include/linux/efi.h

   1 #ifndef _LINUX_EFI_H
   2 #define _LINUX_EFI_H
   3
   4 /*
   5  * Extensible Firmware Interface
   6  * Based on 'Extensible Firmware Interface Specification' version 0.9, April 30, 1999
   7  *
   8  * Copyright (C) 1999 VA Linux Systems
   9  * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
  10  * Copyright (C) 1999, 2002-2003 Hewlett-Packard Co.
  11  *      David Mosberger-Tang <davidm@hpl.hp.com>
  12  *      Stephane Eranian <eranian@hpl.hp.com>
  13  */
  14 #include <linux/init.h>
  15 #include <linux/string.h>
  16 #include <linux/time.h>
  17 #include <linux/types.h>
  18 #include <linux/proc_fs.h>
  19 #include <linux/rtc.h>
  20 #include <linux/ioport.h>
  21 #include <linux/pfn.h>
  22 #include <linux/pstore.h>
  23
  24 #include <asm/page.h>
  25 #include <asm/system.h>
  26
  27 #define EFI_SUCCESS             0
  28 #define EFI_LOAD_ERROR          ( 1 | (1UL << (BITS_PER_LONG-1)))
  29 #define EFI_INVALID_PARAMETER   ( 2 | (1UL << (BITS_PER_LONG-1)))
  30 #define EFI_UNSUPPORTED         ( 3 | (1UL << (BITS_PER_LONG-1)))
  31 #define EFI_BAD_BUFFER_SIZE     ( 4 | (1UL << (BITS_PER_LONG-1)))
  32 #define EFI_BUFFER_TOO_SMALL    ( 5 | (1UL << (BITS_PER_LONG-1)))
  33 #define EFI_NOT_FOUND           (14 | (1UL << (BITS_PER_LONG-1)))
  34
  35 typedef unsigned long efi_status_t;
  36 typedef u8 efi_bool_t;
  37 typedef u16 efi_char16_t;               /* UNICODE character */
  38
  39
  40 typedef struct {
  41         u8 b[16];
  42 } efi_guid_t;
  43
  44 #define EFI_GUID(a,b,c,d0,d1,d2,d3,d4,d5,d6,d7) \
  45 ((efi_guid_t) \
  46 {{ (a) & 0xff, ((a) >> 8) & 0xff, ((a) >> 16) & 0xff, ((a) >> 24) & 0xff, \
  47   (b) & 0xff, ((b) >> 8) & 0xff, \
  48   (c) & 0xff, ((c) >> 8) & 0xff, \
  49   (d0), (d1), (d2), (d3), (d4), (d5), (d6), (d7) }})
  50
  51 /*
  52  * Generic EFI table header
  53  */
  54 typedef struct {
  55         u64 signature;
  56         u32 revision;
  57         u32 headersize;
  58         u32 crc32;
  59         u32 reserved;
  60 } efi_table_hdr_t;
  61
  62 /*
  63  * Memory map descriptor:
  64  */
  65
  66 /* Memory types: */
  67 #define EFI_RESERVED_TYPE                0
  68 #define EFI_LOADER_CODE                  1
  69 #define EFI_LOADER_DATA                  2
  70 #define EFI_BOOT_SERVICES_CODE           3
  71 #define EFI_BOOT_SERVICES_DATA           4
  72 #define EFI_RUNTIME_SERVICES_CODE        5
  73 #define EFI_RUNTIME_SERVICES_DATA        6
  74 #define EFI_CONVENTIONAL_MEMORY          7
  75 #define EFI_UNUSABLE_MEMORY              8
  76 #define EFI_ACPI_RECLAIM_MEMORY          9
  77 #define EFI_ACPI_MEMORY_NVS             10
  78 #define EFI_MEMORY_MAPPED_IO            11
  79 #define EFI_MEMORY_MAPPED_IO_PORT_SPACE 12
  80 #define EFI_PAL_CODE                    13
  81 #define EFI_MAX_MEMORY_TYPE             14
  82
  83 /* Attribute values: */
  84 #define EFI_MEMORY_UC           ((u64)0x0000000000000001ULL)    /* uncached */
  85 #define EFI_MEMORY_WC           ((u64)0x0000000000000002ULL)    /* write-coalescing */
  86 #define EFI_MEMORY_WT           ((u64)0x0000000000000004ULL)    /* write-through */
  87 #define EFI_MEMORY_WB           ((u64)0x0000000000000008ULL)    /* write-back */
  88 #define EFI_MEMORY_WP           ((u64)0x0000000000001000ULL)    /* write-protect */
  89 #define EFI_MEMORY_RP           ((u64)0x0000000000002000ULL)    /* read-protect */
  90 #define EFI_MEMORY_XP           ((u64)0x0000000000004000ULL)    /* execute-protect */
  91 #define EFI_MEMORY_RUNTIME      ((u64)0x8000000000000000ULL)    /* range requires runtime mapping */
  92 #define EFI_MEMORY_DESCRIPTOR_VERSION   1
  93
  94 #define EFI_PAGE_SHIFT          12
  95
  96 typedef struct {
  97         u32 type;
  98         u32 pad;
  99         u64 phys_addr;
 100         u64 virt_addr;
 101         u64 num_pages;
 102         u64 attribute;
 103 } efi_memory_desc_t;
 104
 105 typedef struct {
 106         efi_guid_t guid;
 107         u32 headersize;
 108         u32 flags;
 109         u32 imagesize;
 110 } efi_capsule_header_t;
 111
 112 /*
 113  * Allocation types for calls to boottime->allocate_pages.
