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(const struct timespec *now)
 278 {
 279         unsigned long nowtime = now->tv_sec;
 280         efi_status_t    status;
 281         efi_time_t      eft;
 282         efi_time_cap_t  cap;
 283         struct rtc_time tm;
 284
 285         status = efi.get_time(&eft, &cap);
 286         if (status != EFI_SUCCESS) {
 287                 pr_err("Oops: efitime: can't read time!\n");
 288                 return -1;
 289         }
 290
 291         rtc_time_to_tm(nowtime, &tm);
 292         if (!rtc_valid_tm(&tm)) {
 293                 eft.year = tm.tm_year + 1900;
 294                 eft.month = tm.tm_mon + 1;
 295                 eft.day = tm.tm_mday;
 296                 eft.minute = tm.tm_min;
 297                 eft.second = tm.tm_sec;
 298                 eft.nanosecond = 0;
 299         } else {
 300                 printk(KERN_ERR
 301                        "%s: Invalid EFI RTC value: write of %lx to EFI RTC failed\n",
 302                        __FUNCTION__, nowtime);
 303                 return -1;
 304         }
 305
 306         status = efi.set_time(&eft);
 307         if (status != EFI_SUCCESS) {
 308                 pr_err("Oops: efitime: can't write time!\n");
 309                 return -1;
 310         }
 311         return 0;
 312 }
 313
 314 void efi_get_time(struct timespec *now)
 315 {
 316         efi_status_t status;
 317         efi_time_t eft;
 318         efi_time_cap_t cap;
 319
 320         status = efi.get_time(&eft, &cap);
 321         if (status != EFI_SUCCESS)
 322                 pr_err("Oops: efitime: can't read time!\n");
 323
 324         now->tv_sec = mktime(eft.year, eft.month, eft.day, eft.hour,
 325                              eft.minute, eft.second);
 326         now->tv_nsec = 0;
 327 }
 328
 329 /*
 330  * Tell the kernel about the EFI memory map.  This might include
 331  * more than the max 128 entries that can fit in the e820 legacy
 332  * (zeropage) memory map.
 333  */
 334
 335 static void __init do_add_efi_memmap(void)
 336 {
 337         void *p;
 338
 339         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 340                 efi_memory_desc_t *md = p;
 341                 unsigned long long start = md->phys_addr;
 342                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 343                 int e820_type;
 344
 345                 switch (md->type) {
 346                 case EFI_LOADER_CODE:
 347                 case EFI_LOADER_DATA:
 348                 case EFI_BOOT_SERVICES_CODE:
 349                 case EFI_BOOT_SERVICES_DATA:
 350                 case EFI_CONVENTIONAL_MEMORY:
 351                         if (md->attribute & EFI_MEMORY_WB)
 352                                 e820_type = E820_RAM;
 353                         else
 354                                 e820_type = E820_RESERVED;
 355                         break;
 356                 case EFI_ACPI_RECLAIM_MEMORY:
 357                         e820_type = E820_ACPI;
 358                         break;
 359                 case EFI_ACPI_MEMORY_NVS:
 360                         e820_type = E820_NVS;
 361                         break;
 362                 case EFI_UNUSABLE_MEMORY:
 363                         e820_type = E820_UNUSABLE;
 364                         break;
 365                 default:
 366                         /*
 367                          * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 368                          * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 369                          * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 370                          */
 371                         e820_type = E820_RESERVED;
 372                         break;
 373                 }
 374                 e820_add_region(start, size, e820_type);
 375         }
 376         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 377 }
 378
 379 int __init efi_memblock_x86_reserve_range(void)
 380 {
 381         struct efi_info *e = &boot_params.efi_info;
 382         unsigned long pmap;
 383
 384 #ifdef CONFIG_X86_32
 385         /* Can't handle data above 4GB at this time */
 386         if (e->efi_memmap_hi) {
 387                 pr_err("Memory map is above 4GB, disabling EFI.\n");
