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/memblock.h>
  38 #include <linux/spinlock.h>
  39 #include <linux/uaccess.h>
  40 #include <linux/time.h>
  41 #include <linux/io.h>
  42 #include <linux/reboot.h>
  43 #include <linux/bcd.h>
  44 #include <linux/ucs2_string.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
  53 #define EFI_DEBUG       1
  54
  55 /*
  56  * There's some additional metadata associated with each
  57  * variable. Intel's reference implementation is 60 bytes - bump that
  58  * to account for potential alignment constraints
  59  */
  60 #define VAR_METADATA_SIZE 64
  61
  62 struct efi __read_mostly efi = {
  63         .mps        = EFI_INVALID_TABLE_ADDR,
  64         .acpi       = EFI_INVALID_TABLE_ADDR,
  65         .acpi20     = EFI_INVALID_TABLE_ADDR,
  66         .smbios     = EFI_INVALID_TABLE_ADDR,
  67         .sal_systab = EFI_INVALID_TABLE_ADDR,
  68         .boot_info  = EFI_INVALID_TABLE_ADDR,
  69         .hcdp       = EFI_INVALID_TABLE_ADDR,
  70         .uga        = EFI_INVALID_TABLE_ADDR,
  71         .uv_systab  = EFI_INVALID_TABLE_ADDR,
  72 };
  73 EXPORT_SYMBOL(efi);
  74
  75 struct efi_memory_map memmap;
  76
  77 static struct efi efi_phys __initdata;
  78 static efi_system_table_t efi_systab __initdata;
  79
  80 static u64 efi_var_store_size;
  81 static u64 efi_var_remaining_size;
  82 static u64 efi_var_max_var_size;
  83 static u64 boot_used_size;
  84 static u64 boot_var_size;
  85 static u64 active_size;
  86
  87 unsigned long x86_efi_facility;
  88
  89 /*
  90  * Returns 1 if 'facility' is enabled, 0 otherwise.
  91  */
  92 int efi_enabled(int facility)
  93 {
  94         return test_bit(facility, &x86_efi_facility) != 0;
  95 }
  96 EXPORT_SYMBOL(efi_enabled);
  97
  98 static bool __initdata disable_runtime = false;
  99 static int __init setup_noefi(char *arg)
 100 {
 101         disable_runtime = true;
 102         return 0;
 103 }
 104 early_param("noefi", setup_noefi);
 105
 106 int add_efi_memmap;
 107 EXPORT_SYMBOL(add_efi_memmap);
 108
 109 static int __init setup_add_efi_memmap(char *arg)
 110 {
 111         add_efi_memmap = 1;
 112         return 0;
 113 }
 114 early_param("add_efi_memmap", setup_add_efi_memmap);
 115
 116 static bool efi_no_storage_paranoia;
 117
 118 static int __init setup_storage_paranoia(char *arg)
 119 {
 120         efi_no_storage_paranoia = true;
 121         return 0;
 122 }
 123 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
 124
 125
 126 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 127 {
 128         unsigned long flags;
 129         efi_status_t status;
 130
 131         spin_lock_irqsave(&rtc_lock, flags);
 132         status = efi_call_virt2(get_time, tm, tc);
 133         spin_unlock_irqrestore(&rtc_lock, flags);
 134         return status;
 135 }
 136
 137 static efi_status_t virt_efi_set_time(efi_time_t *tm)
 138 {
 139         unsigned long flags;
 140         efi_status_t status;
 141
 142         spin_lock_irqsave(&rtc_lock, flags);
 143         status = efi_call_virt1(set_time, tm);
 144         spin_unlock_irqrestore(&rtc_lock, flags);
 145         return status;
 146 }
 147
 148 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
 149                                              efi_bool_t *pending,
 150                                              efi_time_t *tm)
 151 {
 152         unsigned long flags;
 153         efi_status_t status;
 154
 155         spin_lock_irqsave(&rtc_lock, flags);
 156         status = efi_call_virt3(get_wakeup_time,
 157                                 enabled, pending, tm);
 158         spin_unlock_irqrestore(&rtc_lock, flags);
 159         return status;
 160 }
 161
 162 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
 163 {
 164         unsigned long flags;
 165         efi_status_t status;
 166
 167         spin_lock_irqsave(&rtc_lock, flags);
 168         status = efi_call_virt2(set_wakeup_time,
 169                                 enabled, tm);
 170         spin_unlock_irqrestore(&rtc_lock, flags);
 171         return status;
 172 }
 173
 174 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
 175                                           efi_guid_t *vendor,
 176                                           u32 *attr,
 177                                           unsigned long *data_size,
 178                                           void *data)
 179 {
 180         return efi_call_virt5(get_variable,
 181                               name, vendor, attr,
 182                               data_size, data);
 183 }
 184
 185 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 186                                                efi_char16_t *name,
 187                                                efi_guid_t *vendor)
 188 {
 189         efi_status_t status;
 190         static bool finished = false;
 191         static u64 var_size;
 192
 193         status = efi_call_virt3(get_next_variable,
 194                                 name_size, name, vendor);
 195
 196         if (status == EFI_NOT_FOUND) {
 197                 finished = true;
 198                 if (var_size < boot_used_size) {
 199                         boot_var_size = boot_used_size - var_size;
 200                         active_size += boot_var_size;
 201                 } else {
 202                         printk(KERN_WARNING FW_BUG  "efi: Inconsistent initial sizes\n");
 203                 }
 204         }
 205
 206         if (boot_used_size && !finished) {
 207                 unsigned long size;
 208                 u32 attr;
 209                 efi_status_t s;
 210                 void *tmp;
 211
 212                 s = virt_efi_get_variable(name, vendor, &attr, &size, NULL);