 114  */
 115 #define EFI_ALLOCATE_ANY_PAGES          0
 116 #define EFI_ALLOCATE_MAX_ADDRESS        1
 117 #define EFI_ALLOCATE_ADDRESS            2
 118 #define EFI_MAX_ALLOCATE_TYPE           3
 119
 120 typedef int (*efi_freemem_callback_t) (u64 start, u64 end, void *arg);
 121
 122 /*
 123  * Types and defines for Time Services
 124  */
 125 #define EFI_TIME_ADJUST_DAYLIGHT 0x1
 126 #define EFI_TIME_IN_DAYLIGHT     0x2
 127 #define EFI_UNSPECIFIED_TIMEZONE 0x07ff
 128
 129 typedef struct {
 130         u16 year;
 131         u8 month;
 132         u8 day;
 133         u8 hour;
 134         u8 minute;
 135         u8 second;
 136         u8 pad1;
 137         u32 nanosecond;
 138         s16 timezone;
 139         u8 daylight;
 140         u8 pad2;
 141 } efi_time_t;
 142
 143 typedef struct {
 144         u32 resolution;
 145         u32 accuracy;
 146         u8 sets_to_zero;
 147 } efi_time_cap_t;
 148
 149 /*
 150  * EFI Boot Services table
 151  */
 152 typedef struct {
 153         efi_table_hdr_t hdr;
 154         void *raise_tpl;
 155         void *restore_tpl;
 156         void *allocate_pages;
 157         void *free_pages;
 158         void *get_memory_map;
 159         void *allocate_pool;
 160         void *free_pool;
 161         void *create_event;
 162         void *set_timer;
 163         void *wait_for_event;
 164         void *signal_event;
 165         void *close_event;
 166         void *check_event;
 167         void *install_protocol_interface;
 168         void *reinstall_protocol_interface;
 169         void *uninstall_protocol_interface;
 170         void *handle_protocol;
 171         void *__reserved;
 172         void *register_protocol_notify;
 173         void *locate_handle;
 174         void *locate_device_path;
 175         void *install_configuration_table;
 176         void *load_image;
 177         void *start_image;
 178         void *exit;
 179         void *unload_image;
 180         void *exit_boot_services;
 181         void *get_next_monotonic_count;
 182         void *stall;
 183         void *set_watchdog_timer;
 184         void *connect_controller;
 185         void *disconnect_controller;
 186         void *open_protocol;
 187         void *close_protocol;
 188         void *open_protocol_information;
 189         void *protocols_per_handle;
 190         void *locate_handle_buffer;
 191         void *locate_protocol;
 192         void *install_multiple_protocol_interfaces;
 193         void *uninstall_multiple_protocol_interfaces;
 194         void *calculate_crc32;
 195         void *copy_mem;
 196         void *set_mem;
 197         void *create_event_ex;
 198 } efi_boot_services_t;
 199
 200 /*
 201  * Types and defines for EFI ResetSystem
 202  */
 203 #define EFI_RESET_COLD 0
 204 #define EFI_RESET_WARM 1
 205 #define EFI_RESET_SHUTDOWN 2
 206
 207 /*
 208  * EFI Runtime Services table
 209  */
 210 #define EFI_RUNTIME_SERVICES_SIGNATURE ((u64)0x5652453544e5552ULL)
 211 #define EFI_RUNTIME_SERVICES_REVISION  0x00010000
 212
 213 typedef struct {
 214         efi_table_hdr_t hdr;
 215         unsigned long get_time;
 216         unsigned long set_time;
 217         unsigned long get_wakeup_time;
 218         unsigned long set_wakeup_time;
 219         unsigned long set_virtual_address_map;
 220         unsigned long convert_pointer;
 221         unsigned long get_variable;
 222         unsigned long get_next_variable;
 223         unsigned long set_variable;
 224         unsigned long get_next_high_mono_count;
