arch/x86/kernel/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/bootmem.h>
  33 #include <linux/spinlock.h>
  34 #include <linux/uaccess.h>
  35 #include <linux/time.h>
  36 #include <linux/io.h>
  37 #include <linux/reboot.h>
  38 #include <linux/bcd.h>
  39
  40 #include <asm/setup.h>
  41 #include <asm/efi.h>
  42 #include <asm/time.h>
  43 #include <asm/cacheflush.h>
  44 #include <asm/tlbflush.h>
  45
  46 #define EFI_DEBUG       1
  47 #define PFX             "EFI: "
  48
  49 int efi_enabled;
  50 EXPORT_SYMBOL(efi_enabled);
  51
  52 struct efi efi;
  53 EXPORT_SYMBOL(efi);
  54
  55 struct efi_memory_map memmap;
  56
  57 static struct efi efi_phys __initdata;
  58 static efi_system_table_t efi_systab __initdata;
  59
  60 static int __init setup_noefi(char *arg)
  61 {
  62         efi_enabled = 0;
  63         return 0;
  64 }
  65 early_param("noefi", setup_noefi);
  66
  67 int add_efi_memmap;
  68 EXPORT_SYMBOL(add_efi_memmap);
  69
  70 static int __init setup_add_efi_memmap(char *arg)
  71 {
  72         add_efi_memmap = 1;
  73         return 0;
  74 }
  75 early_param("add_efi_memmap", setup_add_efi_memmap);
  76
  77
  78 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
  79 {
  80         return efi_call_virt2(get_time, tm, tc);
  81 }
  82
  83 static efi_status_t virt_efi_set_time(efi_time_t *tm)
  84 {
  85         return efi_call_virt1(set_time, tm);
  86 }
  87
  88 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
  89                                              efi_bool_t *pending,
  90                                              efi_time_t *tm)
  91 {
  92         return efi_call_virt3(get_wakeup_time,
  93                               enabled, pending, tm);
  94 }
  95
  96 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
  97 {
  98         return efi_call_virt2(set_wakeup_time,
  99                               enabled, tm);
 100 }
 101
 102 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
 103                                           efi_guid_t *vendor,
 104                                           u32 *attr,
 105                                           unsigned long *data_size,
 106                                           void *data)
 107 {
 108         return efi_call_virt5(get_variable,
 109                               name, vendor, attr,
 110                               data_size, data);
 111 }
 112
 113 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 114                                                efi_char16_t *name,
 115                                                efi_guid_t *vendor)
 116 {
 117         return efi_call_virt3(get_next_variable,
 118                               name_size, name, vendor);
 119 }
 120
 121 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 122                                           efi_guid_t *vendor,
 123                                           unsigned long attr,
 124                                           unsigned long data_size,
 125                                           void *data)
 126 {
 127         return efi_call_virt5(set_variable,
 128                               name, vendor, attr,
 129                               data_size, data);
 130 }
 131
 132 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 133 {
 134         return efi_call_virt1(get_next_high_mono_count, count);
 135 }
 136
 137 static void virt_efi_reset_system(int reset_type,
 138                                   efi_status_t status,
 139                                   unsigned long data_size,
 140                                   efi_char16_t *data)
 141 {
 142         efi_call_virt4(reset_system, reset_type, status,
 143                        data_size, data);
 144 }
 145
 146 static efi_status_t virt_efi_set_virtual_address_map(
 147         unsigned long memory_map_size,
 148         unsigned long descriptor_size,
 149         u32 descriptor_version,
 150         efi_memory_desc_t *virtual_map)
 151 {
 152         return efi_call_virt4(set_virtual_address_map,
 153                               memory_map_size, descriptor_size,
 154                               descriptor_version, virtual_map);
 155 }
 156
 157 static efi_status_t __init phys_efi_set_virtual_address_map(
