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 #include <linux/kernel.h>
  30 #include <linux/init.h>
  31 #include <linux/efi.h>
  32 #include <linux/export.h>
  33 #include <linux/bootmem.h>
  34 #include <linux/memblock.h>
  35 #include <linux/spinlock.h>
  36 #include <linux/uaccess.h>
  37 #include <linux/time.h>
  38 #include <linux/io.h>
  39 #include <linux/reboot.h>
  40 #include <linux/bcd.h>
  41
  42 #include <asm/setup.h>
  43 #include <asm/efi.h>
  44 #include <asm/time.h>
  45 #include <asm/cacheflush.h>
  46 #include <asm/tlbflush.h>
  47 #include <asm/x86_init.h>
  48
  49 #define EFI_DEBUG       1
  50 #define PFX             "EFI: "
  51
  52 struct efi __read_mostly efi = {
  53         .mps        = EFI_INVALID_TABLE_ADDR,
  54         .acpi       = EFI_INVALID_TABLE_ADDR,
  55         .acpi20     = EFI_INVALID_TABLE_ADDR,
  56         .smbios     = EFI_INVALID_TABLE_ADDR,
  57         .sal_systab = EFI_INVALID_TABLE_ADDR,
  58         .boot_info  = EFI_INVALID_TABLE_ADDR,
  59         .hcdp       = EFI_INVALID_TABLE_ADDR,
  60         .uga        = EFI_INVALID_TABLE_ADDR,
  61         .uv_systab  = EFI_INVALID_TABLE_ADDR,
  62 };
  63 EXPORT_SYMBOL(efi);
  64
  65 struct efi_memory_map memmap;
  66
  67 static struct efi efi_phys __initdata;
  68 static efi_system_table_t efi_systab __initdata;
  69
  70 static inline bool efi_is_native(void)
  71 {
  72         return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
  73 }
  74
  75 unsigned long x86_efi_facility;
  76
  77 /*
  78  * Returns 1 if 'facility' is enabled, 0 otherwise.
  79  */
  80 int efi_enabled(int facility)
  81 {
  82         return test_bit(facility, &x86_efi_facility) != 0;
  83 }
  84 EXPORT_SYMBOL(efi_enabled);
  85
  86 static bool disable_runtime = false;
  87 static int __init setup_noefi(char *arg)
  88 {
  89         disable_runtime = true;
  90         return 0;
  91 }
  92 early_param("noefi", setup_noefi);
  93
  94 int add_efi_memmap;
  95 EXPORT_SYMBOL(add_efi_memmap);
  96
  97 static int __init setup_add_efi_memmap(char *arg)
  98 {
  99         add_efi_memmap = 1;
 100         return 0;
 101 }
 102 early_param("add_efi_memmap", setup_add_efi_memmap);
 103
 104 static bool efi_no_storage_paranoia;
 105
 106 static int __init setup_storage_paranoia(char *arg)
 107 {
 108         efi_no_storage_paranoia = true;
 109         return 0;
 110 }
 111 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
 112
 113
 114 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 115 {
 116         unsigned long flags;
 117         efi_status_t status;
 118
 119         spin_lock_irqsave(&rtc_lock, flags);
 120         status = efi_call_virt2(get_time, tm, tc);
 121         spin_unlock_irqrestore(&rtc_lock, flags);
 122         return status;
 123 }
 124
 125 static efi_status_t virt_efi_set_time(efi_time_t *tm)
 126 {
 127         unsigned long flags;
 128         efi_status_t status;
 129
 130         spin_lock_irqsave(&rtc_lock, flags);
 131         status = efi_call_virt1(set_time, tm);
 132         spin_unlock_irqrestore(&rtc_lock, flags);
 133         return status;
 134 }
 135
 136 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
 137                                              efi_bool_t *pending,
 138                                              efi_time_t *tm)
 139 {
 140         unsigned long flags;
 141         efi_status_t status;
 142
 143         spin_lock_irqsave(&rtc_lock, flags);
 144         status = efi_call_virt3(get_wakeup_time,
 145                                 enabled, pending, tm);
 146         spin_unlock_irqrestore(&rtc_lock, flags);
 147         return status;
 148 }
 149
 150 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, 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_virt2(set_wakeup_time,
 157                                 enabled, tm);
 158         spin_unlock_irqrestore(&rtc_lock, flags);
 159         return status;
 160 }
 161
 162 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
 163                                           efi_guid_t *vendor,
 164                                           u32 *attr,
 165                                           unsigned long *data_size,
 166                                           void *data)
 167 {
 168         return efi_call_virt5(get_variable,
 169                               name, vendor, attr,
 170                               data_size, data);
 171 }
 172
 173 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 174                                                efi_char16_t *name,
 175                                                efi_guid_t *vendor)
 176 {
 177         return efi_call_virt3(get_next_variable,
 178                               name_size, name, vendor);
 179 }
 180
 181 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 182                                           efi_guid_t *vendor,
 183                                           u32 attr,