 388                 return -EINVAL;
 389         }
 390         pmap =  e->efi_memmap;
 391 #else
 392         pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
 393 #endif
 394         memmap.phys_map         = (void *)pmap;
 395         memmap.nr_map           = e->efi_memmap_size /
 396                                   e->efi_memdesc_size;
 397         memmap.desc_size        = e->efi_memdesc_size;
 398         memmap.desc_version     = e->efi_memdesc_version;
 399
 400         memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 401
 402         return 0;
 403 }
 404
 405 #if EFI_DEBUG
 406 static void __init print_efi_memmap(void)
 407 {
 408         efi_memory_desc_t *md;
 409         void *p;
 410         int i;
 411
 412         for (p = memmap.map, i = 0;
 413              p < memmap.map_end;
 414              p += memmap.desc_size, i++) {
 415                 md = p;
 416                 pr_info("mem%02u: type=%u, attr=0x%llx, "
 417                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 418                         i, md->type, md->attribute, md->phys_addr,
 419                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 420                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 421         }
 422 }
 423 #endif  /*  EFI_DEBUG  */
 424
 425 void __init efi_reserve_boot_services(void)
 426 {
 427         void *p;
 428
 429         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 430                 efi_memory_desc_t *md = p;
 431                 u64 start = md->phys_addr;
 432                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 433
 434                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 435                     md->type != EFI_BOOT_SERVICES_DATA)
 436                         continue;
 437                 /* Only reserve where possible:
 438                  * - Not within any already allocated areas
 439                  * - Not over any memory area (really needed, if above?)
 440                  * - Not within any part of the kernel
 441                  * - Not the bios reserved area
 442                 */
 443                 if ((start+size >= __pa_symbol(_text)
 444                                 && start <= __pa_symbol(_end)) ||
 445                         !e820_all_mapped(start, start+size, E820_RAM) ||
 446                         memblock_is_region_reserved(start, size)) {
 447                         /* Could not reserve, skip it */
 448                         md->num_pages = 0;
 449                         memblock_dbg("Could not reserve boot range "
 450                                         "[0x%010llx-0x%010llx]\n",
 451                                                 start, start+size-1);
 452                 } else
 453                         memblock_reserve(start, size);
 454         }
 455 }
 456
 457 void __init efi_unmap_memmap(void)
 458 {
 459         clear_bit(EFI_MEMMAP, &x86_efi_facility);
 460         if (memmap.map) {
 461                 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 462                 memmap.map = NULL;
 463         }
 464 }
 465
 466 void __init efi_free_boot_services(void)
 467 {
 468         void *p;
 469
 470         if (!efi_is_native())
 471                 return;
 472
 473         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 474                 efi_memory_desc_t *md = p;
 475                 unsigned long long start = md->phys_addr;
 476                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 477
 478                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 479                     md->type != EFI_BOOT_SERVICES_DATA)
 480                         continue;
 481
 482                 /* Could not reserve boot area */
 483                 if (!size)
 484                         continue;
 485
 486                 free_bootmem_late(start, size);
 487         }
 488
 489         efi_unmap_memmap();
 490 }
 491
 492 static int __init efi_systab_init(void *phys)
 493 {
 494         if (efi_enabled(EFI_64BIT)) {
 495                 efi_system_table_64_t *systab64;
 496                 u64 tmp = 0;
 497
 498                 systab64 = early_ioremap((unsigned long)phys,
 499                                          sizeof(*systab64));
