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 #include <linux/ucs2_string.h>
  46
  47 #include <asm/setup.h>
  48 #include <asm/efi.h>
  49 #include <asm/time.h>
  50 #include <asm/cacheflush.h>
  51 #include <asm/tlbflush.h>
  52 #include <asm/x86_init.h>
  53 #include <asm/rtc.h>
  54
  55 #define EFI_DEBUG       1
  56
  57 /*
  58  * There's some additional metadata associated with each
  59  * variable. Intel's reference implementation is 60 bytes - bump that
  60  * to account for potential alignment constraints
  61  */
  62 #define VAR_METADATA_SIZE 64
  63
  64 struct efi __read_mostly efi = {
  65         .mps        = EFI_INVALID_TABLE_ADDR,
  66         .acpi       = EFI_INVALID_TABLE_ADDR,
  67         .acpi20     = EFI_INVALID_TABLE_ADDR,
  68         .smbios     = EFI_INVALID_TABLE_ADDR,
  69         .sal_systab = EFI_INVALID_TABLE_ADDR,
  70         .boot_info  = EFI_INVALID_TABLE_ADDR,
  71         .hcdp       = EFI_INVALID_TABLE_ADDR,
  72         .uga        = EFI_INVALID_TABLE_ADDR,
  73         .uv_systab  = EFI_INVALID_TABLE_ADDR,
  74 };
  75 EXPORT_SYMBOL(efi);
  76
  77 struct efi_memory_map memmap;
  78
  79 static struct efi efi_phys __initdata;
  80 static efi_system_table_t efi_systab __initdata;
  81
  82 static u64 efi_var_store_size;
  83 static u64 efi_var_remaining_size;
  84 static u64 efi_var_max_var_size;
  85 static u64 boot_used_size;
  86 static u64 boot_var_size;
  87 static u64 active_size;
  88
  89 unsigned long x86_efi_facility;
  90
  91 /*
  92  * Returns 1 if 'facility' is enabled, 0 otherwise.
  93  */
  94 int efi_enabled(int facility)
  95 {
  96         return test_bit(facility, &x86_efi_facility) != 0;
  97 }
  98 EXPORT_SYMBOL(efi_enabled);
  99
 100 static bool __initdata disable_runtime = false;
 101 static int __init setup_noefi(char *arg)
 102 {
 103         disable_runtime = true;
 104         return 0;
 105 }
 106 early_param("noefi", setup_noefi);
 107
 108 int add_efi_memmap;
 109 EXPORT_SYMBOL(add_efi_memmap);
 110
 111 static int __init setup_add_efi_memmap(char *arg)
 112 {
 113         add_efi_memmap = 1;
 114         return 0;
 115 }
 116 early_param("add_efi_memmap", setup_add_efi_memmap);
 117
 118 static bool efi_no_storage_paranoia;
 119
 120 static int __init setup_storage_paranoia(char *arg)
 121 {
 122         efi_no_storage_paranoia = true;
 123         return 0;
 124 }
 125 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
 126
 127
 128 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 129 {
 130         unsigned long flags;
 131         efi_status_t status;
 132
 133         spin_lock_irqsave(&rtc_lock, flags);
 134         status = efi_call_virt2(get_time, tm, tc);
 135         spin_unlock_irqrestore(&rtc_lock, flags);
 136         return status;
 137 }
 138
 139 static efi_status_t virt_efi_set_time(efi_time_t *tm)
 140 {
 141         unsigned long flags;
 142         efi_status_t status;
 143
 144         spin_lock_irqsave(&rtc_lock, flags);
 145         status = efi_call_virt1(set_time, tm);
 146         spin_unlock_irqrestore(&rtc_lock, flags);
 147         return status;
 148 }
 149
 150 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
 151                                              efi_bool_t *pending,
 152                                              efi_time_t *tm)
 153 {
 154         unsigned long flags;
 155         efi_status_t status;
 156
 157         spin_lock_irqsave(&rtc_lock, flags);
 158         status = efi_call_virt3(get_wakeup_time,
 159                                 enabled, pending, tm);
 160         spin_unlock_irqrestore(&rtc_lock, flags);
 161         return status;
 162 }
 163
 164 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
 165 {
 166         unsigned long flags;
 167         efi_status_t status;
 168
 169         spin_lock_irqsave(&rtc_lock, flags);
 170         status = efi_call_virt2(set_wakeup_time,
 171                                 enabled, tm);
 172         spin_unlock_irqrestore(&rtc_lock, flags);
 173         return status;
 174 }
 175
 176 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
 177                                           efi_guid_t *vendor,
 178                                           u32 *attr,
 179                                           unsigned long *data_size,
 180                                           void *data)
 181 {
 182         return efi_call_virt5(get_variable,
 183                               name, vendor, attr,
 184                               data_size, data);
 185 }
 186
 187 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 188                                                efi_char16_t *name,
 189                                                efi_guid_t *vendor)
 190 {
 191         efi_status_t status;
 192         static bool finished = false;
 193         static u64 var_size;
 194
 195         status = efi_call_virt3(get_next_variable,
 196                                 name_size, name, vendor);
 197
 198         if (status == EFI_NOT_FOUND) {
 199                 finished = true;
 200                 if (var_size < boot_used_size) {
 201                         boot_var_size = boot_used_size - var_size;
 202                         active_size += boot_var_size;
 203                 } else {
 204                         printk(KERN_WARNING FW_BUG  "efi: Inconsistent initial sizes\n");
 205                 }
 206         }
 207
 208         if (boot_used_size && !finished) {
 209                 unsigned long size;
 210                 u32 attr;
 211                 efi_status_t s;
 212                 void *tmp;
 213
 214                 s = virt_efi_get_variable(name, vendor, &attr, &size, NULL);
 215
 216                 if (s != EFI_BUFFER_TOO_SMALL || !size)