 158         unsigned long memory_map_size,
 159         unsigned long descriptor_size,
 160         u32 descriptor_version,
 161         efi_memory_desc_t *virtual_map)
 162 {
 163         efi_status_t status;
 164
 165         efi_call_phys_prelog();
 166         status = efi_call_phys4(efi_phys.set_virtual_address_map,
 167                                 memory_map_size, descriptor_size,
 168                                 descriptor_version, virtual_map);
 169         efi_call_phys_epilog();
 170         return status;
 171 }
 172
 173 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
 174                                              efi_time_cap_t *tc)
 175 {
 176         efi_status_t status;
 177
 178         efi_call_phys_prelog();
 179         status = efi_call_phys2(efi_phys.get_time, tm, tc);
 180         efi_call_phys_epilog();
 181         return status;
 182 }
 183
 184 int efi_set_rtc_mmss(unsigned long nowtime)
 185 {
 186         int real_seconds, real_minutes;
 187         efi_status_t    status;
 188         efi_time_t      eft;
 189         efi_time_cap_t  cap;
 190
 191         status = efi.get_time(&eft, &cap);
 192         if (status != EFI_SUCCESS) {
 193                 printk(KERN_ERR "Oops: efitime: can't read time!\n");
 194                 return -1;
 195         }
 196
 197         real_seconds = nowtime % 60;
 198         real_minutes = nowtime / 60;
 199         if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
 200                 real_minutes += 30;
 201         real_minutes %= 60;
 202         eft.minute = real_minutes;
 203         eft.second = real_seconds;
 204
 205         status = efi.set_time(&eft);
 206         if (status != EFI_SUCCESS) {
 207                 printk(KERN_ERR "Oops: efitime: can't write time!\n");
 208                 return -1;
 209         }
 210         return 0;
 211 }
 212
 213 unsigned long efi_get_time(void)
 214 {
 215         efi_status_t status;
 216         efi_time_t eft;
 217         efi_time_cap_t cap;
 218
 219         status = efi.get_time(&eft, &cap);
 220         if (status != EFI_SUCCESS)
 221                 printk(KERN_ERR "Oops: efitime: can't read time!\n");
 222
 223         return mktime(eft.year, eft.month, eft.day, eft.hour,
 224                       eft.minute, eft.second);
 225 }
 226
 227 /*
 228  * Tell the kernel about the EFI memory map.  This might include
 229  * more than the max 128 entries that can fit in the e820 legacy
 230  * (zeropage) memory map.
 231  */
 232
 233 static void __init do_add_efi_memmap(void)
 234 {
 235         void *p;
 236
 237         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 238                 efi_memory_desc_t *md = p;
 239                 unsigned long long start = md->phys_addr;
 240                 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
 241                 int e820_type;
 242
 243                 if (md->attribute & EFI_MEMORY_WB)
 244                         e820_type = E820_RAM;
 245                 else
 246                         e820_type = E820_RESERVED;
 247                 e820_add_region(start, size, e820_type);
 248         }
 249         sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 250 }
 251
 252 void __init efi_reserve_early(void)
 253 {
 254         unsigned long pmap;
 255
 256 #ifdef CONFIG_X86_32
 257         pmap = boot_params.efi_info.efi_memmap;
 258 #else
 259         pmap = (boot_params.efi_info.efi_memmap |
 260                 ((__u64)boot_params.efi_info.efi_memmap_hi<<32));
 261 #endif
 262         memmap.phys_map = (void *)pmap;
 263         memmap.nr_map = boot_params.efi_info.efi_memmap_size /
 264                 boot_params.efi_info.efi_memdesc_size;
 265         memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
 266         memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
 267         reserve_early(pmap, pmap + memmap.nr_map * memmap.desc_size,
 268                       "EFI memmap");
 269 }
 270
 271 #if EFI_DEBUG
 272 static void __init print_efi_memmap(void)
 273 {
 274         efi_memory_desc_t *md;
 275         void *p;
 276         int i;
 277
 278         for (p = memmap.map, i = 0;
 279              p < memmap.map_end;
 280              p += memmap.desc_size, i++) {
