arch/x86/platform/efi/efi.c

   1 /*
   2  * Common EFI (Extensible Firmware Interface) support functions
   3  * Based on Extensible Firmware Interface Specification version 1.0
   4  *
   5  * Copyright (C) 1999 VA Linux Systems
   6  * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
   7  * Copyright (C) 1999-2002 Hewlett-Packard Co.
   8  *      David Mosberger-Tang <davidm@hpl.hp.com>
   9  *      Stephane Eranian <eranian@hpl.hp.com>
  10  * Copyright (C) 2005-2008 Intel Co.
  11  *      Fenghua Yu <fenghua.yu@intel.com>
  12  *      Bibo Mao <bibo.mao@intel.com>
  13  *      Chandramouli Narayanan <mouli@linux.intel.com>
  14  *      Huang Ying <ying.huang@intel.com>
  15  *
  16  * Copied from efi_32.c to eliminate the duplicated code between EFI
  17  * 32/64 support code. --ying 2007-10-26
  18  *
  19  * All EFI Runtime Services are not implemented yet as EFI only
  20  * supports physical mode addressing on SoftSDV. This is to be fixed
  21  * in a future version.  --drummond 1999-07-20
  22  *
  23  * Implemented EFI runtime services and virtual mode calls.  --davidm
  24  *
  25  * Goutham Rao: <goutham.rao@intel.com>
  26  *      Skip non-WB memory and ignore empty memory ranges.
  27  */
  28
  29 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  30
  31 #include <linux/kernel.h>
  32 #include <linux/init.h>
  33 #include <linux/efi.h>
  34 #include <linux/efi-bgrt.h>
  35 #include <linux/export.h>
  36 #include <linux/bootmem.h>
  37 #include <linux/slab.h>
  38 #include <linux/memblock.h>
  39 #include <linux/spinlock.h>
  40 #include <linux/uaccess.h>
  41 #include <linux/time.h>
  42 #include <linux/io.h>
  43 #include <linux/reboot.h>
  44 #include <linux/bcd.h>
  45
  46 #include <asm/setup.h>
  47 #include <asm/efi.h>
  48 #include <asm/time.h>
  49 #include <asm/cacheflush.h>
  50 #include <asm/tlbflush.h>
  51 #include <asm/x86_init.h>
  52 #include <asm/rtc.h>
  53
  54 #define EFI_DEBUG       1
  55
  56 #define EFI_MIN_RESERVE 5120
  57
  58 #define EFI_DUMMY_GUID \
  59         EFI_GUID(0x4424ac57, 0xbe4b, 0x47dd, 0x9e, 0x97, 0xed, 0x50, 0xf0, 0x9f, 0x92, 0xa9)
  60
  61 static efi_char16_t efi_dummy_name[6] = { 'D', 'U', 'M', 'M', 'Y', 0 };
  62
  63 struct efi_memory_map memmap;
  64
  65 static struct efi efi_phys __initdata;
  66 static efi_system_table_t efi_systab __initdata;
  67
  68 unsigned long x86_efi_facility;
  69
  70 static __initdata efi_config_table_type_t arch_tables[] = {
  71 #ifdef CONFIG_X86_UV
  72         {UV_SYSTEM_TABLE_GUID, "UVsystab", &efi.uv_systab},
  73 #endif
  74         {NULL_GUID, NULL, 0},
  75 };
  76
  77 /*
  78  * Returns 1 if 'facility' is enabled, 0 otherwise.
