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 #include <asm/rtc.h>
  53
  54 #define EFI_DEBUG       1
  55
  56 /*
  57  * There's some additional metadata associated with each
  58  * variable. Intel's reference implementation is 60 bytes - bump that
  59  * to account for potential alignment constraints
  60  */
  61 #define VAR_METADATA_SIZE 64
  62
  63 struct efi __read_mostly efi = {
  64         .mps        = EFI_INVALID_TABLE_ADDR,
  65         .acpi       = EFI_INVALID_TABLE_ADDR,
  66         .acpi20     = EFI_INVALID_TABLE_ADDR,
  67         .smbios     = EFI_INVALID_TABLE_ADDR,
  68         .sal_systab = EFI_INVALID_TABLE_ADDR,
  69         .boot_info  = EFI_INVALID_TABLE_ADDR,
  70         .hcdp       = EFI_INVALID_TABLE_ADDR,
  71         .uga        = EFI_INVALID_TABLE_ADDR,
  72         .uv_systab  = EFI_INVALID_TABLE_ADDR,
  73 };
  74 EXPORT_SYMBOL(efi);
  75
  76 struct efi_memory_map memmap;
  77
  78 static struct efi efi_phys __initdata;
  79 static efi_system_table_t efi_systab __initdata;
  80
  81 static u64 efi_var_store_size;
  82 static u64 efi_var_remaining_size;
  83 static u64 efi_var_max_var_size;
  84 static u64 boot_used_size;
  85 static u64 boot_var_size;
  86 static u64 active_size;
  87
  88 unsigned long x86_efi_facility;
  89
  90 /*
  91  * Returns 1 if 'facility' is enabled, 0 otherwise.
  92  */
  93 int efi_enabled(int facility)
  94 {
  95         return test_bit(facility, &x86_efi_facility) != 0;
  96 }
  97 EXPORT_SYMBOL(efi_enabled);
  98
  99 static bool __initdata disable_runtime = false;
 100 static int __init setup_noefi(char *arg)
 101 {
 102         disable_runtime = true;
 103         return 0;
 104 }
 105 early_param("noefi", setup_noefi);
 106
 107 int add_efi_memmap;
 108 EXPORT_SYMBOL(add_efi_memmap);
 109
 110 static int __init setup_add_efi_memmap(char *arg)
 111 {
 112         add_efi_memmap = 1;
 113         return 0;
 114 }
 115 early_param("add_efi_memmap", setup_add_efi_memmap);
 116
 117 static bool efi_no_storage_paranoia;
 118
 119 static int __init setup_storage_paranoia(char *arg)
 120 {
 121         efi_no_storage_paranoia = true;
 122         return 0;
 123 }
 124 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
 125
 126
 127 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 128 {
 129         unsigned long flags;
 130         efi_status_t status;
 131
 132         spin_lock_irqsave(&rtc_lock, flags);
 133         status = efi_call_virt2(get_time, tm, tc);
 134         spin_unlock_irqrestore(&rtc_lock, flags);
 135         return status;
 136 }
 137
 138 static efi_status_t virt_efi_set_time(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_virt1(set_time, tm);
 145         spin_unlock_irqrestore(&rtc_lock, flags);
 146         return status;
 147 }
 148
 149 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
 150                                              efi_bool_t *pending,
 151                                              efi_time_t *tm)
 152 {
 153         unsigned long flags;
 154         efi_status_t status;
 155
 156         spin_lock_irqsave(&rtc_lock, flags);
 157         status = efi_call_virt3(get_wakeup_time,
 158                                 enabled, pending, tm);
 159         spin_unlock_irqrestore(&rtc_lock, flags);
 160         return status;
 161 }
 162
 163 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
 164 {
 165         unsigned long flags;
 166         efi_status_t status;
 167
 168         spin_lock_irqsave(&rtc_lock, flags);
 169         status = efi_call_virt2(set_wakeup_time,
 170                                 enabled, tm);
 171         spin_unlock_irqrestore(&rtc_lock, flags);
 172         return status;
 173 }
 174
 175 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
 176                                           efi_guid_t *vendor,
 177                                           u32 *attr,
 178                                           unsigned long *data_size,
 179                                           void *data)
 180 {
 181         return efi_call_virt5(get_variable,
 182                               name, vendor, attr,
 183                               data_size, data);
 184 }
 185
 186 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 187                                                efi_char16_t *name,
 188                                                efi_guid_t *vendor)
 189 {
 190         efi_status_t status;
 191         static bool finished = false;
 192         static u64 var_size;
 193
 194         status = efi_call_virt3(get_next_variable,
 195                                 name_size, name, vendor);
 196
 197         if (status == EFI_NOT_FOUND) {
 198                 finished = true;
 199                 if (var_size < boot_used_size) {
 200                         boot_var_size = boot_used_size - var_size;
 201                         active_size += boot_var_size;
 202                 } else {
 203                         printk(KERN_WARNING FW_BUG  "efi: Inconsistent initial sizes\n");
 204                 }
 205         }
 206
 207         if (boot_used_size && !finished) {
 208                 unsigned long size;
 209                 u32 attr;
 210                 efi_status_t s;
 211                 void *tmp;
 212
 213                 s = virt_efi_get_variable(name, vendor, &attr, &size, NULL);
 214
 215                 if (s != EFI_BUFFER_TOO_SMALL || !size)
 216                         return status;
 217
 218                 tmp = kmalloc(size, GFP_ATOMIC);
 219
 220                 if (!tmp)
 221                         return status;
 222
 223                 s = virt_efi_get_variable(name, vendor, &attr, &size, tmp);
