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/memblock.h>
  38 #include <linux/spinlock.h>
  39 #include <linux/uaccess.h>
  40 #include <linux/time.h>
  41 #include <linux/io.h>
  42 #include <linux/reboot.h>
  43 #include <linux/bcd.h>
  44 #include <linux/ucs2_string.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
  53 #define EFI_DEBUG       1
  54
  55 /*
  56  * There's some additional metadata associated with each
  57  * variable. Intel's reference implementation is 60 bytes - bump that
  58  * to account for potential alignment constraints
  59  */
  60 #define VAR_METADATA_SIZE 64
  61
  62 struct efi __read_mostly efi = {
  63         .mps        = EFI_INVALID_TABLE_ADDR,
  64         .acpi       = EFI_INVALID_TABLE_ADDR,
  65         .acpi20     = EFI_INVALID_TABLE_ADDR,
  66         .smbios     = EFI_INVALID_TABLE_ADDR,
  67         .sal_systab = EFI_INVALID_TABLE_ADDR,
  68         .boot_info  = EFI_INVALID_TABLE_ADDR,
  69         .hcdp       = EFI_INVALID_TABLE_ADDR,
  70         .uga        = EFI_INVALID_TABLE_ADDR,
  71         .uv_systab  = EFI_INVALID_TABLE_ADDR,
  72 };
  73 EXPORT_SYMBOL(efi);
  74
  75 struct efi_memory_map memmap;
  76
  77 static struct efi efi_phys __initdata;
  78 static efi_system_table_t efi_systab __initdata;
  79
  80 static u64 efi_var_store_size;
  81 static u64 efi_var_remaining_size;
  82 static u64 efi_var_max_var_size;
  83 static u64 boot_used_size;
  84 static u64 boot_var_size;
  85 static u64 active_size;
  86
  87 unsigned long x86_efi_facility;
  88
  89 /*
  90  * Returns 1 if 'facility' is enabled, 0 otherwise.
  91  */
  92 int efi_enabled(int facility)
  93 {
  94         return test_bit(facility, &x86_efi_facility) != 0;
  95 }
  96 EXPORT_SYMBOL(efi_enabled);
  97
  98 static bool __initdata disable_runtime = false;
  99 static int __init setup_noefi(char *arg)
 100 {
 101         disable_runtime = true;
 102         return 0;
 103 }
 104 early_param("noefi", setup_noefi);
 105
 106 int add_efi_memmap;
 107 EXPORT_SYMBOL(add_efi_memmap);
 108
 109 static int __init setup_add_efi_memmap(char *arg)
 110 {
 111         add_efi_memmap = 1;
 112         return 0;
 113 }
 114 early_param("add_efi_memmap", setup_add_efi_memmap);
 115
 116 static bool efi_no_storage_paranoia;
 117
 118 static int __init setup_storage_paranoia(char *arg)
 119 {
 120         efi_no_storage_paranoia = true;
 121         return 0;
 122 }
 123 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
 124
 125
 126 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 127 {
 128         unsigned long flags;
 129         efi_status_t status;
 130
 131         spin_lock_irqsave(&rtc_lock, flags);
 132         status = efi_call_virt2(get_time, tm, tc);
 133         spin_unlock_irqrestore(&rtc_lock, flags);
 134         return status;
 135 }
 136
 137 static efi_status_t virt_efi_set_time(efi_time_t *tm)
 138 {
 139         unsigned long flags;
 140         efi_status_t status;
 141
 142         spin_lock_irqsave(&rtc_lock, flags);
 143         status = efi_call_virt1(set_time, tm);
 144         spin_unlock_irqrestore(&rtc_lock, flags);
 145         return status;
 146 }
 147
 148 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
 149                                              efi_bool_t *pending,
 150                                              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_virt3(get_wakeup_time,
 157                                 enabled, pending, tm);
 158         spin_unlock_irqrestore(&rtc_lock, flags);
 159         return status;
 160 }
 161
 162 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
 163 {
 164         unsigned long flags;
 165         efi_status_t status;
 166
 167         spin_lock_irqsave(&rtc_lock, flags);
 168         status = efi_call_virt2(set_wakeup_time,
 169                                 enabled, tm);
 170         spin_unlock_irqrestore(&rtc_lock, flags);
 171         return status;
 172 }
 173
 174 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
 175                                           efi_guid_t *vendor,
 176                                           u32 *attr,
 177                                           unsigned long *data_size,
 178                                           void *data)
 179 {
 180         return efi_call_virt5(get_variable,
 181                               name, vendor, attr,
 182                               data_size, data);
 183 }
 184
 185 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 186                                                efi_char16_t *name,
 187                                                efi_guid_t *vendor)
 188 {
 189         efi_status_t status;
 190         static bool finished = false;
 191         static u64 var_size;
 192
 193         status = efi_call_virt3(get_next_variable,
 194                                 name_size, name, vendor);
 195
 196         if (status == EFI_NOT_FOUND) {
 197                 finished = true;
 198                 if (var_size < boot_used_size) {
 199                         boot_var_size = boot_used_size - var_size;
 200                         active_size += boot_var_size;
 201                 } else {
 202                         printk(KERN_WARNING FW_BUG  "efi: Inconsistent initial sizes\n");
 203                 }
 204         }
 205
 206         if (boot_used_size && !finished) {
 207                 unsigned long size;
 208                 u32 attr;
 209                 efi_status_t s;
 210                 void *tmp;
 211
 212                 s = virt_efi_get_variable(name, vendor, &attr, &size, NULL);
 213