  79  */
  80 int efi_enabled(int facility)
  81 {
  82         return test_bit(facility, &x86_efi_facility) != 0;
  83 }
  84 EXPORT_SYMBOL(efi_enabled);
  85
  86 static bool __initdata disable_runtime = false;
  87 static int __init setup_noefi(char *arg)
  88 {
  89         disable_runtime = true;
  90         return 0;
  91 }
  92 early_param("noefi", setup_noefi);
  93
  94 int add_efi_memmap;
  95 EXPORT_SYMBOL(add_efi_memmap);
  96
  97 static int __init setup_add_efi_memmap(char *arg)
  98 {
  99         add_efi_memmap = 1;
 100         return 0;
 101 }
 102 early_param("add_efi_memmap", setup_add_efi_memmap);
 103
 104 static bool efi_no_storage_paranoia;
 105
 106 static int __init setup_storage_paranoia(char *arg)
 107 {
 108         efi_no_storage_paranoia = true;
 109         return 0;
 110 }
 111 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
 112
 113
 114 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 115 {
 116         unsigned long flags;
 117         efi_status_t status;
 118
 119         spin_lock_irqsave(&rtc_lock, flags);
 120         status = efi_call_virt2(get_time, tm, tc);
 121         spin_unlock_irqrestore(&rtc_lock, flags);
 122         return status;
 123 }
 124
 125 static efi_status_t virt_efi_set_time(efi_time_t *tm)
 126 {
 127         unsigned long flags;
 128         efi_status_t status;
 129
 130         spin_lock_irqsave(&rtc_lock, flags);
 131         status = efi_call_virt1(set_time, tm);
 132         spin_unlock_irqrestore(&rtc_lock, flags);
 133         return status;
 134 }
 135
 136 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
 137                                              efi_bool_t *pending,
 138                                              efi_time_t *tm)
 139 {
 140         unsigned long flags;
 141         efi_status_t status;
 142
 143         spin_lock_irqsave(&rtc_lock, flags);
 144         status = efi_call_virt3(get_wakeup_time,
 145                                 enabled, pending, tm);
 146         spin_unlock_irqrestore(&rtc_lock, flags);
 147         return status;
 148 }
 149
 150 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
 151 {
 152         unsigned long flags;
 153         efi_status_t status;
 154
 155         spin_lock_irqsave(&rtc_lock, flags);
 156         status = efi_call_virt2(set_wakeup_time,
 157                                 enabled, tm);
 158         spin_unlock_irqrestore(&rtc_lock, flags);
 159         return status;
 160 }
 161
 162 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
 163                                           efi_guid_t *vendor,
 164                                           u32 *attr,
 165                                           unsigned long *data_size,
 166                                           void *data)
 167 {
 168         return efi_call_virt5(get_variable,
 169                               name, vendor, attr,
 170                               data_size, data);
 171 }
 172
 173 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 174                                                efi_char16_t *name,
 175                                                efi_guid_t *vendor)
 176 {
 177         return efi_call_virt3(get_next_variable,
 178                               name_size, name, vendor);
 179 }
 180
 181 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 182                                           efi_guid_t *vendor,
 183                                           u32 attr,
 184                                           unsigned long data_size,
 185                                           void *data)
 186 {
 187         return efi_call_virt5(set_variable,
 188                               name, vendor, attr,
 189                               data_size, data);
 190 }
 191
 192 static efi_status_t virt_efi_query_variable_info(u32 attr,
 193                                                  u64 *storage_space,
 194                                                  u64 *remaining_space,
 195                                                  u64 *max_variable_size)
 196 {
 197         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 198                 return EFI_UNSUPPORTED;
 199
 200         return efi_call_virt4(query_variable_info, attr, storage_space,
 201                               remaining_space, max_variable_size);
 202 }
 203
 204 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 205 {
 206         return efi_call_virt1(get_next_high_mono_count, count);
 207 }
 208
 209 static void virt_efi_reset_system(int reset_type,
 210                                   efi_status_t status,
 211                                   unsigned long data_size,
 212                                   efi_char16_t *data)
 213 {
 214         efi_call_virt4(reset_system, reset_type, status,
 215                        data_size, data);
 216 }
 217
 218 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
 219                                             unsigned long count,
 220                                             unsigned long sg_list)
 221 {
