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