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/bootmem.h>
  33 #include <linux/memblock.h>
  34 #include <linux/spinlock.h>
  35 #include <linux/uaccess.h>
  36 #include <linux/time.h>
  37 #include <linux/io.h>
  38 #include <linux/reboot.h>
  39 #include <linux/bcd.h>
  40
  41 #include <asm/setup.h>
  42 #include <asm/efi.h>
  43 #include <asm/time.h>
  44 #include <asm/cacheflush.h>
  45 #include <asm/tlbflush.h>
  46 #include <asm/x86_init.h>
  47
  48 #define EFI_DEBUG       1
  49 #define PFX             "EFI: "
  50
  51 int efi_enabled;
  52 EXPORT_SYMBOL(efi_enabled);
  53
  54 struct efi efi;
  55 EXPORT_SYMBOL(efi);
  56
  57 struct efi_memory_map memmap;
  58
  59 static struct efi efi_phys __initdata;
  60 static efi_system_table_t efi_systab __initdata;
  61
  62 static int __init setup_noefi(char *arg)
  63 {
  64         efi_enabled = 0;
  65         return 0;
  66 }
  67 early_param("noefi", setup_noefi);
  68
  69 int add_efi_memmap;
  70 EXPORT_SYMBOL(add_efi_memmap);
  71
  72 static int __init setup_add_efi_memmap(char *arg)
  73 {
  74         add_efi_memmap = 1;
  75         return 0;
  76 }
  77 early_param("add_efi_memmap", setup_add_efi_memmap);
  78
  79
  80 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
  81 {
  82         return efi_call_virt2(get_time, tm, tc);
  83 }
  84
  85 static efi_status_t virt_efi_set_time(efi_time_t *tm)
  86 {
  87         return efi_call_virt1(set_time, tm);
  88 }
  89
  90 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
  91                                              efi_bool_t *pending,
  92                                              efi_time_t *tm)
  93 {
  94         return efi_call_virt3(get_wakeup_time,
  95                               enabled, pending, tm);
  96 }
  97
  98 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
  99 {
 100         return efi_call_virt2(set_wakeup_time,
 101                               enabled, tm);
 102 }
 103
 104 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
 105                                           efi_guid_t *vendor,
 106                                           u32 *attr,
 107                                           unsigned long *data_size,
 108                                           void *data)
 109 {
 110         return efi_call_virt5(get_variable,
 111                               name, vendor, attr,
 112                               data_size, data);
 113 }
 114
 115 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 116                                                efi_char16_t *name,
 117                                                efi_guid_t *vendor)
 118 {
 119         return efi_call_virt3(get_next_variable,
 120                               name_size, name, vendor);
 121 }
 122
 123 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 124                                           efi_guid_t *vendor,
 125                                           unsigned long attr,
 126                                           unsigned long data_size,
 127                                           void *data)
 128 {
 129         return efi_call_virt5(set_variable,
 130                               name, vendor, attr,
 131                               data_size, data);
 132 }
 133
 134 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 135 {
 136         return efi_call_virt1(get_next_high_mono_count, count);
 137 }
 138
 139 static void virt_efi_reset_system(int reset_type,
 140                                   efi_status_t status,
 141                                   unsigned long data_size,
 142                                   efi_char16_t *data)
 143 {
 144         efi_call_virt4(reset_system, reset_type, status,
 145                        data_size, data);
 146 }
 147
 148 static efi_status_t __init phys_efi_set_virtual_address_map(
 149         unsigned long memory_map_size,
 150         unsigned long descriptor_size,
 151         u32 descriptor_version,
 152         efi_memory_desc_t *virtual_map)
 153 {
 154         efi_status_t status;
 155
 156         efi_call_phys_prelog();
 157         status = efi_call_phys4(efi_phys.set_virtual_address_map,
 158                                 memory_map_size, descriptor_size,
 159                                 descriptor_version, virtual_map);
 160         efi_call_phys_epilog();
 161         return status;
 162 }
 163
 164 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
 165                                              efi_time_cap_t *tc)
 166 {
 167         efi_status_t status;
 168
 169         efi_call_phys_prelog();
 170         status = efi_call_phys2(efi_phys.get_time, tm, tc);
 171         efi_call_phys_epilog();
 172         return status;
 173 }
 174
 175 int efi_set_rtc_mmss(unsigned long nowtime)
 176 {
 177         int real_seconds, real_minutes;