 214                 if (s != EFI_BUFFER_TOO_SMALL || !size)
 215                         return status;
 216
 217                 tmp = kmalloc(size, GFP_ATOMIC);
 218
 219                 if (!tmp)
 220                         return status;
 221
 222                 s = virt_efi_get_variable(name, vendor, &attr, &size, tmp);
 223
 224                 if (s == EFI_SUCCESS && (attr & EFI_VARIABLE_NON_VOLATILE)) {
 225                         var_size += size;
 226                         var_size += ucs2_strsize(name, 1024);
 227                         active_size += size;
 228                         active_size += VAR_METADATA_SIZE;
 229                         active_size += ucs2_strsize(name, 1024);
 230                 }
 231
 232                 kfree(tmp);
 233         }
 234
 235         return status;
 236 }
 237
 238 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 239                                           efi_guid_t *vendor,
 240                                           u32 attr,
 241                                           unsigned long data_size,
 242                                           void *data)
 243 {
 244         efi_status_t status;
 245         u32 orig_attr = 0;
 246         unsigned long orig_size = 0;
 247
 248         status = virt_efi_get_variable(name, vendor, &orig_attr, &orig_size,
 249                                        NULL);
 250
 251         if (status != EFI_BUFFER_TOO_SMALL)
 252                 orig_size = 0;
 253
 254         status = efi_call_virt5(set_variable,
 255                                 name, vendor, attr,
 256                                 data_size, data);
 257
 258         if (status == EFI_SUCCESS) {
 259                 if (orig_size) {
 260                         active_size -= orig_size;
 261                         active_size -= ucs2_strsize(name, 1024);
 262                         active_size -= VAR_METADATA_SIZE;
 263                 }
 264                 if (data_size) {
 265                         active_size += data_size;
 266                         active_size += ucs2_strsize(name, 1024);
 267                         active_size += VAR_METADATA_SIZE;
 268                 }
 269         }
 270
 271         return status;
 272 }
 273
 274 static efi_status_t virt_efi_query_variable_info(u32 attr,
 275                                                  u64 *storage_space,
 276                                                  u64 *remaining_space,
 277                                                  u64 *max_variable_size)
 278 {
 279         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 280                 return EFI_UNSUPPORTED;
 281
 282         return efi_call_virt4(query_variable_info, attr, storage_space,
 283                               remaining_space, max_variable_size);
 284 }
 285
 286 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 287 {
 288         return efi_call_virt1(get_next_high_mono_count, count);
 289 }
 290
 291 static void virt_efi_reset_system(int reset_type,
 292                                   efi_status_t status,
 293                                   unsigned long data_size,
 294                                   efi_char16_t *data)
 295 {
 296         efi_call_virt4(reset_system, reset_type, status,
 297                        data_size, data);
 298 }
 299
 300 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
 301                                             unsigned long count,
 302                                             unsigned long sg_list)
 303 {
 304         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 305                 return EFI_UNSUPPORTED;
 306
 307         return efi_call_virt3(update_capsule, capsules, count, sg_list);
 308 }
 309
 310 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
 311                                                 unsigned long count,
 312                                                 u64 *max_size,
 313                                                 int *reset_type)
 314 {
 315         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 316                 return EFI_UNSUPPORTED;
 317
 318         return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
 319                               reset_type);
 320 }
 321
 322 static efi_status_t __init phys_efi_set_virtual_address_map(
 323         unsigned long memory_map_size,
 324         unsigned long descriptor_size,
 325         u32 descriptor_version,
 326         efi_memory_desc_t *virtual_map)
 327 {
 328         efi_status_t status;
 329
 330         efi_call_phys_prelog();
 331         status = efi_call_phys4(efi_phys.set_virtual_address_map,
 332                                 memory_map_size, descriptor_size,
 333                                 descriptor_version, virtual_map);
 334         efi_call_phys_epilog();
 335         return status;
 336 }
 337
 338 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
 339                                              efi_time_cap_t *tc)
 340 {
 341         unsigned long flags;
 342         efi_status_t status;
 343
 344         spin_lock_irqsave(&rtc_lock, flags);
 345         efi_call_phys_prelog();
 346         status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
 347                                 virt_to_phys(tc));
 348         efi_call_phys_epilog();
 349         spin_unlock_irqrestore(&rtc_lock, flags);
 350         return status;
 351 }
 352
 353 int efi_set_rtc_mmss(unsigned long nowtime)
 354 {
 355         int real_seconds, real_minutes;
 356         efi_status_t    status;
 357         efi_time_t      eft;
 358         efi_time_cap_t  cap;
 359