 217                         return status;
 218
 219                 tmp = kmalloc(size, GFP_ATOMIC);
 220
 221                 if (!tmp)
 222                         return status;
 223
 224                 s = virt_efi_get_variable(name, vendor, &attr, &size, tmp);
 225
 226                 if (s == EFI_SUCCESS && (attr & EFI_VARIABLE_NON_VOLATILE)) {
 227                         var_size += size;
 228                         var_size += ucs2_strsize(name, 1024);
 229                         active_size += size;
 230                         active_size += VAR_METADATA_SIZE;
 231                         active_size += ucs2_strsize(name, 1024);
 232                 }
 233
 234                 kfree(tmp);
 235         }
 236
 237         return status;
 238 }
 239
 240 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 241                                           efi_guid_t *vendor,
 242                                           u32 attr,
 243                                           unsigned long data_size,
 244                                           void *data)
 245 {
 246         efi_status_t status;
 247         u32 orig_attr = 0;
 248         unsigned long orig_size = 0;
 249
 250         status = virt_efi_get_variable(name, vendor, &orig_attr, &orig_size,
 251                                        NULL);
 252
 253         if (status != EFI_BUFFER_TOO_SMALL)
 254                 orig_size = 0;
 255
 256         status = efi_call_virt5(set_variable,
 257                                 name, vendor, attr,
 258                                 data_size, data);
 259
 260         if (status == EFI_SUCCESS) {
 261                 if (orig_size) {
 262                         active_size -= orig_size;
 263                         active_size -= ucs2_strsize(name, 1024);
 264                         active_size -= VAR_METADATA_SIZE;
 265                 }
 266                 if (data_size) {
 267                         active_size += data_size;
 268                         active_size += ucs2_strsize(name, 1024);
 269                         active_size += VAR_METADATA_SIZE;
 270                 }
 271         }
 272
 273         return status;
 274 }
 275
 276 static efi_status_t virt_efi_query_variable_info(u32 attr,
 277                                                  u64 *storage_space,
 278                                                  u64 *remaining_space,
 279                                                  u64 *max_variable_size)
 280 {
 281         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 282                 return EFI_UNSUPPORTED;
 283
 284         return efi_call_virt4(query_variable_info, attr, storage_space,
 285                               remaining_space, max_variable_size);
 286 }
 287
 288 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 289 {
 290         return efi_call_virt1(get_next_high_mono_count, count);
 291 }
 292
 293 static void virt_efi_reset_system(int reset_type,
 294                                   efi_status_t status,
 295                                   unsigned long data_size,
 296                                   efi_char16_t *data)
 297 {
 298         efi_call_virt4(reset_system, reset_type, status,
 299                        data_size, data);
 300 }
 301
 302 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
 303                                             unsigned long count,
 304                                             unsigned long sg_list)
 305 {
 306         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 307                 return EFI_UNSUPPORTED;
 308
 309         return efi_call_virt3(update_capsule, capsules, count, sg_list);
 310 }
 311
 312 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
 313                                                 unsigned long count,
 314                                                 u64 *max_size,
 315                                                 int *reset_type)
 316 {
 317         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 318                 return EFI_UNSUPPORTED;
 319
 320         return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
 321                               reset_type);
 322 }
 323
 324 static efi_status_t __init phys_efi_set_virtual_address_map(
 325         unsigned long memory_map_size,
 326         unsigned long descriptor_size,
 327         u32 descriptor_version,
 328         efi_memory_desc_t *virtual_map)
 329 {
 330         efi_status_t status;
 331
 332         efi_call_phys_prelog();
 333         status = efi_call_phys4(efi_phys.set_virtual_address_map,
 334                                 memory_map_size, descriptor_size,
 335                                 descriptor_version, virtual_map);
 336         efi_call_phys_epilog();
 337         return status;
 338 }
 339
 340 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
 341                                              efi_time_cap_t *tc)
 342 {
 343         unsigned long flags;
 344         efi_status_t status;
 345
 346         spin_lock_irqsave(&rtc_lock, flags);
 347         efi_call_phys_prelog();
 348         status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
 349                                 virt_to_phys(tc));
 350         efi_call_phys_epilog();
 351         spin_unlock_irqrestore(&rtc_lock, flags);
 352         return status;
 353 }
 354
 355 int efi_set_rtc_mmss(unsigned long nowtime)
 356 {
 357         efi_status_t    status;
 358         efi_time_t      eft;
 359         efi_time_cap_t  cap;
 360         struct rtc_time tm;
 361
 362         status = efi.get_time(&eft, &cap);
 363         if (status != EFI_SUCCESS) {
 364                 pr_err("Oops: efitime: can't read time!\n");
 365                 return -1;
