arch/x86/platform/efi/efi.c

   1 /*
   2  * Common EFI (Extensible Firmware Interface) support functions
   3  * Based on Extensible Firmware Interface Specification version 1.0
   4  *
   5  * Copyright (C) 1999 VA Linux Systems
   6  * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
   7  * Copyright (C) 1999-2002 Hewlett-Packard Co.
   8  *      David Mosberger-Tang <davidm@hpl.hp.com>
   9  *      Stephane Eranian <eranian@hpl.hp.com>
  10  * Copyright (C) 2005-2008 Intel Co.
  11  *      Fenghua Yu <fenghua.yu@intel.com>
  12  *      Bibo Mao <bibo.mao@intel.com>
  13  *      Chandramouli Narayanan <mouli@linux.intel.com>
  14  *      Huang Ying <ying.huang@intel.com>
  15  *
  16  * Copied from efi_32.c to eliminate the duplicated code between EFI
  17  * 32/64 support code. --ying 2007-10-26
  18  *
  19  * All EFI Runtime Services are not implemented yet as EFI only
  20  * supports physical mode addressing on SoftSDV. This is to be fixed
  21  * in a future version.  --drummond 1999-07-20
  22  *
  23  * Implemented EFI runtime services and virtual mode calls.  --davidm
  24  *
  25  * Goutham Rao: <goutham.rao@intel.com>
  26  *      Skip non-WB memory and ignore empty memory ranges.
  27  */
  28
  29 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  30
  31 #include <linux/kernel.h>
  32 #include <linux/init.h>
  33 #include <linux/efi.h>
  34 #include <linux/efi-bgrt.h>
  35 #include <linux/export.h>
  36 #include <linux/bootmem.h>
  37 #include <linux/slab.h>
  38 #include <linux/memblock.h>
  39 #include <linux/spinlock.h>
  40 #include <linux/uaccess.h>
  41 #include <linux/time.h>
  42 #include <linux/io.h>
  43 #include <linux/reboot.h>
  44 #include <linux/bcd.h>
  45
  46 #include <asm/setup.h>
  47 #include <asm/efi.h>
  48 #include <asm/time.h>
  49 #include <asm/cacheflush.h>
  50 #include <asm/tlbflush.h>
  51 #include <asm/x86_init.h>
  52 #include <asm/rtc.h>
  53
  54 #define EFI_DEBUG       1
  55
  56 #define EFI_MIN_RESERVE 5120
  57
  58 #define EFI_DUMMY_GUID \
  59         EFI_GUID(0x4424ac57, 0xbe4b, 0x47dd, 0x9e, 0x97, 0xed, 0x50, 0xf0, 0x9f, 0x92, 0xa9)
  60
  61 static efi_char16_t efi_dummy_name[6] = { 'D', 'U', 'M', 'M', 'Y', 0 };
  62
  63 struct efi __read_mostly efi = {
  64         .mps        = EFI_INVALID_TABLE_ADDR,
  65         .acpi       = EFI_INVALID_TABLE_ADDR,
  66         .acpi20     = EFI_INVALID_TABLE_ADDR,
  67         .smbios     = EFI_INVALID_TABLE_ADDR,
  68         .sal_systab = EFI_INVALID_TABLE_ADDR,
  69         .boot_info  = EFI_INVALID_TABLE_ADDR,
  70         .hcdp       = EFI_INVALID_TABLE_ADDR,
  71         .uga        = EFI_INVALID_TABLE_ADDR,
  72         .uv_systab  = EFI_INVALID_TABLE_ADDR,
  73 };
  74 EXPORT_SYMBOL(efi);
  75
  76 struct efi_memory_map memmap;
  77
  78 static struct efi efi_phys __initdata;
  79 static efi_system_table_t efi_systab __initdata;
  80
  81 unsigned long x86_efi_facility;
  82
  83 /*
  84  * Returns 1 if 'facility' is enabled, 0 otherwise.