 500                 if (systab64 == NULL) {
 501                         pr_err("Couldn't map the system table!\n");
 502                         return -ENOMEM;
 503                 }
 504
 505                 efi_systab.hdr = systab64->hdr;
 506                 efi_systab.fw_vendor = systab64->fw_vendor;
 507                 tmp |= systab64->fw_vendor;
 508                 efi_systab.fw_revision = systab64->fw_revision;
 509                 efi_systab.con_in_handle = systab64->con_in_handle;
 510                 tmp |= systab64->con_in_handle;
 511                 efi_systab.con_in = systab64->con_in;
 512                 tmp |= systab64->con_in;
 513                 efi_systab.con_out_handle = systab64->con_out_handle;
 514                 tmp |= systab64->con_out_handle;
 515                 efi_systab.con_out = systab64->con_out;
 516                 tmp |= systab64->con_out;
 517                 efi_systab.stderr_handle = systab64->stderr_handle;
 518                 tmp |= systab64->stderr_handle;
 519                 efi_systab.stderr = systab64->stderr;
 520                 tmp |= systab64->stderr;
 521                 efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
 522                 tmp |= systab64->runtime;
 523                 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
 524                 tmp |= systab64->boottime;
 525                 efi_systab.nr_tables = systab64->nr_tables;
 526                 efi_systab.tables = systab64->tables;
 527                 tmp |= systab64->tables;
 528
 529                 early_iounmap(systab64, sizeof(*systab64));
 530 #ifdef CONFIG_X86_32
 531                 if (tmp >> 32) {
 532                         pr_err("EFI data located above 4GB, disabling EFI.\n");
 533                         return -EINVAL;
 534                 }
 535 #endif
 536         } else {
 537                 efi_system_table_32_t *systab32;
 538
 539                 systab32 = early_ioremap((unsigned long)phys,
 540                                          sizeof(*systab32));
 541                 if (systab32 == NULL) {
 542                         pr_err("Couldn't map the system table!\n");
 543                         return -ENOMEM;
 544                 }
 545
 546                 efi_systab.hdr = systab32->hdr;
 547                 efi_systab.fw_vendor = systab32->fw_vendor;
 548                 efi_systab.fw_revision = systab32->fw_revision;
 549                 efi_systab.con_in_handle = systab32->con_in_handle;
 550                 efi_systab.con_in = systab32->con_in;
 551                 efi_systab.con_out_handle = systab32->con_out_handle;
 552                 efi_systab.con_out = systab32->con_out;
 553                 efi_systab.stderr_handle = systab32->stderr_handle;
 554                 efi_systab.stderr = systab32->stderr;
 555                 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
 556                 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
 557                 efi_systab.nr_tables = systab32->nr_tables;
 558                 efi_systab.tables = systab32->tables;
 559
 560                 early_iounmap(systab32, sizeof(*systab32));
 561         }
 562
 563         efi.systab = &efi_systab;
 564
 565         /*
 566          * Verify the EFI Table
 567          */
 568         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
 569                 pr_err("System table signature incorrect!\n");
 570                 return -EINVAL;
 571         }
 572         if ((efi.systab->hdr.revision >> 16) == 0)
 573                 pr_err("Warning: System table version "
 574                        "%d.%02d, expected 1.00 or greater!\n",
 575                        efi.systab->hdr.revision >> 16,
 576                        efi.systab->hdr.revision & 0xffff);
 577
 578         return 0;
 579 }
 580
 581 static int __init efi_config_init(u64 tables, int nr_tables)
 582 {
 583         void *config_tables, *tablep;
 584         int i, sz;
 585
 586         if (efi_enabled(EFI_64BIT))
 587                 sz = sizeof(efi_config_table_64_t);
 588         else
 589                 sz = sizeof(efi_config_table_32_t);
 590
 591         /*
 592          * Let's see what config tables the firmware passed to us.
