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 unsigned long x86_efi_facility;
  69
  70 static __initdata efi_config_table_type_t arch_tables[] = {
  71 #ifdef CONFIG_X86_UV
  72         {UV_SYSTEM_TABLE_GUID, "UVsystab", &efi.uv_systab},
  73 #endif
  74         {NULL_GUID, NULL, NULL},
  75 };
  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 __initdata 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, virt_to_phys(tm),
 265                                 virt_to_phys(tc));
 266         efi_call_phys_epilog();
 267         spin_unlock_irqrestore(&rtc_lock, flags);
 268         return status;
 269 }
 270
 271 int efi_set_rtc_mmss(const struct timespec *now)
 272 {
 273         unsigned long nowtime = now->tv_sec;
 274         efi_status_t    status;
 275         efi_time_t      eft;
 276         efi_time_cap_t  cap;
 277         struct rtc_time tm;
 278
 279         status = efi.get_time(&eft, &cap);
 280         if (status != EFI_SUCCESS) {
 281                 pr_err("Oops: efitime: can't read time!\n");
 282                 return -1;
 283         }
 284
 285         rtc_time_to_tm(nowtime, &tm);
 286         if (!rtc_valid_tm(&tm)) {
 287                 eft.year = tm.tm_year + 1900;
 288                 eft.month = tm.tm_mon + 1;
 289                 eft.day = tm.tm_mday;
 290                 eft.minute = tm.tm_min;
 291                 eft.second = tm.tm_sec;
 292                 eft.nanosecond = 0;
 293         } else {
 294                 printk(KERN_ERR
 295                        "%s: Invalid EFI RTC value: write of %lx to EFI RTC failed\n",
 296                        __FUNCTION__, nowtime);
 297                 return -1;
 298         }
 299
 300         status = efi.set_time(&eft);
 301         if (status != EFI_SUCCESS) {
 302                 pr_err("Oops: efitime: can't write time!\n");
 303                 return -1;
 304         }
 305         return 0;
 306 }
 307
 308 void efi_get_time(struct timespec *now)
 309 {
 310         efi_status_t status;
 311         efi_time_t eft;
 312         efi_time_cap_t cap;
 313
 314         status = efi.get_time(&eft, &cap);
 315         if (status != EFI_SUCCESS)
 316                 pr_err("Oops: efitime: can't read time!\n");
 317
 318         now->tv_sec = mktime(eft.year, eft.month, eft.day, eft.hour,
 319                              eft.minute, eft.second);
 320         now->tv_nsec = 0;
 321 }
 322
 323 /*
 324  * Tell the kernel about the EFI memory map.  This might include
 325  * more than the max 128 entries that can fit in the e820 legacy
 326  * (zeropage) memory map.
 327  */
 328
 329 static void __init do_add_efi_memmap(void)
 330 {
 331         void *p;
 332
 333         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 334                 efi_memory_desc_t *md = p;
 335                 unsigned long long start = md->phys_addr;
 336                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 337                 int e820_type;
 338
 339                 switch (md->type) {
 340                 case EFI_LOADER_CODE:
 341                 case EFI_LOADER_DATA:
 342                 case EFI_BOOT_SERVICES_CODE:
 343                 case EFI_BOOT_SERVICES_DATA:
 344                 case EFI_CONVENTIONAL_MEMORY:
 345                         if (md->attribute & EFI_MEMORY_WB)
 346                                 e820_type = E820_RAM;
 347                         else
 348                                 e820_type = E820_RESERVED;
 349                         break;
 350                 case EFI_ACPI_RECLAIM_MEMORY:
 351                         e820_type = E820_ACPI;
 352                         break;
 353                 case EFI_ACPI_MEMORY_NVS:
 354                         e820_type = E820_NVS;
 355                         break;
 356                 case EFI_UNUSABLE_MEMORY:
 357                         e820_type = E820_UNUSABLE;
 358                         break;
 359                 default:
 360                         /*
 361                          * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 362                          * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 363                          * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 364                          */
 365                         e820_type = E820_RESERVED;
 366                         break;
 367                 }
 368                 e820_add_region(start, size, e820_type);
 369         }
 370         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 371 }
 372
 373 int __init efi_memblock_x86_reserve_range(void)
 374 {
 375         struct efi_info *e = &boot_params.efi_info;
 376         unsigned long pmap;
 377
 378 #ifdef CONFIG_X86_32
 379         /* Can't handle data above 4GB at this time */