 178         efi_status_t    status;
 179         efi_time_t      eft;
 180         efi_time_cap_t  cap;
 181
 182         status = efi.get_time(&eft, &cap);
 183         if (status != EFI_SUCCESS) {
 184                 printk(KERN_ERR "Oops: efitime: can't read time!\n");
 185                 return -1;
 186         }
 187
 188         real_seconds = nowtime % 60;
 189         real_minutes = nowtime / 60;
 190         if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
 191                 real_minutes += 30;
 192         real_minutes %= 60;
 193         eft.minute = real_minutes;
 194         eft.second = real_seconds;
 195
 196         status = efi.set_time(&eft);
 197         if (status != EFI_SUCCESS) {
 198                 printk(KERN_ERR "Oops: efitime: can't write time!\n");
 199                 return -1;
 200         }
 201         return 0;
 202 }
 203
 204 unsigned long efi_get_time(void)
 205 {
 206         efi_status_t status;
 207         efi_time_t eft;
 208         efi_time_cap_t cap;
 209
 210         status = efi.get_time(&eft, &cap);
 211         if (status != EFI_SUCCESS)
 212                 printk(KERN_ERR "Oops: efitime: can't read time!\n");
 213
 214         return mktime(eft.year, eft.month, eft.day, eft.hour,
 215                       eft.minute, eft.second);
 216 }
 217
 218 /*
 219  * Tell the kernel about the EFI memory map.  This might include
 220  * more than the max 128 entries that can fit in the e820 legacy
 221  * (zeropage) memory map.
 222  */
 223
 224 static void __init do_add_efi_memmap(void)
 225 {
 226         void *p;
 227
 228         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 229                 efi_memory_desc_t *md = p;
 230                 unsigned long long start = md->phys_addr;
 231                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 232                 int e820_type;
 233
 234                 switch (md->type) {
 235                 case EFI_LOADER_CODE:
 236                 case EFI_LOADER_DATA:
 237                 case EFI_BOOT_SERVICES_CODE:
 238                 case EFI_BOOT_SERVICES_DATA:
 239                 case EFI_CONVENTIONAL_MEMORY:
 240                         if (md->attribute & EFI_MEMORY_WB)
 241                                 e820_type = E820_RAM;
 242                         else
 243                                 e820_type = E820_RESERVED;
 244                         break;
 245                 case EFI_ACPI_RECLAIM_MEMORY:
 246                         e820_type = E820_ACPI;
 247                         break;
 248                 case EFI_ACPI_MEMORY_NVS:
 249                         e820_type = E820_NVS;
 250                         break;
 251                 case EFI_UNUSABLE_MEMORY:
 252                         e820_type = E820_UNUSABLE;
 253                         break;
 254                 default:
 255                         /*
 256                          * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 257                          * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 258                          * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 259                          */
 260                         e820_type = E820_RESERVED;
 261                         break;
 262                 }
 263                 e820_add_region(start, size, e820_type);
 264         }
 265         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 266 }
 267
 268 void __init efi_memblock_x86_reserve_range(void)
 269 {
 270         unsigned long pmap;
 271
 272 #ifdef CONFIG_X86_32
 273         pmap = boot_params.efi_info.efi_memmap;
 274 #else
 275         pmap = (boot_params.efi_info.efi_memmap |
 276                 ((__u64)boot_params.efi_info.efi_memmap_hi<<32));
 277 #endif
 278         memmap.phys_map = (void *)pmap;
 279         memmap.nr_map = boot_params.efi_info.efi_memmap_size /
 280                 boot_params.efi_info.efi_memdesc_size;
 281         memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
 282         memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
 283         memblock_x86_reserve_range(pmap, pmap + memmap.nr_map * memmap.desc_size,
 284                       "EFI memmap");
 285 }
 286
 287 #if EFI_DEBUG
 288 static void __init print_efi_memmap(void)
 289 {
 290         efi_memory_desc_t *md;
 291         void *p;
 292         int i;
 293
 294         for (p = memmap.map, i = 0;
 295              p < memmap.map_end;
 296              p += memmap.desc_size, i++) {
 297                 md = p;
 298                 printk(KERN_INFO PFX "mem%02u: type=%u, attr=0x%llx, "
 299                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 300                         i, md->type, md->attribute, md->phys_addr,
 301                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 302                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 303         }
