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 #include <linux/kernel.h>
  30 #include <linux/init.h>
  31 #include <linux/efi.h>
  32 #include <linux/export.h>
  33 #include <linux/bootmem.h>
  34 #include <linux/memblock.h>
  35 #include <linux/spinlock.h>
  36 #include <linux/uaccess.h>
  37 #include <linux/time.h>
  38 #include <linux/io.h>
  39 #include <linux/reboot.h>
  40 #include <linux/bcd.h>
  41
  42 #include <asm/setup.h>
  43 #include <asm/efi.h>
  44 #include <asm/time.h>
  45 #include <asm/cacheflush.h>
  46 #include <asm/tlbflush.h>
  47 #include <asm/x86_init.h>
  48
  49 #define EFI_DEBUG       1
  50 #define PFX             "EFI: "
  51
  52 int efi_enabled;
  53 EXPORT_SYMBOL(efi_enabled);
  54
  55 struct efi __read_mostly efi = {
  56         .mps        = EFI_INVALID_TABLE_ADDR,
  57         .acpi       = EFI_INVALID_TABLE_ADDR,
  58         .acpi20     = EFI_INVALID_TABLE_ADDR,
  59         .smbios     = EFI_INVALID_TABLE_ADDR,
  60         .sal_systab = EFI_INVALID_TABLE_ADDR,
  61         .boot_info  = EFI_INVALID_TABLE_ADDR,
  62         .hcdp       = EFI_INVALID_TABLE_ADDR,
  63         .uga        = EFI_INVALID_TABLE_ADDR,
  64         .uv_systab  = EFI_INVALID_TABLE_ADDR,
  65 };
  66 EXPORT_SYMBOL(efi);
  67
  68 struct efi_memory_map memmap;
  69
  70 static struct efi efi_phys __initdata;
  71 static efi_system_table_t efi_systab __initdata;
  72
  73 static int __init setup_noefi(char *arg)
  74 {
  75         efi_enabled = 0;
  76         return 0;
  77 }
  78 early_param("noefi", setup_noefi);
  79
  80 int add_efi_memmap;
  81 EXPORT_SYMBOL(add_efi_memmap);
  82
  83 static int __init setup_add_efi_memmap(char *arg)
  84 {
  85         add_efi_memmap = 1;
  86         return 0;
  87 }
  88 early_param("add_efi_memmap", setup_add_efi_memmap);
  89
  90
  91 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
  92 {
  93         unsigned long flags;
  94         efi_status_t status;
  95
  96         spin_lock_irqsave(&rtc_lock, flags);
  97         status = efi_call_virt2(get_time, tm, tc);
  98         spin_unlock_irqrestore(&rtc_lock, flags);
  99         return status;
 100 }
 101
 102 static efi_status_t virt_efi_set_time(efi_time_t *tm)
 103 {
 104         unsigned long flags;
 105         efi_status_t status;
 106
 107         spin_lock_irqsave(&rtc_lock, flags);
 108         status = efi_call_virt1(set_time, tm);
 109         spin_unlock_irqrestore(&rtc_lock, flags);
 110         return status;
 111 }
 112
 113 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
 114                                              efi_bool_t *pending,
 115                                              efi_time_t *tm)
 116 {
 117         unsigned long flags;
 118         efi_status_t status;
 119
 120         spin_lock_irqsave(&rtc_lock, flags);
 121         status = efi_call_virt3(get_wakeup_time,
 122                                 enabled, pending, tm);
 123         spin_unlock_irqrestore(&rtc_lock, flags);
 124         return status;
 125 }
 126
 127 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
 128 {
 129         unsigned long flags;
 130         efi_status_t status;
 131
 132         spin_lock_irqsave(&rtc_lock, flags);
 133         status = efi_call_virt2(set_wakeup_time,
 134                                 enabled, tm);
 135         spin_unlock_irqrestore(&rtc_lock, flags);
 136         return status;
 137 }
 138
 139 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
 140                                           efi_guid_t *vendor,
 141                                           u32 *attr,
 142                                           unsigned long *data_size,
 143                                           void *data)
 144 {
 145         return efi_call_virt5(get_variable,
 146                               name, vendor, attr,
 147                               data_size, data);
 148 }
 149
 150 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 151                                                efi_char16_t *name,
 152                                                efi_guid_t *vendor)
 153 {
 154         return efi_call_virt3(get_next_variable,
 155                               name_size, name, vendor);
 156 }
 157
 158 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 159                                           efi_guid_t *vendor,
 160                                           u32 attr,
 161                                           unsigned long data_size,
 162                                           void *data)
 163 {
 164         return efi_call_virt5(set_variable,
 165                               name, vendor, attr,
 166                               data_size, data);
 167 }
 168
 169 static efi_status_t virt_efi_query_variable_info(u32 attr,