 222         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 223                 return EFI_UNSUPPORTED;
 224
 225         return efi_call_virt3(update_capsule, capsules, count, sg_list);
 226 }
 227
 228 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
 229                                                 unsigned long count,
 230                                                 u64 *max_size,
 231                                                 int *reset_type)
 232 {
 233         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 234                 return EFI_UNSUPPORTED;
 235
 236         return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
 237                               reset_type);
 238 }
 239
 240 static efi_status_t __init phys_efi_set_virtual_address_map(
 241         unsigned long memory_map_size,
 242         unsigned long descriptor_size,
 243         u32 descriptor_version,
 244         efi_memory_desc_t *virtual_map)
 245 {
 246         efi_status_t status;
 247
 248         efi_call_phys_prelog();
 249         status = efi_call_phys4(efi_phys.set_virtual_address_map,
 250                                 memory_map_size, descriptor_size,
 251                                 descriptor_version, virtual_map);
 252         efi_call_phys_epilog();
 253         return status;
 254 }
 255
 256 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
 257                                              efi_time_cap_t *tc)
 258 {
 259         unsigned long flags;
 260         efi_status_t status;
 261
 262         spin_lock_irqsave(&rtc_lock, flags);
 263         efi_call_phys_prelog();
 264         status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
 265                                 virt_to_phys(tc));
 266         efi_call_phys_epilog();
 267         spin_unlock_irqrestore(&rtc_lock, flags);
 268         return status;
 269 }
 270
 271 int efi_set_rtc_mmss(unsigned long nowtime)
 272 {
 273         efi_status_t    status;
 274         efi_time_t      eft;
 275         efi_time_cap_t  cap;
 276         struct rtc_time tm;
 277
 278         status = efi.get_time(&eft, &cap);
 279         if (status != EFI_SUCCESS) {
 280                 pr_err("Oops: efitime: can't read time!\n");
 281                 return -1;
 282         }
 283
 284         rtc_time_to_tm(nowtime, &tm);
 285         if (!rtc_valid_tm(&tm)) {
 286                 eft.year = tm.tm_year + 1900;
 287                 eft.month = tm.tm_mon + 1;
 288                 eft.day = tm.tm_mday;
 289                 eft.minute = tm.tm_min;
 290                 eft.second = tm.tm_sec;
 291                 eft.nanosecond = 0;
 292         } else {
 293                 printk(KERN_ERR
 294                        "%s: Invalid EFI RTC value: write of %lx to EFI RTC failed\n",
 295                        __FUNCTION__, nowtime);
 296                 return -1;
 297         }
 298
 299         status = efi.set_time(&eft);
 300         if (status != EFI_SUCCESS) {
 301                 pr_err("Oops: efitime: can't write time!\n");
 302                 return -1;
 303         }
 304         return 0;
 305 }
 306
 307 unsigned long efi_get_time(void)
 308 {
 309         efi_status_t status;
 310         efi_time_t eft;
 311         efi_time_cap_t cap;
 312
 313         status = efi.get_time(&eft, &cap);
 314         if (status != EFI_SUCCESS)
 315                 pr_err("Oops: efitime: can't read time!\n");
 316
 317         return mktime(eft.year, eft.month, eft.day, eft.hour,
 318                       eft.minute, eft.second);
 319 }
 320
 321 /*
 322  * Tell the kernel about the EFI memory map.  This might include
 323  * more than the max 128 entries that can fit in the e820 legacy
 324  * (zeropage) memory map.
 325  */
 326
 327 static void __init do_add_efi_memmap(void)
 328 {
 329         void *p;
 330
 331         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 332                 efi_memory_desc_t *md = p;
 333                 unsigned long long start = md->phys_addr;
 334                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 335                 int e820_type;
 336
 337                 switch (md->type) {
 338                 case EFI_LOADER_CODE:
 339                 case EFI_LOADER_DATA:
 340                 case EFI_BOOT_SERVICES_CODE:
 341                 case EFI_BOOT_SERVICES_DATA:
 342                 case EFI_CONVENTIONAL_MEMORY:
 343                         if (md->attribute & EFI_MEMORY_WB)
 344                                 e820_type = E820_RAM;
 345                         else
 346                                 e820_type = E820_RESERVED;
 347                         break;
 348                 case EFI_ACPI_RECLAIM_MEMORY:
 349                         e820_type = E820_ACPI;
 350                         break;
 351                 case EFI_ACPI_MEMORY_NVS:
 352                         e820_type = E820_NVS;
 353                         break;
 354                 case EFI_UNUSABLE_MEMORY:
 355                         e820_type = E820_UNUSABLE;
 356                         break;
 357                 default:
 358                         /*