 304 }
 305 #endif  /*  EFI_DEBUG  */
 306
 307 void __init efi_reserve_boot_services(void)
 308 {
 309         void *p;
 310
 311         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 312                 efi_memory_desc_t *md = p;
 313                 u64 start = md->phys_addr;
 314                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 315
 316                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 317                     md->type != EFI_BOOT_SERVICES_DATA)
 318                         continue;
 319                 /* Only reserve where possible:
 320                  * - Not within any already allocated areas
 321                  * - Not over any memory area (really needed, if above?)
 322                  * - Not within any part of the kernel
 323                  * - Not the bios reserved area
 324                 */
 325                 if ((start+size >= virt_to_phys(_text)
 326                                 && start <= virt_to_phys(_end)) ||
 327                         !e820_all_mapped(start, start+size, E820_RAM) ||
 328                         memblock_x86_check_reserved_size(&start, &size,
 329                                                         1<<EFI_PAGE_SHIFT)) {
 330                         /* Could not reserve, skip it */
 331                         md->num_pages = 0;
 332                         memblock_dbg(PFX "Could not reserve boot range "
 333                                         "[0x%010llx-0x%010llx]\n",
 334                                                 start, start+size-1);
 335                 } else
 336                         memblock_x86_reserve_range(start, start+size,
 337                                                         "EFI Boot");
 338         }
 339 }
 340
 341 static void __init efi_free_boot_services(void)
 342 {
 343         void *p;
 344
 345         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 346                 efi_memory_desc_t *md = p;
 347                 unsigned long long start = md->phys_addr;
 348                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 349
 350                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 351                     md->type != EFI_BOOT_SERVICES_DATA)
 352                         continue;
 353
 354                 /* Could not reserve boot area */
 355                 if (!size)
 356                         continue;
 357
 358                 free_bootmem_late(start, size);
 359         }
 360 }
 361
 362 void __init efi_init(void)
 363 {
 364         efi_config_table_t *config_tables;
 365         efi_runtime_services_t *runtime;
 366         efi_char16_t *c16;
 367         char vendor[100] = "unknown";
 368         int i = 0;
 369         void *tmp;
 370
 371 #ifdef CONFIG_X86_32
 372         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 373 #else
 374         efi_phys.systab = (efi_system_table_t *)
 375                 (boot_params.efi_info.efi_systab |
 376                  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 377 #endif
 378
 379         efi.systab = early_ioremap((unsigned long)efi_phys.systab,
 380                                    sizeof(efi_system_table_t));
 381         if (efi.systab == NULL)
 382                 printk(KERN_ERR "Couldn't map the EFI system table!\n");
 383         memcpy(&efi_systab, efi.systab, sizeof(efi_system_table_t));
 384         early_iounmap(efi.systab, sizeof(efi_system_table_t));
 385         efi.systab = &efi_systab;
 386
 387         /*
 388          * Verify the EFI Table
 389          */
 390         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
 391                 printk(KERN_ERR "EFI system table signature incorrect!\n");
 392         if ((efi.systab->hdr.revision >> 16) == 0)
 393                 printk(KERN_ERR "Warning: EFI system table version "
 394                        "%d.%02d, expected 1.00 or greater!\n",
 395                        efi.systab->hdr.revision >> 16,
 396                        efi.systab->hdr.revision & 0xffff);
 397
 398         /*
 399          * Show what we know for posterity
 400          */
 401         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 402         if (c16) {
 403                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 404                         vendor[i] = *c16++;
 405                 vendor[i] = '\0';
 406         } else
 407                 printk(KERN_ERR PFX "Could not map the firmware vendor!\n");
 408         early_iounmap(tmp, 2);
 409
 410         printk(KERN_INFO "EFI v%u.%.02u by %s\n",
 411                efi.systab->hdr.revision >> 16,
 412                efi.systab->hdr.revision & 0xffff, vendor);
 413
 414         /*
 415          * Let's see what config tables the firmware passed to us.