  85  */
  86 int efi_enabled(int facility)
  87 {
  88         return test_bit(facility, &x86_efi_facility) != 0;
  89 }
  90 EXPORT_SYMBOL(efi_enabled);
  91
  92 static bool __initdata disable_runtime = false;
  93 static int __init setup_noefi(char *arg)
  94 {
  95         disable_runtime = true;
  96         return 0;
  97 }
  98 early_param("noefi", setup_noefi);
  99
 100 int add_efi_memmap;
 101 EXPORT_SYMBOL(add_efi_memmap);
 102
 103 static int __init setup_add_efi_memmap(char *arg)
 104 {
 105         add_efi_memmap = 1;
 106         return 0;
 107 }
 108 early_param("add_efi_memmap", setup_add_efi_memmap);
 109
 110 static bool efi_no_storage_paranoia;
 111
 112 static int __init setup_storage_paranoia(char *arg)
 113 {
 114         efi_no_storage_paranoia = true;
 115         return 0;
 116 }
 117 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
 118
 119
 120 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 121 {
 122         unsigned long flags;
 123         efi_status_t status;
 124
 125         spin_lock_irqsave(&rtc_lock, flags);
 126         status = efi_call_virt2(get_time, tm, tc);
 127         spin_unlock_irqrestore(&rtc_lock, flags);
 128         return status;
 129 }
 130
 131 static efi_status_t virt_efi_set_time(efi_time_t *tm)
 132 {
 133         unsigned long flags;
 134         efi_status_t status;
 135
 136         spin_lock_irqsave(&rtc_lock, flags);
 137         status = efi_call_virt1(set_time, tm);
 138         spin_unlock_irqrestore(&rtc_lock, flags);
 139         return status;
 140 }
 141
 142 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
 143                                              efi_bool_t *pending,
 144                                              efi_time_t *tm)
 145 {
 146         unsigned long flags;
 147         efi_status_t status;
 148
 149         spin_lock_irqsave(&rtc_lock, flags);
 150         status = efi_call_virt3(get_wakeup_time,
 151                                 enabled, pending, tm);
 152         spin_unlock_irqrestore(&rtc_lock, flags);
 153         return status;
 154 }
 155
 156 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
 157 {
 158         unsigned long flags;
 159         efi_status_t status;
 160
 161         spin_lock_irqsave(&rtc_lock, flags);
 162         status = efi_call_virt2(set_wakeup_time,
 163                                 enabled, tm);
 164         spin_unlock_irqrestore(&rtc_lock, flags);
 165         return status;
 166 }
 167
 168 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
 169                                           efi_guid_t *vendor,
 170                                           u32 *attr,
 171                                           unsigned long *data_size,
 172                                           void *data)
 173 {
 174         return efi_call_virt5(get_variable,
 175                               name, vendor, attr,
 176                               data_size, data);
 177 }
 178
 179 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 180                                                efi_char16_t *name,
 181                                                efi_guid_t *vendor)
 182 {
 183         return efi_call_virt3(get_next_variable,
 184                               name_size, name, vendor);
 185 }
 186
 187 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 188                                           efi_guid_t *vendor,
 189                                           u32 attr,
 190                                           unsigned long data_size,
 191                                           void *data)
 192 {
 193         return efi_call_virt5(set_variable,
 194                               name, vendor, attr,
 195                               data_size, data);
 196 }
 197
 198 static efi_status_t virt_efi_query_variable_info(u32 attr,
 199                                                  u64 *storage_space,
 200                                                  u64 *remaining_space,
 201                                                  u64 *max_variable_size)
 202 {
 203         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 204                 return EFI_UNSUPPORTED;
 205
 206         return efi_call_virt4(query_variable_info, attr, storage_space,
 207                               remaining_space, max_variable_size);
 208 }
 209
 210 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 211 {
 212         return efi_call_virt1(get_next_high_mono_count, count);
 213 }
 214
 215 static void virt_efi_reset_system(int reset_type,
 216                                   efi_status_t status,
 217                                   unsigned long data_size,
 218                                   efi_char16_t *data)
 219 {
 220         efi_call_virt4(reset_system, reset_type, status,
 221                        data_size, data);
 222 }
 223
 224 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
 225                                             unsigned long count,
 226                                             unsigned long sg_list)
 227 {
 228         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 229                 return EFI_UNSUPPORTED;
 230
 231         return efi_call_virt3(update_capsule, capsules, count, sg_list);
 232 }
 233
 234 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
 235                                                 unsigned long count,
 236                                                 u64 *max_size,
 237                                                 int *reset_type)
 238 {
 239         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 240                 return EFI_UNSUPPORTED;
 241
 242         return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
 243                               reset_type);
 244 }
 245
 246 static efi_status_t __init phys_efi_set_virtual_address_map(
 247         unsigned long memory_map_size,
 248         unsigned long descriptor_size,
 249         u32 descriptor_version,
 250         efi_memory_desc_t *virtual_map)
 251 {
 252         efi_status_t status;
 253
 254         efi_call_phys_prelog();
 255         status = efi_call_phys4(efi_phys.set_virtual_address_map,
 256                                 memory_map_size, descriptor_size,
 257                                 descriptor_version, virtual_map);
 258         efi_call_phys_epilog();
 259         return status;
 260 }
 261
 262 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
 263                                              efi_time_cap_t *tc)
 264 {
