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         unsigned long pmap;
 457
 458 #ifdef CONFIG_X86_32
 459         /* Can't handle data above 4GB at this time */
 460         if (boot_params.efi_info.efi_memmap_hi) {
 461                 pr_err("Memory map is above 4GB, disabling EFI.\n");
 462                 return -EINVAL;
 463         }
 464         pmap = boot_params.efi_info.efi_memmap;
 465 #else
 466         pmap = (boot_params.efi_info.efi_memmap |
 467                 ((__u64)boot_params.efi_info.efi_memmap_hi<<32));
 468 #endif
 469         memmap.phys_map = (void *)pmap;
 470         memmap.nr_map = boot_params.efi_info.efi_memmap_size /
 471                 boot_params.efi_info.efi_memdesc_size;
 472         memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
 473         memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
 474         memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 475
 476         return 0;
 477 }
 478
 479 #if EFI_DEBUG
 480 static void __init print_efi_memmap(void)
 481 {
 482         efi_memory_desc_t *md;
 483         void *p;
 484         int i;
 485
 486         for (p = memmap.map, i = 0;
 487              p < memmap.map_end;
 488              p += memmap.desc_size, i++) {
 489                 md = p;
 490                 pr_info("mem%02u: type=%u, attr=0x%llx, "
 491                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 492                         i, md->type, md->attribute, md->phys_addr,
 493                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 494                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 495         }
 496 }
 497 #endif  /*  EFI_DEBUG  */
 498
 499 void __init efi_reserve_boot_services(void)
 500 {
 501         void *p;
 502
 503         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 504                 efi_memory_desc_t *md = p;
 505                 u64 start = md->phys_addr;
 506                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 507
 508                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 509                     md->type != EFI_BOOT_SERVICES_DATA)
 510                         continue;
 511                 /* Only reserve where possible:
 512                  * - Not within any already allocated areas
 513                  * - Not over any memory area (really needed, if above?)
 514                  * - Not within any part of the kernel
 515                  * - Not the bios reserved area
 516                 */
 517                 if ((start+size >= __pa_symbol(_text)
 518                                 && start <= __pa_symbol(_end)) ||
 519                         !e820_all_mapped(start, start+size, E820_RAM) ||
 520                         memblock_is_region_reserved(start, size)) {
 521                         /* Could not reserve, skip it */
 522                         md->num_pages = 0;
 523                         memblock_dbg("Could not reserve boot range "
 524                                         "[0x%010llx-0x%010llx]\n",
 525                                                 start, start+size-1);
 526                 } else
 527                         memblock_reserve(start, size);
 528         }
 529 }
 530
 531 void __init efi_unmap_memmap(void)
 532 {
 533         clear_bit(EFI_MEMMAP, &x86_efi_facility);
 534         if (memmap.map) {
 535                 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 536                 memmap.map = NULL;
 537         }
 538 }
 539
 540 void __init efi_free_boot_services(void)
 541 {
 542         void *p;
 543
 544         if (!efi_is_native())
 545                 return;
 546
 547         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 548                 efi_memory_desc_t *md = p;
 549                 unsigned long long start = md->phys_addr;
 550                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 551
 552                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 553                     md->type != EFI_BOOT_SERVICES_DATA)
 554                         continue;
 555
 556                 /* Could not reserve boot area */
 557                 if (!size)
 558                         continue;
 559
 560                 free_bootmem_late(start, size);
 561         }
 562
 563         efi_unmap_memmap();
 564 }
 565
 566 static int __init efi_systab_init(void *phys)
 567 {
 568         if (efi_enabled(EFI_64BIT)) {