 225         unsigned long reset_system;
 226         unsigned long update_capsule;
 227         unsigned long query_capsule_caps;
 228         unsigned long query_variable_info;
 229 } efi_runtime_services_t;
 230
 231 typedef efi_status_t efi_get_time_t (efi_time_t *tm, efi_time_cap_t *tc);
 232 typedef efi_status_t efi_set_time_t (efi_time_t *tm);
 233 typedef efi_status_t efi_get_wakeup_time_t (efi_bool_t *enabled, efi_bool_t *pending,
 234                                             efi_time_t *tm);
 235 typedef efi_status_t efi_set_wakeup_time_t (efi_bool_t enabled, efi_time_t *tm);
 236 typedef efi_status_t efi_get_variable_t (efi_char16_t *name, efi_guid_t *vendor, u32 *attr,
 237                                          unsigned long *data_size, void *data);
 238 typedef efi_status_t efi_get_next_variable_t (unsigned long *name_size, efi_char16_t *name,
 239                                               efi_guid_t *vendor);
 240 typedef efi_status_t efi_set_variable_t (efi_char16_t *name, efi_guid_t *vendor,
 241                                          u32 attr, unsigned long data_size,
 242                                          void *data);
 243 typedef efi_status_t efi_get_next_high_mono_count_t (u32 *count);
 244 typedef void efi_reset_system_t (int reset_type, efi_status_t status,
 245                                  unsigned long data_size, efi_char16_t *data);
 246 typedef efi_status_t efi_set_virtual_address_map_t (unsigned long memory_map_size,
 247                                                 unsigned long descriptor_size,
 248                                                 u32 descriptor_version,
 249                                                 efi_memory_desc_t *virtual_map);
 250 typedef efi_status_t efi_query_variable_info_t(u32 attr,
 251                                                u64 *storage_space,
 252                                                u64 *remaining_space,
 253                                                u64 *max_variable_size);
 254 typedef efi_status_t efi_update_capsule_t(efi_capsule_header_t **capsules,
 255                                           unsigned long count,
 256                                           unsigned long sg_list);
 257 typedef efi_status_t efi_query_capsule_caps_t(efi_capsule_header_t **capsules,
 258                                               unsigned long count,
 259                                               u64 *max_size,
 260                                               int *reset_type);
 261
 262 /*
 263  *  EFI Configuration Table and GUID definitions
 264  */
 265 #define NULL_GUID \
 266     EFI_GUID(  0x00000000, 0x0000, 0x0000, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 )
 267
 268 #define MPS_TABLE_GUID    \
 269     EFI_GUID(  0xeb9d2d2f, 0x2d88, 0x11d3, 0x9a, 0x16, 0x0, 0x90, 0x27, 0x3f, 0xc1, 0x4d )
 270
 271 #define ACPI_TABLE_GUID    \
 272     EFI_GUID(  0xeb9d2d30, 0x2d88, 0x11d3, 0x9a, 0x16, 0x0, 0x90, 0x27, 0x3f, 0xc1, 0x4d )
 273
 274 #define ACPI_20_TABLE_GUID    \
 275     EFI_GUID(  0x8868e871, 0xe4f1, 0x11d3, 0xbc, 0x22, 0x0, 0x80, 0xc7, 0x3c, 0x88, 0x81 )
 276
 277 #define SMBIOS_TABLE_GUID    \
 278     EFI_GUID(  0xeb9d2d31, 0x2d88, 0x11d3, 0x9a, 0x16, 0x0, 0x90, 0x27, 0x3f, 0xc1, 0x4d )
 279
 280 #define SAL_SYSTEM_TABLE_GUID    \
 281     EFI_GUID(  0xeb9d2d32, 0x2d88, 0x11d3, 0x9a, 0x16, 0x0, 0x90, 0x27, 0x3f, 0xc1, 0x4d )
 282
 283 #define HCDP_TABLE_GUID \
 284     EFI_GUID(  0xf951938d, 0x620b, 0x42ef, 0x82, 0x79, 0xa8, 0x4b, 0x79, 0x61, 0x78, 0x98 )