 170                                                  u64 *storage_space,
 171                                                  u64 *remaining_space,
 172                                                  u64 *max_variable_size)
 173 {
 174         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 175                 return EFI_UNSUPPORTED;
 176
 177         return efi_call_virt4(query_variable_info, attr, storage_space,
 178                               remaining_space, max_variable_size);
 179 }
 180
 181 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 182 {
 183         return efi_call_virt1(get_next_high_mono_count, count);
 184 }
 185
 186 static void virt_efi_reset_system(int reset_type,
 187                                   efi_status_t status,
 188                                   unsigned long data_size,
 189                                   efi_char16_t *data)
 190 {
 191         efi_call_virt4(reset_system, reset_type, status,
 192                        data_size, data);
 193 }
 194
 195 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
 196                                             unsigned long count,
 197                                             unsigned long sg_list)
 198 {
 199         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 200                 return EFI_UNSUPPORTED;
 201
 202         return efi_call_virt3(update_capsule, capsules, count, sg_list);
 203 }
 204
 205 static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
 206                                                 unsigned long count,
 207                                                 u64 *max_size,
 208                                                 int *reset_type)
 209 {
 210         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 211                 return EFI_UNSUPPORTED;
 212
 213         return efi_call_virt4(query_capsule_caps, capsules, count, max_size,
 214                               reset_type);
 215 }
 216
 217 static efi_status_t __init phys_efi_set_virtual_address_map(
 218         unsigned long memory_map_size,
 219         unsigned long descriptor_size,
 220         u32 descriptor_version,
 221         efi_memory_desc_t *virtual_map)
 222 {
 223         efi_status_t status;
 224
 225         efi_call_phys_prelog();
 226         status = efi_call_phys4(efi_phys.set_virtual_address_map,
 227                                 memory_map_size, descriptor_size,
 228                                 descriptor_version, virtual_map);
 229         efi_call_phys_epilog();
 230         return status;
 231 }
 232
 233 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
 234                                              efi_time_cap_t *tc)
 235 {
 236         unsigned long flags;
 237         efi_status_t status;
 238
 239         spin_lock_irqsave(&rtc_lock, flags);
 240         efi_call_phys_prelog();
 241         status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
 242                                 virt_to_phys(tc));
 243         efi_call_phys_epilog();
 244         spin_unlock_irqrestore(&rtc_lock, flags);
 245         return status;
 246 }
 247
 248 int efi_set_rtc_mmss(unsigned long nowtime)
 249 {
 250         int real_seconds, real_minutes;
 251         efi_status_t    status;
 252         efi_time_t      eft;
 253         efi_time_cap_t  cap;
 254
 255         status = efi.get_time(&eft, &cap);
 256         if (status != EFI_SUCCESS) {
 257                 printk(KERN_ERR "Oops: efitime: can't read time!\n");
 258                 return -1;
 259         }
 260
 261         real_seconds = nowtime % 60;
 262         real_minutes = nowtime / 60;
 263         if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
 264                 real_minutes += 30;
 265         real_minutes %= 60;
 266         eft.minute = real_minutes;
 267         eft.second = real_seconds;
 268
 269         status = efi.set_time(&eft);
 270         if (status != EFI_SUCCESS) {
 271                 printk(KERN_ERR "Oops: efitime: can't write time!\n");
 272                 return -1;
 273         }
 274         return 0;
 275 }
 276
 277 unsigned long efi_get_time(void)
 278 {
 279         efi_status_t status;
 280         efi_time_t eft;
 281         efi_time_cap_t cap;
 282
 283         status = efi.get_time(&eft, &cap);
 284         if (status != EFI_SUCCESS)
 285                 printk(KERN_ERR "Oops: efitime: can't read time!\n");
 286
 287         return mktime(eft.year, eft.month, eft.day, eft.hour,
 288                       eft.minute, eft.second);
 289 }
 290
 291 /*
 292  * Tell the kernel about the EFI memory map.  This might include
 293  * more than the max 128 entries that can fit in the e820 legacy
 294  * (zeropage) memory map.