 569                 efi_system_table_64_t *systab64;
 570                 u64 tmp = 0;
 571
 572                 systab64 = early_ioremap((unsigned long)phys,
 573                                          sizeof(*systab64));
 574                 if (systab64 == NULL) {
 575                         pr_err("Couldn't map the system table!\n");
 576                         return -ENOMEM;
 577                 }
 578
 579                 efi_systab.hdr = systab64->hdr;
 580                 efi_systab.fw_vendor = systab64->fw_vendor;
 581                 tmp |= systab64->fw_vendor;
 582                 efi_systab.fw_revision = systab64->fw_revision;
 583                 efi_systab.con_in_handle = systab64->con_in_handle;
 584                 tmp |= systab64->con_in_handle;
 585                 efi_systab.con_in = systab64->con_in;
 586                 tmp |= systab64->con_in;
 587                 efi_systab.con_out_handle = systab64->con_out_handle;
 588                 tmp |= systab64->con_out_handle;
 589                 efi_systab.con_out = systab64->con_out;
 590                 tmp |= systab64->con_out;
 591                 efi_systab.stderr_handle = systab64->stderr_handle;
 592                 tmp |= systab64->stderr_handle;
 593                 efi_systab.stderr = systab64->stderr;
 594                 tmp |= systab64->stderr;
 595                 efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
 596                 tmp |= systab64->runtime;
 597                 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
 598                 tmp |= systab64->boottime;
 599                 efi_systab.nr_tables = systab64->nr_tables;
 600                 efi_systab.tables = systab64->tables;
 601                 tmp |= systab64->tables;
 602
 603                 early_iounmap(systab64, sizeof(*systab64));
 604 #ifdef CONFIG_X86_32
 605                 if (tmp >> 32) {
 606                         pr_err("EFI data located above 4GB, disabling EFI.\n");
 607                         return -EINVAL;
 608                 }
 609 #endif
 610         } else {
 611                 efi_system_table_32_t *systab32;
 612
 613                 systab32 = early_ioremap((unsigned long)phys,
 614                                          sizeof(*systab32));
 615                 if (systab32 == NULL) {
 616                         pr_err("Couldn't map the system table!\n");
 617                         return -ENOMEM;
 618                 }
 619
 620                 efi_systab.hdr = systab32->hdr;
 621                 efi_systab.fw_vendor = systab32->fw_vendor;
 622                 efi_systab.fw_revision = systab32->fw_revision;
 623                 efi_systab.con_in_handle = systab32->con_in_handle;
 624                 efi_systab.con_in = systab32->con_in;
 625                 efi_systab.con_out_handle = systab32->con_out_handle;
 626                 efi_systab.con_out = systab32->con_out;
 627                 efi_systab.stderr_handle = systab32->stderr_handle;
 628                 efi_systab.stderr = systab32->stderr;
 629                 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
 630                 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
 631                 efi_systab.nr_tables = systab32->nr_tables;
 632                 efi_systab.tables = systab32->tables;
 633
 634                 early_iounmap(systab32, sizeof(*systab32));
 635         }
 636
 637         efi.systab = &efi_systab;
 638
 639         /*
 640          * Verify the EFI Table
 641          */
 642         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
 643                 pr_err("System table signature incorrect!\n");
 644                 return -EINVAL;
 645         }
 646         if ((efi.systab->hdr.revision >> 16) == 0)
 647                 pr_err("Warning: System table version "
 648                        "%d.%02d, expected 1.00 or greater!\n",
 649                        efi.systab->hdr.revision >> 16,
 650                        efi.systab->hdr.revision & 0xffff);
 651
 652         return 0;
 653 }
 654
 655 static int __init efi_config_init(u64 tables, int nr_tables)
 656 {
 657         void *config_tables, *tablep;
 658         int i, sz;
 659
 660         if (efi_enabled(EFI_64BIT))
 661                 sz = sizeof(efi_config_table_64_t);
 662         else
 663                 sz = sizeof(efi_config_table_32_t);
 664
 665         /*
 666          * Let's see what config tables the firmware passed to us.