 224
 225                 if (s == EFI_SUCCESS && (attr & EFI_VARIABLE_NON_VOLATILE)) {
 226                         var_size += size;
 227                         var_size += ucs2_strsize(name, 1024);
 228                         active_size += size;
 229                         active_size += VAR_METADATA_SIZE;
 230                         active_size += ucs2_strsize(name, 1024);
 231                 }
 232
 233                 kfree(tmp);
 234         }
 235
 236         return status;
 237 }
 238
 239 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 240                                           efi_guid_t *vendor,
 241                                           u32 attr,
 242                                           unsigned long data_size,
 243                                           void *data)
 244 {
 245         efi_status_t status;
 246         u32 orig_attr = 0;
 247         unsigned long orig_size = 0;
 248
 249         status = virt_efi_get_variable(name, vendor, &orig_attr, &orig_size,
 250                                        NULL);
 251
 252         if (status != EFI_BUFFER_TOO_SMALL)
 253                 orig_size = 0;
 254
 255         status = efi_call_virt5(set_variable,
 256                                 name, vendor, attr,
 257                                 data_size, data);
 258
 259         if (status == EFI_SUCCESS) {
 260                 if (orig_size) {
 261                         active_size -= orig_size;
 262                         active_size -= ucs2_strsize(name, 1024);
 263                         active_size -= VAR_METADATA_SIZE;
 264                 }
 265                 if (data_size) {
 266                         active_size += data_size;
 267                         active_size += ucs2_strsize(name, 1024);
 268                         active_size += VAR_METADATA_SIZE;
 269                 }
 270         }
 271
 272         return status;
 273 }
 274
 275 static efi_status_t virt_efi_query_variable_info(u32 attr,
 276                                                  u64 *storage_space,
 277                                                  u64 *remaining_space,
 278                                                  u64 *max_variable_size)
 279 {
 280         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 281                 return EFI_UNSUPPORTED;
 282
 283         return efi_call_virt4(query_variable_info, attr, storage_space,
 284                               remaining_space, max_variable_size);
 285 }
 286
 287 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 288 {
 289         return efi_call_virt1(get_next_high_mono_count, count);
 290 }
 291
 292 static void virt_efi_reset_system(int reset_type,
 293                                   efi_status_t status,
 294                                   unsigned long data_size,
 295                                   efi_char16_t *data)
 296 {
 297         efi_call_virt4(reset_system, reset_type, status,
 298                        data_size, data);
 299 }
 300
 301 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
 302                                             unsigned long count,
 303                                             unsigned long sg_list)
 304 {
 305         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 306                 return EFI_UNSUPPORTED;
 307
 308         return efi_call_virt3(update_capsule, capsules, count, sg_list);
 309 }
 310
 311 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
 312                                                 unsigned long count,
 313                                                 u64 *max_size,
 314                                                 int *reset_type)
 315 {
 316         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 317                 return EFI_UNSUPPORTED;
 318
 319         return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
 320                               reset_type);
 321 }
 322
 323 static efi_status_t __init phys_efi_set_virtual_address_map(
 324         unsigned long memory_map_size,
 325         unsigned long descriptor_size,
 326         u32 descriptor_version,
 327         efi_memory_desc_t *virtual_map)
 328 {
 329         efi_status_t status;
 330
 331         efi_call_phys_prelog();
 332         status = efi_call_phys4(efi_phys.set_virtual_address_map,
 333                                 memory_map_size, descriptor_size,
 334                                 descriptor_version, virtual_map);
 335         efi_call_phys_epilog();
 336         return status;
 337 }
 338
 339 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
 340                                              efi_time_cap_t *tc)
 341 {
 342         unsigned long flags;
 343         efi_status_t status;
 344
 345         spin_lock_irqsave(&rtc_lock, flags);
 346         efi_call_phys_prelog();
 347         status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
 348                                 virt_to_phys(tc));
 349         efi_call_phys_epilog();
 350         spin_unlock_irqrestore(&rtc_lock, flags);
 351         return status;
 352 }
 353
 354 int efi_set_rtc_mmss(unsigned long nowtime)
 355 {
 356         efi_status_t    status;
 357         efi_time_t      eft;
 358         efi_time_cap_t  cap;
 359         struct rtc_time tm;
 360
 361         status = efi.get_time(&eft, &cap);
 362         if (status != EFI_SUCCESS) {
 363                 pr_err("Oops: efitime: can't read time!\n");
 364                 return -1;
 365         }
 366
 367         rtc_time_to_tm(nowtime, &tm);
 368         if (!rtc_valid_tm(&tm)) {