 360         status = efi.get_time(&eft, &cap);
 361         if (status != EFI_SUCCESS) {
 362                 pr_err("Oops: efitime: can't read time!\n");
 363                 return -1;
 364         }
 365
 366         real_seconds = nowtime % 60;
 367         real_minutes = nowtime / 60;
 368         if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
 369                 real_minutes += 30;
 370         real_minutes %= 60;
 371         eft.minute = real_minutes;
 372         eft.second = real_seconds;
 373
 374         status = efi.set_time(&eft);
 375         if (status != EFI_SUCCESS) {
 376                 pr_err("Oops: efitime: can't write time!\n");
 377                 return -1;
 378         }
 379         return 0;
 380 }
 381
 382 unsigned long efi_get_time(void)
 383 {
 384         efi_status_t status;
 385         efi_time_t eft;
 386         efi_time_cap_t cap;
 387
 388         status = efi.get_time(&eft, &cap);
 389         if (status != EFI_SUCCESS)
 390                 pr_err("Oops: efitime: can't read time!\n");
 391
 392         return mktime(eft.year, eft.month, eft.day, eft.hour,
 393                       eft.minute, eft.second);
 394 }
 395
 396 /*
 397  * Tell the kernel about the EFI memory map.  This might include
 398  * more than the max 128 entries that can fit in the e820 legacy
 399  * (zeropage) memory map.
 400  */
 401
 402 static void __init do_add_efi_memmap(void)
 403 {
 404         void *p;
 405
 406         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 407                 efi_memory_desc_t *md = p;
 408                 unsigned long long start = md->phys_addr;
 409                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 410                 int e820_type;
 411
 412                 switch (md->type) {
 413                 case EFI_LOADER_CODE:
 414                 case EFI_LOADER_DATA:
 415                 case EFI_BOOT_SERVICES_CODE:
 416                 case EFI_BOOT_SERVICES_DATA:
 417                 case EFI_CONVENTIONAL_MEMORY:
 418                         if (md->attribute & EFI_MEMORY_WB)
 419                                 e820_type = E820_RAM;
 420                         else
 421                                 e820_type = E820_RESERVED;
 422                         break;
 423                 case EFI_ACPI_RECLAIM_MEMORY:
 424                         e820_type = E820_ACPI;
 425                         break;
 426                 case EFI_ACPI_MEMORY_NVS:
 427                         e820_type = E820_NVS;
 428                         break;
 429                 case EFI_UNUSABLE_MEMORY:
 430                         e820_type = E820_UNUSABLE;
 431                         break;
 432                 default:
 433                         /*
 434                          * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 435                          * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 436                          * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 437                          */
 438                         e820_type = E820_RESERVED;
 439                         break;
 440                 }
 441                 e820_add_region(start, size, e820_type);
 442         }
 443         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 444 }
 445
 446 int __init efi_memblock_x86_reserve_range(void)
 447 {
 448         struct efi_info *e = &boot_params.efi_info;
 449         unsigned long pmap;
 450
 451 #ifdef CONFIG_X86_32
 452         /* Can't handle data above 4GB at this time */
 453         if (e->efi_memmap_hi) {
 454                 pr_err("Memory map is above 4GB, disabling EFI.\n");
 455                 return -EINVAL;
 456         }
 457         pmap =  e->efi_memmap;
 458 #else
 459         pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
 460 #endif
 461         memmap.phys_map         = (void *)pmap;
 462         memmap.nr_map           = e->efi_memmap_size /
 463                                   e->efi_memdesc_size;
 464         memmap.desc_size        = e->efi_memdesc_size;
 465         memmap.desc_version     = e->efi_memdesc_version;
 466
 467         memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 468
 469         return 0;
 470 }
 471
 472 #if EFI_DEBUG
 473 static void __init print_efi_memmap(void)
 474 {
 475         efi_memory_desc_t *md;
 476         void *p;
 477         int i;
 478
 479         for (p = memmap.map, i = 0;
 480              p < memmap.map_end;
 481              p += memmap.desc_size, i++) {
 482                 md = p;
 483                 pr_info("mem%02u: type=%u, attr=0x%llx, "
 484                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 485                         i, md->type, md->attribute, md->phys_addr,
 486                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 487                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 488         }
 489 }
 490 #endif  /*  EFI_DEBUG  */
 491
 492 void __init efi_reserve_boot_services(void)
 493 {
 494         void *p;
 495
 496         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 497                 efi_memory_desc_t *md = p;
 498                 u64 start = md->phys_addr;
 499                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 500
 501                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 502                     md->type != EFI_BOOT_SERVICES_DATA)
 503                         continue;
 504                 /* Only reserve where possible:
 505                  * - Not within any already allocated areas
 506                  * - Not over any memory area (really needed, if above?)