 213
 214                 if (s != EFI_BUFFER_TOO_SMALL || !size)
 215                         return status;
 216
 217                 tmp = kmalloc(size, GFP_ATOMIC);
 218
 219                 if (!tmp)
 220                         return status;
 221
 222                 s = virt_efi_get_variable(name, vendor, &attr, &size, tmp);
 223
 224                 if (s == EFI_SUCCESS && (attr & EFI_VARIABLE_NON_VOLATILE)) {
 225                         var_size += size;
 226                         var_size += ucs2_strsize(name, 1024);
 227                         active_size += size;
 228                         active_size += VAR_METADATA_SIZE;
 229                         active_size += ucs2_strsize(name, 1024);
 230                 }
 231
 232                 kfree(tmp);
 233         }
 234
 235         return status;
 236 }
 237
 238 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 239                                           efi_guid_t *vendor,
 240                                           u32 attr,
 241                                           unsigned long data_size,
 242                                           void *data)
 243 {
 244         efi_status_t status;
 245         u32 orig_attr = 0;
 246         unsigned long orig_size = 0;
 247
 248         status = virt_efi_get_variable(name, vendor, &orig_attr, &orig_size,
 249                                        NULL);
 250
 251         if (status != EFI_BUFFER_TOO_SMALL)
 252                 orig_size = 0;
 253
 254         status = efi_call_virt5(set_variable,
 255                                 name, vendor, attr,
 256                                 data_size, data);
 257
 258         if (status == EFI_SUCCESS) {
 259                 if (orig_size) {
 260                         active_size -= orig_size;
 261                         active_size -= ucs2_strsize(name, 1024);
 262                         active_size -= VAR_METADATA_SIZE;
 263                 }
 264                 if (data_size) {
 265                         active_size += data_size;
 266                         active_size += ucs2_strsize(name, 1024);
 267                         active_size += VAR_METADATA_SIZE;
 268                 }
 269         }
 270
 271         return status;
 272 }
 273
 274 static efi_status_t virt_efi_query_variable_info(u32 attr,
 275                                                  u64 *storage_space,
 276                                                  u64 *remaining_space,
 277                                                  u64 *max_variable_size)
 278 {
 279         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 280                 return EFI_UNSUPPORTED;
 281
 282         return efi_call_virt4(query_variable_info, attr, storage_space,
 283                               remaining_space, max_variable_size);
 284 }
 285
 286 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 287 {
 288         return efi_call_virt1(get_next_high_mono_count, count);
 289 }
 290
 291 static void virt_efi_reset_system(int reset_type,
 292                                   efi_status_t status,
 293                                   unsigned long data_size,
 294                                   efi_char16_t *data)
 295 {
 296         efi_call_virt4(reset_system, reset_type, status,
 297                        data_size, data);
 298 }
 299
 300 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
 301                                             unsigned long count,
 302                                             unsigned long sg_list)
 303 {
 304         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 305                 return EFI_UNSUPPORTED;
 306
 307         return efi_call_virt3(update_capsule, capsules, count, sg_list);
 308 }
 309
 310 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
 311                                                 unsigned long count,
 312                                                 u64 *max_size,
 313                                                 int *reset_type)
 314 {
 315         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 316                 return EFI_UNSUPPORTED;
 317
 318         return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
 319                               reset_type);
 320 }
 321
 322 static efi_status_t __init phys_efi_set_virtual_address_map(
 323         unsigned long memory_map_size,
 324         unsigned long descriptor_size,
 325         u32 descriptor_version,
 326         efi_memory_desc_t *virtual_map)
 327 {
 328         efi_status_t status;
 329
 330         efi_call_phys_prelog();
 331         status = efi_call_phys4(efi_phys.set_virtual_address_map,
 332                                 memory_map_size, descriptor_size,
 333                                 descriptor_version, virtual_map);
 334         efi_call_phys_epilog();
 335         return status;
 336 }
 337
 338 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
 339                                              efi_time_cap_t *tc)
 340 {
 341         unsigned long flags;
 342         efi_status_t status;
 343
 344         spin_lock_irqsave(&rtc_lock, flags);
 345         efi_call_phys_prelog();
 346         status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
 347                                 virt_to_phys(tc));
 348         efi_call_phys_epilog();
 349         spin_unlock_irqrestore(&rtc_lock, flags);
 350         return status;
 351 }
 352
 353 int efi_set_rtc_mmss(unsigned long nowtime)
 354 {
 355         int real_seconds, real_minutes;
 356         efi_status_t    status;
 357         efi_time_t      eft;
 358         efi_time_cap_t  cap;
 359