 295  */
 296
 297 static void __init do_add_efi_memmap(void)
 298 {
 299         void *p;
 300
 301         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 302                 efi_memory_desc_t *md = p;
 303                 unsigned long long start = md->phys_addr;
 304                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 305                 int e820_type;
 306
 307                 switch (md->type) {
 308                 case EFI_LOADER_CODE:
 309                 case EFI_LOADER_DATA:
 310                 case EFI_BOOT_SERVICES_CODE:
 311                 case EFI_BOOT_SERVICES_DATA:
 312                 case EFI_CONVENTIONAL_MEMORY:
 313                         if (md->attribute & EFI_MEMORY_WB)
 314                                 e820_type = E820_RAM;
 315                         else
 316                                 e820_type = E820_RESERVED;
 317                         break;
 318                 case EFI_ACPI_RECLAIM_MEMORY:
 319                         e820_type = E820_ACPI;
 320                         break;
 321                 case EFI_ACPI_MEMORY_NVS:
 322                         e820_type = E820_NVS;
 323                         break;
 324                 case EFI_UNUSABLE_MEMORY:
 325                         e820_type = E820_UNUSABLE;
 326                         break;
 327                 default:
 328                         /*
 329                          * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
 330                          * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
 331                          * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
 332                          */
 333                         e820_type = E820_RESERVED;
 334                         break;
 335                 }
 336                 e820_add_region(start, size, e820_type);
 337         }
 338         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 339 }
 340
 341 void __init efi_memblock_x86_reserve_range(void)
 342 {
 343         unsigned long pmap;
 344
 345 #ifdef CONFIG_X86_32
 346         pmap = boot_params.efi_info.efi_memmap;
 347 #else
 348         pmap = (boot_params.efi_info.efi_memmap |
 349                 ((__u64)boot_params.efi_info.efi_memmap_hi<<32));
 350 #endif
 351         memmap.phys_map = (void *)pmap;
 352         memmap.nr_map = boot_params.efi_info.efi_memmap_size /
 353                 boot_params.efi_info.efi_memdesc_size;
 354         memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
 355         memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
 356         memblock_reserve(pmap, memmap.nr_map * memmap.desc_size);
 357 }
 358
 359 #if EFI_DEBUG
 360 static void __init print_efi_memmap(void)
 361 {
 362         efi_memory_desc_t *md;
 363         void *p;
 364         int i;
 365
 366         for (p = memmap.map, i = 0;
 367              p < memmap.map_end;
 368              p += memmap.desc_size, i++) {
 369                 md = p;
 370                 printk(KERN_INFO PFX "mem%02u: type=%u, attr=0x%llx, "
 371                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 372                         i, md->type, md->attribute, md->phys_addr,
 373                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 374                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 375         }
 376 }
 377 #endif  /*  EFI_DEBUG  */
 378
 379 void __init efi_reserve_boot_services(void)
 380 {
 381         void *p;
 382
 383         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 384                 efi_memory_desc_t *md = p;
 385                 u64 start = md->phys_addr;
 386                 u64 size = md->num_pages << EFI_PAGE_SHIFT;
 387
 388                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 389                     md->type != EFI_BOOT_SERVICES_DATA)
 390                         continue;
 391                 /* Only reserve where possible:
 392                  * - Not within any already allocated areas
 393                  * - Not over any memory area (really needed, if above?)