 507                  * - Not within any part of the kernel
 508                  * - Not the bios reserved area
 509                 */
 510                 if ((start+size >= __pa_symbol(_text)
 511                                 && start <= __pa_symbol(_end)) ||
 512                         !e820_all_mapped(start, start+size, E820_RAM) ||
 513                         memblock_is_region_reserved(start, size)) {
 514                         /* Could not reserve, skip it */
 515                         md->num_pages = 0;
 516                         memblock_dbg("Could not reserve boot range "
 517                                         "[0x%010llx-0x%010llx]\n",
 518                                                 start, start+size-1);
 519                 } else
 520                         memblock_reserve(start, size);
 521         }
 522 }
 523
 524 void __init efi_unmap_memmap(void)
 525 {
 526         clear_bit(EFI_MEMMAP, &x86_efi_facility);
 527         if (memmap.map) {
 528                 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 529                 memmap.map = NULL;
 530         }
 531 }
 532
 533 void __init efi_free_boot_services(void)
 534 {
 535         void *p;
 536
 537         if (!efi_is_native())
 538                 return;
 539
 540         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 541                 efi_memory_desc_t *md = p;
 542                 unsigned long long start = md->phys_addr;
 543                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 544
 545                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 546                     md->type != EFI_BOOT_SERVICES_DATA)
 547                         continue;
 548
 549                 /* Could not reserve boot area */
 550                 if (!size)
 551                         continue;
 552
 553                 free_bootmem_late(start, size);
 554         }
 555
 556         efi_unmap_memmap();
 557 }
 558
 559 static int __init efi_systab_init(void *phys)
 560 {
 561         if (efi_enabled(EFI_64BIT)) {
 562                 efi_system_table_64_t *systab64;
 563                 u64 tmp = 0;
 564
 565                 systab64 = early_ioremap((unsigned long)phys,
 566                                          sizeof(*systab64));
 567                 if (systab64 == NULL) {
 568                         pr_err("Couldn't map the system table!\n");
 569                         return -ENOMEM;
 570                 }
 571
 572                 efi_systab.hdr = systab64->hdr;
 573                 efi_systab.fw_vendor = systab64->fw_vendor;
 574                 tmp |= systab64->fw_vendor;
 575                 efi_systab.fw_revision = systab64->fw_revision;
 576                 efi_systab.con_in_handle = systab64->con_in_handle;
 577                 tmp |= systab64->con_in_handle;
 578                 efi_systab.con_in = systab64->con_in;
 579                 tmp |= systab64->con_in;
 580                 efi_systab.con_out_handle = systab64->con_out_handle;
 581                 tmp |= systab64->con_out_handle;
 582                 efi_systab.con_out = systab64->con_out;
 583                 tmp |= systab64->con_out;
 584                 efi_systab.stderr_handle = systab64->stderr_handle;
 585                 tmp |= systab64->stderr_handle;
 586                 efi_systab.stderr = systab64->stderr;
 587                 tmp |= systab64->stderr;
 588                 efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
 589                 tmp |= systab64->runtime;
 590                 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
 591                 tmp |= systab64->boottime;
 592                 efi_systab.nr_tables = systab64->nr_tables;
 593                 efi_systab.tables = systab64->tables;
 594                 tmp |= systab64->tables;
 595
 596                 early_iounmap(systab64, sizeof(*systab64));
 597 #ifdef CONFIG_X86_32
 598                 if (tmp >> 32) {
 599                         pr_err("EFI data located above 4GB, disabling EFI.\n");
 600                         return -EINVAL;
 601                 }
 602 #endif
 603         } else {
 604                 efi_system_table_32_t *systab32;
 605
 606                 systab32 = early_ioremap((unsigned long)phys,
 607                                          sizeof(*systab32));
 608                 if (systab32 == NULL) {
 609                         pr_err("Couldn't map the system table!\n");
 610                         return -ENOMEM;
 611                 }
 612
 613                 efi_systab.hdr = systab32->hdr;
 614                 efi_systab.fw_vendor = systab32->fw_vendor;
 615                 efi_systab.fw_revision = systab32->fw_revision;
 616                 efi_systab.con_in_handle = systab32->con_in_handle;
 617                 efi_systab.con_in = systab32->con_in;
 618                 efi_systab.con_out_handle = systab32->con_out_handle;
 619                 efi_systab.con_out = systab32->con_out;