 416          */
 417         config_tables = early_ioremap(
 418                 efi.systab->tables,
 419                 efi.systab->nr_tables * sizeof(efi_config_table_t));
 420         if (config_tables == NULL)
 421                 printk(KERN_ERR "Could not map EFI Configuration Table!\n");
 422
 423         printk(KERN_INFO);
 424         for (i = 0; i < efi.systab->nr_tables; i++) {
 425                 if (!efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID)) {
 426                         efi.mps = config_tables[i].table;
 427                         printk(" MPS=0x%lx ", config_tables[i].table);
 428                 } else if (!efi_guidcmp(config_tables[i].guid,
 429                                         ACPI_20_TABLE_GUID)) {
 430                         efi.acpi20 = config_tables[i].table;
 431                         printk(" ACPI 2.0=0x%lx ", config_tables[i].table);
 432                 } else if (!efi_guidcmp(config_tables[i].guid,
 433                                         ACPI_TABLE_GUID)) {
 434                         efi.acpi = config_tables[i].table;
 435                         printk(" ACPI=0x%lx ", config_tables[i].table);
 436                 } else if (!efi_guidcmp(config_tables[i].guid,
 437                                         SMBIOS_TABLE_GUID)) {
 438                         efi.smbios = config_tables[i].table;
 439                         printk(" SMBIOS=0x%lx ", config_tables[i].table);
 440 #ifdef CONFIG_X86_UV
 441                 } else if (!efi_guidcmp(config_tables[i].guid,
 442                                         UV_SYSTEM_TABLE_GUID)) {
 443                         efi.uv_systab = config_tables[i].table;
 444                         printk(" UVsystab=0x%lx ", config_tables[i].table);
 445 #endif
 446                 } else if (!efi_guidcmp(config_tables[i].guid,
 447                                         HCDP_TABLE_GUID)) {
 448                         efi.hcdp = config_tables[i].table;
 449                         printk(" HCDP=0x%lx ", config_tables[i].table);
 450                 } else if (!efi_guidcmp(config_tables[i].guid,
 451                                         UGA_IO_PROTOCOL_GUID)) {
 452                         efi.uga = config_tables[i].table;
 453                         printk(" UGA=0x%lx ", config_tables[i].table);
 454                 }
 455         }
 456         printk("\n");
 457         early_iounmap(config_tables,
 458                           efi.systab->nr_tables * sizeof(efi_config_table_t));
 459
 460         /*
 461          * Check out the runtime services table. We need to map
 462          * the runtime services table so that we can grab the physical
 463          * address of several of the EFI runtime functions, needed to
 464          * set the firmware into virtual mode.
 465          */
 466         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 467                                 sizeof(efi_runtime_services_t));
 468         if (runtime != NULL) {
 469                 /*
 470                  * We will only need *early* access to the following
 471                  * two EFI runtime services before set_virtual_address_map
 472                  * is invoked.
 473                  */
 474                 efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 475                 efi_phys.set_virtual_address_map =
 476                         (efi_set_virtual_address_map_t *)
 477                         runtime->set_virtual_address_map;
 478                 /*
 479                  * Make efi_get_time can be called before entering
 480                  * virtual mode.