 366         }
 367
 368         rtc_time_to_tm(nowtime, &tm);
 369         if (!rtc_valid_tm(&tm)) {
 370                 eft.year = tm.tm_year + 1900;
 371                 eft.month = tm.tm_mon + 1;
 372                 eft.day = tm.tm_mday;
 373                 eft.minute = tm.tm_min;
 374                 eft.second = tm.tm_sec;
 375                 eft.nanosecond = 0;
 376         } else {
 377                 printk(KERN_ERR
 378                        "%s: Invalid EFI RTC value: write of %lx to EFI RTC failed\n",
 379                        __FUNCTION__, nowtime);
 380                 return -1;
 381         }
 382
 383         status = efi.set_time(&eft);
 384         if (status != EFI_SUCCESS) {
 385                 pr_err("Oops: efitime: can't write time!\n");
 386                 return -1;
 387         }
 388         return 0;
 389 }
 390
 391 unsigned long efi_get_time(void)
 392 {
 393         efi_status_t status;
 394         efi_time_t eft;
 395         efi_time_cap_t cap;
 396
 397         status = efi.get_time(&eft, &cap);
 398         if (status != EFI_SUCCESS)
 399                 pr_err("Oops: efitime: can't read time!\n");
 400
 401         return mktime(eft.year, eft.month, eft.day, eft.hour,
 402                       eft.minute, eft.second);
 403 }
 404
 405 /*
 406  * Tell the kernel about the EFI memory map.  This might include
 407  * more than the max 128 entries that can fit in the e820 legacy
 408  * (zeropage) memory map.
 409  */
 410
 411 static void __init do_add_efi_memmap(void)
 412 {
 413         void *p;
 414
 415         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 416                 efi_memory_desc_t *md = p;
 417                 unsigned long long start = md->phys_addr;
 418                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 419                 int e820_type;
 420
 421                 switch (md->type) {
 422                 case EFI_LOADER_CODE:
 423                 case EFI_LOADER_DATA:
 424                 case EFI_BOOT_SERVICES_CODE:
 425                 case EFI_BOOT_SERVICES_DATA:
 426                 case EFI_CONVENTIONAL_MEMORY:
 427                         if (md->attribute & EFI_MEMORY_WB)
 428                                 e820_type = E820_RAM;
 429                         else
 430                                 e820_type = E820_RESERVED;
 431                         break;
 432                 case EFI_ACPI_RECLAIM_MEMORY:
 433                         e820_type = E820_ACPI;
 434                         break;
 435                 case EFI_ACPI_MEMORY_NVS:
 436                         e820_type = E820_NVS;
 437                         break;
 438                 case EFI_UNUSABLE_MEMORY:
 439                         e820_type = E820_UNUSABLE;
 440                         break;
 441                 default:
 442                         /*
 443                          * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 444                          * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 445                          * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 446                          */
 447                         e820_type = E820_RESERVED;
 448                         break;
 449                 }
 450                 e820_add_region(start, size, e820_type);
 451         }
 452         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 453 }
 454
 455 int __init efi_memblock_x86_reserve_range(void)
 456 {
 457         struct efi_info *e = &boot_params.efi_info;
 458         unsigned long pmap;
 459
 460 #ifdef CONFIG_X86_32
 461         /* Can't handle data above 4GB at this time */
 462         if (e->efi_memmap_hi) {
 463                 pr_err("Memory map is above 4GB, disabling EFI.\n");
 464                 return -EINVAL;
 465         }
 466         pmap =  e->efi_memmap;
 467 #else
 468         pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
 469 #endif
 470         memmap.phys_map         = (void *)pmap;
 471         memmap.nr_map           = e->efi_memmap_size /
 472                                   e->efi_memdesc_size;
 473         memmap.desc_size        = e->efi_memdesc_size;
 474         memmap.desc_version     = e->efi_memdesc_version;
 475
 476         memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 477
 478         return 0;
 479 }
 480
 481 #if EFI_DEBUG
 482 static void __init print_efi_memmap(void)
 483 {
 484         efi_memory_desc_t *md;
 485         void *p;
 486         int i;
 487
 488         for (p = memmap.map, i = 0;
 489              p < memmap.map_end;
 490              p += memmap.desc_size, i++) {
 491                 md = p;
 492                 pr_info("mem%02u: type=%u, attr=0x%llx, "
 493                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 494                         i, md->type, md->attribute, md->phys_addr,
 495                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 496                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 497         }
 498 }
 499 #endif  /*  EFI_DEBUG  */
 500
 501 void __init efi_reserve_boot_services(void)
 502 {
 503         void *p;
 504
 505         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 506                 efi_memory_desc_t *md = p;
 507                 u64 start = md->phys_addr;
 508                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 509
 510                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 511                     md->type != EFI_BOOT_SERVICES_DATA)
 512                         continue;
 513                 /* Only reserve where possible:
 514                  * - Not within any already allocated areas
 515                  * - Not over any memory area (really needed, if above?)