 360         status = efi.get_time(&eft, &cap);
 361         if (status != EFI_SUCCESS) {
 362                 pr_err("Oops: efitime: can't read time!\n");
 363                 return -1;
 364         }
 365
 366         real_seconds = nowtime % 60;
 367         real_minutes = nowtime / 60;
 368         if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
 369                 real_minutes += 30;
 370         real_minutes %= 60;
 371         eft.minute = real_minutes;
 372         eft.second = real_seconds;
 373
 374         status = efi.set_time(&eft);
 375         if (status != EFI_SUCCESS) {
 376                 pr_err("Oops: efitime: can't write time!\n");
 377                 return -1;
 378         }
 379         return 0;
 380 }
 381
 382 unsigned long efi_get_time(void)
 383 {
 384         efi_status_t status;
 385         efi_time_t eft;
 386         efi_time_cap_t cap;
 387
 388         status = efi.get_time(&eft, &cap);
 389         if (status != EFI_SUCCESS)
 390                 pr_err("Oops: efitime: can't read time!\n");
 391
 392         return mktime(eft.year, eft.month, eft.day, eft.hour,
 393                       eft.minute, eft.second);
 394 }
 395
 396 /*
 397  * Tell the kernel about the EFI memory map.  This might include
 398  * more than the max 128 entries that can fit in the e820 legacy
 399  * (zeropage) memory map.
 400  */
 401
 402 static void __init do_add_efi_memmap(void)
 403 {
 404         void *p;
 405
 406         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 407                 efi_memory_desc_t *md = p;
 408                 unsigned long long start = md->phys_addr;
 409                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 410                 int e820_type;
 411
 412                 switch (md->type) {
 413                 case EFI_LOADER_CODE:
 414                 case EFI_LOADER_DATA:
 415                 case EFI_BOOT_SERVICES_CODE:
 416                 case EFI_BOOT_SERVICES_DATA:
 417                 case EFI_CONVENTIONAL_MEMORY:
 418                         if (md->attribute & EFI_MEMORY_WB)
 419                                 e820_type = E820_RAM;
 420                         else
 421                                 e820_type = E820_RESERVED;
 422                         break;
 423                 case EFI_ACPI_RECLAIM_MEMORY:
 424                         e820_type = E820_ACPI;
 425                         break;
 426                 case EFI_ACPI_MEMORY_NVS:
 427                         e820_type = E820_NVS;
 428                         break;
 429                 case EFI_UNUSABLE_MEMORY:
 430                         e820_type = E820_UNUSABLE;
 431                         break;
 432                 default:
 433                         /*
 434                          * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 435                          * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 436                          * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 437                          */
 438                         e820_type = E820_RESERVED;
 439                         break;
 440                 }
 441                 e820_add_region(start, size, e820_type);
 442         }
 443         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 444 }
 445
 446 int __init efi_memblock_x86_reserve_range(void)
 447 {
 448         unsigned long pmap;
 449
 450 #ifdef CONFIG_X86_32
 451         /* Can't handle data above 4GB at this time */
 452         if (boot_params.efi_info.efi_memmap_hi) {
 453                 pr_err("Memory map is above 4GB, disabling EFI.\n");
 454                 return -EINVAL;
 455         }
 456         pmap = boot_params.efi_info.efi_memmap;
 457 #else
 458         pmap = (boot_params.efi_info.efi_memmap |
 459                 ((__u64)boot_params.efi_info.efi_memmap_hi<<32));
 460 #endif
 461         memmap.phys_map = (void *)pmap;
 462         memmap.nr_map = boot_params.efi_info.efi_memmap_size /
 463                 boot_params.efi_info.efi_memdesc_size;
 464         memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
 465         memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
 466         memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 467
 468         return 0;
 469 }
 470
 471 #if EFI_DEBUG
 472 static void __init print_efi_memmap(void)
 473 {
 474         efi_memory_desc_t *md;
 475         void *p;
 476         int i;
 477
 478         for (p = memmap.map, i = 0;
 479              p < memmap.map_end;
 480              p += memmap.desc_size, i++) {
 481                 md = p;
 482                 pr_info("mem%02u: type=%u, attr=0x%llx, "
 483                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 484                         i, md->type, md->attribute, md->phys_addr,
 485                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 486                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 487         }
 488 }
 489 #endif  /*  EFI_DEBUG  */
 490
 491 void __init efi_reserve_boot_services(void)
 492 {
 493         void *p;
 494
 495         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 496                 efi_memory_desc_t *md = p;
 497                 u64 start = md->phys_addr;
 498                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 499
 500                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 501                     md->type != EFI_BOOT_SERVICES_DATA)
 502                         continue;
 503                 /* Only reserve where possible:
 504                  * - Not within any already allocated areas
 505                  * - Not over any memory area (really needed, if above?)