 184                                           unsigned long data_size,
 185                                           void *data)
 186 {
 187         return efi_call_virt5(set_variable,
 188                               name, vendor, attr,
 189                               data_size, data);
 190 }
 191
 192 static efi_status_t virt_efi_query_variable_info(u32 attr,
 193                                                  u64 *storage_space,
 194                                                  u64 *remaining_space,
 195                                                  u64 *max_variable_size)
 196 {
 197         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 198                 return EFI_UNSUPPORTED;
 199
 200         return efi_call_virt4(query_variable_info, attr, storage_space,
 201                               remaining_space, max_variable_size);
 202 }
 203
 204 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 205 {
 206         return efi_call_virt1(get_next_high_mono_count, count);
 207 }
 208
 209 static void virt_efi_reset_system(int reset_type,
 210                                   efi_status_t status,
 211                                   unsigned long data_size,
 212                                   efi_char16_t *data)
 213 {
 214         efi_call_virt4(reset_system, reset_type, status,
 215                        data_size, data);
 216 }
 217
 218 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
 219                                             unsigned long count,
 220                                             unsigned long sg_list)
 221 {
 222         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 223                 return EFI_UNSUPPORTED;
 224
 225         return efi_call_virt3(update_capsule, capsules, count, sg_list);
 226 }
 227
 228 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
 229                                                 unsigned long count,
 230                                                 u64 *max_size,
 231                                                 int *reset_type)
 232 {
 233         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 234                 return EFI_UNSUPPORTED;
 235
 236         return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
 237                               reset_type);
 238 }
 239
 240 static efi_status_t __init phys_efi_set_virtual_address_map(
 241         unsigned long memory_map_size,
 242         unsigned long descriptor_size,
 243         u32 descriptor_version,
 244         efi_memory_desc_t *virtual_map)
 245 {
 246         efi_status_t status;
 247
 248         efi_call_phys_prelog();
 249         status = efi_call_phys4(efi_phys.set_virtual_address_map,
 250                                 memory_map_size, descriptor_size,
 251                                 descriptor_version, virtual_map);
 252         efi_call_phys_epilog();
 253         return status;
 254 }
 255
 256 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
 257                                              efi_time_cap_t *tc)
 258 {
 259         unsigned long flags;
 260         efi_status_t status;
 261
 262         spin_lock_irqsave(&rtc_lock, flags);
 263         efi_call_phys_prelog();
 264         status = efi_call_phys2(efi_phys.get_time, tm, tc);
 265         efi_call_phys_epilog();
 266         spin_unlock_irqrestore(&rtc_lock, flags);
 267         return status;
 268 }
 269
 270 int efi_set_rtc_mmss(unsigned long nowtime)
 271 {
 272         int real_seconds, real_minutes;
 273         efi_status_t    status;
 274         efi_time_t      eft;
 275         efi_time_cap_t  cap;
 276
 277         status = efi.get_time(&eft, &cap);
 278         if (status != EFI_SUCCESS) {
 279                 printk(KERN_ERR "Oops: efitime: can't read time!\n");
 280                 return -1;
 281         }
 282
 283         real_seconds = nowtime % 60;
 284         real_minutes = nowtime / 60;
 285         if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
 286                 real_minutes += 30;
 287         real_minutes %= 60;
 288         eft.minute = real_minutes;
 289         eft.second = real_seconds;
 290
 291         status = efi.set_time(&eft);
 292         if (status != EFI_SUCCESS) {
 293                 printk(KERN_ERR "Oops: efitime: can't write time!\n");
 294                 return -1;
 295         }
 296         return 0;
 297 }
 298
 299 unsigned long efi_get_time(void)
 300 {
 301         efi_status_t status;
 302         efi_time_t eft;
 303         efi_time_cap_t cap;
 304
 305         status = efi.get_time(&eft, &cap);
 306         if (status != EFI_SUCCESS)
 307                 printk(KERN_ERR "Oops: efitime: can't read time!\n");
 308
 309         return mktime(eft.year, eft.month, eft.day, eft.hour,
 310                       eft.minute, eft.second);
 311 }
 312
 313 /*
 314  * Tell the kernel about the EFI memory map.  This might include
 315  * more than the max 128 entries that can fit in the e820 legacy
 316  * (zeropage) memory map.