 516                  * - Not within any part of the kernel
 517                  * - Not the bios reserved area
 518                 */
 519                 if ((start+size >= __pa_symbol(_text)
 520                                 && start <= __pa_symbol(_end)) ||
 521                         !e820_all_mapped(start, start+size, E820_RAM) ||
 522                         memblock_is_region_reserved(start, size)) {
 523                         /* Could not reserve, skip it */
 524                         md->num_pages = 0;
 525                         memblock_dbg("Could not reserve boot range "
 526                                         "[0x%010llx-0x%010llx]\n",
 527                                                 start, start+size-1);
 528                 } else
 529                         memblock_reserve(start, size);
 530         }
 531 }
 532
 533 void __init efi_unmap_memmap(void)
 534 {
 535         clear_bit(EFI_MEMMAP, &x86_efi_facility);
 536         if (memmap.map) {
 537                 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 538                 memmap.map = NULL;
 539         }
 540 }
 541
 542 void __init efi_free_boot_services(void)
 543 {
 544         void *p;
 545
 546         if (!efi_is_native())
 547                 return;
 548
 549         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 550                 efi_memory_desc_t *md = p;
 551                 unsigned long long start = md->phys_addr;
 552                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 553
 554                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 555                     md->type != EFI_BOOT_SERVICES_DATA)
 556                         continue;
 557
 558                 /* Could not reserve boot area */
 559                 if (!size)
 560                         continue;
 561
 562                 free_bootmem_late(start, size);
 563         }
 564
 565         efi_unmap_memmap();
 566 }
 567
 568 static int __init efi_systab_init(void *phys)
 569 {
 570         if (efi_enabled(EFI_64BIT)) {
 571                 efi_system_table_64_t *systab64;
 572                 u64 tmp = 0;
 573
 574                 systab64 = early_ioremap((unsigned long)phys,
 575                                          sizeof(*systab64));
 576                 if (systab64 == NULL) {
 577                         pr_err("Couldn't map the system table!\n");
 578                         return -ENOMEM;
 579                 }
 580
 581                 efi_systab.hdr = systab64->hdr;
 582                 efi_systab.fw_vendor = systab64->fw_vendor;
 583                 tmp |= systab64->fw_vendor;
 584                 efi_systab.fw_revision = systab64->fw_revision;
 585                 efi_systab.con_in_handle = systab64->con_in_handle;
 586                 tmp |= systab64->con_in_handle;
 587                 efi_systab.con_in = systab64->con_in;
 588                 tmp |= systab64->con_in;
 589                 efi_systab.con_out_handle = systab64->con_out_handle;
 590                 tmp |= systab64->con_out_handle;
 591                 efi_systab.con_out = systab64->con_out;
 592                 tmp |= systab64->con_out;
 593                 efi_systab.stderr_handle = systab64->stderr_handle;
 594                 tmp |= systab64->stderr_handle;
 595                 efi_systab.stderr = systab64->stderr;
 596                 tmp |= systab64->stderr;
 597                 efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
 598                 tmp |= systab64->runtime;
 599                 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
 600                 tmp |= systab64->boottime;
 601                 efi_systab.nr_tables = systab64->nr_tables;
 602                 efi_systab.tables = systab64->tables;
 603                 tmp |= systab64->tables;
 604
 605                 early_iounmap(systab64, sizeof(*systab64));
 606 #ifdef CONFIG_X86_32
 607                 if (tmp >> 32) {
 608                         pr_err("EFI data located above 4GB, disabling EFI.\n");
 609                         return -EINVAL;
 610                 }
 611 #endif
 612         } else {
 613                 efi_system_table_32_t *systab32;
 614
 615                 systab32 = early_ioremap((unsigned long)phys,
 616                                          sizeof(*systab32));
 617                 if (systab32 == NULL) {
 618                         pr_err("Couldn't map the system table!\n");
 619                         return -ENOMEM;
 620                 }
 621
 622                 efi_systab.hdr = systab32->hdr;
 623                 efi_systab.fw_vendor = systab32->fw_vendor;
 624                 efi_systab.fw_revision = systab32->fw_revision;
 625                 efi_systab.con_in_handle = systab32->con_in_handle;
 626                 efi_systab.con_in = systab32->con_in;
 627                 efi_systab.con_out_handle = systab32->con_out_handle;
 628                 efi_systab.con_out = systab32->con_out;