 593          */
 594         config_tables = early_ioremap(tables, nr_tables * sz);
 595         if (config_tables == NULL) {
 596                 pr_err("Could not map Configuration table!\n");
 597                 return -ENOMEM;
 598         }
 599
 600         tablep = config_tables;
 601         pr_info("");
 602         for (i = 0; i < efi.systab->nr_tables; i++) {
 603                 efi_guid_t guid;
 604                 unsigned long table;
 605
 606                 if (efi_enabled(EFI_64BIT)) {
 607                         u64 table64;
 608                         guid = ((efi_config_table_64_t *)tablep)->guid;
 609                         table64 = ((efi_config_table_64_t *)tablep)->table;
 610                         table = table64;
 611 #ifdef CONFIG_X86_32
 612                         if (table64 >> 32) {
 613                                 pr_cont("\n");
 614                                 pr_err("Table located above 4GB, disabling EFI.\n");
 615                                 early_iounmap(config_tables,
 616                                               efi.systab->nr_tables * sz);
 617                                 return -EINVAL;
 618                         }
 619 #endif
 620                 } else {
 621                         guid = ((efi_config_table_32_t *)tablep)->guid;
 622                         table = ((efi_config_table_32_t *)tablep)->table;
 623                 }
 624                 if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
 625                         efi.mps = table;
 626                         pr_cont(" MPS=0x%lx ", table);
 627                 } else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
 628                         efi.acpi20 = table;
 629                         pr_cont(" ACPI 2.0=0x%lx ", table);
 630                 } else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
 631                         efi.acpi = table;
 632                         pr_cont(" ACPI=0x%lx ", table);
 633                 } else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
 634                         efi.smbios = table;
 635                         pr_cont(" SMBIOS=0x%lx ", table);
 636 #ifdef CONFIG_X86_UV
 637                 } else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
 638                         efi.uv_systab = table;
 639                         pr_cont(" UVsystab=0x%lx ", table);
 640 #endif
 641                 } else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
 642                         efi.hcdp = table;
 643                         pr_cont(" HCDP=0x%lx ", table);
 644                 } else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
 645                         efi.uga = table;
 646                         pr_cont(" UGA=0x%lx ", table);
 647                 }
 648                 tablep += sz;
 649         }
 650         pr_cont("\n");
 651         early_iounmap(config_tables, efi.systab->nr_tables * sz);
 652         return 0;
 653 }
 654
 655 static int __init efi_runtime_init(void)
 656 {
 657         efi_runtime_services_t *runtime;
 658
 659         /*
 660          * Check out the runtime services table. We need to map
 661          * the runtime services table so that we can grab the physical
 662          * address of several of the EFI runtime functions, needed to
 663          * set the firmware into virtual mode.
 664          */
 665         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 666                                 sizeof(efi_runtime_services_t));
 667         if (!runtime) {
 668                 pr_err("Could not map the runtime service table!\n");
 669                 return -ENOMEM;
 670         }
 671         /*
 672          * We will only need *early* access to the following
 673          * two EFI runtime services before set_virtual_address_map
 674          * is invoked.
 675          */
 676         efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 677         efi_phys.set_virtual_address_map =
 678                 (efi_set_virtual_address_map_t *)
 679                 runtime->set_virtual_address_map;
 680         /*
 681          * Make efi_get_time can be called before entering
 682          * virtual mode.
 683          */
 684         efi.get_time = phys_efi_get_time;
 685         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 686
 687         return 0;
 688 }
 689
 690 static int __init efi_memmap_init(void)
 691 {
 692         /* Map the EFI memory map */
 693         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 694                                    memmap.nr_map * memmap.desc_size);
 695         if (memmap.map == NULL) {
 696                 pr_err("Could not map the memory map!\n");
 697                 return -ENOMEM;
 698         }
 699         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 700
 701         if (add_efi_memmap)
 702                 do_add_efi_memmap();
 703
 704         return 0;
 705 }
 706
 707 void __init efi_init(void)
 708 {
 709         efi_char16_t *c16;
 710         char vendor[100] = "unknown";
 711         int i = 0;
 712         void *tmp;
 713
 714 #ifdef CONFIG_X86_32
 715         if (boot_params.efi_info.efi_systab_hi ||
 716             boot_params.efi_info.efi_memmap_hi) {
 717                 pr_info("Table located above 4GB, disabling EFI.\n");
 718                 return;
 719         }
 720         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 721 #else
 722         efi_phys.systab = (efi_system_table_t *)
 723                           (boot_params.efi_info.efi_systab |
 724                           ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 725 #endif
 726
 727         if (efi_systab_init(efi_phys.systab))
 728                 return;
 729
 730         set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
 731
 732         /*
 733          * Show what we know for posterity
 734          */
 735         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 736         if (c16) {
 737                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 738                         vendor[i] = *c16++;
 739                 vendor[i] = '\0';
 740         } else
 741                 pr_err("Could not map the firmware vendor!\n");
 742         early_iounmap(tmp, 2);
 743
 744         pr_info("EFI v%u.%.02u by %s\n",
 745                 efi.systab->hdr.revision >> 16,
 746                 efi.systab->hdr.revision & 0xffff, vendor);
 747
 748         if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
 749                 return;
 750
 751         set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
 752
 753         /*
 754          * Note: We currently don't support runtime services on an EFI
 755          * that doesn't match the kernel 32/64-bit mode.