 394                  * - Not within any part of the kernel
 395                  * - Not the bios reserved area
 396                 */
 397                 if ((start+size >= virt_to_phys(_text)
 398                                 && start <= virt_to_phys(_end)) ||
 399                         !e820_all_mapped(start, start+size, E820_RAM) ||
 400                         memblock_is_region_reserved(start, size)) {
 401                         /* Could not reserve, skip it */
 402                         md->num_pages = 0;
 403                         memblock_dbg(PFX "Could not reserve boot range "
 404                                         "[0x%010llx-0x%010llx]\n",
 405                                                 start, start+size-1);
 406                 } else
 407                         memblock_reserve(start, size);
 408         }
 409 }
 410
 411 static void __init efi_free_boot_services(void)
 412 {
 413         void *p;
 414
 415         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 416                 efi_memory_desc_t *md = p;
 417                 unsigned long long start = md->phys_addr;
 418                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 419
 420                 if (md->type != EFI_BOOT_SERVICES_CODE &&
 421                     md->type != EFI_BOOT_SERVICES_DATA)
 422                         continue;
 423
 424                 /* Could not reserve boot area */
 425                 if (!size)
 426                         continue;
 427
 428                 free_bootmem_late(start, size);
 429         }
 430 }
 431
 432 void __init efi_init(void)
 433 {
 434         efi_config_table_t *config_tables;
 435         efi_runtime_services_t *runtime;
 436         efi_char16_t *c16;
 437         char vendor[100] = "unknown";
 438         int i = 0;
 439         void *tmp;
 440
 441 #ifdef CONFIG_X86_32
 442         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 443 #else
 444         efi_phys.systab = (efi_system_table_t *)
 445                 (boot_params.efi_info.efi_systab |
 446                  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 447 #endif
 448
 449         efi.systab = early_ioremap((unsigned long)efi_phys.systab,
 450                                    sizeof(efi_system_table_t));
 451         if (efi.systab == NULL)
 452                 printk(KERN_ERR "Couldn't map the EFI system table!\n");
 453         memcpy(&efi_systab, efi.systab, sizeof(efi_system_table_t));
 454         early_iounmap(efi.systab, sizeof(efi_system_table_t));
 455         efi.systab = &efi_systab;
 456
 457         /*
 458          * Verify the EFI Table
 459          */
 460         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
 461                 printk(KERN_ERR "EFI system table signature incorrect!\n");
 462         if ((efi.systab->hdr.revision >> 16) == 0)
 463                 printk(KERN_ERR "Warning: EFI system table version "
 464                        "%d.%02d, expected 1.00 or greater!\n",
 465                        efi.systab->hdr.revision >> 16,
 466                        efi.systab->hdr.revision & 0xffff);
 467
 468         /*
 469          * Show what we know for posterity
 470          */
 471         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 472         if (c16) {
 473                 for (i = 0; i < sizeof(vendor) - 1 && *c16; ++i)
 474                         vendor[i] = *c16++;
 475                 vendor[i] = '\0';
 476         } else
 477                 printk(KERN_ERR PFX "Could not map the firmware vendor!\n");
 478         early_iounmap(tmp, 2);
 479
 480         printk(KERN_INFO "EFI v%u.%.02u by %s\n",
 481                efi.systab->hdr.revision >> 16,
 482                efi.systab->hdr.revision & 0xffff, vendor);
 483
 484         /*
 485          * Let's see what config tables the firmware passed to us.
 486          */
 487         config_tables = early_ioremap(
 488                 efi.systab->tables,
 489                 efi.systab->nr_tables * sizeof(efi_config_table_t));
 490         if (config_tables == NULL)
 491                 printk(KERN_ERR "Could not map EFI Configuration Table!\n");
 492
 493         printk(KERN_INFO);
 494         for (i = 0; i < efi.systab->nr_tables; i++) {
 495                 if (!efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID)) {
 496                         efi.mps = config_tables[i].table;
 497                         printk(" MPS=0x%lx ", config_tables[i].table);
 498                 } else if (!efi_guidcmp(config_tables[i].guid,
 499                                         ACPI_20_TABLE_GUID)) {
 500                         efi.acpi20 = config_tables[i].table;
 501                         printk(" ACPI 2.0=0x%lx ", config_tables[i].table);
 502                 } else if (!efi_guidcmp(config_tables[i].guid,
 503                                         ACPI_TABLE_GUID)) {
 504                         efi.acpi = config_tables[i].table;
 505                         printk(" ACPI=0x%lx ", config_tables[i].table);
 506                 } else if (!efi_guidcmp(config_tables[i].guid,
 507                                         SMBIOS_TABLE_GUID)) {
 508                         efi.smbios = config_tables[i].table;
 509                         printk(" SMBIOS=0x%lx ", config_tables[i].table);
 510 #ifdef CONFIG_X86_UV
 511                 } else if (!efi_guidcmp(config_tables[i].guid,
 512                                         UV_SYSTEM_TABLE_GUID)) {
 513                         efi.uv_systab = config_tables[i].table;
 514                         printk(" UVsystab=0x%lx ", config_tables[i].table);
 515 #endif
 516                 } else if (!efi_guidcmp(config_tables[i].guid,
 517                                         HCDP_TABLE_GUID)) {
 518                         efi.hcdp = config_tables[i].table;
 519                         printk(" HCDP=0x%lx ", config_tables[i].table);
 520                 } else if (!efi_guidcmp(config_tables[i].guid,
 521                                         UGA_IO_PROTOCOL_GUID)) {
 522                         efi.uga = config_tables[i].table;
 523                         printk(" UGA=0x%lx ", config_tables[i].table);
 524                 }
 525         }
 526         printk("\n");
 527         early_iounmap(config_tables,
 528                           efi.systab->nr_tables * sizeof(efi_config_table_t));
 529
 530         /*
 531          * Check out the runtime services table. We need to map
 532          * the runtime services table so that we can grab the physical
 533          * address of several of the EFI runtime functions, needed to
 534          * set the firmware into virtual mode.
