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 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 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
  68 {
  69         return efi_call_virt2(get_time, tm, tc);
  70 }
  71
  72 static efi_status_t virt_efi_set_time(efi_time_t *tm)
  73 {
  74         return efi_call_virt1(set_time, tm);
  75 }
  76
  77 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
  78                                              efi_bool_t *pending,
  79                                              efi_time_t *tm)
  80 {
  81         return efi_call_virt3(get_wakeup_time,
  82                               enabled, pending, tm);
  83 }
  84
  85 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
  86 {
  87         return efi_call_virt2(set_wakeup_time,
  88                               enabled, tm);
  89 }
  90
  91 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
  92                                           efi_guid_t *vendor,
  93                                           u32 *attr,
  94                                           unsigned long *data_size,
  95                                           void *data)
  96 {
  97         return efi_call_virt5(get_variable,
  98                               name, vendor, attr,
  99                               data_size, data);
 100 }
 101
 102 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 103                                                efi_char16_t *name,
 104                                                efi_guid_t *vendor)
 105 {
 106         return efi_call_virt3(get_next_variable,
 107                               name_size, name, vendor);
 108 }
 109
 110 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 111                                           efi_guid_t *vendor,
 112                                           unsigned long attr,
 113                                           unsigned long data_size,
 114                                           void *data)
 115 {
 116         return efi_call_virt5(set_variable,
 117                               name, vendor, attr,
 118                               data_size, data);
 119 }
 120
 121 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 122 {
 123         return efi_call_virt1(get_next_high_mono_count, count);
 124 }
 125
 126 static void virt_efi_reset_system(int reset_type,
 127                                   efi_status_t status,
 128                                   unsigned long data_size,
 129                                   efi_char16_t *data)
 130 {
 131         efi_call_virt4(reset_system, reset_type, status,
 132                        data_size, data);
 133 }
 134
 135 static efi_status_t virt_efi_set_virtual_address_map(
 136         unsigned long memory_map_size,
 137         unsigned long descriptor_size,
 138         u32 descriptor_version,
 139         efi_memory_desc_t *virtual_map)
 140 {
 141         return efi_call_virt4(set_virtual_address_map,
 142                               memory_map_size, descriptor_size,
 143                               descriptor_version, virtual_map);
 144 }
 145
 146 static efi_status_t __init phys_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         efi_status_t status;
 153
 154         efi_call_phys_prelog();
 155         status = efi_call_phys4(efi_phys.set_virtual_address_map,
 156                                 memory_map_size, descriptor_size,
 157                                 descriptor_version, virtual_map);
 158         efi_call_phys_epilog();
 159         return status;
 160 }
 161
 162 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
 163                                              efi_time_cap_t *tc)
 164 {
 165         efi_status_t status;
 166
 167         efi_call_phys_prelog();
 168         status = efi_call_phys2(efi_phys.get_time, tm, tc);
 169         efi_call_phys_epilog();
 170         return status;
 171 }
 172
 173 int efi_set_rtc_mmss(unsigned long nowtime)
 174 {
 175         int real_seconds, real_minutes;
 176         efi_status_t    status;
 177         efi_time_t      eft;
 178         efi_time_cap_t  cap;
 179
 180         status = efi.get_time(&eft, &cap);
 181         if (status != EFI_SUCCESS) {
 182                 printk(KERN_ERR "Oops: efitime: can't read time!\n");
 183                 return -1;
 184         }
 185
 186         real_seconds = nowtime % 60;
 187         real_minutes = nowtime / 60;