 380         if (e->efi_memmap_hi) {
 381                 pr_err("Memory map is above 4GB, disabling EFI.\n");
 382                 return -EINVAL;
 383         }
 384         pmap =  e->efi_memmap;
 385 #else
 386         pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
 387 #endif
 388         memmap.phys_map         = (void *)pmap;
 389         memmap.nr_map           = e->efi_memmap_size /
 390                                   e->efi_memdesc_size;
 391         memmap.desc_size        = e->efi_memdesc_size;
 392         memmap.desc_version     = e->efi_memdesc_version;
 393
 394         memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 395
 396         efi.memmap = &memmap;
 397
 398         return 0;
 399 }
 400
 401 #if EFI_DEBUG
 402 static void __init print_efi_memmap(void)
 403 {
 404         efi_memory_desc_t *md;
 405         void *p;
 406         int i;
 407
 408         for (p = memmap.map, i = 0;
 409              p < memmap.map_end;
 410              p += memmap.desc_size, i++) {
 411                 md = p;
 412                 pr_info("mem%02u: type=%u, attr=0x%llx, "
 413                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 414                         i, md->type, md->attribute, md->phys_addr,
 415                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 416                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 417         }
 418 }
 419 #endif  /*  EFI_DEBUG  */
 420
 421 void __init efi_reserve_boot_services(void)
 422 {
 423         void *p;
 424
 425         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 426                 efi_memory_desc_t *md = p;
 427                 u64 start = md->phys_addr;
 428                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 429
 430                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 431                     md->type != EFI_BOOT_SERVICES_DATA)
 432                         continue;
 433                 /* Only reserve where possible:
 434                  * - Not within any already allocated areas
 435                  * - Not over any memory area (really needed, if above?)
 436                  * - Not within any part of the kernel
 437                  * - Not the bios reserved area
 438                 */
 439                 if ((start+size >= __pa_symbol(_text)
 440                                 && start <= __pa_symbol(_end)) ||
 441                         !e820_all_mapped(start, start+size, E820_RAM) ||
 442                         memblock_is_region_reserved(start, size)) {
 443                         /* Could not reserve, skip it */
 444                         md->num_pages = 0;
 445                         memblock_dbg("Could not reserve boot range "
 446                                         "[0x%010llx-0x%010llx]\n",
 447                                                 start, start+size-1);
 448                 } else
 449                         memblock_reserve(start, size);
 450         }
 451 }
 452
 453 void __init efi_unmap_memmap(void)
 454 {
 455         clear_bit(EFI_MEMMAP, &x86_efi_facility);
 456         if (memmap.map) {
 457                 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 458                 memmap.map = NULL;
 459         }
 460 }
 461
 462 void __init efi_free_boot_services(void)
 463 {
 464         void *p;
 465
 466         if (!efi_is_native())
 467                 return;
 468
 469         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 470                 efi_memory_desc_t *md = p;
 471                 unsigned long long start = md->phys_addr;
 472                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 473
 474                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 475                     md->type != EFI_BOOT_SERVICES_DATA)
 476                         continue;
 477
 478                 /* Could not reserve boot area */
 479                 if (!size)
 480                         continue;
 481
 482                 free_bootmem_late(start, size);
 483         }
 484
 485         efi_unmap_memmap();
 486 }
 487
 488 static int __init efi_systab_init(void *phys)
 489 {
 490         if (efi_enabled(EFI_64BIT)) {
 491                 efi_system_table_64_t *systab64;
 492                 u64 tmp = 0;
 493
 494                 systab64 = early_ioremap((unsigned long)phys,
 495                                          sizeof(*systab64));
 496                 if (systab64 == NULL) {
 497                         pr_err("Couldn't map the system table!\n");
 498                         return -ENOMEM;
 499                 }
 500
 501                 efi_systab.hdr = systab64->hdr;
 502                 efi_systab.fw_vendor = systab64->fw_vendor;