 629                 efi_systab.stderr_handle = systab32->stderr_handle;
 630                 efi_systab.stderr = systab32->stderr;
 631                 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
 632                 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
 633                 efi_systab.nr_tables = systab32->nr_tables;
 634                 efi_systab.tables = systab32->tables;
 635
 636                 early_iounmap(systab32, sizeof(*systab32));
 637         }
 638
 639         efi.systab = &efi_systab;
 640
 641         /*
 642          * Verify the EFI Table
 643          */
 644         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
 645                 pr_err("System table signature incorrect!\n");
 646                 return -EINVAL;
 647         }
 648         if ((efi.systab->hdr.revision >> 16) == 0)
 649                 pr_err("Warning: System table version "
 650                        "%d.%02d, expected 1.00 or greater!\n",
 651                        efi.systab->hdr.revision >> 16,
 652                        efi.systab->hdr.revision & 0xffff);
 653
 654         return 0;
 655 }
 656
 657 static int __init efi_config_init(u64 tables, int nr_tables)
 658 {
 659         void *config_tables, *tablep;
 660         int i, sz;
 661
 662         if (efi_enabled(EFI_64BIT))
 663                 sz = sizeof(efi_config_table_64_t);
 664         else
 665                 sz = sizeof(efi_config_table_32_t);
 666
 667         /*
 668          * Let's see what config tables the firmware passed to us.
 669          */
 670         config_tables = early_ioremap(tables, nr_tables * sz);
 671         if (config_tables == NULL) {
 672                 pr_err("Could not map Configuration table!\n");
 673                 return -ENOMEM;
 674         }
 675
 676         tablep = config_tables;
 677         pr_info("");
 678         for (i = 0; i < efi.systab->nr_tables; i++) {
 679                 efi_guid_t guid;
 680                 unsigned long table;
 681
 682                 if (efi_enabled(EFI_64BIT)) {
 683                         u64 table64;
 684                         guid = ((efi_config_table_64_t *)tablep)->guid;
 685                         table64 = ((efi_config_table_64_t *)tablep)->table;
 686                         table = table64;
 687 #ifdef CONFIG_X86_32
 688                         if (table64 >> 32) {
 689                                 pr_cont("\n");
 690                                 pr_err("Table located above 4GB, disabling EFI.\n");
 691                                 early_iounmap(config_tables,
 692                                               efi.systab->nr_tables * sz);
 693                                 return -EINVAL;
 694                         }
 695 #endif
 696                 } else {
 697                         guid = ((efi_config_table_32_t *)tablep)->guid;
 698                         table = ((efi_config_table_32_t *)tablep)->table;
 699                 }
 700                 if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
 701                         efi.mps = table;
 702                         pr_cont(" MPS=0x%lx ", table);
 703                 } else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
 704                         efi.acpi20 = table;
 705                         pr_cont(" ACPI 2.0=0x%lx ", table);
 706                 } else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
 707                         efi.acpi = table;
 708                         pr_cont(" ACPI=0x%lx ", table);
 709                 } else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
 710                         efi.smbios = table;
 711                         pr_cont(" SMBIOS=0x%lx ", table);
 712 #ifdef CONFIG_X86_UV
 713                 } else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
 714                         efi.uv_systab = table;
 715                         pr_cont(" UVsystab=0x%lx ", table);
 716 #endif
 717                 } else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
 718                         efi.hcdp = table;
 719                         pr_cont(" HCDP=0x%lx ", table);
 720                 } else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
 721                         efi.uga = table;
 722                         pr_cont(" UGA=0x%lx ", table);
 723                 }
 724                 tablep += sz;
 725         }
 726         pr_cont("\n");
 727         early_iounmap(config_tables, efi.systab->nr_tables * sz);
 728         return 0;
 729 }
 730
 731 static int __init efi_runtime_init(void)
 732 {
 733         efi_runtime_services_t *runtime;
 734
 735         /*
 736          * Check out the runtime services table. We need to map
 737          * the runtime services table so that we can grab the physical
 738          * address of several of the EFI runtime functions, needed to
 739          * set the firmware into virtual mode.