 535          */
 536         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 537                                 sizeof(efi_runtime_services_t));
 538         if (runtime != NULL) {
 539                 /*
 540                  * We will only need *early* access to the following
 541                  * two EFI runtime services before set_virtual_address_map
 542                  * is invoked.
 543                  */
 544                 efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 545                 efi_phys.set_virtual_address_map =
 546                         (efi_set_virtual_address_map_t *)
 547                         runtime->set_virtual_address_map;
 548                 /*
 549                  * Make efi_get_time can be called before entering
 550                  * virtual mode.
 551                  */
 552                 efi.get_time = phys_efi_get_time;
 553         } else
 554                 printk(KERN_ERR "Could not map the EFI runtime service "
 555                        "table!\n");
 556         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 557
 558         /* Map the EFI memory map */
 559         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 560                                    memmap.nr_map * memmap.desc_size);
 561         if (memmap.map == NULL)
 562                 printk(KERN_ERR "Could not map the EFI memory map!\n");
 563         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 564
 565         if (memmap.desc_size != sizeof(efi_memory_desc_t))
 566                 printk(KERN_WARNING
 567                   "Kernel-defined memdesc doesn't match the one from EFI!\n");
 568
 569         if (add_efi_memmap)
 570                 do_add_efi_memmap();
 571
 572 #ifdef CONFIG_X86_32
 573         x86_platform.get_wallclock = efi_get_time;
 574         x86_platform.set_wallclock = efi_set_rtc_mmss;
 575 #endif
 576
 577 #if EFI_DEBUG
 578         print_efi_memmap();
 579 #endif
 580 }
 581
 582 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 583 {
 584         u64 addr, npages;
 585
 586         addr = md->virt_addr;
 587         npages = md->num_pages;
 588
 589         memrange_efi_to_native(&addr, &npages);
 590
 591         if (executable)
 592                 set_memory_x(addr, npages);
 593         else
 594                 set_memory_nx(addr, npages);
 595 }
 596
 597 static void __init runtime_code_page_mkexec(void)
 598 {
 599         efi_memory_desc_t *md;
 600         void *p;
 601
 602         /* Make EFI runtime service code area executable */
 603         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 604                 md = p;
 605
 606                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 607                         continue;
 608
 609                 efi_set_executable(md, true);
 610         }
 611 }
 612
 613 /*
 614  * This function will switch the EFI runtime services to virtual mode.
 615  * Essentially, look through the EFI memmap and map every region that
 616  * has the runtime attribute bit set in its memory descriptor and update
 617  * that memory descriptor with the virtual address obtained from ioremap().
 618  * This enables the runtime services to be called without having to
 619  * thunk back into physical mode for every invocation.
 620  */
 621 void __init efi_enter_virtual_mode(void)
 622 {
 623         efi_memory_desc_t *md, *prev_md = NULL;
 624         efi_status_t status;
 625         unsigned long size;
 626         u64 end, systab, addr, npages, end_pfn;
 627         void *p, *va, *new_memmap = NULL;
 628         int count = 0;
 629
 630         efi.systab = NULL;
 631
 632         /* Merge contiguous regions of the same type and attribute */
 633         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 634                 u64 prev_size;
 635                 md = p;
 636
 637                 if (!prev_md) {
 638                         prev_md = md;
 639                         continue;
 640                 }
 641
 642                 if (prev_md->type != md->type ||
 643                     prev_md->attribute != md->attribute) {
 644                         prev_md = md;
 645                         continue;
 646                 }
 647
 648                 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
 649
 650                 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
 651                         prev_md->num_pages += md->num_pages;
 652                         md->type = EFI_RESERVED_TYPE;
 653                         md->attribute = 0;
 654                         continue;
 655                 }
 656                 prev_md = md;
 657         }
 658
 659         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 660                 md = p;
 661                 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
 662                     md->type != EFI_BOOT_SERVICES_CODE &&
 663                     md->type != EFI_BOOT_SERVICES_DATA)
 664                         continue;
