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