 740          */
 741         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 742                                 sizeof(efi_runtime_services_t));
 743         if (!runtime) {
 744                 pr_err("Could not map the runtime service table!\n");
 745                 return -ENOMEM;
 746         }
 747         /*
 748          * We will only need *early* access to the following
 749          * two EFI runtime services before set_virtual_address_map
 750          * is invoked.
 751          */
 752         efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 753         efi_phys.set_virtual_address_map =
 754                 (efi_set_virtual_address_map_t *)
 755                 runtime->set_virtual_address_map;
 756         /*
 757          * Make efi_get_time can be called before entering
 758          * virtual mode.
 759          */
 760         efi.get_time = phys_efi_get_time;
 761         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 762
 763         return 0;
 764 }
 765
 766 static int __init efi_memmap_init(void)
 767 {
 768         /* Map the EFI memory map */
 769         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 770                                    memmap.nr_map * memmap.desc_size);
 771         if (memmap.map == NULL) {
 772                 pr_err("Could not map the memory map!\n");
 773                 return -ENOMEM;
 774         }
 775         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 776
 777         if (add_efi_memmap)
 778                 do_add_efi_memmap();
 779
 780         return 0;
 781 }
 782
 783 void __init efi_init(void)
 784 {
 785         efi_char16_t *c16;
 786         char vendor[100] = "unknown";
 787         int i = 0;
 788         void *tmp;
 789         struct setup_data *data;
 790         struct efi_var_bootdata *efi_var_data;
 791         u64 pa_data;
 792
 793 #ifdef CONFIG_X86_32
 794         if (boot_params.efi_info.efi_systab_hi ||
 795             boot_params.efi_info.efi_memmap_hi) {
 796                 pr_info("Table located above 4GB, disabling EFI.\n");
 797                 return;
 798         }
 799         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 800 #else
 801         efi_phys.systab = (efi_system_table_t *)
 802                           (boot_params.efi_info.efi_systab |
 803                           ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 804 #endif
 805
 806         if (efi_systab_init(efi_phys.systab))
 807                 return;
 808
 809         pa_data = boot_params.hdr.setup_data;
 810         while (pa_data) {
 811                 data = early_ioremap(pa_data, sizeof(*efi_var_data));
 812                 if (data->type == SETUP_EFI_VARS) {
 813                         efi_var_data = (struct efi_var_bootdata *)data;
 814
 815                         efi_var_store_size = efi_var_data->store_size;
 816                         efi_var_remaining_size = efi_var_data->remaining_size;
 817                         efi_var_max_var_size = efi_var_data->max_var_size;
 818                 }
 819                 pa_data = data->next;
 820                 early_iounmap(data, sizeof(*efi_var_data));
 821         }
 822
 823         boot_used_size = efi_var_store_size - efi_var_remaining_size;
 824
 825         set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
 826
 827         /*
 828          * Show what we know for posterity
 829          */
 830         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 831         if (c16) {
 832                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 833                         vendor[i] = *c16++;
 834                 vendor[i] = '\0';
 835         } else
 836                 pr_err("Could not map the firmware vendor!\n");
 837         early_iounmap(tmp, 2);
 838
 839         pr_info("EFI v%u.%.02u by %s\n",
 840                 efi.systab->hdr.revision >> 16,
 841                 efi.systab->hdr.revision & 0xffff, vendor);
 842
 843         if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
 844                 return;
 845
 846         set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
 847
 848         /*
 849          * Note: We currently don't support runtime services on an EFI
 850          * that doesn't match the kernel 32/64-bit mode.
 851          */
 852
 853         if (!efi_is_native())
 854                 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 855         else {
 856                 if (disable_runtime || efi_runtime_init())
 857                         return;
 858                 set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
 859         }
 860
 861         if (efi_memmap_init())
 862                 return;
 863
 864         set_bit(EFI_MEMMAP, &x86_efi_facility);
 865
 866 #ifdef CONFIG_X86_32
 867         if (efi_is_native()) {
 868                 x86_platform.get_wallclock = efi_get_time;
 869                 x86_platform.set_wallclock = efi_set_rtc_mmss;
 870         }
 871 #endif
 872
 873 #if EFI_DEBUG
 874         print_efi_memmap();
 875 #endif
 876 }
 877
 878 void __init efi_late_init(void)
 879 {
 880         efi_bgrt_init();
 881 }
 882
 883 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 884 {
 885         u64 addr, npages;
 886
 887         addr = md->virt_addr;
 888         npages = md->num_pages;
 889
 890         memrange_efi_to_native(&addr, &npages);
 891
 892         if (executable)
 893                 set_memory_x(addr, npages);
 894         else
 895                 set_memory_nx(addr, npages);
 896 }
 897
 898 static void __init runtime_code_page_mkexec(void)
 899 {
 900         efi_memory_desc_t *md;
 901         void *p;
 902
 903         /* Make EFI runtime service code area executable */
 904         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 905                 md = p;
 906
 907                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 908                         continue;
 909
 910                 efi_set_executable(md, true);
 911         }
 912 }
 913
 914 /*
 915  * We can't ioremap data in EFI boot services RAM, because we've already mapped
 916  * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
 917  * callable after efi_enter_virtual_mode and before efi_free_boot_services.