 506                  * - Not within any part of the kernel
 507                  * - Not the bios reserved area
 508                 */
 509                 if ((start+size >= __pa_symbol(_text)
 510                                 && start <= __pa_symbol(_end)) ||
 511                         !e820_all_mapped(start, start+size, E820_RAM) ||
 512                         memblock_is_region_reserved(start, size)) {
 513                         /* Could not reserve, skip it */
 514                         md->num_pages = 0;
 515                         memblock_dbg("Could not reserve boot range "
 516                                         "[0x%010llx-0x%010llx]\n",
 517                                                 start, start+size-1);
 518                 } else
 519                         memblock_reserve(start, size);
 520         }
 521 }
 522
 523 void __init efi_unmap_memmap(void)
 524 {
 525         clear_bit(EFI_MEMMAP, &x86_efi_facility);
 526         if (memmap.map) {
 527                 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 528                 memmap.map = NULL;
 529         }
 530 }
 531
 532 void __init efi_free_boot_services(void)
 533 {
 534         void *p;
 535
 536         if (!efi_is_native())
 537                 return;
 538
 539         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 540                 efi_memory_desc_t *md = p;
 541                 unsigned long long start = md->phys_addr;
 542                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 543
 544                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 545                     md->type != EFI_BOOT_SERVICES_DATA)
 546                         continue;
 547
 548                 /* Could not reserve boot area */
 549                 if (!size)
 550                         continue;
 551
 552                 free_bootmem_late(start, size);
 553         }
 554
 555         efi_unmap_memmap();
 556 }
 557
 558 static int __init efi_systab_init(void *phys)
 559 {
 560         if (efi_enabled(EFI_64BIT)) {
 561                 efi_system_table_64_t *systab64;
 562                 u64 tmp = 0;
 563
 564                 systab64 = early_ioremap((unsigned long)phys,
 565                                          sizeof(*systab64));
 566                 if (systab64 == NULL) {
 567                         pr_err("Couldn't map the system table!\n");
 568                         return -ENOMEM;
 569                 }
 570
 571                 efi_systab.hdr = systab64->hdr;
 572                 efi_systab.fw_vendor = systab64->fw_vendor;
 573                 tmp |= systab64->fw_vendor;
 574                 efi_systab.fw_revision = systab64->fw_revision;
 575                 efi_systab.con_in_handle = systab64->con_in_handle;
 576                 tmp |= systab64->con_in_handle;
 577                 efi_systab.con_in = systab64->con_in;
 578                 tmp |= systab64->con_in;
 579                 efi_systab.con_out_handle = systab64->con_out_handle;
 580                 tmp |= systab64->con_out_handle;
 581                 efi_systab.con_out = systab64->con_out;
 582                 tmp |= systab64->con_out;
 583                 efi_systab.stderr_handle = systab64->stderr_handle;
 584                 tmp |= systab64->stderr_handle;
 585                 efi_systab.stderr = systab64->stderr;
 586                 tmp |= systab64->stderr;
 587                 efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
 588                 tmp |= systab64->runtime;
 589                 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
 590                 tmp |= systab64->boottime;
 591                 efi_systab.nr_tables = systab64->nr_tables;
 592                 efi_systab.tables = systab64->tables;
 593                 tmp |= systab64->tables;
 594
 595                 early_iounmap(systab64, sizeof(*systab64));
 596 #ifdef CONFIG_X86_32
 597                 if (tmp >> 32) {
 598                         pr_err("EFI data located above 4GB, disabling EFI.\n");
 599                         return -EINVAL;
 600                 }
 601 #endif
 602         } else {
 603                 efi_system_table_32_t *systab32;
 604
 605                 systab32 = early_ioremap((unsigned long)phys,
 606                                          sizeof(*systab32));
 607                 if (systab32 == NULL) {
 608                         pr_err("Couldn't map the system table!\n");
 609                         return -ENOMEM;
 610                 }
 611
 612                 efi_systab.hdr = systab32->hdr;
 613                 efi_systab.fw_vendor = systab32->fw_vendor;
 614                 efi_systab.fw_revision = systab32->fw_revision;
 615                 efi_systab.con_in_handle = systab32->con_in_handle;
 616                 efi_systab.con_in = systab32->con_in;
 617                 efi_systab.con_out_handle = systab32->con_out_handle;
 618                 efi_systab.con_out = systab32->con_out;