 665
 666                 size = md->num_pages << EFI_PAGE_SHIFT;
 667                 end = md->phys_addr + size;
 668
 669                 end_pfn = PFN_UP(end);
 670                 if (end_pfn <= max_low_pfn_mapped
 671                     || (end_pfn > (1UL << (32 - PAGE_SHIFT))
 672                         && end_pfn <= max_pfn_mapped))
 673                         va = __va(md->phys_addr);
 674                 else
 675                         va = efi_ioremap(md->phys_addr, size, md->type);
 676
 677                 md->virt_addr = (u64) (unsigned long) va;
 678
 679                 if (!va) {
 680                         printk(KERN_ERR PFX "ioremap of 0x%llX failed!\n",
 681                                (unsigned long long)md->phys_addr);
 682                         continue;
 683                 }
 684
 685                 if (!(md->attribute & EFI_MEMORY_WB)) {
 686                         addr = md->virt_addr;
 687                         npages = md->num_pages;
 688                         memrange_efi_to_native(&addr, &npages);
 689                         set_memory_uc(addr, npages);
 690                 }
 691
 692                 systab = (u64) (unsigned long) efi_phys.systab;
 693                 if (md->phys_addr <= systab && systab < end) {
 694                         systab += md->virt_addr - md->phys_addr;
 695                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
 696                 }
 697                 new_memmap = krealloc(new_memmap,
 698                                       (count + 1) * memmap.desc_size,
 699                                       GFP_KERNEL);
 700                 memcpy(new_memmap + (count * memmap.desc_size), md,
 701                        memmap.desc_size);
 702                 count++;
 703         }
 704
 705         BUG_ON(!efi.systab);
 706
 707         status = phys_efi_set_virtual_address_map(
 708                 memmap.desc_size * count,
 709                 memmap.desc_size,
 710                 memmap.desc_version,
 711                 (efi_memory_desc_t *)__pa(new_memmap));
 712
 713         if (status != EFI_SUCCESS) {
 714                 printk(KERN_ALERT "Unable to switch EFI into virtual mode "
 715                        "(status=%lx)!\n", status);
 716                 panic("EFI call to SetVirtualAddressMap() failed!");
 717         }
 718
 719         /*
 720          * Thankfully, it does seem that no runtime services other than
 721          * SetVirtualAddressMap() will touch boot services code, so we can
 722          * get rid of it all at this point
 723          */
 724         efi_free_boot_services();
 725
 726         /*
 727          * Now that EFI is in virtual mode, update the function
 728          * pointers in the runtime service table to the new virtual addresses.
 729          *
 730          * Call EFI services through wrapper functions.
 731          */
 732         efi.get_time = virt_efi_get_time;
 733         efi.set_time = virt_efi_set_time;
 734         efi.get_wakeup_time = virt_efi_get_wakeup_time;
 735         efi.set_wakeup_time = virt_efi_set_wakeup_time;
 736         efi.get_variable = virt_efi_get_variable;
 737         efi.get_next_variable = virt_efi_get_next_variable;
 738         efi.set_variable = virt_efi_set_variable;
 739         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
 740         efi.reset_system = virt_efi_reset_system;
 741         efi.set_virtual_address_map = NULL;
 742         efi.query_variable_info = virt_efi_query_variable_info;
 743         efi.update_capsule = virt_efi_update_capsule;
 744         efi.query_capsule_caps = virt_efi_query_capsule_caps;
 745         if (__supported_pte_mask & _PAGE_NX)
 746                 runtime_code_page_mkexec();
 747         early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 748         memmap.map = NULL;
 749         kfree(new_memmap);
 750 }
 751
 752 /*
 753  * Convenience functions to obtain memory types and attributes
 754  */
 755 u32 efi_mem_type(unsigned long phys_addr)
 756 {
 757         efi_memory_desc_t *md;
 758         void *p;
 759
 760         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 761                 md = p;
 762                 if ((md->phys_addr <= phys_addr) &&
 763                     (phys_addr < (md->phys_addr +
 764                                   (md->num_pages << EFI_PAGE_SHIFT))))
 765                         return md->type;
 766         }
 767         return 0;
 768 }
 769
 770 u64 efi_mem_attributes(unsigned long phys_addr)
 771 {
 772         efi_memory_desc_t *md;
 773         void *p;
 774
 775         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 776                 md = p;
 777                 if ((md->phys_addr <= phys_addr) &&
 778                     (phys_addr < (md->phys_addr +
 779                                   (md->num_pages << EFI_PAGE_SHIFT))))
 780                         return md->attribute;
 781         }
 782         return 0;
 783 }