 359                          * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 360                          * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 361                          * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 362                          */
 363                         e820_type = E820_RESERVED;
 364                         break;
 365                 }
 366                 e820_add_region(start, size, e820_type);
 367         }
 368         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 369 }
 370
 371 int __init efi_memblock_x86_reserve_range(void)
 372 {
 373         struct efi_info *e = &boot_params.efi_info;
 374         unsigned long pmap;
 375
 376 #ifdef CONFIG_X86_32
 377         /* Can't handle data above 4GB at this time */
 378         if (e->efi_memmap_hi) {
 379                 pr_err("Memory map is above 4GB, disabling EFI.\n");
 380                 return -EINVAL;
 381         }
 382         pmap =  e->efi_memmap;
 383 #else
 384         pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
 385 #endif
 386         memmap.phys_map         = (void *)pmap;
 387         memmap.nr_map           = e->efi_memmap_size /
 388                                   e->efi_memdesc_size;
 389         memmap.desc_size        = e->efi_memdesc_size;
 390         memmap.desc_version     = e->efi_memdesc_version;
 391
 392         memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 393
 394         efi.memmap = &memmap;
 395
 396         return 0;
 397 }
 398
 399 #if EFI_DEBUG
 400 static void __init print_efi_memmap(void)
 401 {
 402         efi_memory_desc_t *md;
 403         void *p;
 404         int i;
 405
 406         for (p = memmap.map, i = 0;
 407              p < memmap.map_end;
 408              p += memmap.desc_size, i++) {
 409                 md = p;
 410                 pr_info("mem%02u: type=%u, attr=0x%llx, "
 411                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 412                         i, md->type, md->attribute, md->phys_addr,
 413                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 414                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 415         }
 416 }
 417 #endif  /*  EFI_DEBUG  */
 418
 419 void __init efi_reserve_boot_services(void)
 420 {
 421         void *p;
 422
 423         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 424                 efi_memory_desc_t *md = p;
 425                 u64 start = md->phys_addr;
 426                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 427
 428                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 429                     md->type != EFI_BOOT_SERVICES_DATA)
 430                         continue;
 431                 /* Only reserve where possible:
 432                  * - Not within any already allocated areas
 433                  * - Not over any memory area (really needed, if above?)
 434                  * - Not within any part of the kernel
 435                  * - Not the bios reserved area
 436                 */
 437                 if ((start+size >= __pa_symbol(_text)
 438                                 && start <= __pa_symbol(_end)) ||
 439                         !e820_all_mapped(start, start+size, E820_RAM) ||
 440                         memblock_is_region_reserved(start, size)) {
 441                         /* Could not reserve, skip it */
 442                         md->num_pages = 0;
 443                         memblock_dbg("Could not reserve boot range "
 444                                         "[0x%010llx-0x%010llx]\n",
 445                                                 start, start+size-1);
 446                 } else
 447                         memblock_reserve(start, size);
 448         }
 449 }
 450
 451 void __init efi_unmap_memmap(void)
 452 {
 453         clear_bit(EFI_MEMMAP, &x86_efi_facility);
 454         if (memmap.map) {
 455                 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 456                 memmap.map = NULL;
 457         }
 458 }
 459
 460 void __init efi_free_boot_services(void)
 461 {
 462         void *p;
 463
 464         if (!efi_is_native())
 465                 return;
 466
 467         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 468                 efi_memory_desc_t *md = p;
 469                 unsigned long long start = md->phys_addr;
 470                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 471
 472                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 473                     md->type != EFI_BOOT_SERVICES_DATA)
 474                         continue;
 475
 476                 /* Could not reserve boot area */
 477                 if (!size)
 478                         continue;
 479
 480                 free_bootmem_late(start, size);
 481         }
 482
 483         efi_unmap_memmap();
 484 }
 485
 486 static int __init efi_systab_init(void *phys)
 487 {
 488         if (efi_enabled(EFI_64BIT)) {
 489                 efi_system_table_64_t *systab64;
 490                 u64 tmp = 0;
 491
 492                 systab64 = early_ioremap((unsigned long)phys,
