include/cbfs.h

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