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