 285
 286 #define UGA_IO_PROTOCOL_GUID \
 287     EFI_GUID(  0x61a4d49e, 0x6f68, 0x4f1b, 0xb9, 0x22, 0xa8, 0x6e, 0xed, 0xb, 0x7, 0xa2 )
 288
 289 #define EFI_GLOBAL_VARIABLE_GUID \
 290     EFI_GUID(  0x8be4df61, 0x93ca, 0x11d2, 0xaa, 0x0d, 0x00, 0xe0, 0x98, 0x03, 0x2b, 0x8c )
 291
 292 #define UV_SYSTEM_TABLE_GUID \
 293     EFI_GUID(  0x3b13a7d4, 0x633e, 0x11dd, 0x93, 0xec, 0xda, 0x25, 0x56, 0xd8, 0x95, 0x93 )
 294
 295 #define LINUX_EFI_CRASH_GUID \
 296     EFI_GUID(  0xcfc8fc79, 0xbe2e, 0x4ddc, 0x97, 0xf0, 0x9f, 0x98, 0xbf, 0xe2, 0x98, 0xa0 )
 297
 298 #define LOADED_IMAGE_PROTOCOL_GUID \
 299     EFI_GUID(  0x5b1b31a1, 0x9562, 0x11d2, 0x8e, 0x3f, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b )
 300
 301 #define EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID \
 302     EFI_GUID(  0x9042a9de, 0x23dc, 0x4a38, 0x96, 0xfb, 0x7a, 0xde, 0xd0, 0x80, 0x51, 0x6a )
 303
 304 #define EFI_UGA_PROTOCOL_GUID \
 305     EFI_GUID(  0x982c298b, 0xf4fa, 0x41cb, 0xb8, 0x38, 0x77, 0xaa, 0x68, 0x8f, 0xb8, 0x39 )
 306
 307 #define EFI_PCI_IO_PROTOCOL_GUID \
 308     EFI_GUID(  0x4cf5b200, 0x68b8, 0x4ca5, 0x9e, 0xec, 0xb2, 0x3e, 0x3f, 0x50, 0x2, 0x9a )
 309
 310 typedef struct {
 311         efi_guid_t guid;
 312         unsigned long table;
 313 } efi_config_table_t;
 314
 315 #define EFI_SYSTEM_TABLE_SIGNATURE ((u64)0x5453595320494249ULL)
 316
 317 #define EFI_2_30_SYSTEM_TABLE_REVISION  ((2 << 16) | (30))
 318 #define EFI_2_20_SYSTEM_TABLE_REVISION  ((2 << 16) | (20))
 319 #define EFI_2_10_SYSTEM_TABLE_REVISION  ((2 << 16) | (10))
 320 #define EFI_2_00_SYSTEM_TABLE_REVISION  ((2 << 16) | (00))
 321 #define EFI_1_10_SYSTEM_TABLE_REVISION  ((1 << 16) | (10))
 322 #define EFI_1_02_SYSTEM_TABLE_REVISION  ((1 << 16) | (02))
 323
 324 typedef struct {
 325         efi_table_hdr_t hdr;
 326         unsigned long fw_vendor;        /* physical addr of CHAR16 vendor string */
 327         u32 fw_revision;
 328         unsigned long con_in_handle;
 329         unsigned long con_in;
 330         unsigned long con_out_handle;
 331         unsigned long con_out;
 332         unsigned long stderr_handle;
 333         unsigned long stderr;
 334         efi_runtime_services_t *runtime;
 335         efi_boot_services_t *boottime;
 336         unsigned long nr_tables;
 337         unsigned long tables;
 338 } efi_system_table_t;
 339
 340 struct efi_memory_map {
 341         void *phys_map;
 342         void *map;
 343         void *map_end;
 344         int nr_map;
 345         unsigned long desc_version;
 346         unsigned long desc_size;
 347 };
 348
 349 typedef struct {
 350         u32 revision;
 351         void *parent_handle;
 352         efi_system_table_t *system_table;
 353         void *device_handle;
 354         void *file_path;
 355         void *reserved;
 356         u32 load_options_size;
 357         void *load_options;
 358         void *image_base;
 359         __aligned_u64 image_size;
 360         unsigned int image_code_type;
 361         unsigned int image_data_type;
 362         unsigned long unload;
 363 } efi_loaded_image_t;
 364
 365 #define EFI_INVALID_TABLE_ADDR          (~0UL)
 366
 367 /*
 368  * All runtime access to EFI goes through this structure:
 369  */
 370 extern struct efi {
 371         efi_system_table_t *systab;     /* EFI system table */
 372         unsigned int runtime_version;   /* Runtime services version */
 373         unsigned long mps;              /* MPS table */