 918  */
 919 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
 920 {
 921         void *p;
 922         if (WARN_ON(!memmap.map))
 923                 return NULL;
 924         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 925                 efi_memory_desc_t *md = p;
 926                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 927                 u64 end = md->phys_addr + size;
 928                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 929                     md->type != EFI_BOOT_SERVICES_CODE &&
 930                     md->type != EFI_BOOT_SERVICES_DATA)
 931                         continue;
 932                 if (!md->virt_addr)
 933                         continue;
 934                 if (phys_addr >= md->phys_addr && phys_addr < end) {
 935                         phys_addr += md->virt_addr - md->phys_addr;
 936                         return (__force void __iomem *)(unsigned long)phys_addr;
 937                 }
 938         }
 939         return NULL;
 940 }
 941
 942 void efi_memory_uc(u64 addr, unsigned long size)
 943 {
 944         unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
 945         u64 npages;
 946
 947         npages = round_up(size, page_shift) / page_shift;
 948         memrange_efi_to_native(&addr, &npages);
 949         set_memory_uc(addr, npages);
 950 }
 951
 952 /*
 953  * This function will switch the EFI runtime services to virtual mode.
 954  * Essentially, look through the EFI memmap and map every region that
 955  * has the runtime attribute bit set in its memory descriptor and update
 956  * that memory descriptor with the virtual address obtained from ioremap().
 957  * This enables the runtime services to be called without having to
 958  * thunk back into physical mode for every invocation.
 959  */
 960 void __init efi_enter_virtual_mode(void)
 961 {
 962         efi_memory_desc_t *md, *prev_md = NULL;
 963         efi_status_t status;
 964         unsigned long size;
 965         u64 end, systab, start_pfn, end_pfn;
 966         void *p, *va, *new_memmap = NULL;
 967         int count = 0;
 968
 969         efi.systab = NULL;
 970
 971         /*
 972          * We don't do virtual mode, since we don't do runtime services, on
 973          * non-native EFI
 974          */
 975
 976         if (!efi_is_native()) {
 977                 efi_unmap_memmap();
 978                 return;
 979         }
 980
 981         /* Merge contiguous regions of the same type and attribute */
 982         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 983                 u64 prev_size;
 984                 md = p;
 985
 986                 if (!prev_md) {
 987                         prev_md = md;
 988                         continue;
 989                 }
 990
 991                 if (prev_md->type != md->type ||
 992                     prev_md->attribute != md->attribute) {
 993                         prev_md = md;
 994                         continue;
 995                 }
 996
 997                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 998
 999                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
1000                         prev_md->num_pages += md->num_pages;
1001                         md->type = EFI_RESERVED_TYPE;
1002                         md->attribute = 0;
1003                         continue;
1004                 }
1005                 prev_md = md;
1006         }
1007
1008         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1009                 md = p;
1010                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
1011                     md->type != EFI_BOOT_SERVICES_CODE &&
1012                     md->type != EFI_BOOT_SERVICES_DATA)
1013                         continue;
1014
1015                 size = md->num_pages << EFI_PAGE_SHIFT;
1016                 end = md->phys_addr + size;
1017
1018                 start_pfn = PFN_DOWN(md->phys_addr);
1019                 end_pfn = PFN_UP(end);
1020                 if (pfn_range_is_mapped(start_pfn, end_pfn)) {
1021                         va = __va(md->phys_addr);
1022
1023                         if (!(md->attribute & EFI_MEMORY_WB))
1024                                 efi_memory_uc((u64)(unsigned long)va, size);
1025                 } else
1026                         va = efi_ioremap(md->phys_addr, size,
1027                                          md->type, md->attribute);
1028
1029                 md->virt_addr = (u64) (unsigned long) va;
1030
1031                 if (!va) {
1032                         pr_err("ioremap of 0x%llX failed!\n",
1033                                (unsigned long long)md->phys_addr);
1034                         continue;
1035                 }
1036
1037                 systab = (u64) (unsigned long) efi_phys.systab;
1038                 if (md->phys_addr <= systab && systab < end) {
1039                         systab += md->virt_addr - md->phys_addr;
1040                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
1041                 }
1042                 new_memmap = krealloc(new_memmap,
1043                                       (count + 1) * memmap.desc_size,
1044                                       GFP_KERNEL);
1045                 memcpy(new_memmap + (count * memmap.desc_size), md,
1046                        memmap.desc_size);
1047                 count++;
1048         }
1049
1050         BUG_ON(!efi.systab);
1051
1052         status = phys_efi_set_virtual_address_map(
1053                 memmap.desc_size * count,
1054                 memmap.desc_size,
1055                 memmap.desc_version,
1056                 (efi_memory_desc_t *)__pa(new_memmap));
1057
1058         if (status != EFI_SUCCESS) {
1059                 pr_alert("Unable to switch EFI into virtual mode "
1060                          "(status=%lx)!\n", status);
1061                 panic("EFI call to SetVirtualAddressMap() failed!");
1062         }
1063
1064         /*
1065          * Now that EFI is in virtual mode, update the function
1066          * pointers in the runtime service table to the new virtual addresses.