 265         unsigned long flags;
 266         efi_status_t status;
 267
 268         spin_lock_irqsave(&rtc_lock, flags);
 269         efi_call_phys_prelog();
 270         status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
 271                                 virt_to_phys(tc));
 272         efi_call_phys_epilog();
 273         spin_unlock_irqrestore(&rtc_lock, flags);
 274         return status;
 275 }
 276
 277 int efi_set_rtc_mmss(unsigned long nowtime)
 278 {
 279         efi_status_t    status;
 280         efi_time_t      eft;
 281         efi_time_cap_t  cap;
 282         struct rtc_time tm;
 283
 284         status = efi.get_time(&eft, &cap);
 285         if (status != EFI_SUCCESS) {
 286                 pr_err("Oops: efitime: can't read time!\n");
 287                 return -1;
 288         }
 289
 290         rtc_time_to_tm(nowtime, &tm);
 291         if (!rtc_valid_tm(&tm)) {
 292                 eft.year = tm.tm_year + 1900;
 293                 eft.month = tm.tm_mon + 1;
 294                 eft.day = tm.tm_mday;
 295                 eft.minute = tm.tm_min;
 296                 eft.second = tm.tm_sec;
 297                 eft.nanosecond = 0;
 298         } else {
 299                 printk(KERN_ERR
 300                        "%s: Invalid EFI RTC value: write of %lx to EFI RTC failed\n",
 301                        __FUNCTION__, nowtime);
 302                 return -1;
 303         }
 304
 305         status = efi.set_time(&eft);
 306         if (status != EFI_SUCCESS) {
 307                 pr_err("Oops: efitime: can't write time!\n");
 308                 return -1;
 309         }
 310         return 0;
 311 }
 312
 313 unsigned long efi_get_time(void)
 314 {
 315         efi_status_t status;
 316         efi_time_t eft;
 317         efi_time_cap_t cap;
 318
 319         status = efi.get_time(&eft, &cap);
 320         if (status != EFI_SUCCESS)
 321                 pr_err("Oops: efitime: can't read time!\n");
 322
 323         return mktime(eft.year, eft.month, eft.day, eft.hour,
 324                       eft.minute, eft.second);
 325 }
 326
 327 /*
 328  * Tell the kernel about the EFI memory map.  This might include
 329  * more than the max 128 entries that can fit in the e820 legacy
 330  * (zeropage) memory map.
 331  */
 332
 333 static void __init do_add_efi_memmap(void)
 334 {
 335         void *p;
 336
 337         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 338                 efi_memory_desc_t *md = p;
 339                 unsigned long long start = md->phys_addr;
 340                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 341                 int e820_type;
 342
 343                 switch (md->type) {
 344                 case EFI_LOADER_CODE:
 345                 case EFI_LOADER_DATA:
 346                 case EFI_BOOT_SERVICES_CODE:
 347                 case EFI_BOOT_SERVICES_DATA:
 348                 case EFI_CONVENTIONAL_MEMORY:
 349                         if (md->attribute & EFI_MEMORY_WB)
 350                                 e820_type = E820_RAM;
 351                         else
 352                                 e820_type = E820_RESERVED;
 353                         break;
 354                 case EFI_ACPI_RECLAIM_MEMORY:
 355                         e820_type = E820_ACPI;
 356                         break;
 357                 case EFI_ACPI_MEMORY_NVS:
 358                         e820_type = E820_NVS;
 359                         break;
 360                 case EFI_UNUSABLE_MEMORY:
 361                         e820_type = E820_UNUSABLE;
 362                         break;
 363                 default:
 364                         /*
 365                          * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 366                          * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 367                          * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 368                          */
 369                         e820_type = E820_RESERVED;
 370                         break;
 371                 }
 372                 e820_add_region(start, size, e820_type);
 373         }
 374         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 375 }
 376
 377 int __init efi_memblock_x86_reserve_range(void)
 378 {
 379         struct efi_info *e = &boot_params.efi_info;
 380         unsigned long pmap;
 381
 382 #ifdef CONFIG_X86_32
 383         /* Can't handle data above 4GB at this time */
 384         if (e->efi_memmap_hi) {
 385                 pr_err("Memory map is above 4GB, disabling EFI.\n");
 386                 return -EINVAL;
 387         }
 388         pmap =  e->efi_memmap;
 389 #else
 390         pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
 391 #endif
 392         memmap.phys_map         = (void *)pmap;
 393         memmap.nr_map           = e->efi_memmap_size /
 394                                   e->efi_memdesc_size;
 395         memmap.desc_size        = e->efi_memdesc_size;
 396         memmap.desc_version     = e->efi_memdesc_version;
 397
 398         memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 399
 400         return 0;
 401 }
 402
 403 #if EFI_DEBUG
 404 static void __init print_efi_memmap(void)
 405 {
 406         efi_memory_desc_t *md;
 407         void *p;
 408         int i;
 409
 410         for (p = memmap.map, i = 0;
 411              p < memmap.map_end;
 412              p += memmap.desc_size, i++) {
 413                 md = p;
 414                 pr_info("mem%02u: type=%u, attr=0x%llx, "
 415                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 416                         i, md->type, md->attribute, md->phys_addr,
 417                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 418                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 419         }
 420 }
 421 #endif  /*  EFI_DEBUG  */
 422
 423 void __init efi_reserve_boot_services(void)
 424 {
 425         void *p;
 426
 427         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 428                 efi_memory_desc_t *md = p;
 429                 u64 start = md->phys_addr;
 430                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 431
 432                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 433                     md->type != EFI_BOOT_SERVICES_DATA)
 434                         continue;
 435                 /* Only reserve where possible:
 436                  * - Not within any already allocated areas
 437                  * - Not over any memory area (really needed, if above?)