 369                 eft.year = tm.tm_year + 1900;
 370                 eft.month = tm.tm_mon + 1;
 371                 eft.day = tm.tm_mday;
 372                 eft.minute = tm.tm_min;
 373                 eft.second = tm.tm_sec;
 374                 eft.nanosecond = 0;
 375         } else {
 376                 printk(KERN_ERR
 377                        "%s: Invalid EFI RTC value: write of %lx to EFI RTC failed\n",
 378                        __FUNCTION__, nowtime);
 379                 return -1;
 380         }
 381
 382         status = efi.set_time(&eft);
 383         if (status != EFI_SUCCESS) {
 384                 pr_err("Oops: efitime: can't write time!\n");
 385                 return -1;
 386         }
 387         return 0;
 388 }
 389
 390 unsigned long efi_get_time(void)
 391 {
 392         efi_status_t status;
 393         efi_time_t eft;
 394         efi_time_cap_t cap;
 395
 396         status = efi.get_time(&eft, &cap);
 397         if (status != EFI_SUCCESS)
 398                 pr_err("Oops: efitime: can't read time!\n");
 399
 400         return mktime(eft.year, eft.month, eft.day, eft.hour,
 401                       eft.minute, eft.second);
 402 }
 403
 404 /*
 405  * Tell the kernel about the EFI memory map.  This might include
 406  * more than the max 128 entries that can fit in the e820 legacy
 407  * (zeropage) memory map.
 408  */
 409
 410 static void __init do_add_efi_memmap(void)
 411 {
 412         void *p;
 413
 414         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 415                 efi_memory_desc_t *md = p;
 416                 unsigned long long start = md->phys_addr;
 417                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 418                 int e820_type;
 419
 420                 switch (md->type) {
 421                 case EFI_LOADER_CODE:
 422                 case EFI_LOADER_DATA:
 423                 case EFI_BOOT_SERVICES_CODE:
 424                 case EFI_BOOT_SERVICES_DATA:
 425                 case EFI_CONVENTIONAL_MEMORY:
 426                         if (md->attribute & EFI_MEMORY_WB)
 427                                 e820_type = E820_RAM;
 428                         else
 429                                 e820_type = E820_RESERVED;
 430                         break;
 431                 case EFI_ACPI_RECLAIM_MEMORY:
 432                         e820_type = E820_ACPI;
 433                         break;
 434                 case EFI_ACPI_MEMORY_NVS:
 435                         e820_type = E820_NVS;
 436                         break;
 437                 case EFI_UNUSABLE_MEMORY:
 438                         e820_type = E820_UNUSABLE;
 439                         break;
 440                 default:
 441                         /*
 442                          * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 443                          * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 444                          * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 445                          */
 446                         e820_type = E820_RESERVED;
 447                         break;
 448                 }
 449                 e820_add_region(start, size, e820_type);
 450         }
 451         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 452 }
 453
 454 int __init efi_memblock_x86_reserve_range(void)
 455 {
 456         struct efi_info *e = &boot_params.efi_info;
 457         unsigned long pmap;
 458
 459 #ifdef CONFIG_X86_32
 460         /* Can't handle data above 4GB at this time */
 461         if (e->efi_memmap_hi) {
 462                 pr_err("Memory map is above 4GB, disabling EFI.\n");
 463                 return -EINVAL;
 464         }
 465         pmap =  e->efi_memmap;
 466 #else
 467         pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
 468 #endif
 469         memmap.phys_map         = (void *)pmap;
 470         memmap.nr_map           = e->efi_memmap_size /
 471                                   e->efi_memdesc_size;
 472         memmap.desc_size        = e->efi_memdesc_size;
 473         memmap.desc_version     = e->efi_memdesc_version;
 474
 475         memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 476
 477         return 0;
 478 }
 479
 480 #if EFI_DEBUG
 481 static void __init print_efi_memmap(void)
 482 {
 483         efi_memory_desc_t *md;
 484         void *p;
 485         int i;
 486
 487         for (p = memmap.map, i = 0;
 488              p < memmap.map_end;
 489              p += memmap.desc_size, i++) {
 490                 md = p;
 491                 pr_info("mem%02u: type=%u, attr=0x%llx, "
 492                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 493                         i, md->type, md->attribute, md->phys_addr,
 494                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 495                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 496         }
 497 }
 498 #endif  /*  EFI_DEBUG  */
 499
 500 void __init efi_reserve_boot_services(void)
 501 {
 502         void *p;
 503
 504         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 505                 efi_memory_desc_t *md = p;
 506                 u64 start = md->phys_addr;
 507                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 508
 509                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 510                     md->type != EFI_BOOT_SERVICES_DATA)
 511                         continue;
 512                 /* Only reserve where possible:
 513                  * - Not within any already allocated areas
 514                  * - Not over any memory area (really needed, if above?)