 620                 efi_systab.stderr_handle = systab32->stderr_handle;
 621                 efi_systab.stderr = systab32->stderr;
 622                 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
 623                 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
 624                 efi_systab.nr_tables = systab32->nr_tables;
 625                 efi_systab.tables = systab32->tables;
 626
 627                 early_iounmap(systab32, sizeof(*systab32));
 628         }
 629
 630         efi.systab = &efi_systab;
 631
 632         /*
 633          * Verify the EFI Table
 634          */
 635         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
 636                 pr_err("System table signature incorrect!\n");
 637                 return -EINVAL;
 638         }
 639         if ((efi.systab->hdr.revision >> 16) == 0)
 640                 pr_err("Warning: System table version "
 641                        "%d.%02d, expected 1.00 or greater!\n",
 642                        efi.systab->hdr.revision >> 16,
 643                        efi.systab->hdr.revision & 0xffff);
 644
 645         return 0;
 646 }
 647
 648 static int __init efi_config_init(u64 tables, int nr_tables)
 649 {
 650         void *config_tables, *tablep;
 651         int i, sz;
 652
 653         if (efi_enabled(EFI_64BIT))
 654                 sz = sizeof(efi_config_table_64_t);
 655         else
 656                 sz = sizeof(efi_config_table_32_t);
 657
 658         /*
 659          * Let's see what config tables the firmware passed to us.
 660          */
 661         config_tables = early_ioremap(tables, nr_tables * sz);
 662         if (config_tables == NULL) {
 663                 pr_err("Could not map Configuration table!\n");
 664                 return -ENOMEM;
 665         }
 666
 667         tablep = config_tables;
 668         pr_info("");
 669         for (i = 0; i < efi.systab->nr_tables; i++) {
 670                 efi_guid_t guid;
 671                 unsigned long table;
 672
 673                 if (efi_enabled(EFI_64BIT)) {
 674                         u64 table64;
 675                         guid = ((efi_config_table_64_t *)tablep)->guid;
 676                         table64 = ((efi_config_table_64_t *)tablep)->table;
 677                         table = table64;
 678 #ifdef CONFIG_X86_32
 679                         if (table64 >> 32) {
 680                                 pr_cont("\n");
 681                                 pr_err("Table located above 4GB, disabling EFI.\n");
 682                                 early_iounmap(config_tables,
 683                                               efi.systab->nr_tables * sz);
 684                                 return -EINVAL;
 685                         }
 686 #endif
 687                 } else {
 688                         guid = ((efi_config_table_32_t *)tablep)->guid;
 689                         table = ((efi_config_table_32_t *)tablep)->table;
 690                 }
 691                 if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
 692                         efi.mps = table;
 693                         pr_cont(" MPS=0x%lx ", table);
 694                 } else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
 695                         efi.acpi20 = table;
 696                         pr_cont(" ACPI 2.0=0x%lx ", table);
 697                 } else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
 698                         efi.acpi = table;
 699                         pr_cont(" ACPI=0x%lx ", table);
 700                 } else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
 701                         efi.smbios = table;
 702                         pr_cont(" SMBIOS=0x%lx ", table);
 703 #ifdef CONFIG_X86_UV
 704                 } else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
 705                         efi.uv_systab = table;
 706                         pr_cont(" UVsystab=0x%lx ", table);
 707 #endif
 708                 } else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
 709                         efi.hcdp = table;
 710                         pr_cont(" HCDP=0x%lx ", table);
 711                 } else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
 712                         efi.uga = table;
 713                         pr_cont(" UGA=0x%lx ", table);
 714                 }
 715                 tablep += sz;
 716         }
 717         pr_cont("\n");
 718         early_iounmap(config_tables, efi.systab->nr_tables * sz);
 719         return 0;
 720 }
 721
 722 static int __init efi_runtime_init(void)
 723 {
 724         efi_runtime_services_t *runtime;
 725
 726         /*
 727          * Check out the runtime services table. We need to map
 728          * the runtime services table so that we can grab the physical
 729          * address of several of the EFI runtime functions, needed to
 730          * set the firmware into virtual mode.