 503                 tmp |= systab64->fw_vendor;
 504                 efi_systab.fw_revision = systab64->fw_revision;
 505                 efi_systab.con_in_handle = systab64->con_in_handle;
 506                 tmp |= systab64->con_in_handle;
 507                 efi_systab.con_in = systab64->con_in;
 508                 tmp |= systab64->con_in;
 509                 efi_systab.con_out_handle = systab64->con_out_handle;
 510                 tmp |= systab64->con_out_handle;
 511                 efi_systab.con_out = systab64->con_out;
 512                 tmp |= systab64->con_out;
 513                 efi_systab.stderr_handle = systab64->stderr_handle;
 514                 tmp |= systab64->stderr_handle;
 515                 efi_systab.stderr = systab64->stderr;
 516                 tmp |= systab64->stderr;
 517                 efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
 518                 tmp |= systab64->runtime;
 519                 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
 520                 tmp |= systab64->boottime;
 521                 efi_systab.nr_tables = systab64->nr_tables;
 522                 efi_systab.tables = systab64->tables;
 523                 tmp |= systab64->tables;
 524
 525                 early_iounmap(systab64, sizeof(*systab64));
 526 #ifdef CONFIG_X86_32
 527                 if (tmp >> 32) {
 528                         pr_err("EFI data located above 4GB, disabling EFI.\n");
 529                         return -EINVAL;
 530                 }
 531 #endif
 532         } else {
 533                 efi_system_table_32_t *systab32;
 534
 535                 systab32 = early_ioremap((unsigned long)phys,
 536                                          sizeof(*systab32));
 537                 if (systab32 == NULL) {
 538                         pr_err("Couldn't map the system table!\n");
 539                         return -ENOMEM;
 540                 }
 541
 542                 efi_systab.hdr = systab32->hdr;
 543                 efi_systab.fw_vendor = systab32->fw_vendor;
 544                 efi_systab.fw_revision = systab32->fw_revision;
 545                 efi_systab.con_in_handle = systab32->con_in_handle;
 546                 efi_systab.con_in = systab32->con_in;
 547                 efi_systab.con_out_handle = systab32->con_out_handle;
 548                 efi_systab.con_out = systab32->con_out;
 549                 efi_systab.stderr_handle = systab32->stderr_handle;
 550                 efi_systab.stderr = systab32->stderr;
 551                 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
 552                 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
 553                 efi_systab.nr_tables = systab32->nr_tables;
 554                 efi_systab.tables = systab32->tables;
 555
 556                 early_iounmap(systab32, sizeof(*systab32));
 557         }
 558
 559         efi.systab = &efi_systab;
 560
 561         /*
 562          * Verify the EFI Table
 563          */
 564         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
 565                 pr_err("System table signature incorrect!\n");
 566                 return -EINVAL;
 567         }
 568         if ((efi.systab->hdr.revision >> 16) == 0)
 569                 pr_err("Warning: System table version "
 570                        "%d.%02d, expected 1.00 or greater!\n",
 571                        efi.systab->hdr.revision >> 16,
 572                        efi.systab->hdr.revision & 0xffff);
 573
 574         return 0;
 575 }
 576
 577 static int __init efi_runtime_init(void)
 578 {
 579         efi_runtime_services_t *runtime;
 580
 581         /*
 582          * Check out the runtime services table. We need to map
 583          * the runtime services table so that we can grab the physical
 584          * address of several of the EFI runtime functions, needed to
 585          * set the firmware into virtual mode.
 586          */
 587         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 588                                 sizeof(efi_runtime_services_t));
 589         if (!runtime) {
 590                 pr_err("Could not map the runtime service table!\n");
 591                 return -ENOMEM;
 592         }
 593         /*
 594          * We will only need *early* access to the following
 595          * two EFI runtime services before set_virtual_address_map
 596          * is invoked.
 597          */
 598         efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 599         efi_phys.set_virtual_address_map =
 600                 (efi_set_virtual_address_map_t *)
 601                 runtime->set_virtual_address_map;
 602         /*
 603          * Make efi_get_time can be called before entering
 604          * virtual mode.