 281                 md = p;
 282                 printk(KERN_INFO PFX "mem%02u: type=%u, attr=0x%llx, "
 283                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 284                         i, md->type, md->attribute, md->phys_addr,
 285                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 286                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 287         }
 288 }
 289 #endif  /*  EFI_DEBUG  */
 290
 291 void __init efi_init(void)
 292 {
 293         efi_config_table_t *config_tables;
 294         efi_runtime_services_t *runtime;
 295         efi_char16_t *c16;
 296         char vendor[100] = "unknown";
 297         int i = 0;
 298         void *tmp;
 299
 300 #ifdef CONFIG_X86_32
 301         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 302 #else
 303         efi_phys.systab = (efi_system_table_t *)
 304                 (boot_params.efi_info.efi_systab |
 305                  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 306 #endif
 307
 308         efi.systab = early_ioremap((unsigned long)efi_phys.systab,
 309                                    sizeof(efi_system_table_t));
 310         if (efi.systab == NULL)
 311                 printk(KERN_ERR "Couldn't map the EFI system table!\n");
 312         memcpy(&efi_systab, efi.systab, sizeof(efi_system_table_t));
 313         early_iounmap(efi.systab, sizeof(efi_system_table_t));
 314         efi.systab = &efi_systab;
 315
 316         /*
 317          * Verify the EFI Table
 318          */
 319         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
 320                 printk(KERN_ERR "EFI system table signature incorrect!\n");
 321         if ((efi.systab->hdr.revision >> 16) == 0)
 322                 printk(KERN_ERR "Warning: EFI system table version "
 323                        "%d.%02d, expected 1.00 or greater!\n",
 324                        efi.systab->hdr.revision >> 16,
 325                        efi.systab->hdr.revision & 0xffff);
 326
 327         /*
 328          * Show what we know for posterity
 329          */
 330         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 331         if (c16) {
 332                 for (i = 0; i < sizeof(vendor) && *c16; ++i)
 333                         vendor[i] = *c16++;
 334                 vendor[i] = '\0';
 335         } else
 336                 printk(KERN_ERR PFX "Could not map the firmware vendor!\n");
 337         early_iounmap(tmp, 2);
 338
 339         printk(KERN_INFO "EFI v%u.%.02u by %s \n",
 340                efi.systab->hdr.revision >> 16,
 341                efi.systab->hdr.revision & 0xffff, vendor);
 342
 343         /*
 344          * Let's see what config tables the firmware passed to us.
 345          */
 346         config_tables = early_ioremap(
 347                 efi.systab->tables,
 348                 efi.systab->nr_tables * sizeof(efi_config_table_t));
 349         if (config_tables == NULL)
 350                 printk(KERN_ERR "Could not map EFI Configuration Table!\n");
 351
 352         printk(KERN_INFO);
 353         for (i = 0; i < efi.systab->nr_tables; i++) {
 354                 if (!efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID)) {
 355                         efi.mps = config_tables[i].table;
 356                         printk(" MPS=0x%lx ", config_tables[i].table);
 357                 } else if (!efi_guidcmp(config_tables[i].guid,
 358                                         ACPI_20_TABLE_GUID)) {
 359                         efi.acpi20 = config_tables[i].table;
 360                         printk(" ACPI 2.0=0x%lx ", config_tables[i].table);
 361                 } else if (!efi_guidcmp(config_tables[i].guid,
 362                                         ACPI_TABLE_GUID)) {
 363                         efi.acpi = config_tables[i].table;
 364                         printk(" ACPI=0x%lx ", config_tables[i].table);
 365                 } else if (!efi_guidcmp(config_tables[i].guid,
 366                                         SMBIOS_TABLE_GUID)) {
 367                         efi.smbios = config_tables[i].table;
 368                         printk(" SMBIOS=0x%lx ", config_tables[i].table);
 369                 } else if (!efi_guidcmp(config_tables[i].guid,