 493                                          sizeof(*systab64));
 494                 if (systab64 == NULL) {
 495                         pr_err("Couldn't map the system table!\n");
 496                         return -ENOMEM;
 497                 }
 498
 499                 efi_systab.hdr = systab64->hdr;
 500                 efi_systab.fw_vendor = systab64->fw_vendor;
 501                 tmp |= systab64->fw_vendor;
 502                 efi_systab.fw_revision = systab64->fw_revision;
 503                 efi_systab.con_in_handle = systab64->con_in_handle;
 504                 tmp |= systab64->con_in_handle;
 505                 efi_systab.con_in = systab64->con_in;
 506                 tmp |= systab64->con_in;
 507                 efi_systab.con_out_handle = systab64->con_out_handle;
 508                 tmp |= systab64->con_out_handle;
 509                 efi_systab.con_out = systab64->con_out;
 510                 tmp |= systab64->con_out;
 511                 efi_systab.stderr_handle = systab64->stderr_handle;
 512                 tmp |= systab64->stderr_handle;
 513                 efi_systab.stderr = systab64->stderr;
 514                 tmp |= systab64->stderr;
 515                 efi_systab.runtime = (void *)(unsigned long)systab64->runtime;
 516                 tmp |= systab64->runtime;
 517                 efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
 518                 tmp |= systab64->boottime;
 519                 efi_systab.nr_tables = systab64->nr_tables;
 520                 efi_systab.tables = systab64->tables;
 521                 tmp |= systab64->tables;
 522
 523                 early_iounmap(systab64, sizeof(*systab64));
 524 #ifdef CONFIG_X86_32
 525                 if (tmp >> 32) {
 526                         pr_err("EFI data located above 4GB, disabling EFI.\n");
 527                         return -EINVAL;
 528                 }
 529 #endif
 530         } else {
 531                 efi_system_table_32_t *systab32;
 532
 533                 systab32 = early_ioremap((unsigned long)phys,
 534                                          sizeof(*systab32));
 535                 if (systab32 == NULL) {
 536                         pr_err("Couldn't map the system table!\n");
 537                         return -ENOMEM;
 538                 }
 539
 540                 efi_systab.hdr = systab32->hdr;
 541                 efi_systab.fw_vendor = systab32->fw_vendor;
 542                 efi_systab.fw_revision = systab32->fw_revision;
 543                 efi_systab.con_in_handle = systab32->con_in_handle;
 544                 efi_systab.con_in = systab32->con_in;
 545                 efi_systab.con_out_handle = systab32->con_out_handle;
 546                 efi_systab.con_out = systab32->con_out;
 547                 efi_systab.stderr_handle = systab32->stderr_handle;
 548                 efi_systab.stderr = systab32->stderr;
 549                 efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
 550                 efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
 551                 efi_systab.nr_tables = systab32->nr_tables;
 552                 efi_systab.tables = systab32->tables;
 553
 554                 early_iounmap(systab32, sizeof(*systab32));
 555         }
 556
 557         efi.systab = &efi_systab;
 558
 559         /*
 560          * Verify the EFI Table
 561          */
 562         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
 563                 pr_err("System table signature incorrect!\n");
 564                 return -EINVAL;
 565         }
 566         if ((efi.systab->hdr.revision >> 16) == 0)
 567                 pr_err("Warning: System table version "
 568                        "%d.%02d, expected 1.00 or greater!\n",
 569                        efi.systab->hdr.revision >> 16,
 570                        efi.systab->hdr.revision & 0xffff);
 571
 572         return 0;
 573 }
 574
 575 static int __init efi_runtime_init(void)
 576 {
 577         efi_runtime_services_t *runtime;
 578
 579         /*
 580          * Check out the runtime services table. We need to map
 581          * the runtime services table so that we can grab the physical
 582          * address of several of the EFI runtime functions, needed to
 583          * set the firmware into virtual mode.
 584          */
 585         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 586                                 sizeof(efi_runtime_services_t));
 587         if (!runtime) {
 588                 pr_err("Could not map the runtime service table!\n");
 589                 return -ENOMEM;
 590         }
 591         /*
 592          * We will only need *early* access to the following
 593          * two EFI runtime services before set_virtual_address_map
 594          * is invoked.
 595          */
 596         efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 597         efi_phys.set_virtual_address_map =
 598                 (efi_set_virtual_address_map_t *)
 599                 runtime->set_virtual_address_map;
 600         /*
 601          * Make efi_get_time can be called before entering
 602          * virtual mode.