 515                  * - Not within any part of the kernel
 516                  * - Not the bios reserved area
 517                 */
 518                 if ((start+size >= __pa_symbol(_text)
 519                                 && start <= __pa_symbol(_end)) ||
 520                         !e820_all_mapped(start, start+size, E820_RAM) ||
 521                         memblock_is_region_reserved(start, size)) {
 522                         /* Could not reserve, skip it */
 523                         md->num_pages = 0;
 524                         memblock_dbg("Could not reserve boot range "
 525                                         "[0x%010llx-0x%010llx]\n",
 526                                                 start, start+size-1);
 527                 } else
 528                         memblock_reserve(start, size);
 529         }
 530 }
 531
 532 void __init efi_unmap_memmap(void)
 533 {
 534         clear_bit(EFI_MEMMAP, &x86_efi_facility);
 535         if (memmap.map) {
 536                 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 537                 memmap.map = NULL;
 538         }
 539 }
 540
 541 void __init efi_free_boot_services(void)
 542 {
 543         void *p;
 544
 545         if (!efi_is_native())
 546                 return;
 547
 548         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 549                 efi_memory_desc_t *md = p;
 550                 unsigned long long start = md->phys_addr;
 551                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 552
 553                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 554                     md->type != EFI_BOOT_SERVICES_DATA)
 555                         continue;
 556
 557                 /* Could not reserve boot area */
 558                 if (!size)
 559                         continue;
 560
 561                 free_bootmem_late(start, size);
 562         }
 563
 564         efi_unmap_memmap();
 565 }
 566
 567 static int __init efi_systab_init(void *phys)
 568 {
 569         if (efi_enabled(EFI_64BIT)) {
 570                 efi_system_table_64_t *systab64;
 571                 u64 tmp = 0;
 572
 573                 systab64 = early_ioremap((unsigned long)phys,
 574                                          sizeof(*systab64));
 575                 if (systab64 == NULL) {
 576                         pr_err("Couldn't map the system table!\n");
 577                         return -ENOMEM;
 578                 }
 579
 580                 efi_systab.hdr = systab64->hdr;
 581                 efi_systab.fw_vendor = systab64->fw_vendor;
 582                 tmp |= systab64->fw_vendor;
 583                 efi_systab.fw_revision = systab64->fw_revision;
 584                 efi_systab.con_in_handle = systab64->con_in_handle;
 585                 tmp |= systab64->con_in_handle;
 586                 efi_systab.con_in = systab64->con_in;
 587                 tmp |= systab64->con_in;
 588                 efi_systab.con_out_handle = systab64->con_out_handle;
 589                 tmp |= systab64->con_out_handle;
 590                 efi_systab.con_out = systab64->con_out;
 591                 tmp |= systab64->con_out;
 592                 efi_systab.stderr_handle = systab64->stderr_handle;
 593                 tmp |= systab64->stderr_handle;
 594                 efi_systab.stderr = systab64->stderr;
 595                 tmp |= systab64->stderr;
 596                 efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
 597                 tmp |= systab64->runtime;
 598                 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
 599                 tmp |= systab64->boottime;
 600                 efi_systab.nr_tables = systab64->nr_tables;
 601                 efi_systab.tables = systab64->tables;
 602                 tmp |= systab64->tables;
 603
 604                 early_iounmap(systab64, sizeof(*systab64));
 605 #ifdef CONFIG_X86_32
 606                 if (tmp >> 32) {
 607                         pr_err("EFI data located above 4GB, disabling EFI.\n");
 608                         return -EINVAL;
 609                 }
 610 #endif
 611         } else {
 612                 efi_system_table_32_t *systab32;
 613
 614                 systab32 = early_ioremap((unsigned long)phys,
 615                                          sizeof(*systab32));
 616                 if (systab32 == NULL) {
 617                         pr_err("Couldn't map the system table!\n");
 618                         return -ENOMEM;
 619                 }
 620
 621                 efi_systab.hdr = systab32->hdr;
 622                 efi_systab.fw_vendor = systab32->fw_vendor;
 623                 efi_systab.fw_revision = systab32->fw_revision;
 624                 efi_systab.con_in_handle = systab32->con_in_handle;
 625                 efi_systab.con_in = systab32->con_in;
 626                 efi_systab.con_out_handle = systab32->con_out_handle;
 627                 efi_systab.con_out = systab32->con_out;