 317  */
 318
 319 static void __init do_add_efi_memmap(void)
 320 {
 321         void *p;
 322
 323         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 324                 efi_memory_desc_t *md = p;
 325                 unsigned long long start = md->phys_addr;
 326                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 327                 int e820_type;
 328
 329                 switch (md->type) {
 330                 case EFI_LOADER_CODE:
 331                 case EFI_LOADER_DATA:
 332                 case EFI_BOOT_SERVICES_CODE:
 333                 case EFI_BOOT_SERVICES_DATA:
 334                 case EFI_CONVENTIONAL_MEMORY:
 335                         if (md->attribute & EFI_MEMORY_WB)
 336                                 e820_type = E820_RAM;
 337                         else
 338                                 e820_type = E820_RESERVED;
 339                         break;
 340                 case EFI_ACPI_RECLAIM_MEMORY:
 341                         e820_type = E820_ACPI;
 342                         break;
 343                 case EFI_ACPI_MEMORY_NVS:
 344                         e820_type = E820_NVS;
 345                         break;
 346                 case EFI_UNUSABLE_MEMORY:
 347                         e820_type = E820_UNUSABLE;
 348                         break;
 349                 default:
 350                         /*
 351                          * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 352                          * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 353                          * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 354                          */
 355                         e820_type = E820_RESERVED;
 356                         break;
 357                 }
 358                 e820_add_region(start, size, e820_type);
 359         }
 360         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 361 }
 362
 363 void __init efi_memblock_x86_reserve_range(void)
 364 {
 365         unsigned long pmap;
 366
 367 #ifdef CONFIG_X86_32
 368         pmap = boot_params.efi_info.efi_memmap;
 369 #else
 370         pmap = (boot_params.efi_info.efi_memmap |
 371                 ((__u64)boot_params.efi_info.efi_memmap_hi<<32));
 372 #endif
 373         memmap.phys_map = (void *)pmap;
 374         memmap.nr_map = boot_params.efi_info.efi_memmap_size /
 375                 boot_params.efi_info.efi_memdesc_size;
 376         memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
 377         memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
 378         memblock_x86_reserve_range(pmap, pmap + memmap.nr_map * memmap.desc_size,
 379                       "EFI memmap");
 380 }
 381
 382 #if EFI_DEBUG
 383 static void __init print_efi_memmap(void)
 384 {
 385         efi_memory_desc_t *md;
 386         void *p;
 387         int i;
 388
 389         for (p = memmap.map, i = 0;
 390              p < memmap.map_end;
 391              p += memmap.desc_size, i++) {
 392                 md = p;
 393                 printk(KERN_INFO PFX "mem%02u: type=%u, attr=0x%llx, "
 394                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 395                         i, md->type, md->attribute, md->phys_addr,
 396                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 397                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 398         }
 399 }
 400 #endif  /*  EFI_DEBUG  */
 401
 402 void __init efi_reserve_boot_services(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                 u64 start = md->phys_addr;
 409                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 410
 411                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 412                     md->type != EFI_BOOT_SERVICES_DATA)
 413                         continue;
 414                 /* Only reserve where possible:
 415                  * - Not within any already allocated areas
 416                  * - Not over any memory area (really needed, if above?)
