include/cbfs.h

   1 /*
   2  * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
   3  *
   4  * See file CREDITS for list of people who contributed to this
   5  * project.
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation; either version 2 of
  10  * the License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  20  * MA 02111-1307 USA
  21  */
  22
  23 #ifndef __CBFS_H
  24 #define __CBFS_H
  25
  26 #include <compiler.h>
  27 #include <linux/compiler.h>
  28
  29 enum cbfs_result {
  30         CBFS_SUCCESS = 0,
  31         CBFS_NOT_INITIALIZED,
  32         CBFS_BAD_HEADER,
  33         CBFS_BAD_FILE,
  34         CBFS_FILE_NOT_FOUND
  35 };
  36
  37 enum cbfs_filetype {
  38         CBFS_TYPE_STAGE = 0x10,
  39         CBFS_TYPE_PAYLOAD = 0x20,
  40         CBFS_TYPE_OPTIONROM = 0x30,
  41         CBFS_TYPE_BOOTSPLASH = 0x40,
  42         CBFS_TYPE_RAW = 0x50,
  43         CBFS_TYPE_VSA = 0x51,
  44         CBFS_TYPE_MBI = 0x52,
  45         CBFS_TYPE_MICROCODE = 0x53,
  46         CBFS_COMPONENT_CMOS_DEFAULT = 0xaa,
  47         CBFS_COMPONENT_CMOS_LAYOUT = 0x01aa
  48 };
  49
  50 struct cbfs_header {
  51         u32 magic;
  52         u32 version;
  53         u32 rom_size;
  54         u32 boot_block_size;
  55         u32 align;
  56         u32 offset;
  57         u32 pad[2];
  58 } __packed;
  59
  60 struct cbfs_fileheader {
  61         u8 magic[8];
  62         u32 len;
  63         u32 type;
  64         u32 checksum;
  65         u32 offset;
  66 } __packed;
  67
  68 struct cbfs_cachenode {
  69         struct cbfs_cachenode *next;
  70         u32 type;
  71         void *data;
  72         u32 data_length;
  73         char *name;
  74         u32 name_length;
  75         u32 checksum;
  76 } __packed;
  77
  78 extern enum cbfs_result file_cbfs_result;
  79
  80 /*
  81  * Return a string describing the most recent error condition.
  82  *
  83  * @return A pointer to the constant string.
  84  */
  85 const char *file_cbfs_error(void);
  86
  87 /*
  88  * Initialize the CBFS driver and load metadata into RAM.
  89  *
  90  * @param end_of_rom    Points to the end of the ROM the CBFS should be read
  91  *                      from.
  92  */
  93 void file_cbfs_init(uintptr_t end_of_rom);
  94
  95 /*
  96  * Get the header structure for the current CBFS.
  97  *
  98  * @return A pointer to the constant structure, or NULL if there is none.
  99  */
 100 const struct cbfs_header *file_cbfs_get_header(void);
 101
 102 /*
 103  * Get a handle for the first file in CBFS.
 104  *
 105  * @return A handle for the first file in CBFS, NULL on error.
 106  */
 107 const struct cbfs_cachenode *file_cbfs_get_first(void);
 108
 109 /*
 110  * Get a handle to the file after this one in CBFS.
 111  *
 112  * @param file          A pointer to the handle to advance.
 113  */
 114 void file_cbfs_get_next(const struct cbfs_cachenode **file);
 115
 116 /*
 117  * Find a file with a particular name in CBFS.
 118  *
 119  * @param name          The name to search for.
 120  *
 121  * @return A handle to the file, or NULL on error.
 122  */
 123 const struct cbfs_cachenode *file_cbfs_find(const char *name);
 124
 125
 126 /***************************************************************************/
 127 /* All of the functions below can be used without first initializing CBFS. */
 128 /***************************************************************************/
 129
 130 /*
 131  * Find a file with a particular name in CBFS without using the heap.
 132  *
 133  * @param end_of_rom    Points to the end of the ROM the CBFS should be read
 134  *                      from.
 135  * @param name          The name to search for.
 136  *
 137  * @return A handle to the file, or NULL on error.
 138  */
 139 const struct cbfs_cachenode *file_cbfs_find_uncached(uintptr_t end_of_rom,
 140                                                      const char *name);
 141
 142 /*
 143  * Get the name of a file in CBFS.
 144  *
 145  * @param file          The handle to the file.
 146  *
 147  * @return The name of the file, NULL on error.
 148  */
 149 const char *file_cbfs_name(const struct cbfs_cachenode *file);
 150
 151 /*
 152  * Get the size of a file in CBFS.
 153  *
 154  * @param file          The handle to the file.
 155  *
 156  * @return The size of the file, zero on error.
 157  */
 158 u32 file_cbfs_size(const struct cbfs_cachenode *file);
 159
 160 /*
 161  * Get the type of a file in CBFS.
 162  *
 163  * @param file          The handle to the file.
 164  *
 165  * @return The type of the file, zero on error.
 166  */
 167 u32 file_cbfs_type(const struct cbfs_cachenode *file);
 168
 169 /*
 170  * Read a file from CBFS into RAM
 171  *
 172  * @param file          A handle to the file to read.
 173  * @param buffer        Where to read it into memory.
 174  *
 175  * @return If positive or zero, the number of characters read. If negative, an
 176  *         error occurred.
 177  */
 178 long file_cbfs_read(const struct cbfs_cachenode *file, void *buffer,
 179                     unsigned long maxsize);
 180
 181 #endif /* __CBFS_H */