 481                  */
 482                 efi.get_time = phys_efi_get_time;
 483         } else
 484                 printk(KERN_ERR "Could not map the EFI runtime service "
 485                        "table!\n");
 486         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 487
 488         /* Map the EFI memory map */
 489         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 490                                    memmap.nr_map * memmap.desc_size);
 491         if (memmap.map == NULL)
 492                 printk(KERN_ERR "Could not map the EFI memory map!\n");
 493         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 494
 495         if (memmap.desc_size != sizeof(efi_memory_desc_t))
 496                 printk(KERN_WARNING
 497                   "Kernel-defined memdesc doesn't match the one from EFI!\n");
 498
 499         if (add_efi_memmap)
 500                 do_add_efi_memmap();
 501
 502 #ifdef CONFIG_X86_32
 503         x86_platform.get_wallclock = efi_get_time;
 504         x86_platform.set_wallclock = efi_set_rtc_mmss;
 505 #endif
 506
 507         /* Setup for EFI runtime service */
 508         reboot_type = BOOT_EFI;
 509
 510 #if EFI_DEBUG
 511         print_efi_memmap();
 512 #endif
 513 }
 514
 515 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 516 {
 517         u64 addr, npages;
 518
 519         addr = md->virt_addr;
 520         npages = md->num_pages;
 521
 522         memrange_efi_to_native(&addr, &npages);
 523
 524         if (executable)
 525                 set_memory_x(addr, npages);
 526         else
 527                 set_memory_nx(addr, npages);
 528 }
 529
 530 static void __init runtime_code_page_mkexec(void)
 531 {
 532         efi_memory_desc_t *md;
 533         void *p;
 534
 535         /* Make EFI runtime service code area executable */
 536         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 537                 md = p;
 538
 539                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 540                         continue;
 541
 542                 efi_set_executable(md, true);
 543         }
 544 }
 545
 546 /*
 547  * This function will switch the EFI runtime services to virtual mode.
 548  * Essentially, look through the EFI memmap and map every region that
 549  * has the runtime attribute bit set in its memory descriptor and update
 550  * that memory descriptor with the virtual address obtained from ioremap().
 551  * This enables the runtime services to be called without having to
 552  * thunk back into physical mode for every invocation.
 553  */
 554 void __init efi_enter_virtual_mode(void)
 555 {
 556         efi_memory_desc_t *md, *prev_md = NULL;
 557         efi_status_t status;
 558         unsigned long size;
 559         u64 end, systab, addr, npages, end_pfn;
 560         void *p, *va, *new_memmap = NULL;
 561         int count = 0;
 562
 563         efi.systab = NULL;
 564
 565         /* Merge contiguous regions of the same type and attribute */
 566         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 567                 u64 prev_size;
 568                 md = p;
 569
 570                 if (!prev_md) {
 571                         prev_md = md;
 572                         continue;
 573                 }
 574
 575                 if (prev_md->type != md->type ||
 576                     prev_md->attribute != md->attribute) {
 577                         prev_md = md;
 578                         continue;
 579                 }
 580
 581                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 582
 583                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 584                         prev_md->num_pages += md->num_pages;
 585                         md->type = EFI_RESERVED_TYPE;
 586                         md->attribute = 0;
 587                         continue;
 588                 }
 589                 prev_md = md;
 590         }
 591
 592         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 593                 md = p;
 594                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 595                     md->type != EFI_BOOT_SERVICES_CODE &&
 596                     md->type != EFI_BOOT_SERVICES_DATA)
 597                         continue;
 598
 599                 size = md->num_pages << EFI_PAGE_SHIFT;
 600                 end = md->phys_addr + size;
 601
 602                 end_pfn = PFN_UP(end);
 603                 if (end_pfn <= max_low_pfn_mapped
 604                     || (end_pfn > (1UL << (32 - PAGE_SHIFT))