 756          */
 757
 758         if (!efi_is_native())
 759                 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 760         else {
 761                 if (disable_runtime || efi_runtime_init())
 762                         return;
 763                 set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
 764         }
 765
 766         if (efi_memmap_init())
 767                 return;
 768
 769         set_bit(EFI_MEMMAP, &x86_efi_facility);
 770
 771 #ifdef CONFIG_X86_32
 772         if (efi_is_native()) {
 773                 x86_platform.get_wallclock = efi_get_time;
 774                 x86_platform.set_wallclock = efi_set_rtc_mmss;
 775         }
 776 #endif
 777
 778 #if EFI_DEBUG
 779         print_efi_memmap();
 780 #endif
 781 }
 782
 783 void __init efi_late_init(void)
 784 {
 785         efi_bgrt_init();
 786 }
 787
 788 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 789 {
 790         u64 addr, npages;
 791
 792         addr = md->virt_addr;
 793         npages = md->num_pages;
 794
 795         memrange_efi_to_native(&addr, &npages);
 796
 797         if (executable)
 798                 set_memory_x(addr, npages);
 799         else
 800                 set_memory_nx(addr, npages);
 801 }
 802
 803 static void __init runtime_code_page_mkexec(void)
 804 {
 805         efi_memory_desc_t *md;
 806         void *p;
 807
 808         /* Make EFI runtime service code area executable */
 809         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 810                 md = p;
 811
 812                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 813                         continue;
 814
 815                 efi_set_executable(md, true);
 816         }
 817 }
 818
 819 /*
 820  * We can't ioremap data in EFI boot services RAM, because we've already mapped
 821  * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
 822  * callable after efi_enter_virtual_mode and before efi_free_boot_services.
 823  */
 824 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
 825 {
 826         void *p;
 827         if (WARN_ON(!memmap.map))
 828                 return NULL;
 829         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 830                 efi_memory_desc_t *md = p;
 831                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 832                 u64 end = md->phys_addr + size;
 833                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 834                     md->type != EFI_BOOT_SERVICES_CODE &&
 835                     md->type != EFI_BOOT_SERVICES_DATA)
 836                         continue;
 837                 if (!md->virt_addr)
 838                         continue;
 839                 if (phys_addr >= md->phys_addr && phys_addr < end) {
 840                         phys_addr += md->virt_addr - md->phys_addr;
 841                         return (__force void __iomem *)(unsigned long)phys_addr;
 842                 }
 843         }
 844         return NULL;
 845 }
 846
 847 void efi_memory_uc(u64 addr, unsigned long size)
 848 {
 849         unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
 850         u64 npages;
 851
 852         npages = round_up(size, page_shift) / page_shift;
 853         memrange_efi_to_native(&addr, &npages);
 854         set_memory_uc(addr, npages);
 855 }
 856
 857 /*
 858  * This function will switch the EFI runtime services to virtual mode.
 859  * Essentially, look through the EFI memmap and map every region that
 860  * has the runtime attribute bit set in its memory descriptor and update
 861  * that memory descriptor with the virtual address obtained from ioremap().
 862  * This enables the runtime services to be called without having to
 863  * thunk back into physical mode for every invocation.