 628                 efi_systab.stderr_handle = systab32->stderr_handle;
 629                 efi_systab.stderr = systab32->stderr;
 630                 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
 631                 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
 632                 efi_systab.nr_tables = systab32->nr_tables;
 633                 efi_systab.tables = systab32->tables;
 634
 635                 early_iounmap(systab32, sizeof(*systab32));
 636         }
 637
 638         efi.systab = &efi_systab;
 639
 640         /*
 641          * Verify the EFI Table
 642          */
 643         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
 644                 pr_err("System table signature incorrect!\n");
 645                 return -EINVAL;
 646         }
 647         if ((efi.systab->hdr.revision >> 16) == 0)
 648                 pr_err("Warning: System table version "
 649                        "%d.%02d, expected 1.00 or greater!\n",
 650                        efi.systab->hdr.revision >> 16,
 651                        efi.systab->hdr.revision & 0xffff);
 652
 653         return 0;
 654 }
 655
 656 static int __init efi_config_init(u64 tables, int nr_tables)
 657 {
 658         void *config_tables, *tablep;
 659         int i, sz;
 660
 661         if (efi_enabled(EFI_64BIT))
 662                 sz = sizeof(efi_config_table_64_t);
 663         else
 664                 sz = sizeof(efi_config_table_32_t);
 665
 666         /*
 667          * Let's see what config tables the firmware passed to us.
 668          */
 669         config_tables = early_ioremap(tables, nr_tables * sz);
 670         if (config_tables == NULL) {
 671                 pr_err("Could not map Configuration table!\n");
 672                 return -ENOMEM;
 673         }
 674
 675         tablep = config_tables;
 676         pr_info("");
 677         for (i = 0; i < efi.systab->nr_tables; i++) {
 678                 efi_guid_t guid;
 679                 unsigned long table;
 680
 681                 if (efi_enabled(EFI_64BIT)) {
 682                         u64 table64;
 683                         guid = ((efi_config_table_64_t *)tablep)->guid;
 684                         table64 = ((efi_config_table_64_t *)tablep)->table;
 685                         table = table64;
 686 #ifdef CONFIG_X86_32
 687                         if (table64 >> 32) {
 688                                 pr_cont("\n");
 689                                 pr_err("Table located above 4GB, disabling EFI.\n");
 690                                 early_iounmap(config_tables,
 691                                               efi.systab->nr_tables * sz);
 692                                 return -EINVAL;
 693                         }
 694 #endif
 695                 } else {
 696                         guid = ((efi_config_table_32_t *)tablep)->guid;
 697                         table = ((efi_config_table_32_t *)tablep)->table;
 698                 }
 699                 if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
 700                         efi.mps = table;
 701                         pr_cont(" MPS=0x%lx ", table);
 702                 } else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
 703                         efi.acpi20 = table;
 704                         pr_cont(" ACPI 2.0=0x%lx ", table);
 705                 } else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
 706                         efi.acpi = table;
 707                         pr_cont(" ACPI=0x%lx ", table);
 708                 } else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
 709                         efi.smbios = table;
 710                         pr_cont(" SMBIOS=0x%lx ", table);
 711 #ifdef CONFIG_X86_UV
 712                 } else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
 713                         efi.uv_systab = table;
 714                         pr_cont(" UVsystab=0x%lx ", table);
 715 #endif
 716                 } else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
 717                         efi.hcdp = table;
 718                         pr_cont(" HCDP=0x%lx ", table);
 719                 } else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
 720                         efi.uga = table;
 721                         pr_cont(" UGA=0x%lx ", table);
 722                 }
 723                 tablep += sz;
 724         }
 725         pr_cont("\n");
 726         early_iounmap(config_tables, efi.systab->nr_tables * sz);
 727         return 0;
 728 }
 729
 730 static int __init efi_runtime_init(void)
 731 {
 732         efi_runtime_services_t *runtime;
 733
 734         /*
 735          * Check out the runtime services table. We need to map
 736          * the runtime services table so that we can grab the physical
 737          * address of several of the EFI runtime functions, needed to
 738          * set the firmware into virtual mode.