 438                  * - Not within any part of the kernel
 439                  * - Not the bios reserved area
 440                 */
 441                 if ((start + size > __pa_symbol(_text)
 442                                 && start <= __pa_symbol(_end)) ||
 443                         !e820_all_mapped(start, start+size, E820_RAM) ||
 444                         memblock_is_region_reserved(start, size)) {
 445                         /* Could not reserve, skip it */
 446                         md->num_pages = 0;
 447                         memblock_dbg("Could not reserve boot range "
 448                                         "[0x%010llx-0x%010llx]\n",
 449                                                 start, start+size-1);
 450                 } else
 451                         memblock_reserve(start, size);
 452         }
 453 }
 454
 455 void __init efi_unmap_memmap(void)
 456 {
 457         clear_bit(EFI_MEMMAP, &x86_efi_facility);
 458         if (memmap.map) {
 459                 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 460                 memmap.map = NULL;
 461         }
 462 }
 463
 464 void __init efi_free_boot_services(void)
 465 {
 466         void *p;
 467
 468         if (!efi_is_native())
 469                 return;
 470
 471         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 472                 efi_memory_desc_t *md = p;
 473                 unsigned long long start = md->phys_addr;
 474                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 475
 476                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 477                     md->type != EFI_BOOT_SERVICES_DATA)
 478                         continue;
 479
 480                 /* Could not reserve boot area */
 481                 if (!size)
 482                         continue;
 483
 484                 free_bootmem_late(start, size);
 485         }
 486
 487         efi_unmap_memmap();
 488 }
 489
 490 static int __init efi_systab_init(void *phys)
 491 {
 492         if (efi_enabled(EFI_64BIT)) {
 493                 efi_system_table_64_t *systab64;
 494                 u64 tmp = 0;
 495
 496                 systab64 = early_ioremap((unsigned long)phys,
 497                                          sizeof(*systab64));
 498                 if (systab64 == NULL) {
 499                         pr_err("Couldn't map the system table!\n");
 500                         return -ENOMEM;
 501                 }
 502
 503                 efi_systab.hdr = systab64->hdr;
 504                 efi_systab.fw_vendor = systab64->fw_vendor;
 505                 tmp |= systab64->fw_vendor;
 506                 efi_systab.fw_revision = systab64->fw_revision;
 507                 efi_systab.con_in_handle = systab64->con_in_handle;
 508                 tmp |= systab64->con_in_handle;
 509                 efi_systab.con_in = systab64->con_in;
 510                 tmp |= systab64->con_in;
 511                 efi_systab.con_out_handle = systab64->con_out_handle;
 512                 tmp |= systab64->con_out_handle;
 513                 efi_systab.con_out = systab64->con_out;
 514                 tmp |= systab64->con_out;
 515                 efi_systab.stderr_handle = systab64->stderr_handle;
 516                 tmp |= systab64->stderr_handle;
 517                 efi_systab.stderr = systab64->stderr;
 518                 tmp |= systab64->stderr;
 519                 efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
 520                 tmp |= systab64->runtime;
 521                 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
 522                 tmp |= systab64->boottime;
 523                 efi_systab.nr_tables = systab64->nr_tables;
 524                 efi_systab.tables = systab64->tables;
 525                 tmp |= systab64->tables;
 526
 527                 early_iounmap(systab64, sizeof(*systab64));
 528 #ifdef CONFIG_X86_32
 529                 if (tmp >> 32) {
 530                         pr_err("EFI data located above 4GB, disabling EFI.\n");
 531                         return -EINVAL;
 532                 }
 533 #endif
 534         } else {
 535                 efi_system_table_32_t *systab32;
 536
 537                 systab32 = early_ioremap((unsigned long)phys,
 538                                          sizeof(*systab32));
 539                 if (systab32 == NULL) {
 540                         pr_err("Couldn't map the system table!\n");
 541                         return -ENOMEM;
 542                 }
 543
 544                 efi_systab.hdr = systab32->hdr;
 545                 efi_systab.fw_vendor = systab32->fw_vendor;
 546                 efi_systab.fw_revision = systab32->fw_revision;
 547                 efi_systab.con_in_handle = systab32->con_in_handle;
 548                 efi_systab.con_in = systab32->con_in;
 549                 efi_systab.con_out_handle = systab32->con_out_handle;
 550                 efi_systab.con_out = systab32->con_out;
 551                 efi_systab.stderr_handle = systab32->stderr_handle;
 552                 efi_systab.stderr = systab32->stderr;
 553                 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