 864  */
 865 void __init efi_enter_virtual_mode(void)
 866 {
 867         efi_memory_desc_t *md, *prev_md = NULL;
 868         efi_status_t status;
 869         unsigned long size;
 870         u64 end, systab, start_pfn, end_pfn;
 871         void *p, *va, *new_memmap = NULL;
 872         int count = 0;
 873
 874         efi.systab = NULL;
 875
 876         /*
 877          * We don't do virtual mode, since we don't do runtime services, on
 878          * non-native EFI
 879          */
 880
 881         if (!efi_is_native()) {
 882                 efi_unmap_memmap();
 883                 return;
 884         }
 885
 886         /* Merge contiguous regions of the same type and attribute */
 887         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 888                 u64 prev_size;
 889                 md = p;
 890
 891                 if (!prev_md) {
 892                         prev_md = md;
 893                         continue;
 894                 }
 895
 896                 if (prev_md->type != md->type ||
 897                     prev_md->attribute != md->attribute) {
 898                         prev_md = md;
 899                         continue;
 900                 }
 901
 902                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 903
 904                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 905                         prev_md->num_pages += md->num_pages;
 906                         md->type = EFI_RESERVED_TYPE;
 907                         md->attribute = 0;
 908                         continue;
 909                 }
 910                 prev_md = md;
 911         }
 912
 913         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 914                 md = p;
 915                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 916                     md->type != EFI_BOOT_SERVICES_CODE &&
 917                     md->type != EFI_BOOT_SERVICES_DATA)
 918                         continue;
 919
 920                 size = md->num_pages << EFI_PAGE_SHIFT;
 921                 end = md->phys_addr + size;
 922
 923                 start_pfn = PFN_DOWN(md->phys_addr);
 924                 end_pfn = PFN_UP(end);
 925                 if (pfn_range_is_mapped(start_pfn, end_pfn)) {
 926                         va = __va(md->phys_addr);
 927
 928                         if (!(md->attribute & EFI_MEMORY_WB))
 929                                 efi_memory_uc((u64)(unsigned long)va, size);
 930                 } else
 931                         va = efi_ioremap(md->phys_addr, size,
 932                                          md->type, md->attribute);
 933
 934                 md->virt_addr = (u64) (unsigned long) va;
 935
 936                 if (!va) {
 937                         pr_err("ioremap of 0x%llX failed!\n",
 938                                (unsigned long long)md->phys_addr);
 939                         continue;
 940                 }
 941
 942                 systab = (u64) (unsigned long) efi_phys.systab;
 943                 if (md->phys_addr <= systab && systab < end) {
 944                         systab += md->virt_addr - md->phys_addr;
 945                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
 946                 }
 947                 new_memmap = krealloc(new_memmap,
 948                                       (count + 1) * memmap.desc_size,
 949                                       GFP_KERNEL);
 950                 memcpy(new_memmap + (count * memmap.desc_size), md,
 951                        memmap.desc_size);
 952                 count++;
 953         }
 954
 955         BUG_ON(!efi.systab);
 956
 957         status = phys_efi_set_virtual_address_map(
 958                 memmap.desc_size * count,
 959                 memmap.desc_size,
 960                 memmap.desc_version,
 961                 (efi_memory_desc_t *)__pa(new_memmap));
 962
 963         if (status != EFI_SUCCESS) {
 964                 pr_alert("Unable to switch EFI into virtual mode "
 965                          "(status=%lx)!\n", status);
 966                 panic("EFI call to SetVirtualAddressMap() failed!");
 967         }
 968
 969         /*
 970          * Now that EFI is in virtual mode, update the function
 971          * pointers in the runtime service table to the new virtual addresses.
 972          *
 973          * Call EFI services through wrapper functions.
 974          */
 975         efi.runtime_version = efi_systab.hdr.revision;
 976         efi.get_time = virt_efi_get_time;
 977         efi.set_time = virt_efi_set_time;
 978         efi.get_wakeup_time = virt_efi_get_wakeup_time;
 979         efi.set_wakeup_time = virt_efi_set_wakeup_time;
 980         efi.get_variable = virt_efi_get_variable;
 981         efi.get_next_variable = virt_efi_get_next_variable;
 982         efi.set_variable = virt_efi_set_variable;
 983         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
 984         efi.reset_system = virt_efi_reset_system;
 985         efi.set_virtual_address_map = NULL;
 986         efi.query_variable_info = virt_efi_query_variable_info;
 987         efi.update_capsule = virt_efi_update_capsule;
 988         efi.query_capsule_caps = virt_efi_query_capsule_caps;
 989         if (__supported_pte_mask & _PAGE_NX)