 619                 efi_systab.stderr_handle = systab32->stderr_handle;
 620                 efi_systab.stderr = systab32->stderr;
 621                 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
 622                 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
 623                 efi_systab.nr_tables = systab32->nr_tables;
 624                 efi_systab.tables = systab32->tables;
 625
 626                 early_iounmap(systab32, sizeof(*systab32));
 627         }
 628
 629         efi.systab = &efi_systab;
 630
 631         /*
 632          * Verify the EFI Table
 633          */
 634         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
 635                 pr_err("System table signature incorrect!\n");
 636                 return -EINVAL;
 637         }
 638         if ((efi.systab->hdr.revision >> 16) == 0)
 639                 pr_err("Warning: System table version "
 640                        "%d.%02d, expected 1.00 or greater!\n",
 641                        efi.systab->hdr.revision >> 16,
 642                        efi.systab->hdr.revision & 0xffff);
 643
 644         return 0;
 645 }
 646
 647 static int __init efi_config_init(u64 tables, int nr_tables)
 648 {
 649         void *config_tables, *tablep;
 650         int i, sz;
 651
 652         if (efi_enabled(EFI_64BIT))
 653                 sz = sizeof(efi_config_table_64_t);
 654         else
 655                 sz = sizeof(efi_config_table_32_t);
 656
 657         /*
 658          * Let's see what config tables the firmware passed to us.
 659          */
 660         config_tables = early_ioremap(tables, nr_tables * sz);
 661         if (config_tables == NULL) {
 662                 pr_err("Could not map Configuration table!\n");
 663                 return -ENOMEM;
 664         }
 665
 666         tablep = config_tables;
 667         pr_info("");
 668         for (i = 0; i < efi.systab->nr_tables; i++) {
 669                 efi_guid_t guid;
 670                 unsigned long table;
 671
 672                 if (efi_enabled(EFI_64BIT)) {
 673                         u64 table64;
 674                         guid = ((efi_config_table_64_t *)tablep)->guid;
 675                         table64 = ((efi_config_table_64_t *)tablep)->table;
 676                         table = table64;
 677 #ifdef CONFIG_X86_32
 678                         if (table64 >> 32) {
 679                                 pr_cont("\n");
 680                                 pr_err("Table located above 4GB, disabling EFI.\n");
 681                                 early_iounmap(config_tables,
 682                                               efi.systab->nr_tables * sz);
 683                                 return -EINVAL;
 684                         }
 685 #endif
 686                 } else {
 687                         guid = ((efi_config_table_32_t *)tablep)->guid;
 688                         table = ((efi_config_table_32_t *)tablep)->table;
 689                 }
 690                 if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
 691                         efi.mps = table;
 692                         pr_cont(" MPS=0x%lx ", table);
 693                 } else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
 694                         efi.acpi20 = table;
 695                         pr_cont(" ACPI 2.0=0x%lx ", table);
 696                 } else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
 697                         efi.acpi = table;
 698                         pr_cont(" ACPI=0x%lx ", table);
 699                 } else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
 700                         efi.smbios = table;
 701                         pr_cont(" SMBIOS=0x%lx ", table);
 702 #ifdef CONFIG_X86_UV
 703                 } else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
 704                         efi.uv_systab = table;
 705                         pr_cont(" UVsystab=0x%lx ", table);
 706 #endif
 707                 } else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
 708                         efi.hcdp = table;
 709                         pr_cont(" HCDP=0x%lx ", table);
 710                 } else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
 711                         efi.uga = table;
 712                         pr_cont(" UGA=0x%lx ", table);
 713                 }
 714                 tablep += sz;
 715         }
 716         pr_cont("\n");
 717         early_iounmap(config_tables, efi.systab->nr_tables * sz);
 718         return 0;
 719 }
 720
 721 static int __init efi_runtime_init(void)
 722 {
 723         efi_runtime_services_t *runtime;
 724
 725         /*
 726          * Check out the runtime services table. We need to map
 727          * the runtime services table so that we can grab the physical
 728          * address of several of the EFI runtime functions, needed to
 729          * set the firmware into virtual mode.