 605                         && end_pfn <= max_pfn_mapped))
 606                         va = __va(md->phys_addr);
 607                 else
 608                         va = efi_ioremap(md->phys_addr, size, md->type);
 609
 610                 md->virt_addr = (u64) (unsigned long) va;
 611
 612                 if (!va) {
 613                         printk(KERN_ERR PFX "ioremap of 0x%llX failed!\n",
 614                                (unsigned long long)md->phys_addr);
 615                         continue;
 616                 }
 617
 618                 if (!(md->attribute & EFI_MEMORY_WB)) {
 619                         addr = md->virt_addr;
 620                         npages = md->num_pages;
 621                         memrange_efi_to_native(&addr, &npages);
 622                         set_memory_uc(addr, npages);
 623                 }
 624
 625                 systab = (u64) (unsigned long) efi_phys.systab;
 626                 if (md->phys_addr <= systab && systab < end) {
 627                         systab += md->virt_addr - md->phys_addr;
 628                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
 629                 }
 630                 new_memmap = krealloc(new_memmap,
 631                                       (count + 1) * memmap.desc_size,
 632                                       GFP_KERNEL);
 633                 memcpy(new_memmap + (count * memmap.desc_size), md,
 634                        memmap.desc_size);
 635                 count++;
 636         }
 637
 638         BUG_ON(!efi.systab);
 639
 640         status = phys_efi_set_virtual_address_map(
 641                 memmap.desc_size * count,
 642                 memmap.desc_size,
 643                 memmap.desc_version,
 644                 (efi_memory_desc_t *)__pa(new_memmap));
 645
 646         if (status != EFI_SUCCESS) {
 647                 printk(KERN_ALERT "Unable to switch EFI into virtual mode "
 648                        "(status=%lx)!\n", status);
 649                 panic("EFI call to SetVirtualAddressMap() failed!");
 650         }
 651
 652         /*
 653          * Thankfully, it does seem that no runtime services other than
 654          * SetVirtualAddressMap() will touch boot services code, so we can
 655          * get rid of it all at this point
 656          */
 657         efi_free_boot_services();
 658
 659         /*
 660          * Now that EFI is in virtual mode, update the function
 661          * pointers in the runtime service table to the new virtual addresses.
 662          *
 663          * Call EFI services through wrapper functions.
 664          */
 665         efi.get_time = virt_efi_get_time;
 666         efi.set_time = virt_efi_set_time;
 667         efi.get_wakeup_time = virt_efi_get_wakeup_time;
 668         efi.set_wakeup_time = virt_efi_set_wakeup_time;
 669         efi.get_variable = virt_efi_get_variable;
 670         efi.get_next_variable = virt_efi_get_next_variable;
 671         efi.set_variable = virt_efi_set_variable;
 672         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
 673         efi.reset_system = virt_efi_reset_system;
 674         efi.set_virtual_address_map = NULL;
 675         if (__supported_pte_mask & _PAGE_NX)
 676                 runtime_code_page_mkexec();
 677         early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 678         memmap.map = NULL;
 679         kfree(new_memmap);
 680 }
 681
 682 /*
 683  * Convenience functions to obtain memory types and attributes
 684  */
 685 u32 efi_mem_type(unsigned long phys_addr)
 686 {
 687         efi_memory_desc_t *md;
 688         void *p;
 689
 690         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 691                 md = p;
 692                 if ((md->phys_addr <= phys_addr) &&
 693                     (phys_addr < (md->phys_addr +
 694                                   (md->num_pages << EFI_PAGE_SHIFT))))
 695                         return md->type;
 696         }
 697         return 0;
 698 }
 699
 700 u64 efi_mem_attributes(unsigned long phys_addr)
 701 {
 702         efi_memory_desc_t *md;
 703         void *p;
 704
 705         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 706                 md = p;
 707                 if ((md->phys_addr <= phys_addr) &&
 708                     (phys_addr < (md->phys_addr +
 709                                   (md->num_pages << EFI_PAGE_SHIFT))))
 710                         return md->attribute;
 711         }
 712         return 0;
 713 }