 554                 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
 555                 efi_systab.nr_tables = systab32->nr_tables;
 556                 efi_systab.tables = systab32->tables;
 557
 558                 early_iounmap(systab32, sizeof(*systab32));
 559         }
 560
 561         efi.systab = &efi_systab;
 562
 563         /*
 564          * Verify the EFI Table
 565          */
 566         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
 567                 pr_err("System table signature incorrect!\n");
 568                 return -EINVAL;
 569         }
 570         if ((efi.systab->hdr.revision >> 16) == 0)
 571                 pr_err("Warning: System table version "
 572                        "%d.%02d, expected 1.00 or greater!\n",
 573                        efi.systab->hdr.revision >> 16,
 574                        efi.systab->hdr.revision & 0xffff);
 575
 576         return 0;
 577 }
 578
 579 static int __init efi_config_init(u64 tables, int nr_tables)
 580 {
 581         void *config_tables, *tablep;
 582         int i, sz;
 583
 584         if (efi_enabled(EFI_64BIT))
 585                 sz = sizeof(efi_config_table_64_t);
 586         else
 587                 sz = sizeof(efi_config_table_32_t);
 588
 589         /*
 590          * Let's see what config tables the firmware passed to us.
 591          */
 592         config_tables = early_ioremap(tables, nr_tables * sz);
 593         if (config_tables == NULL) {
 594                 pr_err("Could not map Configuration table!\n");
 595                 return -ENOMEM;
 596         }
 597
 598         tablep = config_tables;
 599         pr_info("");
 600         for (i = 0; i < efi.systab->nr_tables; i++) {
 601                 efi_guid_t guid;
 602                 unsigned long table;
 603
 604                 if (efi_enabled(EFI_64BIT)) {
 605                         u64 table64;
 606                         guid = ((efi_config_table_64_t *)tablep)->guid;
 607                         table64 = ((efi_config_table_64_t *)tablep)->table;
 608                         table = table64;
 609 #ifdef CONFIG_X86_32
 610                         if (table64 >> 32) {
 611                                 pr_cont("\n");
 612                                 pr_err("Table located above 4GB, disabling EFI.\n");
 613                                 early_iounmap(config_tables,
 614                                               efi.systab->nr_tables * sz);
 615                                 return -EINVAL;
 616                         }
 617 #endif
 618                 } else {
 619                         guid = ((efi_config_table_32_t *)tablep)->guid;
 620                         table = ((efi_config_table_32_t *)tablep)->table;
 621                 }
 622                 if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
 623                         efi.mps = table;
 624                         pr_cont(" MPS=0x%lx ", table);
 625                 } else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
 626                         efi.acpi20 = table;
 627                         pr_cont(" ACPI 2.0=0x%lx ", table);
 628                 } else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
 629                         efi.acpi = table;
 630                         pr_cont(" ACPI=0x%lx ", table);
 631                 } else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
 632                         efi.smbios = table;
 633                         pr_cont(" SMBIOS=0x%lx ", table);
 634 #ifdef CONFIG_X86_UV
 635                 } else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
 636                         efi.uv_systab = table;
 637                         pr_cont(" UVsystab=0x%lx ", table);
 638 #endif
 639                 } else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
 640                         efi.hcdp = table;
 641                         pr_cont(" HCDP=0x%lx ", table);
 642                 } else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
 643                         efi.uga = table;
 644                         pr_cont(" UGA=0x%lx ", table);
 645                 }
 646                 tablep += sz;
 647         }
 648         pr_cont("\n");
 649         early_iounmap(config_tables, efi.systab->nr_tables * sz);
 650         return 0;
 651 }
 652
 653 static int __init efi_runtime_init(void)
 654 {
 655         efi_runtime_services_t *runtime;
 656
 657         /*
 658          * Check out the runtime services table. We need to map
 659          * the runtime services table so that we can grab the physical
 660          * address of several of the EFI runtime functions, needed to
 661          * set the firmware into virtual mode.
 662          */
 663         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 664                                 sizeof(efi_runtime_services_t));
 665         if (!runtime) {
 666                 pr_err("Could not map the runtime service table!\n");
 667                 return -ENOMEM;
 668         }
 669         /*
 670          * We will only need *early* access to the following
 671          * two EFI runtime services before set_virtual_address_map
 672          * is invoked.