 603          */
 604         efi.get_time = phys_efi_get_time;
 605         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 606
 607         return 0;
 608 }
 609
 610 static int __init efi_memmap_init(void)
 611 {
 612         /* Map the EFI memory map */
 613         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 614                                    memmap.nr_map * memmap.desc_size);
 615         if (memmap.map == NULL) {
 616                 pr_err("Could not map the memory map!\n");
 617                 return -ENOMEM;
 618         }
 619         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 620
 621         if (add_efi_memmap)
 622                 do_add_efi_memmap();
 623
 624         return 0;
 625 }
 626
 627 void __init efi_init(void)
 628 {
 629         efi_char16_t *c16;
 630         char vendor[100] = "unknown";
 631         int i = 0;
 632         void *tmp;
 633
 634 #ifdef CONFIG_X86_32
 635         if (boot_params.efi_info.efi_systab_hi ||
 636             boot_params.efi_info.efi_memmap_hi) {
 637                 pr_info("Table located above 4GB, disabling EFI.\n");
 638                 return;
 639         }
 640         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 641 #else
 642         efi_phys.systab = (efi_system_table_t *)
 643                           (boot_params.efi_info.efi_systab |
 644                           ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 645 #endif
 646
 647         if (efi_systab_init(efi_phys.systab))
 648                 return;
 649
 650         set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
 651
 652         /*
 653          * Show what we know for posterity
 654          */
 655         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 656         if (c16) {
 657                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 658                         vendor[i] = *c16++;
 659                 vendor[i] = '\0';
 660         } else
 661                 pr_err("Could not map the firmware vendor!\n");
 662         early_iounmap(tmp, 2);
 663
 664         pr_info("EFI v%u.%.02u by %s\n",
 665                 efi.systab->hdr.revision >> 16,
 666                 efi.systab->hdr.revision & 0xffff, vendor);
 667
 668         if (efi_config_init(arch_tables))
 669                 return;
 670
 671         set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
 672
 673         /*
 674          * Note: We currently don't support runtime services on an EFI
 675          * that doesn't match the kernel 32/64-bit mode.
 676          */
 677
 678         if (!efi_is_native())
 679                 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
 680         else {
 681                 if (disable_runtime || efi_runtime_init())
 682                         return;
 683                 set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
 684         }
 685
 686         if (efi_memmap_init())
 687                 return;
 688
 689         set_bit(EFI_MEMMAP, &x86_efi_facility);
 690
 691 #ifdef CONFIG_X86_32
 692         if (efi_is_native()) {
 693                 x86_platform.get_wallclock = efi_get_time;
 694                 x86_platform.set_wallclock = efi_set_rtc_mmss;
 695         }
 696 #endif
 697
 698 #if EFI_DEBUG
 699         print_efi_memmap();
 700 #endif
 701 }
 702
 703 void __init efi_late_init(void)
 704 {
 705         efi_bgrt_init();
 706 }
 707
 708 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 709 {
 710         u64 addr, npages;
 711
 712         addr = md->virt_addr;
 713         npages = md->num_pages;
 714
 715         memrange_efi_to_native(&addr, &npages);
 716
 717         if (executable)
 718                 set_memory_x(addr, npages);
 719         else
 720                 set_memory_nx(addr, npages);
 721 }
 722
 723 static void __init runtime_code_page_mkexec(void)
 724 {
 725         efi_memory_desc_t *md;
 726         void *p;
 727
 728         /* Make EFI runtime service code area executable */
 729         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 730                 md = p;
 731
 732                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 733                         continue;
 734
 735                 efi_set_executable(md, true);
 736         }
 737 }
 738
 739 void efi_memory_uc(u64 addr, unsigned long size)
 740 {
 741         unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
 742         u64 npages;
 743
 744         npages = round_up(size, page_shift) / page_shift;
 745         memrange_efi_to_native(&addr, &npages);
 746         set_memory_uc(addr, npages);
 747 }
 748
 749 /*
 750  * This function will switch the EFI runtime services to virtual mode.
 751  * Essentially, look through the EFI memmap and map every region that
 752  * has the runtime attribute bit set in its memory descriptor and update
 753  * that memory descriptor with the virtual address obtained from ioremap().
 754  * This enables the runtime services to be called without having to
 755  * thunk back into physical mode for every invocation.