 417                  * - Not within any part of the kernel
 418                  * - Not the bios reserved area
 419                 */
 420                 if ((start+size >= virt_to_phys(_text)
 421                                 && start <= virt_to_phys(_end)) ||
 422                         !e820_all_mapped(start, start+size, E820_RAM) ||
 423                         memblock_x86_check_reserved_size(&start, &size,
 424                                                         1<<EFI_PAGE_SHIFT)) {
 425                         /* Could not reserve, skip it */
 426                         md->num_pages = 0;
 427                         memblock_dbg(PFX "Could not reserve boot range "
 428                                         "[0x%010llx-0x%010llx]\n",
 429                                                 start, start+size-1);
 430                 } else
 431                         memblock_x86_reserve_range(start, start+size,
 432                                                         "EFI Boot");
 433         }
 434 }
 435
 436 static void __init efi_free_boot_services(void)
 437 {
 438         void *p;
 439
 440         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 441                 efi_memory_desc_t *md = p;
 442                 unsigned long long start = md->phys_addr;
 443                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 444
 445                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 446                     md->type != EFI_BOOT_SERVICES_DATA)
 447                         continue;
 448
 449                 /* Could not reserve boot area */
 450                 if (!size)
 451                         continue;
 452
 453                 free_bootmem_late(start, size);
 454         }
 455 }
 456
 457 void __init efi_init(void)
 458 {
 459         efi_config_table_t *config_tables;
 460         efi_runtime_services_t *runtime;
 461         efi_char16_t *c16;
 462         char vendor[100] = "unknown";
 463         int i = 0;
 464         void *tmp;
 465
 466         if (!efi_is_native())
 467                 return;
 468
 469 #ifdef CONFIG_X86_32
 470         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 471 #else
 472         efi_phys.systab = (efi_system_table_t *)
 473                 (boot_params.efi_info.efi_systab |
 474                  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 475 #endif
 476
 477         efi.systab = early_ioremap((unsigned long)efi_phys.systab,
 478                                    sizeof(efi_system_table_t));
 479         if (efi.systab == NULL)
 480                 printk(KERN_ERR "Couldn't map the EFI system table!\n");
 481         memcpy(&efi_systab, efi.systab, sizeof(efi_system_table_t));
 482         early_iounmap(efi.systab, sizeof(efi_system_table_t));
 483         efi.systab = &efi_systab;
 484
 485         /*
 486          * Verify the EFI Table
 487          */
 488         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
 489                 printk(KERN_ERR "EFI system table signature incorrect!\n");
 490         if ((efi.systab->hdr.revision >> 16) == 0)
 491                 printk(KERN_ERR "Warning: EFI system table version "
 492                        "%d.%02d, expected 1.00 or greater!\n",
 493                        efi.systab->hdr.revision >> 16,
 494                        efi.systab->hdr.revision & 0xffff);
 495
 496         set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
 497
 498         /*
 499          * Show what we know for posterity
 500          */
 501         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 502         if (c16) {
 503                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 504                         vendor[i] = *c16++;
 505                 vendor[i] = '\0';
 506         } else
 507                 printk(KERN_ERR PFX "Could not map the firmware vendor!\n");
 508         early_iounmap(tmp, 2);
 509
 510         printk(KERN_INFO "EFI v%u.%.02u by %s\n",
 511                efi.systab->hdr.revision >> 16,
 512                efi.systab->hdr.revision & 0xffff, vendor);
 513
 514         /*
 515          * Let's see what config tables the firmware passed to us.