 605          */
 606         efi.get_time = phys_efi_get_time;
 607         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 608
 609         return 0;
 610 }
 611
 612 static int __init efi_memmap_init(void)
 613 {
 614         /* Map the EFI memory map */
 615         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 616                                    memmap.nr_map * memmap.desc_size);
 617         if (memmap.map == NULL) {
 618                 pr_err("Could not map the memory map!\n");
 619                 return -ENOMEM;
 620         }
 621         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 622
 623         if (add_efi_memmap)
 624                 do_add_efi_memmap();
 625
 626         return 0;
 627 }
 628
 629 void __init efi_init(void)
 630 {
 631         efi_char16_t *c16;
 632         char vendor[100] = "unknown";
 633         int i = 0;
 634         void *tmp;
 635
 636 #ifdef CONFIG_X86_32
 637         if (boot_params.efi_info.efi_systab_hi ||
 638             boot_params.efi_info.efi_memmap_hi) {
 639                 pr_info("Table located above 4GB, disabling EFI.\n");
 640                 return;
 641         }
 642         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 643 #else
 644         efi_phys.systab = (efi_system_table_t *)
 645                           (boot_params.efi_info.efi_systab |
 646                           ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 647 #endif
 648
 649         if (efi_systab_init(efi_phys.systab))
 650                 return;
 651
 652         set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
 653
 654         /*
 655          * Show what we know for posterity
 656          */
 657         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 658         if (c16) {
 659                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 660                         vendor[i] = *c16++;
 661                 vendor[i] = '\0';
 662         } else
 663                 pr_err("Could not map the firmware vendor!\n");
 664         early_iounmap(tmp, 2);
 665
 666         pr_info("EFI v%u.%.02u by %s\n",
 667                 efi.systab->hdr.revision >> 16,
 668                 efi.systab->hdr.revision & 0xffff, vendor);
 669
 670         if (efi_config_init(arch_tables))
 671                 return;
 672
 673         set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
 674
 675         /*
 676          * Note: We currently don't support runtime services on an EFI
 677          * that doesn't match the kernel 32/64-bit mode.
 678          */
 679
 680         if (!efi_is_native())
 681                 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 682         else {
 683                 if (disable_runtime || efi_runtime_init())
 684                         return;
 685                 set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
 686         }
 687
 688         if (efi_memmap_init())
 689                 return;
 690
 691         set_bit(EFI_MEMMAP, &x86_efi_facility);
 692
 693 #if EFI_DEBUG
 694         print_efi_memmap();
 695 #endif
 696 }
 697
 698 void __init efi_late_init(void)
 699 {
 700         efi_bgrt_init();
 701 }
 702
 703 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 704 {
 705         u64 addr, npages;
 706
 707         addr = md->virt_addr;
 708         npages = md->num_pages;
 709
 710         memrange_efi_to_native(&addr, &npages);
 711
 712         if (executable)
 713                 set_memory_x(addr, npages);
 714         else
 715                 set_memory_nx(addr, npages);
 716 }
 717
 718 static void __init runtime_code_page_mkexec(void)
 719 {
 720         efi_memory_desc_t *md;
 721         void *p;
 722
 723         /* Make EFI runtime service code area executable */
 724         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 725                 md = p;
 726
 727                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 728                         continue;
 729
 730                 efi_set_executable(md, true);
 731         }
 732 }
 733
 734 void efi_memory_uc(u64 addr, unsigned long size)
 735 {
 736         unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
 737         u64 npages;
 738
 739         npages = round_up(size, page_shift) / page_shift;
 740         memrange_efi_to_native(&addr, &npages);
 741         set_memory_uc(addr, npages);
 742 }
 743
 744 /*
 745  * This function will switch the EFI runtime services to virtual mode.
 746  * Essentially, look through the EFI memmap and map every region that
 747  * has the runtime attribute bit set in its memory descriptor and update
 748  * that memory descriptor with the virtual address obtained from ioremap().
 749  * This enables the runtime services to be called without having to
 750  * thunk back into physical mode for every invocation.