 731          */
 732         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 733                                 sizeof(efi_runtime_services_t));
 734         if (!runtime) {
 735                 pr_err("Could not map the runtime service table!\n");
 736                 return -ENOMEM;
 737         }
 738         /*
 739          * We will only need *early* access to the following
 740          * two EFI runtime services before set_virtual_address_map
 741          * is invoked.
 742          */
 743         efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 744         efi_phys.set_virtual_address_map =
 745                 (efi_set_virtual_address_map_t *)
 746                 runtime->set_virtual_address_map;
 747         /*
 748          * Make efi_get_time can be called before entering
 749          * virtual mode.
 750          */
 751         efi.get_time = phys_efi_get_time;
 752         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 753
 754         return 0;
 755 }
 756
 757 static int __init efi_memmap_init(void)
 758 {
 759         /* Map the EFI memory map */
 760         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 761                                    memmap.nr_map * memmap.desc_size);
 762         if (memmap.map == NULL) {
 763                 pr_err("Could not map the memory map!\n");
 764                 return -ENOMEM;
 765         }
 766         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 767
 768         if (add_efi_memmap)
 769                 do_add_efi_memmap();
 770
 771         return 0;
 772 }
 773
 774 void __init efi_init(void)
 775 {
 776         efi_char16_t *c16;
 777         char vendor[100] = "unknown";
 778         int i = 0;
 779         void *tmp;
 780         struct setup_data *data;
 781         struct efi_var_bootdata *efi_var_data;
 782         u64 pa_data;
 783
 784 #ifdef CONFIG_X86_32
 785         if (boot_params.efi_info.efi_systab_hi ||
 786             boot_params.efi_info.efi_memmap_hi) {
 787                 pr_info("Table located above 4GB, disabling EFI.\n");
 788                 return;
 789         }
 790         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 791 #else
 792         efi_phys.systab = (efi_system_table_t *)
 793                           (boot_params.efi_info.efi_systab |
 794                           ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 795 #endif
 796
 797         if (efi_systab_init(efi_phys.systab))
 798                 return;
 799
 800         pa_data = boot_params.hdr.setup_data;
 801         while (pa_data) {
 802                 data = early_ioremap(pa_data, sizeof(*efi_var_data));
 803                 if (data->type == SETUP_EFI_VARS) {
 804                         efi_var_data = (struct efi_var_bootdata *)data;
 805
 806                         efi_var_store_size = efi_var_data->store_size;
 807                         efi_var_remaining_size = efi_var_data->remaining_size;
 808                         efi_var_max_var_size = efi_var_data->max_var_size;
 809                 }
 810                 pa_data = data->next;
 811                 early_iounmap(data, sizeof(*efi_var_data));
 812         }
 813
 814         boot_used_size = efi_var_store_size - efi_var_remaining_size;
 815
 816         set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
 817
 818         /*
 819          * Show what we know for posterity
 820          */
 821         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 822         if (c16) {
 823                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 824                         vendor[i] = *c16++;
 825                 vendor[i] = '\0';
 826         } else
 827                 pr_err("Could not map the firmware vendor!\n");
 828         early_iounmap(tmp, 2);
 829
 830         pr_info("EFI v%u.%.02u by %s\n",
 831                 efi.systab->hdr.revision >> 16,
 832                 efi.systab->hdr.revision & 0xffff, vendor);
 833
 834         if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
 835                 return;
 836
 837         set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
 838
 839         /*
 840          * Note: We currently don't support runtime services on an EFI
 841          * that doesn't match the kernel 32/64-bit mode.
 842          */
 843
 844         if (!efi_is_native())
 845                 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 846         else {
 847                 if (disable_runtime || efi_runtime_init())
 848                         return;
 849                 set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
 850         }
 851
 852         if (efi_memmap_init())
 853                 return;
 854
 855         set_bit(EFI_MEMMAP, &x86_efi_facility);
 856
 857 #ifdef CONFIG_X86_32
 858         if (efi_is_native()) {
 859                 x86_platform.get_wallclock = efi_get_time;
 860                 x86_platform.set_wallclock = efi_set_rtc_mmss;
 861         }
 862 #endif
 863
 864 #if EFI_DEBUG
 865         print_efi_memmap();
 866 #endif
 867 }
 868
 869 void __init efi_late_init(void)
 870 {
 871         efi_bgrt_init();
 872 }
 873
 874 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 875 {
 876         u64 addr, npages;
 877
 878         addr = md->virt_addr;
 879         npages = md->num_pages;
 880
 881         memrange_efi_to_native(&addr, &npages);
 882
 883         if (executable)
 884                 set_memory_x(addr, npages);
 885         else
 886                 set_memory_nx(addr, npages);
 887 }
 888
 889 static void __init runtime_code_page_mkexec(void)
 890 {
 891         efi_memory_desc_t *md;
 892         void *p;
 893
 894         /* Make EFI runtime service code area executable */
 895         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 896                 md = p;
 897
 898                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 899                         continue;
 900
 901                 efi_set_executable(md, true);
 902         }
 903 }
 904
 905 /*
 906  * We can't ioremap data in EFI boot services RAM, because we've already mapped
 907  * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
 908  * callable after efi_enter_virtual_mode and before efi_free_boot_services.