 990                 runtime_code_page_mkexec();
 991
 992         kfree(new_memmap);
 993
 994         /* clean DUMMY object */
 995         efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
 996                          EFI_VARIABLE_NON_VOLATILE |
 997                          EFI_VARIABLE_BOOTSERVICE_ACCESS |
 998                          EFI_VARIABLE_RUNTIME_ACCESS,
 999                          0, NULL);
1000 }
1001
1002 /*
1003  * Convenience functions to obtain memory types and attributes
1004  */
1005 u32 efi_mem_type(unsigned long phys_addr)
1006 {
1007         efi_memory_desc_t *md;
1008         void *p;
1009
1010         if (!efi_enabled(EFI_MEMMAP))
1011                 return 0;
1012
1013         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1014                 md = p;
1015                 if ((md->phys_addr <= phys_addr) &&
1016                     (phys_addr < (md->phys_addr +
1017                                   (md->num_pages << EFI_PAGE_SHIFT))))
1018                         return md->type;
1019         }
1020         return 0;
1021 }
1022
1023 u64 efi_mem_attributes(unsigned long phys_addr)
1024 {
1025         efi_memory_desc_t *md;
1026         void *p;
1027
1028         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1029                 md = p;
1030                 if ((md->phys_addr <= phys_addr) &&
1031                     (phys_addr < (md->phys_addr +
1032                                   (md->num_pages << EFI_PAGE_SHIFT))))
1033                         return md->attribute;
1034         }
1035         return 0;
1036 }
1037
1038 /*
1039  * Some firmware has serious problems when using more than 50% of the EFI
1040  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
1041  * we never use more than this safe limit.
1042  *
1043  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
1044  * store.
1045  */
1046 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
1047 {
1048         efi_status_t status;
1049         u64 storage_size, remaining_size, max_size;
1050
1051         if (!(attributes & EFI_VARIABLE_NON_VOLATILE))
1052                 return 0;
1053
1054         status = efi.query_variable_info(attributes, &storage_size,
1055                                          &remaining_size, &max_size);
1056         if (status != EFI_SUCCESS)
1057                 return status;
1058
1059         /*
1060          * Some firmware implementations refuse to boot if there's insufficient
1061          * space in the variable store. We account for that by refusing the
1062          * write if permitting it would reduce the available space to under
1063          * 5KB. This figure was provided by Samsung, so should be safe.
1064          */
1065         if ((remaining_size - size < EFI_MIN_RESERVE) &&
1066                 !efi_no_storage_paranoia) {
1067
1068                 /*
1069                  * Triggering garbage collection may require that the firmware
1070                  * generate a real EFI_OUT_OF_RESOURCES error. We can force
1071                  * that by attempting to use more space than is available.
1072                  */
1073                 unsigned long dummy_size = remaining_size + 1024;
1074                 void *dummy = kzalloc(dummy_size, GFP_ATOMIC);
1075
1076                 if (!dummy)
1077                         return EFI_OUT_OF_RESOURCES;
1078
1079                 status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
1080                                           EFI_VARIABLE_NON_VOLATILE |
1081                                           EFI_VARIABLE_BOOTSERVICE_ACCESS |
1082                                           EFI_VARIABLE_RUNTIME_ACCESS,
1083                                           dummy_size, dummy);
1084
1085                 if (status == EFI_SUCCESS) {
1086                         /*
1087                          * This should have failed, so if it didn't make sure
1088                          * that we delete it...
1089                          */
1090                         efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
1091                                          EFI_VARIABLE_NON_VOLATILE |
1092                                          EFI_VARIABLE_BOOTSERVICE_ACCESS |
1093                                          EFI_VARIABLE_RUNTIME_ACCESS,
1094                                          0, dummy);
1095                 }
1096
1097                 kfree(dummy);
1098
1099                 /*
1100                  * The runtime code may now have triggered a garbage collection
1101                  * run, so check the variable info again
1102                  */
1103                 status = efi.query_variable_info(attributes, &storage_size,
1104                                                  &remaining_size, &max_size);
1105
1106                 if (status != EFI_SUCCESS)
1107                         return status;
1108
1109                 /*
1110                  * There still isn't enough room, so return an error
1111                  */
1112                 if (remaining_size - size < EFI_MIN_RESERVE)
1113                         return EFI_OUT_OF_RESOURCES;
1114         }
1115
1116         return EFI_SUCCESS;
1117 }
1118 EXPORT_SYMBOL_GPL(efi_query_variable_store);