 516          */
 517         config_tables = early_ioremap(
 518                 efi.systab->tables,
 519                 efi.systab->nr_tables * sizeof(efi_config_table_t));
 520         if (config_tables == NULL)
 521                 printk(KERN_ERR "Could not map EFI Configuration Table!\n");
 522
 523         printk(KERN_INFO);
 524         for (i = 0; i < efi.systab->nr_tables; i++) {
 525                 if (!efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID)) {
 526                         efi.mps = config_tables[i].table;
 527                         printk(" MPS=0x%lx ", config_tables[i].table);
 528                 } else if (!efi_guidcmp(config_tables[i].guid,
 529                                         ACPI_20_TABLE_GUID)) {
 530                         efi.acpi20 = config_tables[i].table;
 531                         printk(" ACPI 2.0=0x%lx ", config_tables[i].table);
 532                 } else if (!efi_guidcmp(config_tables[i].guid,
 533                                         ACPI_TABLE_GUID)) {
 534                         efi.acpi = config_tables[i].table;
 535                         printk(" ACPI=0x%lx ", config_tables[i].table);
 536                 } else if (!efi_guidcmp(config_tables[i].guid,
 537                                         SMBIOS_TABLE_GUID)) {
 538                         efi.smbios = config_tables[i].table;
 539                         printk(" SMBIOS=0x%lx ", config_tables[i].table);
 540 #ifdef CONFIG_X86_UV
 541                 } else if (!efi_guidcmp(config_tables[i].guid,
 542                                         UV_SYSTEM_TABLE_GUID)) {
 543                         efi.uv_systab = config_tables[i].table;
 544                         printk(" UVsystab=0x%lx ", config_tables[i].table);
 545 #endif
 546                 } else if (!efi_guidcmp(config_tables[i].guid,
 547                                         HCDP_TABLE_GUID)) {
 548                         efi.hcdp = config_tables[i].table;
 549                         printk(" HCDP=0x%lx ", config_tables[i].table);
 550                 } else if (!efi_guidcmp(config_tables[i].guid,
 551                                         UGA_IO_PROTOCOL_GUID)) {
 552                         efi.uga = config_tables[i].table;
 553                         printk(" UGA=0x%lx ", config_tables[i].table);
 554                 }
 555         }
 556         printk("\n");
 557         early_iounmap(config_tables,
 558                           efi.systab->nr_tables * sizeof(efi_config_table_t));
 559
 560         set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
 561
 562         if (!disable_runtime) {
 563                 /*
 564                  * Check out the runtime services table. We need to map
 565                  * the runtime services table so that we can grab the physical
 566                  * address of several of the EFI runtime functions, needed to
 567                  * set the firmware into virtual mode.
 568                  */
 569                 runtime = early_ioremap((unsigned long)efi.systab->runtime,
 570                                         sizeof(efi_runtime_services_t));
 571                 if (runtime != NULL) {
 572                         /*
 573                          * We will only need *early* access to the following
 574                          * two EFI runtime services before set_virtual_address_map
 575                          * is invoked.
 576                          */
 577                         efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 578                         efi_phys.set_virtual_address_map =
 579                                 (efi_set_virtual_address_map_t *)
 580                                 runtime->set_virtual_address_map;
 581                         /*
 582                          * Make efi_get_time can be called before entering
 583                          * virtual mode.
 584                          */
 585                         efi.get_time = phys_efi_get_time;
 586
 587                         set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
 588                 } else
 589                         printk(KERN_ERR "Could not map the EFI runtime service "
 590                                "table!\n");
 591                 early_iounmap(runtime, sizeof(efi_runtime_services_t));
 592         }
 593
 594         /* Map the EFI memory map */
 595         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 596                                    memmap.nr_map * memmap.desc_size);
 597         if (memmap.map == NULL)
 598                 printk(KERN_ERR "Could not map the EFI memory map!\n");
 599         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 600
 601         if (memmap.desc_size != sizeof(efi_memory_desc_t))
 602                 printk(KERN_WARNING
 603                   "Kernel-defined memdesc doesn't match the one from EFI!\n");
 604
 605         if (add_efi_memmap)
 606                 do_add_efi_memmap();
 607
 608         set_bit(EFI_MEMMAP, &x86_efi_facility);
 609
 610 #ifdef CONFIG_X86_32
 611         x86_platform.get_wallclock = efi_get_time;
 612         x86_platform.set_wallclock = efi_set_rtc_mmss;
 613 #endif
 614
 615 #if EFI_DEBUG
 616         print_efi_memmap();
 617 #endif
 618 }
 619
 620 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 621 {
 622         u64 addr, npages;
 623
 624         addr = md->virt_addr;
 625         npages = md->num_pages;
 626
 627         memrange_efi_to_native(&addr, &npages);
 628
 629         if (executable)
 630                 set_memory_x(addr, npages);
 631         else
 632                 set_memory_nx(addr, npages);
 633 }
 634
 635 static void __init runtime_code_page_mkexec(void)
 636 {
 637         efi_memory_desc_t *md;
 638         void *p;
 639
 640         /* Make EFI runtime service code area executable */
 641         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 642                 md = p;
 643
 644                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 645                         continue;
 646
 647                 efi_set_executable(md, true);
 648         }
 649 }
 650
 651 /*
 652  * This function will switch the EFI runtime services to virtual mode.