 739          */
 740         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 741                                 sizeof(efi_runtime_services_t));
 742         if (!runtime) {
 743                 pr_err("Could not map the runtime service table!\n");
 744                 return -ENOMEM;
 745         }
 746         /*
 747          * We will only need *early* access to the following
 748          * two EFI runtime services before set_virtual_address_map
 749          * is invoked.
 750          */
 751         efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 752         efi_phys.set_virtual_address_map =
 753                 (efi_set_virtual_address_map_t *)
 754                 runtime->set_virtual_address_map;
 755         /*
 756          * Make efi_get_time can be called before entering
 757          * virtual mode.
 758          */
 759         efi.get_time = phys_efi_get_time;
 760         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 761
 762         return 0;
 763 }
 764
 765 static int __init efi_memmap_init(void)
 766 {
 767         /* Map the EFI memory map */
 768         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 769                                    memmap.nr_map * memmap.desc_size);
 770         if (memmap.map == NULL) {
 771                 pr_err("Could not map the memory map!\n");
 772                 return -ENOMEM;
 773         }
 774         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 775
 776         if (add_efi_memmap)
 777                 do_add_efi_memmap();
 778
 779         return 0;
 780 }
 781
 782 void __init efi_init(void)
 783 {
 784         efi_char16_t *c16;
 785         char vendor[100] = "unknown";
 786         int i = 0;
 787         void *tmp;
 788         struct setup_data *data;
 789         struct efi_var_bootdata *efi_var_data;
 790         u64 pa_data;
 791
 792 #ifdef CONFIG_X86_32
 793         if (boot_params.efi_info.efi_systab_hi ||
 794             boot_params.efi_info.efi_memmap_hi) {
 795                 pr_info("Table located above 4GB, disabling EFI.\n");
 796                 return;
 797         }
 798         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 799 #else
 800         efi_phys.systab = (efi_system_table_t *)
 801                           (boot_params.efi_info.efi_systab |
 802                           ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 803 #endif
 804
 805         if (efi_systab_init(efi_phys.systab))
 806                 return;
 807
 808         pa_data = boot_params.hdr.setup_data;
 809         while (pa_data) {
 810                 data = early_ioremap(pa_data, sizeof(*efi_var_data));
 811                 if (data->type == SETUP_EFI_VARS) {
 812                         efi_var_data = (struct efi_var_bootdata *)data;
 813
 814                         efi_var_store_size = efi_var_data->store_size;
 815                         efi_var_remaining_size = efi_var_data->remaining_size;
 816                         efi_var_max_var_size = efi_var_data->max_var_size;
 817                 }
 818                 pa_data = data->next;
 819                 early_iounmap(data, sizeof(*efi_var_data));
 820         }
 821
 822         boot_used_size = efi_var_store_size - efi_var_remaining_size;
 823
 824         set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
 825
 826         /*
 827          * Show what we know for posterity
 828          */
 829         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 830         if (c16) {
 831                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 832                         vendor[i] = *c16++;
 833                 vendor[i] = '\0';
 834         } else
 835                 pr_err("Could not map the firmware vendor!\n");
 836         early_iounmap(tmp, 2);
 837
 838         pr_info("EFI v%u.%.02u by %s\n",
 839                 efi.systab->hdr.revision >> 16,
 840                 efi.systab->hdr.revision & 0xffff, vendor);
 841
 842         if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
 843                 return;
 844
 845         set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
 846
 847         /*
 848          * Note: We currently don't support runtime services on an EFI
 849          * that doesn't match the kernel 32/64-bit mode.
 850          */
 851
 852         if (!efi_is_native())
 853                 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 854         else {
 855                 if (disable_runtime || efi_runtime_init())
 856                         return;
 857                 set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
 858         }
 859
 860         if (efi_memmap_init())
 861                 return;
 862
 863         set_bit(EFI_MEMMAP, &x86_efi_facility);
 864
 865 #ifdef CONFIG_X86_32
 866         if (efi_is_native()) {
 867                 x86_platform.get_wallclock = efi_get_time;
 868                 x86_platform.set_wallclock = efi_set_rtc_mmss;
 869         }
 870 #endif
 871
 872 #if EFI_DEBUG
 873         print_efi_memmap();
 874 #endif
 875 }
 876
 877 void __init efi_late_init(void)
 878 {
 879         efi_bgrt_init();
 880 }
 881
 882 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 883 {
 884         u64 addr, npages;
 885
 886         addr = md->virt_addr;
 887         npages = md->num_pages;
 888
 889         memrange_efi_to_native(&addr, &npages);
 890
 891         if (executable)
 892                 set_memory_x(addr, npages);
 893         else
 894                 set_memory_nx(addr, npages);
 895 }
 896
 897 static void __init runtime_code_page_mkexec(void)
 898 {
 899         efi_memory_desc_t *md;
 900         void *p;
 901
 902         /* Make EFI runtime service code area executable */
 903         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 904                 md = p;
 905
 906                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 907                         continue;
 908
 909                 efi_set_executable(md, true);
 910         }
 911 }
 912
 913 /*
 914  * We can't ioremap data in EFI boot services RAM, because we've already mapped
 915  * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
 916  * callable after efi_enter_virtual_mode and before efi_free_boot_services.