 909  */
 910 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
 911 {
 912         void *p;
 913         if (WARN_ON(!memmap.map))
 914                 return NULL;
 915         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 916                 efi_memory_desc_t *md = p;
 917                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 918                 u64 end = md->phys_addr + size;
 919                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 920                     md->type != EFI_BOOT_SERVICES_CODE &&
 921                     md->type != EFI_BOOT_SERVICES_DATA)
 922                         continue;
 923                 if (!md->virt_addr)
 924                         continue;
 925                 if (phys_addr >= md->phys_addr && phys_addr < end) {
 926                         phys_addr += md->virt_addr - md->phys_addr;
 927                         return (__force void __iomem *)(unsigned long)phys_addr;
 928                 }
 929         }
 930         return NULL;
 931 }
 932
 933 void efi_memory_uc(u64 addr, unsigned long size)
 934 {
 935         unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
 936         u64 npages;
 937
 938         npages = round_up(size, page_shift) / page_shift;
 939         memrange_efi_to_native(&addr, &npages);
 940         set_memory_uc(addr, npages);
 941 }
 942
 943 /*
 944  * This function will switch the EFI runtime services to virtual mode.
 945  * Essentially, look through the EFI memmap and map every region that
 946  * has the runtime attribute bit set in its memory descriptor and update
 947  * that memory descriptor with the virtual address obtained from ioremap().
 948  * This enables the runtime services to be called without having to
 949  * thunk back into physical mode for every invocation.
 950  */
 951 void __init efi_enter_virtual_mode(void)
 952 {
 953         efi_memory_desc_t *md, *prev_md = NULL;
 954         efi_status_t status;
 955         unsigned long size;
 956         u64 end, systab, start_pfn, end_pfn;
 957         void *p, *va, *new_memmap = NULL;
 958         int count = 0;
 959
 960         efi.systab = NULL;
 961
 962         /*
 963          * We don't do virtual mode, since we don't do runtime services, on
 964          * non-native EFI
 965          */
 966
 967         if (!efi_is_native()) {
 968                 efi_unmap_memmap();
 969                 return;
 970         }
 971
 972         /* Merge contiguous regions of the same type and attribute */
 973         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 974                 u64 prev_size;
 975                 md = p;
 976
 977                 if (!prev_md) {
 978                         prev_md = md;
 979                         continue;
 980                 }
 981
 982                 if (prev_md->type != md->type ||
 983                     prev_md->attribute != md->attribute) {
 984                         prev_md = md;
 985                         continue;
 986                 }
 987
 988                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 989
 990                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 991                         prev_md->num_pages += md->num_pages;
 992                         md->type = EFI_RESERVED_TYPE;
 993                         md->attribute = 0;
 994                         continue;
 995                 }
 996                 prev_md = md;
 997         }
 998
 999         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1000                 md = p;
1001                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
1002                     md->type != EFI_BOOT_SERVICES_CODE &&
1003                     md->type != EFI_BOOT_SERVICES_DATA)
1004                         continue;
1005
1006                 size = md->num_pages << EFI_PAGE_SHIFT;
1007                 end = md->phys_addr + size;
1008
1009                 start_pfn = PFN_DOWN(md->phys_addr);
1010                 end_pfn = PFN_UP(end);
1011                 if (pfn_range_is_mapped(start_pfn, end_pfn)) {
1012                         va = __va(md->phys_addr);
1013
1014                         if (!(md->attribute & EFI_MEMORY_WB))
1015                                 efi_memory_uc((u64)(unsigned long)va, size);
1016                 } else
1017                         va = efi_ioremap(md->phys_addr, size,
1018                                          md->type, md->attribute);
1019
1020                 md->virt_addr = (u64) (unsigned long) va;
1021
1022                 if (!va) {
1023                         pr_err("ioremap of 0x%llX failed!\n",
1024                                (unsigned long long)md->phys_addr);
1025                         continue;
1026                 }
1027
1028                 systab = (u64) (unsigned long) efi_phys.systab;
1029                 if (md->phys_addr <= systab && systab < end) {
1030                         systab += md->virt_addr - md->phys_addr;
1031                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
1032                 }
1033                 new_memmap = krealloc(new_memmap,
1034                                       (count + 1) * memmap.desc_size,
1035                                       GFP_KERNEL);
1036                 memcpy(new_memmap + (count * memmap.desc_size), md,
1037                        memmap.desc_size);
1038                 count++;
1039         }
1040
1041         BUG_ON(!efi.systab);
1042
1043         status = phys_efi_set_virtual_address_map(
1044                 memmap.desc_size * count,
1045                 memmap.desc_size,
1046                 memmap.desc_version,
1047                 (efi_memory_desc_t *)__pa(new_memmap));
1048
1049         if (status != EFI_SUCCESS) {
1050                 pr_alert("Unable to switch EFI into virtual mode "
1051                          "(status=%lx)!\n", status);
1052                 panic("EFI call to SetVirtualAddressMap() failed!");
1053         }
1054
1055         /*
1056          * Now that EFI is in virtual mode, update the function
1057          * pointers in the runtime service table to the new virtual addresses.