 653  * Essentially, look through the EFI memmap and map every region that
 654  * has the runtime attribute bit set in its memory descriptor and update
 655  * that memory descriptor with the virtual address obtained from ioremap().
 656  * This enables the runtime services to be called without having to
 657  * thunk back into physical mode for every invocation.
 658  */
 659 void __init efi_enter_virtual_mode(void)
 660 {
 661         efi_memory_desc_t *md, *prev_md = NULL;
 662         efi_status_t status;
 663         unsigned long size;
 664         u64 end, systab, addr, npages, end_pfn;
 665         void *p, *va, *new_memmap = NULL;
 666         int count = 0;
 667
 668         efi.systab = NULL;
 669
 670         /* Merge contiguous regions of the same type and attribute */
 671         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 672                 u64 prev_size;
 673                 md = p;
 674
 675                 if (!prev_md) {
 676                         prev_md = md;
 677                         continue;
 678                 }
 679
 680                 if (prev_md->type != md->type ||
 681                     prev_md->attribute != md->attribute) {
 682                         prev_md = md;
 683                         continue;
 684                 }
 685
 686                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 687
 688                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 689                         prev_md->num_pages += md->num_pages;
 690                         md->type = EFI_RESERVED_TYPE;
 691                         md->attribute = 0;
 692                         continue;
 693                 }
 694                 prev_md = md;
 695         }
 696
 697         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 698                 md = p;
 699                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 700                     md->type != EFI_BOOT_SERVICES_CODE &&
 701                     md->type != EFI_BOOT_SERVICES_DATA)
 702                         continue;
 703
 704                 size = md->num_pages << EFI_PAGE_SHIFT;
 705                 end = md->phys_addr + size;
 706
 707                 end_pfn = PFN_UP(end);
 708                 if (end_pfn <= max_low_pfn_mapped
 709                     || (end_pfn > (1UL << (32 - PAGE_SHIFT))
 710                         && end_pfn <= max_pfn_mapped))
 711                         va = __va(md->phys_addr);
 712                 else
 713                         va = efi_ioremap(md->phys_addr, size, md->type);
 714
 715                 md->virt_addr = (u64) (unsigned long) va;
 716
 717                 if (!va) {
 718                         printk(KERN_ERR PFX "ioremap of 0x%llX failed!\n",
 719                                (unsigned long long)md->phys_addr);
 720                         continue;
 721                 }
 722
 723                 if (!(md->attribute & EFI_MEMORY_WB)) {
 724                         addr = md->virt_addr;
 725                         npages = md->num_pages;
 726                         memrange_efi_to_native(&addr, &npages);
 727                         set_memory_uc(addr, npages);
 728                 }
 729
 730                 systab = (u64) (unsigned long) efi_phys.systab;
 731                 if (md->phys_addr <= systab && systab < end) {
 732                         systab += md->virt_addr - md->phys_addr;
 733                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
 734                 }
 735                 new_memmap = krealloc(new_memmap,
 736                                       (count + 1) * memmap.desc_size,
 737                                       GFP_KERNEL);
 738                 memcpy(new_memmap + (count * memmap.desc_size), md,
 739                        memmap.desc_size);
 740                 count++;
 741         }
 742
 743         BUG_ON(!efi.systab);
 744
 745         status = phys_efi_set_virtual_address_map(
 746                 memmap.desc_size * count,
 747                 memmap.desc_size,
 748                 memmap.desc_version,
 749                 (efi_memory_desc_t *)__pa(new_memmap));
 750
 751         if (status != EFI_SUCCESS) {
 752                 printk(KERN_ALERT "Unable to switch EFI into virtual mode "
 753                        "(status=%lx)!\n", status);
 754                 panic("EFI call to SetVirtualAddressMap() failed!");
 755         }
 756
 757         /*
 758          * Thankfully, it does seem that no runtime services other than
 759          * SetVirtualAddressMap() will touch boot services code, so we can
 760          * get rid of it all at this point
 761          */
 762         efi_free_boot_services();
 763
 764         /*
 765          * Now that EFI is in virtual mode, update the function
 766          * pointers in the runtime service table to the new virtual addresses.