 188         if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
 189                 real_minutes += 30;
 190         real_minutes %= 60;
 191         eft.minute = real_minutes;
 192         eft.second = real_seconds;
 193
 194         status = efi.set_time(&eft);
 195         if (status != EFI_SUCCESS) {
 196                 printk(KERN_ERR "Oops: efitime: can't write time!\n");
 197                 return -1;
 198         }
 199         return 0;
 200 }
 201
 202 unsigned long efi_get_time(void)
 203 {
 204         efi_status_t status;
 205         efi_time_t eft;
 206         efi_time_cap_t cap;
 207
 208         status = efi.get_time(&eft, &cap);
 209         if (status != EFI_SUCCESS)
 210                 printk(KERN_ERR "Oops: efitime: can't read time!\n");
 211
 212         return mktime(eft.year, eft.month, eft.day, eft.hour,
 213                       eft.minute, eft.second);
 214 }
 215
 216 #if EFI_DEBUG
 217 static void __init print_efi_memmap(void)
 218 {
 219         efi_memory_desc_t *md;
 220         void *p;
 221         int i;
 222
 223         for (p = memmap.map, i = 0;
 224              p < memmap.map_end;
 225              p += memmap.desc_size, i++) {
 226                 md = p;
 227                 printk(KERN_INFO PFX "mem%02u: type=%u, attr=0x%llx, "
 228                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
 229                         i, md->type, md->attribute, md->phys_addr,
 230                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
 231                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
 232         }
 233 }
 234 #endif  /*  EFI_DEBUG  */
 235
 236 void __init efi_init(void)
 237 {
 238         efi_config_table_t *config_tables;
 239         efi_runtime_services_t *runtime;
 240         efi_char16_t *c16;
 241         char vendor[100] = "unknown";
 242         int i = 0;
 243         void *tmp;
 244
 245 #ifdef CONFIG_X86_32
 246         efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
 247         memmap.phys_map = (void *)boot_params.efi_info.efi_memmap;
 248 #else
 249         efi_phys.systab = (efi_system_table_t *)
 250                 (boot_params.efi_info.efi_systab |
 251                  ((__u64)boot_params.efi_info.efi_systab_hi<<32));
 252         memmap.phys_map = (void *)
 253                 (boot_params.efi_info.efi_memmap |
 254                  ((__u64)boot_params.efi_info.efi_memmap_hi<<32));
 255 #endif
 256         memmap.nr_map = boot_params.efi_info.efi_memmap_size /
 257                 boot_params.efi_info.efi_memdesc_size;
 258         memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
 259         memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
 260
 261         efi.systab = early_ioremap((unsigned long)efi_phys.systab,
 262                                    sizeof(efi_system_table_t));
 263         if (efi.systab == NULL)
 264                 printk(KERN_ERR "Couldn't map the EFI system table!\n");
 265         memcpy(&efi_systab, efi.systab, sizeof(efi_system_table_t));
 266         early_iounmap(efi.systab, sizeof(efi_system_table_t));
 267         efi.systab = &efi_systab;
 268
 269         /*
 270          * Verify the EFI Table
 271          */
 272         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
 273                 printk(KERN_ERR "EFI system table signature incorrect!\n");
 274         if ((efi.systab->hdr.revision >> 16) == 0)
 275                 printk(KERN_ERR "Warning: EFI system table version "
 276                        "%d.%02d, expected 1.00 or greater!\n",
 277                        efi.systab->hdr.revision >> 16,
 278                        efi.systab->hdr.revision & 0xffff);
 279
 280         /*
 281          * Show what we know for posterity
 282          */
 283         c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
 284         if (c16) {
 285                 for (i = 0; i < sizeof(vendor) && *c16; ++i)
 286                         vendor[i] = *c16++;
 287                 vendor[i] = '\0';
 288         } else
 289                 printk(KERN_ERR PFX "Could not map the firmware vendor!\n");
 290         early_iounmap(tmp, 2);
 291
 292         printk(KERN_INFO "EFI v%u.%.02u by %s \n",
 293                efi.systab->hdr.revision >> 16,
 294                efi.systab->hdr.revision & 0xffff, vendor);
 295
 296         /*
 297          * Let's see what config tables the firmware passed to us.