 667          */
 668         config_tables = early_ioremap(tables, nr_tables * sz);
 669         if (config_tables == NULL) {
 670                 pr_err("Could not map Configuration table!\n");
 671                 return -ENOMEM;
 672         }
 673
 674         tablep = config_tables;
 675         pr_info("");
 676         for (i = 0; i < efi.systab->nr_tables; i++) {
 677                 efi_guid_t guid;
 678                 unsigned long table;
 679
 680                 if (efi_enabled(EFI_64BIT)) {
 681                         u64 table64;
 682                         guid = ((efi_config_table_64_t *)tablep)->guid;
 683                         table64 = ((efi_config_table_64_t *)tablep)->table;
 684                         table = table64;
 685 #ifdef CONFIG_X86_32
 686                         if (table64 >> 32) {
 687                                 pr_cont("\n");
 688                                 pr_err("Table located above 4GB, disabling EFI.\n");
 689                                 early_iounmap(config_tables,
 690                                               efi.systab->nr_tables * sz);
 691                                 return -EINVAL;
 692                         }
 693 #endif
 694                 } else {
 695                         guid = ((efi_config_table_32_t *)tablep)->guid;
 696                         table = ((efi_config_table_32_t *)tablep)->table;
 697                 }
 698                 if (!efi_guidcmp(guid, MPS_TABLE_GUID)) {
 699                         efi.mps = table;
 700                         pr_cont(" MPS=0x%lx ", table);
 701                 } else if (!efi_guidcmp(guid, ACPI_20_TABLE_GUID)) {
 702                         efi.acpi20 = table;
 703                         pr_cont(" ACPI 2.0=0x%lx ", table);
 704                 } else if (!efi_guidcmp(guid, ACPI_TABLE_GUID)) {
 705                         efi.acpi = table;
 706                         pr_cont(" ACPI=0x%lx ", table);
 707                 } else if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID)) {
 708                         efi.smbios = table;
 709                         pr_cont(" SMBIOS=0x%lx ", table);
 710 #ifdef CONFIG_X86_UV
 711                 } else if (!efi_guidcmp(guid, UV_SYSTEM_TABLE_GUID)) {
 712                         efi.uv_systab = table;
 713                         pr_cont(" UVsystab=0x%lx ", table);
 714 #endif
 715                 } else if (!efi_guidcmp(guid, HCDP_TABLE_GUID)) {
 716                         efi.hcdp = table;
 717                         pr_cont(" HCDP=0x%lx ", table);
 718                 } else if (!efi_guidcmp(guid, UGA_IO_PROTOCOL_GUID)) {
 719                         efi.uga = table;
 720                         pr_cont(" UGA=0x%lx ", table);
 721                 }
 722                 tablep += sz;
 723         }
 724         pr_cont("\n");
 725         early_iounmap(config_tables, efi.systab->nr_tables * sz);
 726         return 0;
 727 }
 728
 729 static int __init efi_runtime_init(void)
 730 {
 731         efi_runtime_services_t *runtime;
 732
 733         /*
 734          * Check out the runtime services table. We need to map
 735          * the runtime services table so that we can grab the physical
 736          * address of several of the EFI runtime functions, needed to
 737          * set the firmware into virtual mode.
 738          */
 739         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 740                                 sizeof(efi_runtime_services_t));
 741         if (!runtime) {
 742                 pr_err("Could not map the runtime service table!\n");
 743                 return -ENOMEM;
 744         }
 745         /*
 746          * We will only need *early* access to the following
 747          * two EFI runtime services before set_virtual_address_map
 748          * is invoked.
 749          */
 750         efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 751         efi_phys.set_virtual_address_map =
 752                 (efi_set_virtual_address_map_t *)
 753                 runtime->set_virtual_address_map;
 754         /*
 755          * Make efi_get_time can be called before entering
 756          * virtual mode.