 917  */
 918 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
 919 {
 920         void *p;
 921         if (WARN_ON(!memmap.map))
 922                 return NULL;
 923         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 924                 efi_memory_desc_t *md = p;
 925                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 926                 u64 end = md->phys_addr + size;
 927                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 928                     md->type != EFI_BOOT_SERVICES_CODE &&
 929                     md->type != EFI_BOOT_SERVICES_DATA)
 930                         continue;
 931                 if (!md->virt_addr)
 932                         continue;
 933                 if (phys_addr >= md->phys_addr && phys_addr < end) {
 934                         phys_addr += md->virt_addr - md->phys_addr;
 935                         return (__force void __iomem *)(unsigned long)phys_addr;
 936                 }
 937         }
 938         return NULL;
 939 }
 940
 941 void efi_memory_uc(u64 addr, unsigned long size)
 942 {
 943         unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
 944         u64 npages;
 945
 946         npages = round_up(size, page_shift) / page_shift;
 947         memrange_efi_to_native(&addr, &npages);
 948         set_memory_uc(addr, npages);
 949 }
 950
 951 /*
 952  * This function will switch the EFI runtime services to virtual mode.
 953  * Essentially, look through the EFI memmap and map every region that
 954  * has the runtime attribute bit set in its memory descriptor and update
 955  * that memory descriptor with the virtual address obtained from ioremap().
 956  * This enables the runtime services to be called without having to
 957  * thunk back into physical mode for every invocation.
 958  */
 959 void __init efi_enter_virtual_mode(void)
 960 {
 961         efi_memory_desc_t *md, *prev_md = NULL;
 962         efi_status_t status;
 963         unsigned long size;
 964         u64 end, systab, start_pfn, end_pfn;
 965         void *p, *va, *new_memmap = NULL;
 966         int count = 0;
 967
 968         efi.systab = NULL;
 969
 970         /*
 971          * We don't do virtual mode, since we don't do runtime services, on
 972          * non-native EFI
 973          */
 974
 975         if (!efi_is_native()) {
 976                 efi_unmap_memmap();
 977                 return;
 978         }
 979
 980         /* Merge contiguous regions of the same type and attribute */
 981         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 982                 u64 prev_size;
 983                 md = p;
 984
 985                 if (!prev_md) {
 986                         prev_md = md;
 987                         continue;
 988                 }
 989
 990                 if (prev_md->type != md->type ||
 991                     prev_md->attribute != md->attribute) {
 992                         prev_md = md;
 993                         continue;
 994                 }
 995
 996                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 997
 998                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 999                         prev_md->num_pages += md->num_pages;
1000                         md->type = EFI_RESERVED_TYPE;
1001                         md->attribute = 0;
1002                         continue;
1003                 }
1004                 prev_md = md;
1005         }
1006
1007         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1008                 md = p;
1009                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
1010                     md->type != EFI_BOOT_SERVICES_CODE &&
1011                     md->type != EFI_BOOT_SERVICES_DATA)
1012                         continue;
1013
1014                 size = md->num_pages << EFI_PAGE_SHIFT;
1015                 end = md->phys_addr + size;
1016
1017                 start_pfn = PFN_DOWN(md->phys_addr);
1018                 end_pfn = PFN_UP(end);
1019                 if (pfn_range_is_mapped(start_pfn, end_pfn)) {
1020                         va = __va(md->phys_addr);
1021
1022                         if (!(md->attribute & EFI_MEMORY_WB))
1023                                 efi_memory_uc((u64)(unsigned long)va, size);
1024                 } else
1025                         va = efi_ioremap(md->phys_addr, size,
1026                                          md->type, md->attribute);
1027
1028                 md->virt_addr = (u64) (unsigned long) va;
1029
1030                 if (!va) {
1031                         pr_err("ioremap of 0x%llX failed!\n",
1032                                (unsigned long long)md->phys_addr);
1033                         continue;
1034                 }
1035
1036                 systab = (u64) (unsigned long) efi_phys.systab;
1037                 if (md->phys_addr <= systab && systab < end) {
1038                         systab += md->virt_addr - md->phys_addr;
1039                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
1040                 }
1041                 new_memmap = krealloc(new_memmap,
1042                                       (count + 1) * memmap.desc_size,
1043                                       GFP_KERNEL);
1044                 memcpy(new_memmap + (count * memmap.desc_size), md,
1045                        memmap.desc_size);
1046                 count++;
1047         }
1048
1049         BUG_ON(!efi.systab);
1050
1051         status = phys_efi_set_virtual_address_map(
1052                 memmap.desc_size * count,
1053                 memmap.desc_size,
1054                 memmap.desc_version,
1055                 (efi_memory_desc_t *)__pa(new_memmap));
1056
1057         if (status != EFI_SUCCESS) {
1058                 pr_alert("Unable to switch EFI into virtual mode "
1059                          "(status=%lx)!\n", status);
1060                 panic("EFI call to SetVirtualAddressMap() failed!");
1061         }
1062
1063         /*
1064          * Now that EFI is in virtual mode, update the function
1065          * pointers in the runtime service table to the new virtual addresses.
