include/cbfs.h

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
   4  */
   5
   6 #ifndef __CBFS_H
   7 #define __CBFS_H
   8
   9 #include <compiler.h>
  10 #include <linux/compiler.h>
  11
  12 enum cbfs_result {
  13         CBFS_SUCCESS = 0,
  14         CBFS_NOT_INITIALIZED,
  15         CBFS_BAD_HEADER,
  16         CBFS_BAD_FILE,
  17         CBFS_FILE_NOT_FOUND
  18 };
  19
  20 enum cbfs_filetype {
  21         CBFS_TYPE_BOOTBLOCK = 0x01,
  22         CBFS_TYPE_CBFSHEADER = 0x02,
  23         CBFS_TYPE_STAGE = 0x10,
  24         CBFS_TYPE_PAYLOAD = 0x20,
  25         CBFS_TYPE_FIT = 0x21,
  26         CBFS_TYPE_OPTIONROM = 0x30,
  27         CBFS_TYPE_BOOTSPLASH = 0x40,
  28         CBFS_TYPE_RAW = 0x50,
  29         CBFS_TYPE_VSA = 0x51,
  30         CBFS_TYPE_MBI = 0x52,
  31         CBFS_TYPE_MICROCODE = 0x53,
  32         CBFS_TYPE_FSP = 0x60,
  33         CBFS_TYPE_MRC = 0x61,
  34         CBFS_TYPE_MMA = 0x62,
  35         CBFS_TYPE_EFI = 0x63,
  36         CBFS_TYPE_STRUCT = 0x70,
  37         CBFS_TYPE_CMOS_DEFAULT = 0xaa,
  38         CBFS_TYPE_SPD = 0xab,
  39         CBFS_TYPE_MRC_CACHE = 0xac,
  40         CBFS_TYPE_CMOS_LAYOUT = 0x01aa
  41 };
  42
  43 enum {
  44         CBFS_HEADER_MAGIC       = 0x4f524243,
  45 };
  46
  47 /**
  48  * struct cbfs_header - header at the start of a CBFS region
  49  *
  50  * All fields use big-endian format.
  51  *
  52  * @magic: Magic number (CBFS_HEADER_MAGIC)
  53  */
  54 struct cbfs_header {
  55         u32 magic;
  56         u32 version;
  57         u32 rom_size;
  58         u32 boot_block_size;
  59         u32 align;
  60         u32 offset;
  61         u32 pad[2];
  62 } __packed;
  63
  64 struct cbfs_fileheader {
  65         u8 magic[8];
  66         u32 len;
  67         u32 type;
  68         /* offset to struct cbfs_file_attribute or 0 */
  69         u32 attributes_offset;
  70         u32 offset;
  71 } __packed;
  72
  73 struct cbfs_cachenode {
  74         struct cbfs_cachenode *next;
  75         u32 type;
  76         void *data;
  77         u32 data_length;
  78         char *name;
  79         u32 name_length;
  80         u32 attributes_offset;
  81 } __packed;
  82
  83 extern enum cbfs_result file_cbfs_result;
  84
  85 /**
  86  * file_cbfs_error() - Return a string describing the most recent error
  87  * condition.
  88  *
  89  * @return A pointer to the constant string.
  90  */
  91 const char *file_cbfs_error(void);
  92
  93 /**
  94  * file_cbfs_init() - Initialize the CBFS driver and load metadata into RAM.
  95  *
  96  * @end_of_rom: Points to the end of the ROM the CBFS should be read
  97  *                      from.
  98  */
  99 void file_cbfs_init(uintptr_t end_of_rom);
 100
 101 /**
 102  * file_cbfs_get_header() - Get the header structure for the current CBFS.
 103  *
 104  * @return A pointer to the constant structure, or NULL if there is none.
 105  */
 106 const struct cbfs_header *file_cbfs_get_header(void);
 107
 108 /**
 109  * file_cbfs_get_first() - Get a handle for the first file in CBFS.
 110  *
 111  * @return A handle for the first file in CBFS, NULL on error.
 112  */
 113 const struct cbfs_cachenode *file_cbfs_get_first(void);
 114
 115 /**
 116  * file_cbfs_get_next() - Get a handle to the file after this one in CBFS.
 117  *
 118  * @file:               A pointer to the handle to advance.
 119  */
 120 void file_cbfs_get_next(const struct cbfs_cachenode **file);
 121
 122 /**
 123  * file_cbfs_find() - Find a file with a particular name in CBFS.
 124  *
 125  * @name:               The name to search for.
 126  *
 127  * @return A handle to the file, or NULL on error.
 128  */
 129 const struct cbfs_cachenode *file_cbfs_find(const char *name);
 130
 131
 132 /***************************************************************************/
 133 /* All of the functions below can be used without first initializing CBFS. */
 134 /***************************************************************************/
 135
 136 /**
 137  * file_cbfs_find_uncached() - Find a file with a particular name in CBFS
 138  * without using the heap.
 139  *
 140  * @end_of_rom:         Points to the end of the ROM the CBFS should be read
 141  *                      from.
 142  * @name:               The name to search for.
 143  *
 144  * @return A handle to the file, or NULL on error.
 145  */
 146 const struct cbfs_cachenode *file_cbfs_find_uncached(uintptr_t end_of_rom,
 147                                                      const char *name);
 148
 149 /**
 150  * file_cbfs_name() - Get the name of a file in CBFS.
 151  *
 152  * @file:               The handle to the file.
 153  *
 154  * @return The name of the file, NULL on error.
 155  */
 156 const char *file_cbfs_name(const struct cbfs_cachenode *file);
 157
 158 /**
 159  * file_cbfs_size() - Get the size of a file in CBFS.
 160  *
 161  * @file:               The handle to the file.
 162  *
 163  * @return The size of the file, zero on error.
 164  */
 165 u32 file_cbfs_size(const struct cbfs_cachenode *file);
 166
 167 /**
 168  * file_cbfs_type() - Get the type of a file in CBFS.
 169  *
 170  * @file:               The handle to the file.
 171  *
 172  * @return The type of the file, zero on error.
 173  */
 174 u32 file_cbfs_type(const struct cbfs_cachenode *file);
 175
 176 /**
 177  * file_cbfs_read() - Read a file from CBFS into RAM
 178  *
 179  * @file:               A handle to the file to read.
 180  * @buffer:             Where to read it into memory.
 181  * @maxsize:            Maximum number of bytes to read
 182  *
 183  * @return If positive or zero, the number of characters read. If negative, an
 184  *         error occurred.
 185  */
 186 long file_cbfs_read(const struct cbfs_cachenode *file, void *buffer,
 187                     unsigned long maxsize);
 188
 189 #endif /* __CBFS_H */