 757          */
 758         efi.get_time = phys_efi_get_time;
 759         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 760
 761         return 0;
 762 }
 763
 764 static int __init efi_memmap_init(void)
 765 {
 766         /* Map the EFI memory map */
 767         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 768                                    memmap.nr_map * memmap.desc_size);
 769         if (memmap.map == NULL) {
 770                 pr_err("Could not map the memory map!\n");
 771                 return -ENOMEM;
 772         }
 773         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 774
 775         if (add_efi_memmap)
 776                 do_add_efi_memmap();
 777
 778         return 0;
 779 }
 780
 781 void __init efi_init(void)
 782 {
 783         efi_char16_t *c16;
 784         char vendor[100] = "unknown";
 785         int i = 0;
 786         void *tmp;
 787         struct setup_data *data;
 788         struct efi_var_bootdata *efi_var_data;
 789         u64 pa_data;
 790
 791 #ifdef CONFIG_X86_32
 792         if (boot_params.efi_info.efi_systab_hi ||
 793             boot_params.efi_info.efi_memmap_hi) {
 794                 pr_info("Table located above 4GB, disabling EFI.\n");
 795                 return;
 796         }
 797         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 798 #else
 799         efi_phys.systab = (efi_system_table_t *)
 800                           (boot_params.efi_info.efi_systab |
 801                           ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 802 #endif
 803
 804         if (efi_systab_init(efi_phys.systab))
 805                 return;
 806
 807         pa_data = boot_params.hdr.setup_data;
 808         while (pa_data) {
 809                 data = early_ioremap(pa_data, sizeof(*efi_var_data));
 810                 if (data->type == SETUP_EFI_VARS) {
 811                         efi_var_data = (struct efi_var_bootdata *)data;
 812
 813                         efi_var_store_size = efi_var_data->store_size;
 814                         efi_var_remaining_size = efi_var_data->remaining_size;
 815                         efi_var_max_var_size = efi_var_data->max_var_size;
 816                 }
 817                 pa_data = data->next;
 818                 early_iounmap(data, sizeof(*efi_var_data));
 819         }
 820
 821         boot_used_size = efi_var_store_size - efi_var_remaining_size;
 822
 823         set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
 824
 825         /*
 826          * Show what we know for posterity
 827          */
 828         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 829         if (c16) {
 830                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 831                         vendor[i] = *c16++;
 832                 vendor[i] = '\0';
 833         } else
 834                 pr_err("Could not map the firmware vendor!\n");
 835         early_iounmap(tmp, 2);
 836
 837         pr_info("EFI v%u.%.02u by %s\n",
 838                 efi.systab->hdr.revision >> 16,
 839                 efi.systab->hdr.revision & 0xffff, vendor);
 840
 841         if (efi_config_init(efi.systab->tables, efi.systab->nr_tables))
 842                 return;
 843
 844         set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
 845
 846         /*
 847          * Note: We currently don't support runtime services on an EFI
 848          * that doesn't match the kernel 32/64-bit mode.
 849          */
 850
 851         if (!efi_is_native())
 852                 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 853         else {
 854                 if (disable_runtime || efi_runtime_init())
 855                         return;
 856                 set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
 857         }
 858
 859         if (efi_memmap_init())
 860                 return;
 861
 862         set_bit(EFI_MEMMAP, &x86_efi_facility);
 863
 864 #ifdef CONFIG_X86_32
 865         if (efi_is_native()) {
 866                 x86_platform.get_wallclock = efi_get_time;
 867                 x86_platform.set_wallclock = efi_set_rtc_mmss;
 868         }
 869 #endif
 870
 871 #if EFI_DEBUG
 872         print_efi_memmap();
 873 #endif
 874 }
 875
 876 void __init efi_late_init(void)
 877 {
 878         efi_bgrt_init();
 879 }
 880
 881 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 882 {
 883         u64 addr, npages;
 884
 885         addr = md->virt_addr;
 886         npages = md->num_pages;
 887
 888         memrange_efi_to_native(&addr, &npages);
 889
 890         if (executable)
 891                 set_memory_x(addr, npages);
 892         else
 893                 set_memory_nx(addr, npages);
 894 }
 895
 896 static void __init runtime_code_page_mkexec(void)
 897 {
 898         efi_memory_desc_t *md;
 899         void *p;
 900
 901         /* Make EFI runtime service code area executable */
 902         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 903                 md = p;
 904
 905                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 906                         continue;
 907
 908                 efi_set_executable(md, true);
 909         }
 910 }
 911
 912 /*
 913  * We can't ioremap data in EFI boot services RAM, because we've already mapped
 914  * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
 915  * callable after efi_enter_virtual_mode and before efi_free_boot_services.
 916  */
 917 void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
 918 {
 919         void *p;
 920         if (WARN_ON(!memmap.map))
 921                 return NULL;
 922         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 923                 efi_memory_desc_t *md = p;
 924                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 925                 u64 end = md->phys_addr + size;
 926                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 927                     md->type != EFI_BOOT_SERVICES_CODE &&
 928                     md->type != EFI_BOOT_SERVICES_DATA)
 929                         continue;
 930                 if (!md->virt_addr)
 931                         continue;
 932                 if (phys_addr >= md->phys_addr && phys_addr < end) {
 933                         phys_addr += md->virt_addr - md->phys_addr;
 934                         return (__force void __iomem *)(unsigned long)phys_addr;
 935                 }
 936         }
 937         return NULL;
 938 }
 939
 940 void efi_memory_uc(u64 addr, unsigned long size)
 941 {
 942         unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
 943         u64 npages;
 944
 945         npages = round_up(size, page_shift) / page_shift;
 946         memrange_efi_to_native(&addr, &npages);
 947         set_memory_uc(addr, npages);
 948 }
 949
 950 /*
 951  * This function will switch the EFI runtime services to virtual mode.