 673          */
 674         efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 675         efi_phys.set_virtual_address_map =
 676                 (efi_set_virtual_address_map_t *)
 677                 runtime->set_virtual_address_map;
 678         /*
 679          * Make efi_get_time can be called before entering
 680          * virtual mode.
 681          */
 682         efi.get_time = phys_efi_get_time;
 683         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 684
 685         return 0;
 686 }
 687
 688 static int __init efi_memmap_init(void)
 689 {
 690         /* Map the EFI memory map */
 691         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 692                                    memmap.nr_map * memmap.desc_size);
 693         if (memmap.map == NULL) {
 694                 pr_err("Could not map the memory map!\n");
 695                 return -ENOMEM;
 696         }
 697         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 698
 699         if (add_efi_memmap)
 700                 do_add_efi_memmap();
 701
 702         return 0;
 703 }
 704
 705 void __init efi_init(void)
 706 {
 707         efi_char16_t *c16;
 708         char vendor[100] = "unknown";
 709         int i = 0;
 710         void *tmp;
 711
 712 #ifdef CONFIG_X86_32
 713         if (boot_params.efi_info.efi_systab_hi ||
 714             boot_params.efi_info.efi_memmap_hi) {
 715                 pr_info("Table located above 4GB, disabling EFI.\n");
 716                 return;
 717         }
 718         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 719 #else
 720         efi_phys.systab = (efi_system_table_t *)
 721                           (boot_params.efi_info.efi_systab |
 722                           ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 723 #endif
 724
 725         if (efi_systab_init(efi_phys.systab))
 726                 return;
 727
 728         set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
 729
 730         /*
 731          * Show what we know for posterity
 732          */
 733         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 734         if (c16) {
 735                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 736                         vendor[i] = *c16++;
 737                 vendor[i] = '\0';
 738         } else
 739                 pr_err("Could not map the firmware vendor!\n");
 740         early_iounmap(tmp, 2);
 741
 742         pr_info("EFI v%u.%.02u by %s\n",
 743                 efi.systab->hdr.revision >> 16,
 744                 efi.systab->hdr.revision & 0xffff, vendor);
 745
 746         if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
 747                 return;
 748
 749         set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
 750
 751         /*
 752          * Note: We currently don't support runtime services on an EFI
 753          * that doesn't match the kernel 32/64-bit mode.
 754          */
 755
 756         if (!efi_is_native())
 757                 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 758         else {
 759                 if (disable_runtime || efi_runtime_init())
 760                         return;
 761                 set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
 762         }
 763
 764         if (efi_memmap_init())
 765                 return;
 766
 767         set_bit(EFI_MEMMAP, &x86_efi_facility);
 768
 769 #if EFI_DEBUG
 770         print_efi_memmap();
 771 #endif
 772 }
 773
 774 void __init efi_late_init(void)
 775 {
 776         efi_bgrt_init();
 777 }
 778
 779 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 780 {
 781         u64 addr, npages;
 782
 783         addr = md->virt_addr;
 784         npages = md->num_pages;
 785
 786         memrange_efi_to_native(&addr, &npages);
 787
 788         if (executable)
 789                 set_memory_x(addr, npages);
 790         else
 791                 set_memory_nx(addr, npages);
 792 }
 793
 794 static void __init runtime_code_page_mkexec(void)
 795 {
 796         efi_memory_desc_t *md;
 797         void *p;
 798
 799         /* Make EFI runtime service code area executable */
 800         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 801                 md = p;
 802
 803                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 804                         continue;
 805
 806                 efi_set_executable(md, true);
 807         }
 808 }
 809
 810 /*
 811  * We can't ioremap data in EFI boot services RAM, because we've already mapped
 812  * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
 813  * callable after efi_enter_virtual_mode and before efi_free_boot_services.
 814  */
 815 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
 816 {
 817         void *p;
 818         if (WARN_ON(!memmap.map))
 819                 return NULL;
 820         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 821                 efi_memory_desc_t *md = p;
 822                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 823                 u64 end = md->phys_addr + size;
 824                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 825                     md->type != EFI_BOOT_SERVICES_CODE &&
 826                     md->type != EFI_BOOT_SERVICES_DATA)
 827                         continue;
 828                 if (!md->virt_addr)
 829                         continue;
 830                 if (phys_addr >= md->phys_addr && phys_addr < end) {
 831                         phys_addr += md->virt_addr - md->phys_addr;
 832                         return (__force void __iomem *)(unsigned long)phys_addr;
 833                 }
 834         }
 835         return NULL;
 836 }
 837
 838 void efi_memory_uc(u64 addr, unsigned long size)
 839 {
 840         unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
 841         u64 npages;
 842
 843         npages = round_up(size, page_shift) / page_shift;
 844         memrange_efi_to_native(&addr, &npages);
 845         set_memory_uc(addr, npages);
 846 }
 847
 848 /*
 849  * This function will switch the EFI runtime services to virtual mode.