 730          */
 731         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 732                                 sizeof(efi_runtime_services_t));
 733         if (!runtime) {
 734                 pr_err("Could not map the runtime service table!\n");
 735                 return -ENOMEM;
 736         }
 737         /*
 738          * We will only need *early* access to the following
 739          * two EFI runtime services before set_virtual_address_map
 740          * is invoked.
 741          */
 742         efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 743         efi_phys.set_virtual_address_map =
 744                 (efi_set_virtual_address_map_t *)
 745                 runtime->set_virtual_address_map;
 746         /*
 747          * Make efi_get_time can be called before entering
 748          * virtual mode.
 749          */
 750         efi.get_time = phys_efi_get_time;
 751         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 752
 753         return 0;
 754 }
 755
 756 static int __init efi_memmap_init(void)
 757 {
 758         /* Map the EFI memory map */
 759         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 760                                    memmap.nr_map * memmap.desc_size);
 761         if (memmap.map == NULL) {
 762                 pr_err("Could not map the memory map!\n");
 763                 return -ENOMEM;
 764         }
 765         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 766
 767         if (add_efi_memmap)
 768                 do_add_efi_memmap();
 769
 770         return 0;
 771 }
 772
 773 void __init efi_init(void)
 774 {
 775         efi_char16_t *c16;
 776         char vendor[100] = "unknown";
 777         int i = 0;
 778         void *tmp;
 779         struct setup_data *data;
 780         struct efi_var_bootdata *efi_var_data;
 781         u64 pa_data;
 782
 783 #ifdef CONFIG_X86_32
 784         if (boot_params.efi_info.efi_systab_hi ||
 785             boot_params.efi_info.efi_memmap_hi) {
 786                 pr_info("Table located above 4GB, disabling EFI.\n");
 787                 return;
 788         }
 789         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 790 #else
 791         efi_phys.systab = (efi_system_table_t *)
 792                           (boot_params.efi_info.efi_systab |
 793                           ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 794 #endif
 795
 796         if (efi_systab_init(efi_phys.systab))
 797                 return;
 798
 799         pa_data = boot_params.hdr.setup_data;
 800         while (pa_data) {
 801                 data = early_ioremap(pa_data, sizeof(*efi_var_data));
 802                 if (data->type == SETUP_EFI_VARS) {
 803                         efi_var_data = (struct efi_var_bootdata *)data;
 804
 805                         efi_var_store_size = efi_var_data->store_size;
 806                         efi_var_remaining_size = efi_var_data->remaining_size;
 807                         efi_var_max_var_size = efi_var_data->max_var_size;
 808                 }
 809                 pa_data = data->next;
 810                 early_iounmap(data, sizeof(*efi_var_data));
 811         }
 812
 813         boot_used_size = efi_var_store_size - efi_var_remaining_size;
 814
 815         set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
 816
 817         /*
 818          * Show what we know for posterity
 819          */
 820         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 821         if (c16) {
 822                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 823                         vendor[i] = *c16++;
 824                 vendor[i] = '\0';
 825         } else
 826                 pr_err("Could not map the firmware vendor!\n");
 827         early_iounmap(tmp, 2);
 828
 829         pr_info("EFI v%u.%.02u by %s\n",
 830                 efi.systab->hdr.revision >> 16,
 831                 efi.systab->hdr.revision & 0xffff, vendor);
 832
 833         if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
 834                 return;
 835
 836         set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
 837
 838         /*
 839          * Note: We currently don't support runtime services on an EFI
 840          * that doesn't match the kernel 32/64-bit mode.
 841          */
 842
 843         if (!efi_is_native())
 844                 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 845         else {
 846                 if (disable_runtime || efi_runtime_init())
 847                         return;
 848                 set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
 849         }
 850
 851         if (efi_memmap_init())
 852                 return;
 853
 854         set_bit(EFI_MEMMAP, &x86_efi_facility);
 855
 856 #ifdef CONFIG_X86_32
 857         if (efi_is_native()) {
 858                 x86_platform.get_wallclock = efi_get_time;
 859                 x86_platform.set_wallclock = efi_set_rtc_mmss;
 860         }
 861 #endif
 862
 863 #if EFI_DEBUG
 864         print_efi_memmap();
 865 #endif
 866 }
 867
 868 void __init efi_late_init(void)
 869 {
 870         efi_bgrt_init();
 871 }
 872
 873 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 874 {
 875         u64 addr, npages;
 876
 877         addr = md->virt_addr;
 878         npages = md->num_pages;
 879
 880         memrange_efi_to_native(&addr, &npages);
 881
 882         if (executable)
 883                 set_memory_x(addr, npages);
 884         else
 885                 set_memory_nx(addr, npages);
 886 }
 887
 888 static void __init runtime_code_page_mkexec(void)
 889 {
 890         efi_memory_desc_t *md;
 891         void *p;
 892
 893         /* Make EFI runtime service code area executable */
 894         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 895                 md = p;
 896
 897                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 898                         continue;
 899
 900                 efi_set_executable(md, true);
 901         }
 902 }
 903
 904 /*
 905  * We can't ioremap data in EFI boot services RAM, because we've already mapped
 906  * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
 907  * callable after efi_enter_virtual_mode and before efi_free_boot_services.