 952  * Essentially, look through the EFI memmap and map every region that
 953  * has the runtime attribute bit set in its memory descriptor and update
 954  * that memory descriptor with the virtual address obtained from ioremap().
 955  * This enables the runtime services to be called without having to
 956  * thunk back into physical mode for every invocation.
 957  */
 958 void __init efi_enter_virtual_mode(void)
 959 {
 960         efi_memory_desc_t *md, *prev_md = NULL;
 961         efi_status_t status;
 962         unsigned long size;
 963         u64 end, systab, start_pfn, end_pfn;
 964         void *p, *va, *new_memmap = NULL;
 965         int count = 0;
 966
 967         efi.systab = NULL;
 968
 969         /*
 970          * We don't do virtual mode, since we don't do runtime services, on
 971          * non-native EFI
 972          */
 973
 974         if (!efi_is_native()) {
 975                 efi_unmap_memmap();
 976                 return;
 977         }
 978
 979         /* Merge contiguous regions of the same type and attribute */
 980         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 981                 u64 prev_size;
 982                 md = p;
 983
 984                 if (!prev_md) {
 985                         prev_md = md;
 986                         continue;
 987                 }
 988
 989                 if (prev_md->type != md->type ||
 990                     prev_md->attribute != md->attribute) {
 991                         prev_md = md;
 992                         continue;
 993                 }
 994
 995                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 996
 997                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 998                         prev_md->num_pages += md->num_pages;
 999                         md->type = EFI_RESERVED_TYPE;
1000                         md->attribute = 0;
1001                         continue;
1002                 }
1003                 prev_md = md;
1004         }
1005
1006         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1007                 md = p;
1008                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
1009                     md->type != EFI_BOOT_SERVICES_CODE &&
1010                     md->type != EFI_BOOT_SERVICES_DATA)
1011                         continue;
1012
1013                 size = md->num_pages << EFI_PAGE_SHIFT;
1014                 end = md->phys_addr + size;
1015
1016                 start_pfn = PFN_DOWN(md->phys_addr);
1017                 end_pfn = PFN_UP(end);
1018                 if (pfn_range_is_mapped(start_pfn, end_pfn)) {
1019                         va = __va(md->phys_addr);
1020
1021                         if (!(md->attribute & EFI_MEMORY_WB))
1022                                 efi_memory_uc((u64)(unsigned long)va, size);
1023                 } else
1024                         va = efi_ioremap(md->phys_addr, size,
1025                                          md->type, md->attribute);
1026
1027                 md->virt_addr = (u64) (unsigned long) va;
1028
1029                 if (!va) {
1030                         pr_err("ioremap of 0x%llX failed!\n",
1031                                (unsigned long long)md->phys_addr);
1032                         continue;
1033                 }
1034
1035                 systab = (u64) (unsigned long) efi_phys.systab;
1036                 if (md->phys_addr <= systab && systab < end) {
1037                         systab += md->virt_addr - md->phys_addr;
1038                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
1039                 }
1040                 new_memmap = krealloc(new_memmap,
1041                                       (count + 1) * memmap.desc_size,
1042                                       GFP_KERNEL);
1043                 memcpy(new_memmap + (count * memmap.desc_size), md,
1044                        memmap.desc_size);
1045                 count++;
1046         }
1047
1048         BUG_ON(!efi.systab);
1049
1050         status = phys_efi_set_virtual_address_map(
1051                 memmap.desc_size * count,
1052                 memmap.desc_size,
1053                 memmap.desc_version,
1054                 (efi_memory_desc_t *)__pa(new_memmap));
1055
1056         if (status != EFI_SUCCESS) {
1057                 pr_alert("Unable to switch EFI into virtual mode "
1058                          "(status=%lx)!\n", status);
1059                 panic("EFI call to SetVirtualAddressMap() failed!");
1060         }
1061
1062         /*
1063          * Now that EFI is in virtual mode, update the function
1064          * pointers in the runtime service table to the new virtual addresses.