 370                                         UV_SYSTEM_TABLE_GUID)) {
 371                         efi.uv_systab = config_tables[i].table;
 372                         printk(" UVsystab=0x%lx ", config_tables[i].table);
 373                 } else if (!efi_guidcmp(config_tables[i].guid,
 374                                         HCDP_TABLE_GUID)) {
 375                         efi.hcdp = config_tables[i].table;
 376                         printk(" HCDP=0x%lx ", config_tables[i].table);
 377                 } else if (!efi_guidcmp(config_tables[i].guid,
 378                                         UGA_IO_PROTOCOL_GUID)) {
 379                         efi.uga = config_tables[i].table;
 380                         printk(" UGA=0x%lx ", config_tables[i].table);
 381                 }
 382         }
 383         printk("\n");
 384         early_iounmap(config_tables,
 385                           efi.systab->nr_tables * sizeof(efi_config_table_t));
 386
 387         /*
 388          * Check out the runtime services table. We need to map
 389          * the runtime services table so that we can grab the physical
 390          * address of several of the EFI runtime functions, needed to
 391          * set the firmware into virtual mode.
 392          */
 393         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 394                                 sizeof(efi_runtime_services_t));
 395         if (runtime != NULL) {
 396                 /*
 397                  * We will only need *early* access to the following
 398                  * two EFI runtime services before set_virtual_address_map
 399                  * is invoked.
 400                  */
 401                 efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 402                 efi_phys.set_virtual_address_map =
 403                         (efi_set_virtual_address_map_t *)
 404                         runtime->set_virtual_address_map;
 405                 /*
 406                  * Make efi_get_time can be called before entering
 407                  * virtual mode.
 408                  */
 409                 efi.get_time = phys_efi_get_time;
 410         } else
 411                 printk(KERN_ERR "Could not map the EFI runtime service "
 412                        "table!\n");
 413         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 414
 415         /* Map the EFI memory map */
 416         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 417                                    memmap.nr_map * memmap.desc_size);
 418         if (memmap.map == NULL)
 419                 printk(KERN_ERR "Could not map the EFI memory map!\n");
 420         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 421
 422         if (memmap.desc_size != sizeof(efi_memory_desc_t))
 423                 printk(KERN_WARNING
 424                   "Kernel-defined memdesc doesn't match the one from EFI!\n");
 425
 426         if (add_efi_memmap)
 427                 do_add_efi_memmap();
 428
 429         /* Setup for EFI runtime service */
 430         reboot_type = BOOT_EFI;
 431
 432 #if EFI_DEBUG
 433         print_efi_memmap();
 434 #endif
 435 }
 436
 437 static void __init runtime_code_page_mkexec(void)
 438 {
 439         efi_memory_desc_t *md;
 440         void *p;
 441         u64 addr, npages;
 442
 443         /* Make EFI runtime service code area executable */
 444         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 445                 md = p;
 446
 447                 if (md->type != EFI_RUNTIME_SERVICES_CODE)
 448                         continue;
 449
 450                 addr = md->virt_addr;
 451                 npages = md->num_pages;
 452                 memrange_efi_to_native(&addr, &npages);
 453                 set_memory_x(addr, npages);
 454         }
 455 }
 456
 457 /*
 458  * This function will switch the EFI runtime services to virtual mode.
 459  * Essentially, look through the EFI memmap and map every region that
 460  * has the runtime attribute bit set in its memory descriptor and update
 461  * that memory descriptor with the virtual address obtained from ioremap().
 462  * This enables the runtime services to be called without having to
 463  * thunk back into physical mode for every invocation.