 751  */
 752 void __init efi_enter_virtual_mode(void)
 753 {
 754         efi_memory_desc_t *md, *prev_md = NULL;
 755         efi_status_t status;
 756         unsigned long size;
 757         u64 end, systab, start_pfn, end_pfn;
 758         void *p, *va, *new_memmap = NULL;
 759         int count = 0;
 760
 761         efi.systab = NULL;
 762
 763         /*
 764          * We don't do virtual mode, since we don't do runtime services, on
 765          * non-native EFI
 766          */
 767
 768         if (!efi_is_native()) {
 769                 efi_unmap_memmap();
 770                 return;
 771         }
 772
 773         /* Merge contiguous regions of the same type and attribute */
 774         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 775                 u64 prev_size;
 776                 md = p;
 777
 778                 if (!prev_md) {
 779                         prev_md = md;
 780                         continue;
 781                 }
 782
 783                 if (prev_md->type != md->type ||
 784                     prev_md->attribute != md->attribute) {
 785                         prev_md = md;
 786                         continue;
 787                 }
 788
 789                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 790
 791                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 792                         prev_md->num_pages += md->num_pages;
 793                         md->type = EFI_RESERVED_TYPE;
 794                         md->attribute = 0;
 795                         continue;
 796                 }
 797                 prev_md = md;
 798         }
 799
 800         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 801                 md = p;
 802                 if (!(md->attribute & EFI_MEMORY_RUNTIME)) {
 803 #ifdef CONFIG_X86_64
 804                         if (md->type != EFI_BOOT_SERVICES_CODE &&
 805                             md->type != EFI_BOOT_SERVICES_DATA)
 806 #endif
 807                                 continue;
 808                 }
 809
 810                 size = md->num_pages << EFI_PAGE_SHIFT;
 811                 end = md->phys_addr + size;
 812
 813                 start_pfn = PFN_DOWN(md->phys_addr);
 814                 end_pfn = PFN_UP(end);
 815                 if (pfn_range_is_mapped(start_pfn, end_pfn)) {
 816                         va = __va(md->phys_addr);
 817
 818                         if (!(md->attribute & EFI_MEMORY_WB))
 819                                 efi_memory_uc((u64)(unsigned long)va, size);
 820                 } else
 821                         va = efi_ioremap(md->phys_addr, size,
 822                                          md->type, md->attribute);
 823
 824                 md->virt_addr = (u64) (unsigned long) va;
 825
 826                 if (!va) {
 827                         pr_err("ioremap of 0x%llX failed!\n",
 828                                (unsigned long long)md->phys_addr);
 829                         continue;
 830                 }
 831
 832                 systab = (u64) (unsigned long) efi_phys.systab;
 833                 if (md->phys_addr <= systab && systab < end) {
 834                         systab += md->virt_addr - md->phys_addr;
 835                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
 836                 }
 837                 new_memmap = krealloc(new_memmap,
 838                                       (count + 1) * memmap.desc_size,
 839                                       GFP_KERNEL);
 840                 memcpy(new_memmap + (count * memmap.desc_size), md,
 841                        memmap.desc_size);
 842                 count++;
 843         }
 844
 845         BUG_ON(!efi.systab);
 846
 847         status = phys_efi_set_virtual_address_map(
 848                 memmap.desc_size * count,
 849                 memmap.desc_size,
 850                 memmap.desc_version,
 851                 (efi_memory_desc_t *)__pa(new_memmap));
 852
 853         if (status != EFI_SUCCESS) {
 854                 pr_alert("Unable to switch EFI into virtual mode "
 855                          "(status=%lx)!\n", status);
 856                 panic("EFI call to SetVirtualAddressMap() failed!");
 857         }
 858
 859         /*
 860          * Now that EFI is in virtual mode, update the function
 861          * pointers in the runtime service table to the new virtual addresses.
 862          *
 863          * Call EFI services through wrapper functions.