 756  */
 757 void __init efi_enter_virtual_mode(void)
 758 {
 759         efi_memory_desc_t *md, *prev_md = NULL;
 760         efi_status_t status;
 761         unsigned long size;
 762         u64 end, systab, start_pfn, end_pfn;
 763         void *p, *va, *new_memmap = NULL;
 764         int count = 0;
 765
 766         efi.systab = NULL;
 767
 768         /*
 769          * We don't do virtual mode, since we don't do runtime services, on
 770          * non-native EFI
 771          */
 772
 773         if (!efi_is_native()) {
 774                 efi_unmap_memmap();
 775                 return;
 776         }
 777
 778         /* Merge contiguous regions of the same type and attribute */
 779         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 780                 u64 prev_size;
 781                 md = p;
 782
 783                 if (!prev_md) {
 784                         prev_md = md;
 785                         continue;
 786                 }
 787
 788                 if (prev_md->type != md->type ||
 789                     prev_md->attribute != md->attribute) {
 790                         prev_md = md;
 791                         continue;
 792                 }
 793
 794                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 795
 796                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 797                         prev_md->num_pages += md->num_pages;
 798                         md->type = EFI_RESERVED_TYPE;
 799                         md->attribute = 0;
 800                         continue;
 801                 }
 802                 prev_md = md;
 803         }
 804
 805         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 806                 md = p;
 807                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 808                     md->type != EFI_BOOT_SERVICES_CODE &&
 809                     md->type != EFI_BOOT_SERVICES_DATA)
 810                         continue;
 811
 812                 size = md->num_pages << EFI_PAGE_SHIFT;
 813                 end = md->phys_addr + size;
 814
 815                 start_pfn = PFN_DOWN(md->phys_addr);
 816                 end_pfn = PFN_UP(end);
 817                 if (pfn_range_is_mapped(start_pfn, end_pfn)) {
 818                         va = __va(md->phys_addr);
 819
 820                         if (!(md->attribute & EFI_MEMORY_WB))
 821                                 efi_memory_uc((u64)(unsigned long)va, size);
 822                 } else
 823                         va = efi_ioremap(md->phys_addr, size,
 824                                          md->type, md->attribute);
 825
 826                 md->virt_addr = (u64) (unsigned long) va;
 827
 828                 if (!va) {
 829                         pr_err("ioremap of 0x%llX failed!\n",
 830                                (unsigned long long)md->phys_addr);
 831                         continue;
 832                 }
 833
 834                 systab = (u64) (unsigned long) efi_phys.systab;
 835                 if (md->phys_addr <= systab && systab < end) {
 836                         systab += md->virt_addr - md->phys_addr;
 837                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
 838                 }
 839                 new_memmap = krealloc(new_memmap,
 840                                       (count + 1) * memmap.desc_size,
 841                                       GFP_KERNEL);
 842                 memcpy(new_memmap + (count * memmap.desc_size), md,
 843                        memmap.desc_size);
 844                 count++;
 845         }
 846
 847         BUG_ON(!efi.systab);
 848
 849         status = phys_efi_set_virtual_address_map(
 850                 memmap.desc_size * count,
 851                 memmap.desc_size,
 852                 memmap.desc_version,
 853                 (efi_memory_desc_t *)__pa(new_memmap));
 854
 855         if (status != EFI_SUCCESS) {
 856                 pr_alert("Unable to switch EFI into virtual mode "
 857                          "(status=%lx)!\n", status);
 858                 panic("EFI call to SetVirtualAddressMap() failed!");
 859         }
 860
 861         /*
 862          * Now that EFI is in virtual mode, update the function
 863          * pointers in the runtime service table to the new virtual addresses.
 864          *
 865          * Call EFI services through wrapper functions.
