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 	void *data;
76 	char *name;
77 	u32 type;
78 	u32 data_length;
79 	u32 name_length;
80 	u32 attributes_offset;
81 };
82 
83 /**
84  * file_cbfs_error() - Return a string describing the most recent error
85  * condition.
86  *
87  * @return A pointer to the constant string.
88  */
89 const char *file_cbfs_error(void);
90 
91 /**
92  * cbfs_get_result() - Get the result of the last CBFS operation
93  *
94  *@return last result
95  */
96 enum cbfs_result cbfs_get_result(void);
97 
98 /**
99  * file_cbfs_init() - Initialize the CBFS driver and load metadata into RAM.
100  *
101  * @end_of_rom: Points to the end of the ROM the CBFS should be read from
102  * @return 0 if OK, -ve on error
103  */
104 int file_cbfs_init(ulong end_of_rom);
105 
106 /**
107  * file_cbfs_get_header() - Get the header structure for the current CBFS.
108  *
109  * @return A pointer to the constant structure, or NULL if there is none.
110  */
111 const struct cbfs_header *file_cbfs_get_header(void);
112 
113 /**
114  * file_cbfs_get_first() - Get a handle for the first file in CBFS.
115  *
116  * @return A handle for the first file in CBFS, NULL on error.
117  */
118 const struct cbfs_cachenode *file_cbfs_get_first(void);
119 
120 /**
121  * file_cbfs_get_next() - Get a handle to the file after this one in CBFS.
122  *
123  * @file:		A pointer to the handle to advance.
124  */
125 void file_cbfs_get_next(const struct cbfs_cachenode **file);
126 
127 /**
128  * file_cbfs_find() - Find a file with a particular name in CBFS.
129  *
130  * @name:		The name to search for.
131  *
132  * @return A handle to the file, or NULL on error.
133  */
134 const struct cbfs_cachenode *file_cbfs_find(const char *name);
135 
136 struct cbfs_priv;
137 
138 /**
139  * cbfs_find_file() - Find a file in a given CBFS
140  *
141  * @cbfs: CBFS to look in (use cbfs_init_mem() to set it up)
142  * @name: Filename to look for
143  * @return pointer to CBFS node if found, else NULL
144  */
145 const struct cbfs_cachenode *cbfs_find_file(struct cbfs_priv *cbfs,
146 					    const char *name);
147 
148 /**
149  * cbfs_init_mem() - Set up a new CBFS
150  *
151  * @base: Base address of CBFS
152  * @cbfsp: Returns a pointer to CBFS on success
153  * @return 0 if OK, -ve on error
154  */
155 int cbfs_init_mem(ulong base, struct cbfs_priv **privp);
156 
157 
158 /***************************************************************************/
159 /* All of the functions below can be used without first initializing CBFS. */
160 /***************************************************************************/
161 
162 /**
163  * file_cbfs_find_uncached() - Find a file in CBFS given the end of the ROM
164  *
165  * Note that @node should be declared by the caller. This design is to avoid
166  * the need for allocation here.
167  *
168  * @end_of_rom: Points to the end of the ROM the CBFS should be read from
169  * @name: The name to search for
170  * @node: Returns the contents of the node if found (i.e. copied into *node)
171  * @return 0 on success, -ENOENT if not found, -EFAULT on bad header
172  */
173 int file_cbfs_find_uncached(ulong end_of_rom, const char *name,
174 			    struct cbfs_cachenode *node);
175 
176 /**
177  * file_cbfs_find_uncached_base() - Find a file in CBFS given the base address
178  *
179  * Note that @node should be declared by the caller. This design is to avoid
180  * the need for allocation here.
181  *
182  * @base: Points to the base of the CBFS
183  * @name: The name to search for
184  * @node: Returns the contents of the node if found (i.e. copied into *node)
185  * @return 0 on success, -ENOENT if not found, -EFAULT on bad header
186  */
187 int file_cbfs_find_uncached_base(ulong base, const char *name,
188 				 struct cbfs_cachenode *node);
189 
190 /**
191  * file_cbfs_name() - Get the name of a file in CBFS.
192  *
193  * @file:		The handle to the file.
194  *
195  * @return The name of the file, NULL on error.
196  */
197 const char *file_cbfs_name(const struct cbfs_cachenode *file);
198 
199 /**
200  * file_cbfs_size() - Get the size of a file in CBFS.
201  *
202  * @file:		The handle to the file.
203  *
204  * @return The size of the file, zero on error.
205  */
206 u32 file_cbfs_size(const struct cbfs_cachenode *file);
207 
208 /**
209  * file_cbfs_type() - Get the type of a file in CBFS.
210  *
211  * @file:		The handle to the file.
212  *
213  * @return The type of the file, zero on error.
214  */
215 u32 file_cbfs_type(const struct cbfs_cachenode *file);
216 
217 /**
218  * file_cbfs_read() - Read a file from CBFS into RAM
219  *
220  * @file:		A handle to the file to read.
221  * @buffer:		Where to read it into memory.
222  * @maxsize:		Maximum number of bytes to read
223  *
224  * @return If positive or zero, the number of characters read. If negative, an
225  *	   error occurred.
226  */
227 long file_cbfs_read(const struct cbfs_cachenode *file, void *buffer,
228 		    unsigned long maxsize);
229 
230 #endif /* __CBFS_H */
231