1065          *
1066          * Call EFI services through wrapper functions.
1067          */
1068         efi.runtime_version = efi_systab.hdr.revision;
1069         efi.get_time = virt_efi_get_time;
1070         efi.set_time = virt_efi_set_time;
1071         efi.get_wakeup_time = virt_efi_get_wakeup_time;
1072         efi.set_wakeup_time = virt_efi_set_wakeup_time;
1073         efi.get_variable = virt_efi_get_variable;
1074         efi.get_next_variable = virt_efi_get_next_variable;
1075         efi.set_variable = virt_efi_set_variable;
1076         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
1077         efi.reset_system = virt_efi_reset_system;
1078         efi.set_virtual_address_map = NULL;
1079         efi.query_variable_info = virt_efi_query_variable_info;
1080         efi.update_capsule = virt_efi_update_capsule;
1081         efi.query_capsule_caps = virt_efi_query_capsule_caps;
1082         if (__supported_pte_mask & _PAGE_NX)
1083                 runtime_code_page_mkexec();
1084
1085         kfree(new_memmap);
1086 }
1087
1088 /*
1089  * Convenience functions to obtain memory types and attributes
1090  */
1091 u32 efi_mem_type(unsigned long phys_addr)
1092 {
1093         efi_memory_desc_t *md;
1094         void *p;
1095
1096         if (!efi_enabled(EFI_MEMMAP))
1097                 return 0;
1098
1099         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1100                 md = p;
1101                 if ((md->phys_addr <= phys_addr) &&
1102                     (phys_addr < (md->phys_addr +
1103                                   (md->num_pages << EFI_PAGE_SHIFT))))
1104                         return md->type;
1105         }
1106         return 0;
1107 }
1108
1109 u64 efi_mem_attributes(unsigned long phys_addr)
1110 {
1111         efi_memory_desc_t *md;
1112         void *p;
1113
1114         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
1115                 md = p;
1116                 if ((md->phys_addr <= phys_addr) &&
1117                     (phys_addr < (md->phys_addr +
1118                                   (md->num_pages << EFI_PAGE_SHIFT))))
1119                         return md->attribute;
1120         }
1121         return 0;
1122 }
1123
1124 /*
1125  * Some firmware has serious problems when using more than 50% of the EFI
1126  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
1127  * we never use more than this safe limit.
1128  *
1129  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
1130  * store.
1131  */
1132 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
1133 {
1134         efi_status_t status;
1135         u64 storage_size, remaining_size, max_size;
1136
1137         status = efi.query_variable_info(attributes, &storage_size,
1138                                          &remaining_size, &max_size);
1139         if (status != EFI_SUCCESS)
1140                 return status;
1141
1142         if (!max_size && remaining_size > size)
1143                 printk_once(KERN_ERR FW_BUG "Broken EFI implementation"
1144                             " is returning MaxVariableSize=0\n");
1145         /*
1146          * Some firmware implementations refuse to boot if there's insufficient
1147          * space in the variable store. We account for that by refusing the
1148          * write if permitting it would reduce the available space to under
1149          * 50%. However, some firmware won't reclaim variable space until
1150          * after the used (not merely the actively used) space drops below
1151          * a threshold. We can approximate that case with the value calculated
1152          * above. If both the firmware and our calculations indicate that the
1153          * available space would drop below 50%, refuse the write.
1154          */
1155
1156         if (!storage_size || size > remaining_size ||
1157             (max_size && size > max_size))
1158                 return EFI_OUT_OF_RESOURCES;
1159
1160         if (!efi_no_storage_paranoia &&
1161             ((active_size + size + VAR_METADATA_SIZE > storage_size / 2) &&
1162              (remaining_size - size < storage_size / 2)))
1163                 return EFI_OUT_OF_RESOURCES;
1164
1165         return EFI_SUCCESS;
1166 }
1167 EXPORT_SYMBOL_GPL(efi_query_variable_store);