1066          *
1067          * Call EFI services through wrapper functions.
1068          */
1069         efi.runtime_version = efi_systab.hdr.revision;
1070         efi.get_time = virt_efi_get_time;
1071         efi.set_time = virt_efi_set_time;
1072         efi.get_wakeup_time = virt_efi_get_wakeup_time;
1073         efi.set_wakeup_time = virt_efi_set_wakeup_time;
1074         efi.get_variable = virt_efi_get_variable;
1075         efi.get_next_variable = virt_efi_get_next_variable;
1076         efi.set_variable = virt_efi_set_variable;
1077         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
1078         efi.reset_system = virt_efi_reset_system;
1079         efi.set_virtual_address_map = NULL;
1080         efi.query_variable_info = virt_efi_query_variable_info;
1081         efi.update_capsule = virt_efi_update_capsule;
1082         efi.query_capsule_caps = virt_efi_query_capsule_caps;
1083         if (__supported_pte_mask & _PAGE_NX)
1084                 runtime_code_page_mkexec();
1085
1086         kfree(new_memmap);
1087 }
1088
1089 /*
1090  * Convenience functions to obtain memory types and attributes
1091  */
1092 u32 efi_mem_type(unsigned long phys_addr)
1093 {
1094         efi_memory_desc_t *md;
1095         void *p;
1096
1097         if (!efi_enabled(EFI_MEMMAP))
1098                 return 0;
1099
1100         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1101                 md = p;
1102                 if ((md->phys_addr <= phys_addr) &&
1103                     (phys_addr < (md->phys_addr +
1104                                   (md->num_pages << EFI_PAGE_SHIFT))))
1105                         return md->type;
1106         }
1107         return 0;
1108 }
1109
1110 u64 efi_mem_attributes(unsigned long phys_addr)
1111 {
1112         efi_memory_desc_t *md;
1113         void *p;
1114
1115         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1116                 md = p;
1117                 if ((md->phys_addr <= phys_addr) &&
1118                     (phys_addr < (md->phys_addr +
1119                                   (md->num_pages << EFI_PAGE_SHIFT))))
1120                         return md->attribute;
1121         }
1122         return 0;
1123 }
1124
1125 /*
1126  * Some firmware has serious problems when using more than 50% of the EFI
1127  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
1128  * we never use more than this safe limit.
1129  *
1130  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
1131  * store.
1132  */
1133 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
1134 {
1135         efi_status_t status;
1136         u64 storage_size, remaining_size, max_size;
1137
1138         status = efi.query_variable_info(attributes, &storage_size,
1139                                          &remaining_size, &max_size);
1140         if (status != EFI_SUCCESS)
1141                 return status;
1142
1143         if (!max_size && remaining_size > size)
1144                 printk_once(KERN_ERR FW_BUG "Broken EFI implementation"
1145                             " is returning MaxVariableSize=0\n");
1146         /*
1147          * Some firmware implementations refuse to boot if there's insufficient
1148          * space in the variable store. We account for that by refusing the
1149          * write if permitting it would reduce the available space to under
1150          * 50%. However, some firmware won't reclaim variable space until
1151          * after the used (not merely the actively used) space drops below
1152          * a threshold. We can approximate that case with the value calculated
1153          * above. If both the firmware and our calculations indicate that the
1154          * available space would drop below 50%, refuse the write.
1155          */
1156
1157         if (!storage_size || size > remaining_size ||
1158             (max_size && size > max_size))
1159                 return EFI_OUT_OF_RESOURCES;
1160
1161         if (!efi_no_storage_paranoia &&
1162             ((active_size + size + VAR_METADATA_SIZE > storage_size / 2) &&
1163              (remaining_size - size < storage_size / 2)))
1164                 return EFI_OUT_OF_RESOURCES;
1165
1166         return EFI_SUCCESS;
1167 }
1168 EXPORT_SYMBOL_GPL(efi_query_variable_store);