1058          *
1059          * Call EFI services through wrapper functions.
1060          */
1061         efi.runtime_version = efi_systab.hdr.revision;
1062         efi.get_time = virt_efi_get_time;
1063         efi.set_time = virt_efi_set_time;
1064         efi.get_wakeup_time = virt_efi_get_wakeup_time;
1065         efi.set_wakeup_time = virt_efi_set_wakeup_time;
1066         efi.get_variable = virt_efi_get_variable;
1067         efi.get_next_variable = virt_efi_get_next_variable;
1068         efi.set_variable = virt_efi_set_variable;
1069         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
1070         efi.reset_system = virt_efi_reset_system;
1071         efi.set_virtual_address_map = NULL;
1072         efi.query_variable_info = virt_efi_query_variable_info;
1073         efi.update_capsule = virt_efi_update_capsule;
1074         efi.query_capsule_caps = virt_efi_query_capsule_caps;
1075         if (__supported_pte_mask & _PAGE_NX)
1076                 runtime_code_page_mkexec();
1077
1078         kfree(new_memmap);
1079 }
1080
1081 /*
1082  * Convenience functions to obtain memory types and attributes
1083  */
1084 u32 efi_mem_type(unsigned long phys_addr)
1085 {
1086         efi_memory_desc_t *md;
1087         void *p;
1088
1089         if (!efi_enabled(EFI_MEMMAP))
1090                 return 0;
1091
1092         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1093                 md = p;
1094                 if ((md->phys_addr <= phys_addr) &&
1095                     (phys_addr < (md->phys_addr +
1096                                   (md->num_pages << EFI_PAGE_SHIFT))))
1097                         return md->type;
1098         }
1099         return 0;
1100 }
1101
1102 u64 efi_mem_attributes(unsigned long phys_addr)
1103 {
1104         efi_memory_desc_t *md;
1105         void *p;
1106
1107         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1108                 md = p;
1109                 if ((md->phys_addr <= phys_addr) &&
1110                     (phys_addr < (md->phys_addr +
1111                                   (md->num_pages << EFI_PAGE_SHIFT))))
1112                         return md->attribute;
1113         }
1114         return 0;
1115 }
1116
1117 /*
1118  * Some firmware has serious problems when using more than 50% of the EFI
1119  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
1120  * we never use more than this safe limit.
1121  *
1122  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
1123  * store.
1124  */
1125 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
1126 {
1127         efi_status_t status;
1128         u64 storage_size, remaining_size, max_size;
1129
1130         status = efi.query_variable_info(attributes, &storage_size,
1131                                          &remaining_size, &max_size);
1132         if (status != EFI_SUCCESS)
1133                 return status;
1134
1135         if (!max_size && remaining_size > size)
1136                 printk_once(KERN_ERR FW_BUG "Broken EFI implementation"
1137                             " is returning MaxVariableSize=0\n");
1138         /*
1139          * Some firmware implementations refuse to boot if there's insufficient
1140          * space in the variable store. We account for that by refusing the
1141          * write if permitting it would reduce the available space to under
1142          * 50%. However, some firmware won't reclaim variable space until
1143          * after the used (not merely the actively used) space drops below
1144          * a threshold. We can approximate that case with the value calculated
1145          * above. If both the firmware and our calculations indicate that the
1146          * available space would drop below 50%, refuse the write.
1147          */
1148
1149         if (!storage_size || size > remaining_size ||
1150             (max_size && size > max_size))
1151                 return EFI_OUT_OF_RESOURCES;
1152
1153         if (!efi_no_storage_paranoia &&
1154             ((active_size + size + VAR_METADATA_SIZE > storage_size / 2) &&
1155              (remaining_size - size < storage_size / 2)))
1156                 return EFI_OUT_OF_RESOURCES;
1157
1158         return EFI_SUCCESS;
1159 }
1160 EXPORT_SYMBOL_GPL(efi_query_variable_store);