 866          */
 867         efi.runtime_version = efi_systab.hdr.revision;
 868         efi.get_time = virt_efi_get_time;
 869         efi.set_time = virt_efi_set_time;
 870         efi.get_wakeup_time = virt_efi_get_wakeup_time;
 871         efi.set_wakeup_time = virt_efi_set_wakeup_time;
 872         efi.get_variable = virt_efi_get_variable;
 873         efi.get_next_variable = virt_efi_get_next_variable;
 874         efi.set_variable = virt_efi_set_variable;
 875         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
 876         efi.reset_system = virt_efi_reset_system;
 877         efi.set_virtual_address_map = NULL;
 878         efi.query_variable_info = virt_efi_query_variable_info;
 879         efi.update_capsule = virt_efi_update_capsule;
 880         efi.query_capsule_caps = virt_efi_query_capsule_caps;
 881         if (__supported_pte_mask & _PAGE_NX)
 882                 runtime_code_page_mkexec();
 883
 884         kfree(new_memmap);
 885
 886         /* clean DUMMY object */
 887         efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
 888                          EFI_VARIABLE_NON_VOLATILE |
 889                          EFI_VARIABLE_BOOTSERVICE_ACCESS |
 890                          EFI_VARIABLE_RUNTIME_ACCESS,
 891                          0, NULL);
 892 }
 893
 894 /*
 895  * Convenience functions to obtain memory types and attributes
 896  */
 897 u32 efi_mem_type(unsigned long phys_addr)
 898 {
 899         efi_memory_desc_t *md;
 900         void *p;
 901
 902         if (!efi_enabled(EFI_MEMMAP))
 903                 return 0;
 904
 905         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 906                 md = p;
 907                 if ((md->phys_addr <= phys_addr) &&
 908                     (phys_addr < (md->phys_addr +
 909                                   (md->num_pages << EFI_PAGE_SHIFT))))
 910                         return md->type;
 911         }
 912         return 0;
 913 }
 914
 915 u64 efi_mem_attributes(unsigned long phys_addr)
 916 {
 917         efi_memory_desc_t *md;
 918         void *p;
 919
 920         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 921                 md = p;
 922                 if ((md->phys_addr <= phys_addr) &&
 923                     (phys_addr < (md->phys_addr +
 924                                   (md->num_pages << EFI_PAGE_SHIFT))))
 925                         return md->attribute;
 926         }
 927         return 0;
 928 }
 929
 930 /*
 931  * Some firmware has serious problems when using more than 50% of the EFI
 932  * variable store, i.e. it triggers bugs that can brick machines. Ensure that
 933  * we never use more than this safe limit.
 934  *
 935  * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
 936  * store.
 937  */
 938 efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
 939 {
 940         efi_status_t status;
 941         u64 storage_size, remaining_size, max_size;
 942
 943         if (!(attributes & EFI_VARIABLE_NON_VOLATILE))
 944                 return 0;
 945
 946         status = efi.query_variable_info(attributes, &storage_size,
 947                                          &remaining_size, &max_size);
 948         if (status != EFI_SUCCESS)
 949                 return status;
 950
 951         /*
 952          * Some firmware implementations refuse to boot if there's insufficient
 953          * space in the variable store. We account for that by refusing the
 954          * write if permitting it would reduce the available space to under
 955          * 5KB. This figure was provided by Samsung, so should be safe.
 956          */
 957         if ((remaining_size - size < EFI_MIN_RESERVE) &&
 958                 !efi_no_storage_paranoia) {
 959
 960                 /*
 961                  * Triggering garbage collection may require that the firmware
 962                  * generate a real EFI_OUT_OF_RESOURCES error. We can force
 963                  * that by attempting to use more space than is available.
 964                  */
 965                 unsigned long dummy_size = remaining_size + 1024;
 966                 void *dummy = kzalloc(dummy_size, GFP_ATOMIC);
 967
 968                 if (!dummy)
 969                         return EFI_OUT_OF_RESOURCES;
 970
 971                 status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
 972                                           EFI_VARIABLE_NON_VOLATILE |
 973                                           EFI_VARIABLE_BOOTSERVICE_ACCESS |
 974                                           EFI_VARIABLE_RUNTIME_ACCESS,
 975                                           dummy_size, dummy);
 976
 977                 if (status == EFI_SUCCESS) {
 978                         /*
 979                          * This should have failed, so if it didn't make sure
 980                          * that we delete it...
 981                          */
 982                         efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
 983                                          EFI_VARIABLE_NON_VOLATILE |
 984                                          EFI_VARIABLE_BOOTSERVICE_ACCESS |
 985                                          EFI_VARIABLE_RUNTIME_ACCESS,
 986                                          0, dummy);
 987                 }
 988
 989                 kfree(dummy);
 990
 991                 /*
 992                  * The runtime code may now have triggered a garbage collection
 993                  * run, so check the variable info again
 994                  */
 995                 status = efi.query_variable_info(attributes, &storage_size,
 996                                                  &remaining_size, &max_size);
 997
 998                 if (status != EFI_SUCCESS)
 999                         return status;
1000
1001                 /*
1002                  * There still isn't enough room, so return an error
1003                  */
1004                 if (remaining_size - size < EFI_MIN_RESERVE)
1005                         return EFI_OUT_OF_RESOURCES;
1006         }
1007
1008         return EFI_SUCCESS;
1009 }
1010 EXPORT_SYMBOL_GPL(efi_query_variable_store);