 488
 489         if (security_locked_down(LOCKDOWN_ACPI_TABLES)) {
 490                 pr_notice("kernel is locked down, ignoring table override\n");
 491                 return;
 492         }
 493
 494         acpi_tables_addr =
 495                 memblock_phys_alloc_range(all_tables_size, PAGE_SIZE,
 496                                           0, ACPI_TABLE_UPGRADE_MAX_PHYS);
 497         if (!acpi_tables_addr) {
 498                 WARN_ON(1);
 499                 return;
 500         }
 501         /*
 502          * Only calling e820_add_reserve does not work and the
 503          * tables are invalid (memory got used) later.
 504          * memblock_reserve works as expected and the tables won't get modified.
 505          * But it's not enough on X86 because ioremap will
 506          * complain later (used by acpi_os_map_memory) that the pages
 507          * that should get mapped are not marked "reserved".
 508          * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
 509          * works fine.
 510          */
 511         arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
 512
 513         kmemleak_ignore_phys(acpi_tables_addr);
 514
 515         /*
 516          * early_ioremap only can remap 256k one time. If we map all
 517          * tables one time, we will hit the limit. Need to map chunks
 518          * one by one during copying the same as that in relocate_initrd().
 519          */
 520         for (no = 0; no < table_nr; no++) {
 521                 unsigned char *src_p = acpi_initrd_files[no].data;
 522                 phys_addr_t size = acpi_initrd_files[no].size;
 523                 phys_addr_t dest_addr = acpi_tables_addr + total_offset;
 524                 phys_addr_t slop, clen;
 525                 char *dest_p;
 526
 527                 total_offset += size;
 528
 529                 while (size) {
 530                         slop = dest_addr & ~PAGE_MASK;
 531                         clen = size;
 532                         if (clen > MAP_CHUNK_SIZE - slop)
 533                                 clen = MAP_CHUNK_SIZE - slop;
 534                         dest_p = early_memremap(dest_addr & PAGE_MASK,
 535                                                 clen + slop);
 536                         memcpy(dest_p + slop, src_p, clen);
 537                         early_memunmap(dest_p, clen + slop);
 538                         src_p += clen;
 539                         dest_addr += clen;
 540                         size -= clen;
 541                 }
 542         }
 543 }
 544
 545 static acpi_status
 546 acpi_table_initrd_override(struct acpi_table_header *existing_table,
 547                            acpi_physical_address *address, u32 *length)
 548 {
 549         int table_offset = 0;
 550         int table_index = 0;
 551         struct acpi_table_header *table;
 552         u32 table_length;
 553
 554         *length = 0;
 555         *address = 0;
 556         if (!acpi_tables_addr)
 557                 return AE_OK;
 558
 559         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
 560                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
 561                                            ACPI_HEADER_SIZE);
 562                 if (table_offset + table->length > all_tables_size) {
 563                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 564                         WARN_ON(1);
 565                         return AE_OK;
 566                 }
 567
 568                 table_length = table->length;
 569
 570                 /* Only override tables matched */
 571                 if (memcmp(existing_table->signature, table->signature, 4) ||
 572                     memcmp(table->oem_id, existing_table->oem_id,
 573                            ACPI_OEM_ID_SIZE) ||
 574                     memcmp(table->oem_table_id, existing_table->oem_table_id,
 575                            ACPI_OEM_TABLE_ID_SIZE)) {
 576                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 577                         goto next_table;
 578                 }
 579                 /*
 580                  * Mark the table to avoid being used in
 581                  * acpi_table_initrd_scan() and check the revision.
 582                  */
 583                 if (test_and_set_bit(table_index, acpi_initrd_installed) ||
 584                     existing_table->oem_revision >= table->oem_revision) {
 585                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 586                         goto next_table;
 587                 }
 588
 589                 *length = table_length;
 590                 *address = acpi_tables_addr + table_offset;
 591                 pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
 592                         table->signature, table->oem_id,
 593                         table->oem_table_id);
 594                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 595                 break;
 596
 597 next_table:
 598                 table_offset += table_length;
 599                 table_index++;
 600         }
 601         return AE_OK;
 602 }
 603
 604 static void __init acpi_table_initrd_scan(void)
 605 {
 606         int table_offset = 0;
 607         int table_index = 0;
 608         u32 table_length;
 609         struct acpi_table_header *table;
 610
 611         if (!acpi_tables_addr)
 612                 return;
 613
 614         while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
 615                 table = acpi_os_map_memory(acpi_tables_addr + table_offset,
 616                                            ACPI_HEADER_SIZE);
 617                 if (table_offset + table->length > all_tables_size) {
 618                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 619                         WARN_ON(1);
 620                         return;
 621                 }
 622
 623                 table_length = table->length;
 624
 625                 /* Skip RSDT/XSDT which should only be used for override */
 626                 if (ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_RSDT) ||
 627                     ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_XSDT)) {
 628                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 629                         goto next_table;
 630                 }
 631                 /*
 632                  * Mark the table to avoid being used in
 633                  * acpi_table_initrd_override(). Though this is not possible
 634                  * because override is disabled in acpi_install_physical_table().