 464  */
 465 void __init efi_enter_virtual_mode(void)
 466 {
 467         efi_memory_desc_t *md;
 468         efi_status_t status;
 469         unsigned long size;
 470         u64 end, systab, addr, npages;
 471         void *p, *va;
 472
 473         efi.systab = NULL;
 474         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 475                 md = p;
 476                 if (!(md->attribute & EFI_MEMORY_RUNTIME))
 477                         continue;
 478
 479                 size = md->num_pages << EFI_PAGE_SHIFT;
 480                 end = md->phys_addr + size;
 481
 482                 if (PFN_UP(end) <= max_low_pfn_mapped)
 483                         va = __va(md->phys_addr);
 484                 else
 485                         va = efi_ioremap(md->phys_addr, size);
 486
 487                 md->virt_addr = (u64) (unsigned long) va;
 488
 489                 if (!va) {
 490                         printk(KERN_ERR PFX "ioremap of 0x%llX failed!\n",
 491                                (unsigned long long)md->phys_addr);
 492                         continue;
 493                 }
 494
 495                 if (!(md->attribute & EFI_MEMORY_WB)) {
 496                         addr = md->virt_addr;
 497                         npages = md->num_pages;
 498                         memrange_efi_to_native(&addr, &npages);
 499                         set_memory_uc(addr, npages);
 500                 }
 501
 502                 systab = (u64) (unsigned long) efi_phys.systab;
 503                 if (md->phys_addr <= systab && systab < end) {
 504                         systab += md->virt_addr - md->phys_addr;
 505                         efi.systab = (efi_system_table_t *) (unsigned long) systab;
 506                 }
 507         }
 508
 509         BUG_ON(!efi.systab);
 510
 511         status = phys_efi_set_virtual_address_map(
 512                 memmap.desc_size * memmap.nr_map,
 513                 memmap.desc_size,
 514                 memmap.desc_version,
 515                 memmap.phys_map);
 516
 517         if (status != EFI_SUCCESS) {
 518                 printk(KERN_ALERT "Unable to switch EFI into virtual mode "
 519                        "(status=%lx)!\n", status);
 520                 panic("EFI call to SetVirtualAddressMap() failed!");
 521         }
 522
 523         /*
 524          * Now that EFI is in virtual mode, update the function
 525          * pointers in the runtime service table to the new virtual addresses.
 526          *
 527          * Call EFI services through wrapper functions.
 528          */
 529         efi.get_time = virt_efi_get_time;
 530         efi.set_time = virt_efi_set_time;
 531         efi.get_wakeup_time = virt_efi_get_wakeup_time;
 532         efi.set_wakeup_time = virt_efi_set_wakeup_time;
 533         efi.get_variable = virt_efi_get_variable;
 534         efi.get_next_variable = virt_efi_get_next_variable;
 535         efi.set_variable = virt_efi_set_variable;
 536         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
 537         efi.reset_system = virt_efi_reset_system;
 538         efi.set_virtual_address_map = virt_efi_set_virtual_address_map;
 539         if (__supported_pte_mask & _PAGE_NX)
 540                 runtime_code_page_mkexec();
 541         early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
 542         memmap.map = NULL;
 543 }
 544
 545 /*
 546  * Convenience functions to obtain memory types and attributes
 547  */
 548 u32 efi_mem_type(unsigned long phys_addr)
 549 {
 550         efi_memory_desc_t *md;
 551         void *p;
 552
 553         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 554                 md = p;
 555                 if ((md->phys_addr <= phys_addr) &&
 556                     (phys_addr < (md->phys_addr +
 557                                   (md->num_pages << EFI_PAGE_SHIFT))))
 558                         return md->type;
 559         }
 560         return 0;
 561 }
 562
 563 u64 efi_mem_attributes(unsigned long phys_addr)
 564 {
 565         efi_memory_desc_t *md;
 566         void *p;
 567
 568         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 569                 md = p;
 570                 if ((md->phys_addr <= phys_addr) &&
 571                     (phys_addr < (md->phys_addr +
 572                                   (md->num_pages << EFI_PAGE_SHIFT))))
 573                         return md->attribute;
 574         }
 575         return 0;
 576 }