 850  * Essentially, look through the EFI memmap and map every region that
 851  * has the runtime attribute bit set in its memory descriptor and update
 852  * that memory descriptor with the virtual address obtained from ioremap().
 853  * This enables the runtime services to be called without having to
 854  * thunk back into physical mode for every invocation.
 855  */
 856 void __init efi_enter_virtual_mode(void)
 857 {
 858         efi_memory_desc_t *md, *prev_md = NULL;
 859         efi_status_t status;
 860         unsigned long size;
 861         u64 end, systab, start_pfn, end_pfn;
 862         void *p, *va, *new_memmap = NULL;
 863         int count = 0;
 864
 865         efi.systab = NULL;
 866
 867         /*
 868          * We don't do virtual mode, since we don't do runtime services, on
 869          * non-native EFI
 870          */
 871
 872         if (!efi_is_native()) {
 873                 efi_unmap_memmap();
 874                 return;
 875         }
 876
 877         /* Merge contiguous regions of the same type and attribute */
 878         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 879                 u64 prev_size;
 880                 md = p;
 881
 882                 if (!prev_md) {
 883                         prev_md = md;
 884                         continue;
 885                 }
 886
 887                 if (prev_md->type != md->type ||
 888                     prev_md->attribute != md->attribute) {
 889                         prev_md = md;
 890                         continue;
 891                 }
 892
 893                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 894
 895                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 896                         prev_md->num_pages += md->num_pages;
 897                         md->type = EFI_RESERVED_TYPE;
 898                         md->attribute = 0;
 899                         continue;
 900                 }
 901                 prev_md = md;
 902         }
 903
 904         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 905                 md = p;
 906                 if (!(md->attribute & EFI_MEMORY_RUNTIME)) {
 907 #ifdef CONFIG_X86_64
 908                         if (md->type != EFI_BOOT_SERVICES_CODE &&
 909                             md->type != EFI_BOOT_SERVICES_DATA)
 910 #endif
 911                                 continue;
 912                 }
 913
 914                 size = md->num_pages << EFI_PAGE_SHIFT;
 915                 end = md->phys_addr + size;
 916
 917                 start_pfn = PFN_DOWN(md->phys_addr);
 918                 end_pfn = PFN_UP(end);
 919                 if (pfn_range_is_mapped(start_pfn, end_pfn)) {
 920                         va = __va(md->phys_addr);
 921
 922                         if (!(md->attribute & EFI_MEMORY_WB))
 923                                 efi_memory_uc((u64)(unsigned long)va, size);
 924                 } else
 925                         va = efi_ioremap(md->phys_addr, size,
 926                                          md->type, md->attribute);
 927
 928                 md->virt_addr = (u64) (unsigned long) va;
 929
 930                 if (!va) {
 931                         pr_err("ioremap of 0x%llX failed!\n",
 932                                (unsigned long long)md->phys_addr);
 933                         continue;
 934                 }
 935
 936                 systab = (u64) (unsigned long) efi_phys.systab;
 937                 if (md->phys_addr <= systab && systab < end) {
 938                         systab += md->virt_addr - md->phys_addr;
 939                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
 940                 }
 941                 new_memmap = krealloc(new_memmap,
 942                                       (count + 1) * memmap.desc_size,
 943                                       GFP_KERNEL);
 944                 memcpy(new_memmap + (count * memmap.desc_size), md,
 945                        memmap.desc_size);
 946                 count++;
 947         }
 948
 949         BUG_ON(!efi.systab);
 950
 951         status = phys_efi_set_virtual_address_map(
 952                 memmap.desc_size * count,
 953                 memmap.desc_size,
 954                 memmap.desc_version,
 955                 (efi_memory_desc_t *)__pa(new_memmap));
 956
 957         if (status != EFI_SUCCESS) {
 958                 pr_alert("Unable to switch EFI into virtual mode "
 959                          "(status=%lx)!\n", status);
 960                 panic("EFI call to SetVirtualAddressMap() failed!");
 961         }
 962
 963         /*
 964          * Now that EFI is in virtual mode, update the function
 965          * pointers in the runtime service table to the new virtual addresses.
 966          *
 967          * Call EFI services through wrapper functions.