 908  */
 909 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
 910 {
 911         void *p;
 912         if (WARN_ON(!memmap.map))
 913                 return NULL;
 914         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 915                 efi_memory_desc_t *md = p;
 916                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 917                 u64 end = md->phys_addr + size;
 918                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 919                     md->type != EFI_BOOT_SERVICES_CODE &&
 920                     md->type != EFI_BOOT_SERVICES_DATA)
 921                         continue;
 922                 if (!md->virt_addr)
 923                         continue;
 924                 if (phys_addr >= md->phys_addr && phys_addr < end) {
 925                         phys_addr += md->virt_addr - md->phys_addr;
 926                         return (__force void __iomem *)(unsigned long)phys_addr;
 927                 }
 928         }
 929         return NULL;
 930 }
 931
 932 void efi_memory_uc(u64 addr, unsigned long size)
 933 {
 934         unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
 935         u64 npages;
 936
 937         npages = round_up(size, page_shift) / page_shift;
 938         memrange_efi_to_native(&addr, &npages);
 939         set_memory_uc(addr, npages);
 940 }
 941
 942 /*
 943  * This function will switch the EFI runtime services to virtual mode.
 944  * Essentially, look through the EFI memmap and map every region that
 945  * has the runtime attribute bit set in its memory descriptor and update
 946  * that memory descriptor with the virtual address obtained from ioremap().
 947  * This enables the runtime services to be called without having to
 948  * thunk back into physical mode for every invocation.
 949  */
 950 void __init efi_enter_virtual_mode(void)
 951 {
 952         efi_memory_desc_t *md, *prev_md = NULL;
 953         efi_status_t status;
 954         unsigned long size;
 955         u64 end, systab, start_pfn, end_pfn;
 956         void *p, *va, *new_memmap = NULL;
 957         int count = 0;
 958
 959         efi.systab = NULL;
 960
 961         /*
 962          * We don't do virtual mode, since we don't do runtime services, on
 963          * non-native EFI
 964          */
 965
 966         if (!efi_is_native()) {
 967                 efi_unmap_memmap();
 968                 return;
 969         }
 970
 971         /* Merge contiguous regions of the same type and attribute */
 972         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 973                 u64 prev_size;
 974                 md = p;
 975
 976                 if (!prev_md) {
 977                         prev_md = md;
 978                         continue;
 979                 }
 980
 981                 if (prev_md->type != md->type ||
 982                     prev_md->attribute != md->attribute) {
 983                         prev_md = md;
 984                         continue;
 985                 }
 986
 987                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 988
 989                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 990                         prev_md->num_pages += md->num_pages;
 991                         md->type = EFI_RESERVED_TYPE;
 992                         md->attribute = 0;
 993                         continue;
 994                 }
 995                 prev_md = md;
 996         }
 997
 998         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 999                 md = p;
1000                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
1001                     md->type != EFI_BOOT_SERVICES_CODE &&
1002                     md->type != EFI_BOOT_SERVICES_DATA)
1003                         continue;
1004
1005                 size = md->num_pages << EFI_PAGE_SHIFT;
1006                 end = md->phys_addr + size;
1007
1008                 start_pfn = PFN_DOWN(md->phys_addr);
1009                 end_pfn = PFN_UP(end);
1010                 if (pfn_range_is_mapped(start_pfn, end_pfn)) {
1011                         va = __va(md->phys_addr);
1012
1013                         if (!(md->attribute & EFI_MEMORY_WB))
1014                                 efi_memory_uc((u64)(unsigned long)va, size);
1015                 } else
1016                         va = efi_ioremap(md->phys_addr, size,
1017                                          md->type, md->attribute);
1018
1019                 md->virt_addr = (u64) (unsigned long) va;
1020
1021                 if (!va) {
1022                         pr_err("ioremap of 0x%llX failed!\n",
1023                                (unsigned long long)md->phys_addr);
1024                         continue;
1025                 }
1026
1027                 systab = (u64) (unsigned long) efi_phys.systab;
1028                 if (md->phys_addr <= systab && systab < end) {
1029                         systab += md->virt_addr - md->phys_addr;
1030                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
1031                 }
1032                 new_memmap = krealloc(new_memmap,
1033                                       (count + 1) * memmap.desc_size,
1034                                       GFP_KERNEL);
1035                 memcpy(new_memmap + (count * memmap.desc_size), md,
1036                        memmap.desc_size);
1037                 count++;
1038         }
1039
1040         BUG_ON(!efi.systab);
1041
1042         status = phys_efi_set_virtual_address_map(
1043                 memmap.desc_size * count,
1044                 memmap.desc_size,
1045                 memmap.desc_version,
1046                 (efi_memory_desc_t *)__pa(new_memmap));
1047
1048         if (status != EFI_SUCCESS) {
1049                 pr_alert("Unable to switch EFI into virtual mode "
1050                          "(status=%lx)!\n", status);
1051                 panic("EFI call to SetVirtualAddressMap() failed!");
1052         }
1053
1054         /*
1055          * Now that EFI is in virtual mode, update the function
1056          * pointers in the runtime service table to the new virtual addresses.