1067          *
1068          * Call EFI services through wrapper functions.
1069          */
1070         efi.runtime_version = efi_systab.hdr.revision;
1071         efi.get_time = virt_efi_get_time;
1072         efi.set_time = virt_efi_set_time;
1073         efi.get_wakeup_time = virt_efi_get_wakeup_time;
1074         efi.set_wakeup_time = virt_efi_set_wakeup_time;
1075         efi.get_variable = virt_efi_get_variable;
1076         efi.get_next_variable = virt_efi_get_next_variable;
1077         efi.set_variable = virt_efi_set_variable;
1078         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
1079         efi.reset_system = virt_efi_reset_system;
1080         efi.set_virtual_address_map = NULL;
1081         efi.query_variable_info = virt_efi_query_variable_info;
1082         efi.update_capsule = virt_efi_update_capsule;
1083         efi.query_capsule_caps = virt_efi_query_capsule_caps;
1084         if (__supported_pte_mask & _PAGE_NX)
1085                 runtime_code_page_mkexec();
1086
1087         kfree(new_memmap);
1088 }
1089
1090 /*
1091  * Convenience functions to obtain memory types and attributes
1092  */
1093 u32 efi_mem_type(unsigned long phys_addr)
1094 {
1095         efi_memory_desc_t *md;
1096         void *p;
1097
1098         if (!efi_enabled(EFI_MEMMAP))
1099                 return 0;
1100
1101         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1102                 md = p;
1103                 if ((md->phys_addr <= phys_addr) &&
1104                     (phys_addr < (md->phys_addr +
1105                                   (md->num_pages << EFI_PAGE_SHIFT))))
1106                         return md->type;
1107         }
1108         return 0;
1109 }
1110
1111 u64 efi_mem_attributes(unsigned long phys_addr)
1112 {
1113         efi_memory_desc_t *md;
1114         void *p;
1115
1116         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1117                 md = p;
1118                 if ((md->phys_addr <= phys_addr) &&
1119                     (phys_addr < (md->phys_addr +
1120                                   (md->num_pages << EFI_PAGE_SHIFT))))
1121                         return md->attribute;
1122         }
1123         return 0;
1124 }
1125
1126 /*
1127  * Some firmware has serious problems when using more than 50% of the EFI
1128  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
1129  * we never use more than this safe limit.
1130  *
1131  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
1132  * store.
1133  */
1134 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
1135 {
1136         efi_status_t status;
1137         u64 storage_size, remaining_size, max_size;
1138
1139         status = efi.query_variable_info(attributes, &storage_size,
1140                                          &remaining_size, &max_size);
1141         if (status != EFI_SUCCESS)
1142                 return status;
1143
1144         if (!max_size && remaining_size > size)
1145                 printk_once(KERN_ERR FW_BUG "Broken EFI implementation"
1146                             " is returning MaxVariableSize=0\n");
1147         /*
1148          * Some firmware implementations refuse to boot if there's insufficient
1149          * space in the variable store. We account for that by refusing the
1150          * write if permitting it would reduce the available space to under
1151          * 50%. However, some firmware won't reclaim variable space until
1152          * after the used (not merely the actively used) space drops below
1153          * a threshold. We can approximate that case with the value calculated
1154          * above. If both the firmware and our calculations indicate that the
1155          * available space would drop below 50%, refuse the write.
1156          */
1157
1158         if (!storage_size || size > remaining_size ||
1159             (max_size && size > max_size))
1160                 return EFI_OUT_OF_RESOURCES;
1161
1162         if (!efi_no_storage_paranoia &&
1163             ((active_size + size + VAR_METADATA_SIZE > storage_size / 2) &&
1164              (remaining_size - size < storage_size / 2)))
1165                 return EFI_OUT_OF_RESOURCES;
1166
1167         return EFI_SUCCESS;
1168 }
1169 EXPORT_SYMBOL_GPL(efi_query_variable_store);