 635                  */
 636                 if (test_and_set_bit(table_index, acpi_initrd_installed)) {
 637                         acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 638                         goto next_table;
 639                 }
 640
 641                 pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
 642                         table->signature, table->oem_id,
 643                         table->oem_table_id);
 644                 acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 645                 acpi_install_physical_table(acpi_tables_addr + table_offset);
 646 next_table:
 647                 table_offset += table_length;
 648                 table_index++;
 649         }
 650 }
 651 #else
 652 static acpi_status
 653 acpi_table_initrd_override(struct acpi_table_header *existing_table,
 654                            acpi_physical_address *address,
 655                            u32 *table_length)
 656 {
 657         *table_length = 0;
 658         *address = 0;
 659         return AE_OK;
 660 }
 661
 662 static void __init acpi_table_initrd_scan(void)
 663 {
 664 }
 665 #endif /* CONFIG_ACPI_TABLE_UPGRADE */
 666
 667 acpi_status
 668 acpi_os_physical_table_override(struct acpi_table_header *existing_table,
 669                                 acpi_physical_address *address,
 670                                 u32 *table_length)
 671 {
 672         return acpi_table_initrd_override(existing_table, address,
 673                                           table_length);
 674 }
 675
 676 #ifdef CONFIG_ACPI_CUSTOM_DSDT
 677 static void *amlcode __attribute__ ((weakref("AmlCode")));
 678 static void *dsdt_amlcode __attribute__ ((weakref("dsdt_aml_code")));
 679 #endif
 680
 681 acpi_status acpi_os_table_override(struct acpi_table_header *existing_table,
 682                        struct acpi_table_header **new_table)
 683 {
 684         if (!existing_table || !new_table)
 685                 return AE_BAD_PARAMETER;
 686
 687         *new_table = NULL;
 688
 689 #ifdef CONFIG_ACPI_CUSTOM_DSDT
 690         if (!strncmp(existing_table->signature, "DSDT", 4)) {
 691                 *new_table = (struct acpi_table_header *)&amlcode;
 692                 if (!(*new_table))
 693                         *new_table = (struct acpi_table_header *)&dsdt_amlcode;
 694         }
 695 #endif
 696         if (*new_table != NULL)
 697                 acpi_table_taint(existing_table);
 698         return AE_OK;
 699 }
 700
 701 /*
 702  * acpi_locate_initial_tables()
 703  *
 704  * Get the RSDP, then find and checksum all the ACPI tables.
 705  *
 706  * result: initial_tables[] is initialized, and points to
 707  * a list of ACPI tables.
 708  */
 709 int __init acpi_locate_initial_tables(void)
 710 {
 711         acpi_status status;
 712
 713         if (acpi_verify_table_checksum) {
 714                 pr_info("Early table checksum verification enabled\n");
 715                 acpi_gbl_enable_table_validation = TRUE;
 716         } else {
 717                 pr_info("Early table checksum verification disabled\n");
 718                 acpi_gbl_enable_table_validation = FALSE;
 719         }
 720
 721         status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
 722         if (ACPI_FAILURE(status))
 723                 return -EINVAL;
 724
 725         return 0;
 726 }
 727
 728 void __init acpi_reserve_initial_tables(void)
 729 {
 730         int i;
 731
 732         for (i = 0; i < ACPI_MAX_TABLES; i++) {
 733                 struct acpi_table_desc *table_desc = &initial_tables[i];
 734                 u64 start = table_desc->address;
 735                 u64 size = table_desc->length;
 736
 737                 if (!start || !size)
 738                         break;
 739
 740                 pr_info("Reserving %4s table memory at [mem 0x%llx-0x%llx]\n",
 741                         table_desc->signature.ascii, start, start + size - 1);
 742
 743                 memblock_reserve(start, size);
 744         }
 745 }
 746
 747 void __init acpi_table_init_complete(void)
 748 {
 749         acpi_table_initrd_scan();
 750         check_multiple_madt();
 751 }
 752
 753 int __init acpi_table_init(void)
 754 {
 755         int ret;
 756
 757         ret = acpi_locate_initial_tables();
 758         if (ret)
 759                 return ret;
 760
 761         acpi_table_init_complete();
 762
 763         return 0;
 764 }
 765
 766 static int __init acpi_parse_apic_instance(char *str)
 767 {
 768         if (!str)
 769                 return -EINVAL;
 770
 771         if (kstrtoint(str, 0, &acpi_apic_instance))
 772                 return -EINVAL;
 773
 774         pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
 775
 776         return 0;
 777 }
 778 early_param("acpi_apic_instance", acpi_parse_apic_instance);
 779
 780 static int __init acpi_force_table_verification_setup(char *s)
 781 {
 782         acpi_verify_table_checksum = true;
 783
 784         return 0;
 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 early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);