 374         unsigned long acpi;             /* ACPI table  (IA64 ext 0.71) */
 375         unsigned long acpi20;           /* ACPI table  (ACPI 2.0) */
 376         unsigned long smbios;           /* SM BIOS table */
 377         unsigned long sal_systab;       /* SAL system table */
 378         unsigned long boot_info;        /* boot info table */
 379         unsigned long hcdp;             /* HCDP table */
 380         unsigned long uga;              /* UGA table */
 381         unsigned long uv_systab;        /* UV system table */
 382         efi_get_time_t *get_time;
 383         efi_set_time_t *set_time;
 384         efi_get_wakeup_time_t *get_wakeup_time;
 385         efi_set_wakeup_time_t *set_wakeup_time;
 386         efi_get_variable_t *get_variable;
 387         efi_get_next_variable_t *get_next_variable;
 388         efi_set_variable_t *set_variable;
 389         efi_query_variable_info_t *query_variable_info;
 390         efi_update_capsule_t *update_capsule;
 391         efi_query_capsule_caps_t *query_capsule_caps;
 392         efi_get_next_high_mono_count_t *get_next_high_mono_count;
 393         efi_reset_system_t *reset_system;
 394         efi_set_virtual_address_map_t *set_virtual_address_map;
 395 } efi;
 396
 397 static inline int
 398 efi_guidcmp (efi_guid_t left, efi_guid_t right)
 399 {
 400         return memcmp(&left, &right, sizeof (efi_guid_t));
 401 }
 402
 403 static inline char *
 404 efi_guid_unparse(efi_guid_t *guid, char *out)
 405 {
 406         sprintf(out, "%pUl", guid->b);
 407         return out;
 408 }
 409
 410 extern void efi_init (void);
 411 extern void *efi_get_pal_addr (void);
 412 extern void efi_map_pal_code (void);
 413 extern void efi_memmap_walk (efi_freemem_callback_t callback, void *arg);
 414 extern void efi_gettimeofday (struct timespec *ts);
 415 extern void efi_enter_virtual_mode (void);      /* switch EFI to virtual mode, if possible */
 416 extern u64 efi_get_iobase (void);
 417 extern u32 efi_mem_type (unsigned long phys_addr);
 418 extern u64 efi_mem_attributes (unsigned long phys_addr);
 419 extern u64 efi_mem_attribute (unsigned long phys_addr, unsigned long size);
 420 extern int __init efi_uart_console_only (void);
 421 extern void efi_initialize_iomem_resources(struct resource *code_resource,
 422                 struct resource *data_resource, struct resource *bss_resource);
 423 extern unsigned long efi_get_time(void);
 424 extern int efi_set_rtc_mmss(unsigned long nowtime);
 425 extern void efi_reserve_boot_services(void);
 426 extern struct efi_memory_map memmap;
 427
 428 /**
 429  * efi_range_is_wc - check the WC bit on an address range
 430  * @start: starting kvirt address
 431  * @len: length of range
 432  *
 433  * Consult the EFI memory map and make sure it's ok to set this range WC.
 434  * Returns true or false.
 435  */
 436 static inline int efi_range_is_wc(unsigned long start, unsigned long len)
 437 {
 438         unsigned long i;
 439
 440         for (i = 0; i < len; i += (1UL << EFI_PAGE_SHIFT)) {
 441                 unsigned long paddr = __pa(start + i);
 442                 if (!(efi_mem_attributes(paddr) & EFI_MEMORY_WC))
 443                         return 0;
 444         }
 445         /* The range checked out */
 446         return 1;
 447 }
 448
 449 #ifdef CONFIG_EFI_PCDP
 450 extern int __init efi_setup_pcdp_console(char *);
 451 #endif
 452
 453 /*
 454  * We play games with efi_enabled so that the compiler will, if possible, remove
 455  * EFI-related code altogether.