 968          */
 969         efi.runtime_version = efi_systab.hdr.revision;
 970         efi.get_time = virt_efi_get_time;
 971         efi.set_time = virt_efi_set_time;
 972         efi.get_wakeup_time = virt_efi_get_wakeup_time;
 973         efi.set_wakeup_time = virt_efi_set_wakeup_time;
 974         efi.get_variable = virt_efi_get_variable;
 975         efi.get_next_variable = virt_efi_get_next_variable;
 976         efi.set_variable = virt_efi_set_variable;
 977         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
 978         efi.reset_system = virt_efi_reset_system;
 979         efi.set_virtual_address_map = NULL;
 980         efi.query_variable_info = virt_efi_query_variable_info;
 981         efi.update_capsule = virt_efi_update_capsule;
 982         efi.query_capsule_caps = virt_efi_query_capsule_caps;
 983         if (__supported_pte_mask & _PAGE_NX)
 984                 runtime_code_page_mkexec();
 985
 986         kfree(new_memmap);
 987
 988         /* clean DUMMY object */
 989         efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
 990                          EFI_VARIABLE_NON_VOLATILE |
 991                          EFI_VARIABLE_BOOTSERVICE_ACCESS |
 992                          EFI_VARIABLE_RUNTIME_ACCESS,
 993                          0, NULL);
 994 }
 995
 996 /*
 997  * Convenience functions to obtain memory types and attributes
 998  */
 999 u32 efi_mem_type(unsigned long phys_addr)
1000 {
1001         efi_memory_desc_t *md;
1002         void *p;
1003
1004         if (!efi_enabled(EFI_MEMMAP))
1005                 return 0;
1006
1007         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1008                 md = p;
1009                 if ((md->phys_addr <= phys_addr) &&
1010                     (phys_addr < (md->phys_addr +
1011                                   (md->num_pages << EFI_PAGE_SHIFT))))
1012                         return md->type;
1013         }
1014         return 0;
1015 }
1016
1017 u64 efi_mem_attributes(unsigned long phys_addr)
1018 {
1019         efi_memory_desc_t *md;
1020         void *p;
1021
1022         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1023                 md = p;
1024                 if ((md->phys_addr <= phys_addr) &&
1025                     (phys_addr < (md->phys_addr +
1026                                   (md->num_pages << EFI_PAGE_SHIFT))))
1027                         return md->attribute;
1028         }
1029         return 0;
1030 }
1031
1032 /*
1033  * Some firmware has serious problems when using more than 50% of the EFI
1034  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
1035  * we never use more than this safe limit.
1036  *
1037  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
1038  * store.
1039  */
1040 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
1041 {
1042         efi_status_t status;
1043         u64 storage_size, remaining_size, max_size;
1044
1045         if (!(attributes & EFI_VARIABLE_NON_VOLATILE))
1046                 return 0;
1047
1048         status = efi.query_variable_info(attributes, &storage_size,
1049                                          &remaining_size, &max_size);
1050         if (status != EFI_SUCCESS)
1051                 return status;
1052
1053         /*
1054          * Some firmware implementations refuse to boot if there's insufficient
1055          * space in the variable store. We account for that by refusing the
1056          * write if permitting it would reduce the available space to under
1057          * 5KB. This figure was provided by Samsung, so should be safe.
1058          */
1059         if ((remaining_size - size < EFI_MIN_RESERVE) &&
1060                 !efi_no_storage_paranoia) {
1061
1062                 /*
1063                  * Triggering garbage collection may require that the firmware
1064                  * generate a real EFI_OUT_OF_RESOURCES error. We can force
1065                  * that by attempting to use more space than is available.
1066                  */
1067                 unsigned long dummy_size = remaining_size + 1024;
1068                 void *dummy = kzalloc(dummy_size, GFP_ATOMIC);
1069
1070                 if (!dummy)
1071                         return EFI_OUT_OF_RESOURCES;
1072
1073                 status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
1074                                           EFI_VARIABLE_NON_VOLATILE |
1075                                           EFI_VARIABLE_BOOTSERVICE_ACCESS |
1076                                           EFI_VARIABLE_RUNTIME_ACCESS,
1077                                           dummy_size, dummy);
1078
1079                 if (status == EFI_SUCCESS) {
1080                         /*
1081                          * This should have failed, so if it didn't make sure
1082                          * that we delete it...
1083                          */
1084                         efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
1085                                          EFI_VARIABLE_NON_VOLATILE |
1086                                          EFI_VARIABLE_BOOTSERVICE_ACCESS |
1087                                          EFI_VARIABLE_RUNTIME_ACCESS,
1088                                          0, dummy);
1089                 }
1090
1091                 kfree(dummy);
1092
1093                 /*
1094                  * The runtime code may now have triggered a garbage collection
1095                  * run, so check the variable info again
1096                  */
1097                 status = efi.query_variable_info(attributes, &storage_size,
1098                                                  &remaining_size, &max_size);
1099
1100                 if (status != EFI_SUCCESS)
1101                         return status;
1102
1103                 /*
1104                  * There still isn't enough room, so return an error
1105                  */
1106                 if (remaining_size - size < EFI_MIN_RESERVE)
1107                         return EFI_OUT_OF_RESOURCES;
1108         }
1109
1110         return EFI_SUCCESS;
1111 }
1112 EXPORT_SYMBOL_GPL(efi_query_variable_store);