 864          */
 865         efi.runtime_version = efi_systab.hdr.revision;
 866         efi.get_time = virt_efi_get_time;
 867         efi.set_time = virt_efi_set_time;
 868         efi.get_wakeup_time = virt_efi_get_wakeup_time;
 869         efi.set_wakeup_time = virt_efi_set_wakeup_time;
 870         efi.get_variable = virt_efi_get_variable;
 871         efi.get_next_variable = virt_efi_get_next_variable;
 872         efi.set_variable = virt_efi_set_variable;
 873         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
 874         efi.reset_system = virt_efi_reset_system;
 875         efi.set_virtual_address_map = NULL;
 876         efi.query_variable_info = virt_efi_query_variable_info;
 877         efi.update_capsule = virt_efi_update_capsule;
 878         efi.query_capsule_caps = virt_efi_query_capsule_caps;
 879         if (__supported_pte_mask & _PAGE_NX)
 880                 runtime_code_page_mkexec();
 881
 882         kfree(new_memmap);
 883
 884         /* clean DUMMY object */
 885         efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
 886                          EFI_VARIABLE_NON_VOLATILE |
 887                          EFI_VARIABLE_BOOTSERVICE_ACCESS |
 888                          EFI_VARIABLE_RUNTIME_ACCESS,
 889                          0, NULL);
 890 }
 891
 892 /*
 893  * Convenience functions to obtain memory types and attributes
 894  */
 895 u32 efi_mem_type(unsigned long phys_addr)
 896 {
 897         efi_memory_desc_t *md;
 898         void *p;
 899
 900         if (!efi_enabled(EFI_MEMMAP))
 901                 return 0;
 902
 903         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 904                 md = p;
 905                 if ((md->phys_addr <= phys_addr) &&
 906                     (phys_addr < (md->phys_addr +
 907                                   (md->num_pages << EFI_PAGE_SHIFT))))
 908                         return md->type;
 909         }
 910         return 0;
 911 }
 912
 913 u64 efi_mem_attributes(unsigned long phys_addr)
 914 {
 915         efi_memory_desc_t *md;
 916         void *p;
 917
 918         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 919                 md = p;
 920                 if ((md->phys_addr <= phys_addr) &&
 921                     (phys_addr < (md->phys_addr +
 922                                   (md->num_pages << EFI_PAGE_SHIFT))))
 923                         return md->attribute;
 924         }
 925         return 0;
 926 }
 927
 928 /*
 929  * Some firmware has serious problems when using more than 50% of the EFI
 930  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
 931  * we never use more than this safe limit.
 932  *
 933  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
 934  * store.
 935  */
 936 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
 937 {
 938         efi_status_t status;
 939         u64 storage_size, remaining_size, max_size;
 940
 941         if (!(attributes & EFI_VARIABLE_NON_VOLATILE))
 942                 return 0;
 943
 944         status = efi.query_variable_info(attributes, &storage_size,
 945                                          &remaining_size, &max_size);
 946         if (status != EFI_SUCCESS)
 947                 return status;
 948
 949         /*
 950          * Some firmware implementations refuse to boot if there's insufficient
 951          * space in the variable store. We account for that by refusing the
 952          * write if permitting it would reduce the available space to under
 953          * 5KB. This figure was provided by Samsung, so should be safe.
 954          */
 955         if ((remaining_size - size < EFI_MIN_RESERVE) &&
 956                 !efi_no_storage_paranoia) {
 957
 958                 /*
 959                  * Triggering garbage collection may require that the firmware
 960                  * generate a real EFI_OUT_OF_RESOURCES error. We can force
 961                  * that by attempting to use more space than is available.
 962                  */
 963                 unsigned long dummy_size = remaining_size + 1024;
 964                 void *dummy = kzalloc(dummy_size, GFP_ATOMIC);
 965
 966                 if (!dummy)
 967                         return EFI_OUT_OF_RESOURCES;
 968
 969                 status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
 970                                           EFI_VARIABLE_NON_VOLATILE |
 971                                           EFI_VARIABLE_BOOTSERVICE_ACCESS |
 972                                           EFI_VARIABLE_RUNTIME_ACCESS,
 973                                           dummy_size, dummy);
 974
 975                 if (status == EFI_SUCCESS) {
 976                         /*
 977                          * This should have failed, so if it didn't make sure
 978                          * that we delete it...
 979                          */
 980                         efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
 981                                          EFI_VARIABLE_NON_VOLATILE |
 982                                          EFI_VARIABLE_BOOTSERVICE_ACCESS |
 983                                          EFI_VARIABLE_RUNTIME_ACCESS,
 984                                          0, dummy);
 985                 }
 986
 987                 kfree(dummy);
 988
 989                 /*
 990                  * The runtime code may now have triggered a garbage collection
 991                  * run, so check the variable info again
 992                  */
 993                 status = efi.query_variable_info(attributes, &storage_size,
 994                                                  &remaining_size, &max_size);
 995
 996                 if (status != EFI_SUCCESS)
 997                         return status;
 998
 999                 /*
1000                  * There still isn't enough room, so return an error
1001                  */
1002                 if (remaining_size - size < EFI_MIN_RESERVE)
1003                         return EFI_OUT_OF_RESOURCES;
1004         }
1005
1006         return EFI_SUCCESS;
1007 }
1008 EXPORT_SYMBOL_GPL(efi_query_variable_store);