 456  */
 457 #ifdef CONFIG_EFI
 458 # ifdef CONFIG_X86
 459    extern int efi_enabled;
 460 # else
 461 #  define efi_enabled 1
 462 # endif
 463 #else
 464 # define efi_enabled 0
 465 #endif
 466
 467 /*
 468  * Variable Attributes
 469  */
 470 #define EFI_VARIABLE_NON_VOLATILE       0x0000000000000001
 471 #define EFI_VARIABLE_BOOTSERVICE_ACCESS 0x0000000000000002
 472 #define EFI_VARIABLE_RUNTIME_ACCESS     0x0000000000000004
 473
 474 /*
 475  * EFI Device Path information
 476  */
 477 #define EFI_DEV_HW                      0x01
 478 #define  EFI_DEV_PCI                             1
 479 #define  EFI_DEV_PCCARD                          2
 480 #define  EFI_DEV_MEM_MAPPED                      3
 481 #define  EFI_DEV_VENDOR                          4
 482 #define  EFI_DEV_CONTROLLER                      5
 483 #define EFI_DEV_ACPI                    0x02
 484 #define   EFI_DEV_BASIC_ACPI                     1
 485 #define   EFI_DEV_EXPANDED_ACPI                  2
 486 #define EFI_DEV_MSG                     0x03
 487 #define   EFI_DEV_MSG_ATAPI                      1
 488 #define   EFI_DEV_MSG_SCSI                       2
 489 #define   EFI_DEV_MSG_FC                         3
 490 #define   EFI_DEV_MSG_1394                       4
 491 #define   EFI_DEV_MSG_USB                        5
 492 #define   EFI_DEV_MSG_USB_CLASS                 15
 493 #define   EFI_DEV_MSG_I20                        6
 494 #define   EFI_DEV_MSG_MAC                       11
 495 #define   EFI_DEV_MSG_IPV4                      12
 496 #define   EFI_DEV_MSG_IPV6                      13
 497 #define   EFI_DEV_MSG_INFINIBAND                 9
 498 #define   EFI_DEV_MSG_UART                      14
 499 #define   EFI_DEV_MSG_VENDOR                    10
 500 #define EFI_DEV_MEDIA                   0x04
 501 #define   EFI_DEV_MEDIA_HARD_DRIVE               1
 502 #define   EFI_DEV_MEDIA_CDROM                    2
 503 #define   EFI_DEV_MEDIA_VENDOR                   3
 504 #define   EFI_DEV_MEDIA_FILE                     4
 505 #define   EFI_DEV_MEDIA_PROTOCOL                 5
 506 #define EFI_DEV_BIOS_BOOT               0x05
 507 #define EFI_DEV_END_PATH                0x7F
 508 #define EFI_DEV_END_PATH2               0xFF
 509 #define   EFI_DEV_END_INSTANCE                  0x01
 510 #define   EFI_DEV_END_ENTIRE                    0xFF
 511
 512 struct efi_generic_dev_path {
 513         u8 type;
 514         u8 sub_type;
 515         u16 length;
 516 } __attribute ((packed));
 517
 518 static inline void memrange_efi_to_native(u64 *addr, u64 *npages)
 519 {
 520         *npages = PFN_UP(*addr + (*npages<<EFI_PAGE_SHIFT)) - PFN_DOWN(*addr);
 521         *addr &= PAGE_MASK;
 522 }
 523
 524 #if defined(CONFIG_EFI_VARS) || defined(CONFIG_EFI_VARS_MODULE)
 525 /*
 526  * EFI Variable support.
 527  *
 528  * Different firmware drivers can expose their EFI-like variables using
 529  * the following.
 530  */
 531
 532 struct efivar_operations {
 533         efi_get_variable_t *get_variable;
 534         efi_get_next_variable_t *get_next_variable;
 535         efi_set_variable_t *set_variable;
 536 };
 537
 538 struct efivars {
 539         /*
 540          * ->lock protects two things:
 541          * 1) ->list - adds, removals, reads, writes
 542          * 2) ops.[gs]et_variable() calls.
 543          * It must not be held when creating sysfs entries or calling kmalloc.
 544          * ops.get_next_variable() is only called from register_efivars(),
 545          * which is protected by the BKL, so that path is safe.
 546          */
 547         spinlock_t lock;
 548         struct list_head list;
 549         struct kset *kset;
 550         struct bin_attribute *new_var, *del_var;
 551         const struct efivar_operations *ops;
 552         struct efivar_entry *walk_entry;
 553         struct pstore_info efi_pstore_info;
 554 };
 555
 556 int register_efivars(struct efivars *efivars,
 557                      const struct efivar_operations *ops,
 558                      struct kobject *parent_kobj);
 559 void unregister_efivars(struct efivars *efivars);
 560
 561 #endif /* CONFIG_EFI_VARS */
 562
 563 #endif /* _LINUX_EFI_H */