 767          *
 768          * Call EFI services through wrapper functions.
 769          */
 770         efi.runtime_version = efi_systab.hdr.revision;
 771         efi.get_time = virt_efi_get_time;
 772         efi.set_time = virt_efi_set_time;
 773         efi.get_wakeup_time = virt_efi_get_wakeup_time;
 774         efi.set_wakeup_time = virt_efi_set_wakeup_time;
 775         efi.get_variable = virt_efi_get_variable;
 776         efi.get_next_variable = virt_efi_get_next_variable;
 777         efi.set_variable = virt_efi_set_variable;
 778         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
 779         efi.reset_system = virt_efi_reset_system;
 780         efi.set_virtual_address_map = NULL;
 781         efi.query_variable_info = virt_efi_query_variable_info;
 782         efi.update_capsule = virt_efi_update_capsule;
 783         efi.query_capsule_caps = virt_efi_query_capsule_caps;
 784         if (__supported_pte_mask & _PAGE_NX)
 785                 runtime_code_page_mkexec();
 786         clear_bit(EFI_MEMMAP, &x86_efi_facility);
 787         early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 788         memmap.map = NULL;
 789         kfree(new_memmap);
 790 }
 791
 792 /*
 793  * Convenience functions to obtain memory types and attributes
 794  */
 795 u32 efi_mem_type(unsigned long phys_addr)
 796 {
 797         efi_memory_desc_t *md;
 798         void *p;
 799
 800         if (!efi_enabled(EFI_MEMMAP))
 801                 return 0;
 802
 803         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 804                 md = p;
 805                 if ((md->phys_addr <= phys_addr) &&
 806                     (phys_addr < (md->phys_addr +
 807                                   (md->num_pages << EFI_PAGE_SHIFT))))
 808                         return md->type;
 809         }
 810         return 0;
 811 }
 812
 813 u64 efi_mem_attributes(unsigned long phys_addr)
 814 {
 815         efi_memory_desc_t *md;
 816         void *p;
 817
 818         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 819                 md = p;
 820                 if ((md->phys_addr <= phys_addr) &&
 821                     (phys_addr < (md->phys_addr +
 822                                   (md->num_pages << EFI_PAGE_SHIFT))))
 823                         return md->attribute;
 824         }
 825         return 0;
 826 }
 827
 828 /*
 829  * Some firmware has serious problems when using more than 50% of the EFI
 830  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
 831  * we never use more than this safe limit.
 832  *
 833  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
 834  * store.
 835  */
 836 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
 837 {
 838         efi_status_t status;
 839         u64 storage_size, remaining_size, max_size;
 840
 841         status = efi.query_variable_info(attributes, &storage_size,
 842                                          &remaining_size, &max_size);
 843         if (status != EFI_SUCCESS)
 844                 return status;
 845
 846         if (!max_size && remaining_size > size)
 847                 printk_once(KERN_ERR FW_BUG "Broken EFI implementation"
 848                             " is returning MaxVariableSize=0\n");
 849
 850         if (!storage_size || size > remaining_size ||
 851             (max_size && size > max_size))
 852                 return EFI_OUT_OF_RESOURCES;
 853
 854         if (!efi_no_storage_paranoia &&
 855             (remaining_size - size) < (storage_size / 2))
 856                 return EFI_OUT_OF_RESOURCES;
 857
 858         return EFI_SUCCESS;
 859 }
 860 EXPORT_SYMBOL_GPL(efi_query_variable_store);