 298          */
 299         config_tables = early_ioremap(
 300                 efi.systab->tables,
 301                 efi.systab->nr_tables * sizeof(efi_config_table_t));
 302         if (config_tables == NULL)
 303                 printk(KERN_ERR "Could not map EFI Configuration Table!\n");
 304
 305         printk(KERN_INFO);
 306         for (i = 0; i < efi.systab->nr_tables; i++) {
 307                 if (!efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID)) {
 308                         efi.mps = config_tables[i].table;
 309                         printk(" MPS=0x%lx ", config_tables[i].table);
 310                 } else if (!efi_guidcmp(config_tables[i].guid,
 311                                         ACPI_20_TABLE_GUID)) {
 312                         efi.acpi20 = config_tables[i].table;
 313                         printk(" ACPI 2.0=0x%lx ", config_tables[i].table);
 314                 } else if (!efi_guidcmp(config_tables[i].guid,
 315                                         ACPI_TABLE_GUID)) {
 316                         efi.acpi = config_tables[i].table;
 317                         printk(" ACPI=0x%lx ", config_tables[i].table);
 318                 } else if (!efi_guidcmp(config_tables[i].guid,
 319                                         SMBIOS_TABLE_GUID)) {
 320                         efi.smbios = config_tables[i].table;
 321                         printk(" SMBIOS=0x%lx ", config_tables[i].table);
 322                 } else if (!efi_guidcmp(config_tables[i].guid,
 323                                         HCDP_TABLE_GUID)) {
 324                         efi.hcdp = config_tables[i].table;
 325                         printk(" HCDP=0x%lx ", config_tables[i].table);
 326                 } else if (!efi_guidcmp(config_tables[i].guid,
 327                                         UGA_IO_PROTOCOL_GUID)) {
 328                         efi.uga = config_tables[i].table;
 329                         printk(" UGA=0x%lx ", config_tables[i].table);
 330                 }
 331         }
 332         printk("\n");
 333         early_iounmap(config_tables,
 334                           efi.systab->nr_tables * sizeof(efi_config_table_t));
 335
 336         /*
 337          * Check out the runtime services table. We need to map
 338          * the runtime services table so that we can grab the physical
 339          * address of several of the EFI runtime functions, needed to
 340          * set the firmware into virtual mode.
 341          */
 342         runtime = early_ioremap((unsigned long)efi.systab->runtime,
 343                                 sizeof(efi_runtime_services_t));
 344         if (runtime != NULL) {
 345                 /*
 346                  * We will only need *early* access to the following
 347                  * two EFI runtime services before set_virtual_address_map
 348                  * is invoked.
 349                  */
 350                 efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
 351                 efi_phys.set_virtual_address_map =
 352                         (efi_set_virtual_address_map_t *)
 353                         runtime->set_virtual_address_map;
 354                 /*
 355                  * Make efi_get_time can be called before entering
 356                  * virtual mode.
 357                  */
 358                 efi.get_time = phys_efi_get_time;
 359         } else
 360                 printk(KERN_ERR "Could not map the EFI runtime service "
 361                        "table!\n");
 362         early_iounmap(runtime, sizeof(efi_runtime_services_t));
 363
 364         /* Map the EFI memory map */
 365         memmap.map = early_ioremap((unsigned long)memmap.phys_map,
 366                                    memmap.nr_map * memmap.desc_size);
 367         if (memmap.map == NULL)
 368                 printk(KERN_ERR "Could not map the EFI memory map!\n");
 369         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
 370         if (memmap.desc_size != sizeof(efi_memory_desc_t))
 371                 printk(KERN_WARNING "Kernel-defined memdesc"
 372                        "doesn't match the one from EFI!\n");
 373
 374 #ifdef CONFIG_X86_64
 375         /* Setup for EFI runtime service */
 376         reboot_type = BOOT_EFI;
 377
 378 #endif
 379 #if EFI_DEBUG
 380         print_efi_memmap();
 381 #endif
 382 }
 383
 384 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
 385 static void __init runtime_code_page_mkexec(void)
 386 {
 387         efi_memory_desc_t *md;
 388         unsigned long end;
 389         void *p;
 390
 391         if (!(__supported_pte_mask & _PAGE_NX))
 392                 return;
 393
 394         /* Make EFI runtime service code area executable */
 395         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 396                 md = p;
 397                 end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT);
 398                 if (md->type == EFI_RUNTIME_SERVICES_CODE &&
 399                     (end >> PAGE_SHIFT) <= end_pfn_map)
 400                         change_page_attr_addr(md->virt_addr,
 401                                               md->num_pages,
 402                                               PAGE_KERNEL_EXEC_NOCACHE);
 403         }
 404         __flush_tlb_all();
 405 }
 406 #else
 407 static inline void __init runtime_code_page_mkexec(void) { }
 408 #endif
 409
 410 /*
 411  * This function will switch the EFI runtime services to virtual mode.