1057          *
1058          * Call EFI services through wrapper functions.
1059          */
1060         efi.runtime_version = efi_systab.hdr.revision;
1061         efi.get_time = virt_efi_get_time;
1062         efi.set_time = virt_efi_set_time;
1063         efi.get_wakeup_time = virt_efi_get_wakeup_time;
1064         efi.set_wakeup_time = virt_efi_set_wakeup_time;
1065         efi.get_variable = virt_efi_get_variable;
1066         efi.get_next_variable = virt_efi_get_next_variable;
1067         efi.set_variable = virt_efi_set_variable;
1068         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
1069         efi.reset_system = virt_efi_reset_system;
1070         efi.set_virtual_address_map = NULL;
1071         efi.query_variable_info = virt_efi_query_variable_info;
1072         efi.update_capsule = virt_efi_update_capsule;
1073         efi.query_capsule_caps = virt_efi_query_capsule_caps;
1074         if (__supported_pte_mask & _PAGE_NX)
1075                 runtime_code_page_mkexec();
1076
1077         kfree(new_memmap);
1078 }
1079
1080 /*
1081  * Convenience functions to obtain memory types and attributes
1082  */
1083 u32 efi_mem_type(unsigned long phys_addr)
1084 {
1085         efi_memory_desc_t *md;
1086         void *p;
1087
1088         if (!efi_enabled(EFI_MEMMAP))
1089                 return 0;
1090
1091         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1092                 md = p;
1093                 if ((md->phys_addr <= phys_addr) &&
1094                     (phys_addr < (md->phys_addr +
1095                                   (md->num_pages << EFI_PAGE_SHIFT))))
1096                         return md->type;
1097         }
1098         return 0;
1099 }
1100
1101 u64 efi_mem_attributes(unsigned long phys_addr)
1102 {
1103         efi_memory_desc_t *md;
1104         void *p;
1105
1106         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1107                 md = p;
1108                 if ((md->phys_addr <= phys_addr) &&
1109                     (phys_addr < (md->phys_addr +
1110                                   (md->num_pages << EFI_PAGE_SHIFT))))
1111                         return md->attribute;
1112         }
1113         return 0;
1114 }
1115
1116 /*
1117  * Some firmware has serious problems when using more than 50% of the EFI
1118  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
1119  * we never use more than this safe limit.
1120  *
1121  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
1122  * store.
1123  */
1124 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
1125 {
1126         efi_status_t status;
1127         u64 storage_size, remaining_size, max_size;
1128
1129         status = efi.query_variable_info(attributes, &storage_size,
1130                                          &remaining_size, &max_size);
1131         if (status != EFI_SUCCESS)
1132                 return status;
1133
1134         if (!max_size && remaining_size > size)
1135                 printk_once(KERN_ERR FW_BUG "Broken EFI implementation"
1136                             " is returning MaxVariableSize=0\n");
1137         /*
1138          * Some firmware implementations refuse to boot if there's insufficient
1139          * space in the variable store. We account for that by refusing the
1140          * write if permitting it would reduce the available space to under
1141          * 50%. However, some firmware won't reclaim variable space until
1142          * after the used (not merely the actively used) space drops below
1143          * a threshold. We can approximate that case with the value calculated
1144          * above. If both the firmware and our calculations indicate that the
1145          * available space would drop below 50%, refuse the write.
1146          */
1147
1148         if (!storage_size || size > remaining_size ||
1149             (max_size && size > max_size))
1150                 return EFI_OUT_OF_RESOURCES;
1151
1152         if (!efi_no_storage_paranoia &&
1153             ((active_size + size + VAR_METADATA_SIZE > storage_size / 2) &&
1154              (remaining_size - size < storage_size / 2)))
1155                 return EFI_OUT_OF_RESOURCES;
1156
1157         return EFI_SUCCESS;
1158 }
1159 EXPORT_SYMBOL_GPL(efi_query_variable_store);