 412  * Essentially, look through the EFI memmap and map every region that
 413  * has the runtime attribute bit set in its memory descriptor and update
 414  * that memory descriptor with the virtual address obtained from ioremap().
 415  * This enables the runtime services to be called without having to
 416  * thunk back into physical mode for every invocation.
 417  */
 418 void __init efi_enter_virtual_mode(void)
 419 {
 420         efi_memory_desc_t *md;
 421         efi_status_t status;
 422         unsigned long end;
 423         void *p;
 424
 425         efi.systab = NULL;
 426         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 427                 md = p;
 428                 if (!(md->attribute & EFI_MEMORY_RUNTIME))
 429                         continue;
 430                 end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT);
 431                 if ((md->attribute & EFI_MEMORY_WB) &&
 432                     ((end >> PAGE_SHIFT) <= end_pfn_map))
 433                         md->virt_addr = (unsigned long)__va(md->phys_addr);
 434                 else
 435                         md->virt_addr = (unsigned long)
 436                                 efi_ioremap(md->phys_addr,
 437                                             md->num_pages << EFI_PAGE_SHIFT);
 438                 if (!md->virt_addr)
 439                         printk(KERN_ERR PFX "ioremap of 0x%llX failed!\n",
 440                                (unsigned long long)md->phys_addr);
 441                 if ((md->phys_addr <= (unsigned long)efi_phys.systab) &&
 442                     ((unsigned long)efi_phys.systab < end))
 443                         efi.systab = (efi_system_table_t *)(unsigned long)
 444                                 (md->virt_addr - md->phys_addr +
 445                                  (unsigned long)efi_phys.systab);
 446         }
 447
 448         BUG_ON(!efi.systab);
 449
 450         status = phys_efi_set_virtual_address_map(
 451                 memmap.desc_size * memmap.nr_map,
 452                 memmap.desc_size,
 453                 memmap.desc_version,
 454                 memmap.phys_map);
 455
 456         if (status != EFI_SUCCESS) {
 457                 printk(KERN_ALERT "Unable to switch EFI into virtual mode "
 458                        "(status=%lx)!\n", status);
 459                 panic("EFI call to SetVirtualAddressMap() failed!");
 460         }
 461
 462         /*
 463          * Now that EFI is in virtual mode, update the function
 464          * pointers in the runtime service table to the new virtual addresses.
 465          *
 466          * Call EFI services through wrapper functions.
 467          */
 468         efi.get_time = virt_efi_get_time;
 469         efi.set_time = virt_efi_set_time;
 470         efi.get_wakeup_time = virt_efi_get_wakeup_time;
 471         efi.set_wakeup_time = virt_efi_set_wakeup_time;
 472         efi.get_variable = virt_efi_get_variable;
 473         efi.get_next_variable = virt_efi_get_next_variable;
 474         efi.set_variable = virt_efi_set_variable;
 475         efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
 476         efi.reset_system = virt_efi_reset_system;
 477         efi.set_virtual_address_map = virt_efi_set_virtual_address_map;
 478         runtime_code_page_mkexec();
 479 }
 480
 481 /*
 482  * Convenience functions to obtain memory types and attributes
 483  */
 484 u32 efi_mem_type(unsigned long phys_addr)
 485 {
 486         efi_memory_desc_t *md;
 487         void *p;
 488
 489         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 490                 md = p;
 491                 if ((md->phys_addr <= phys_addr) &&
 492                     (phys_addr < (md->phys_addr +
 493                                   (md->num_pages << EFI_PAGE_SHIFT))))
 494                         return md->type;
 495         }
 496         return 0;
 497 }
 498
 499 u64 efi_mem_attributes(unsigned long phys_addr)
 500 {
 501         efi_memory_desc_t *md;
 502         void *p;
 503
 504         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 505                 md = p;
 506                 if ((md->phys_addr <= phys_addr) &&
 507                     (phys_addr < (md->phys_addr +
 508                                   (md->num_pages << EFI_PAGE_SHIFT))))
 509                         return md->attribute;
 510         }
 511         return 0;
 512 }