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
12struct cbfs_priv;
13
14enum cbfs_result {
15	CBFS_SUCCESS = 0,
16	CBFS_NOT_INITIALIZED,
17	CBFS_BAD_HEADER,
18	CBFS_BAD_FILE,
19	CBFS_FILE_NOT_FOUND
20};
21
22enum cbfs_filetype {
23	CBFS_TYPE_BOOTBLOCK = 0x01,
24	CBFS_TYPE_CBFSHEADER = 0x02,
25	CBFS_TYPE_LEGACY_STAGE = 0x10,
26	CBFS_TYPE_PAYLOAD = 0x20,
27	CBFS_TYPE_SELF = CBFS_TYPE_PAYLOAD,
28
29	CBFS_TYPE_FIT = 0x21,
30	CBFS_TYPE_OPTIONROM = 0x30,
31	CBFS_TYPE_BOOTSPLASH = 0x40,
32	CBFS_TYPE_RAW = 0x50,
33	CBFS_TYPE_VSA = 0x51,
34	CBFS_TYPE_MBI = 0x52,
35	CBFS_TYPE_MICROCODE = 0x53,
36	CBFS_TYPE_FSP = 0x60,
37	CBFS_TYPE_MRC = 0x61,
38	CBFS_TYPE_MMA = 0x62,
39	CBFS_TYPE_EFI = 0x63,
40	CBFS_TYPE_STRUCT = 0x70,
41	CBFS_TYPE_CMOS_DEFAULT = 0xaa,
42	CBFS_TYPE_SPD = 0xab,
43	CBFS_TYPE_MRC_CACHE = 0xac,
44	CBFS_TYPE_CMOS_LAYOUT = 0x01aa
45};
46
47enum {
48	CBFS_HEADER_MAGIC	= 0x4f524243,
49	CBFS_SIZE_UNKNOWN	= 0xffffffff,
50	CBFS_ALIGN_SIZE		= 0x40,
51};
52
53/**
54 * struct cbfs_header - header at the start of a CBFS region
55 *
56 * All fields use big-endian format.
57 *
58 * @magic: Magic number (CBFS_HEADER_MAGIC)
59 */
60struct cbfs_header {
61	u32 magic;
62	u32 version;
63	u32 rom_size;
64	u32 boot_block_size;
65	u32 align;
66	u32 offset;
67	u32 pad[2];
68} __packed;
69
70struct cbfs_fileheader {
71	u8 magic[8];
72	u32 len;
73	u32 type;
74	/* offset to struct cbfs_file_attribute or 0 */
75	u32 attributes_offset;
76	u32 offset;
77	char filename[];
78} __packed;
79
80/**
81 * These are standard values for the known compression alogrithms that coreboot
82 * knows about for stages and payloads.  Of course, other CBFS users can use
83 * whatever values they want, as long as they understand them.
84 */
85#define CBFS_COMPRESS_NONE  0
86#define CBFS_COMPRESS_LZMA  1
87#define CBFS_COMPRESS_LZ4   2
88
89/*
90 * Depending on how the header was initialized, it may be backed with 0x00 or
91 * 0xff, so support both
92 */
93#define CBFS_FILE_ATTR_TAG_UNUSED 0
94#define CBFS_FILE_ATTR_TAG_UNUSED2 0xffffffff
95#define CBFS_FILE_ATTR_TAG_COMPRESSION 0x42435a4c
96#define CBFS_FILE_ATTR_TAG_HASH 0x68736148
97
98/*
99 * The common fields of extended cbfs file attributes. Attributes are expected
100 * to start with tag/len, then append their specific fields
101 */
102struct cbfs_file_attribute {
103	u32 tag;
104	/* len covers the whole structure, incl. tag and len */
105	u32 len;
106	u8 data[0];
107} __packed;
108
109struct cbfs_file_attr_compression {
110	u32 tag;
111	u32 len;
112	/* whole file compression format. 0 if no compression. */
113	u32 compression;
114	u32 decompressed_size;
115} __packed;
116
117struct cbfs_file_attr_hash {
118	u32 tag;
119	u32 len;
120	u32 hash_type;
121	/* hash_data is len - sizeof(struct) bytes */
122	u8  hash_data[];
123} __packed;
124
125/*** Component sub-headers ***/
126
127/* Following are component sub-headers for the "standard" component types */
128
129/**
130 * struct cbfs_stage - sub-header for stage components
131 *
132 * Stages are loaded by coreboot during the normal boot process
133 */
134struct cbfs_stage {
135	u32 compression;  /** Compression type */
136	u64 entry;  /** entry point */
137	u64 load;   /** Where to load in memory */
138	u32 len;          /** length of data to load */
139	u32 memlen;	   /** total length of object in memory */
140} __packed;
141
142/**
143 * struct cbfs_payload_segment - sub-header for payload components
144 *
145 * Payloads are loaded by coreboot at the end of the boot process
146 */
147struct cbfs_payload_segment {
148	u32 type;
149	u32 compression;
150	u32 offset;
151	u64 load_addr;
152	u32 len;
153	u32 mem_len;
154} __packed;
155
156struct cbfs_payload {
157	struct cbfs_payload_segment segments;
158};
159
160#define PAYLOAD_SEGMENT_CODE   0x45444F43
161#define PAYLOAD_SEGMENT_DATA   0x41544144
162#define PAYLOAD_SEGMENT_BSS    0x20535342
163#define PAYLOAD_SEGMENT_PARAMS 0x41524150
164#define PAYLOAD_SEGMENT_ENTRY  0x52544E45
165
166struct cbfs_cachenode {
167	struct cbfs_cachenode *next;
168	void *data;
169	char *name;
170	u32 type;
171	u32 data_length;
172	u32 name_length;
173	u32 attr_offset;
174	u32 comp_algo;
175	u32 decomp_size;
176};
177
178/**
179 * file_cbfs_error() - Return a string describing the most recent error
180 * condition.
181 *
182 * Return: A pointer to the constant string.
183 */
184const char *file_cbfs_error(void);
185
186/**
187 * cbfs_get_result() - Get the result of the last CBFS operation
188 *
189 *Return: last result
190 */
191enum cbfs_result cbfs_get_result(void);
192
193/**
194 * file_cbfs_init() - Initialize the CBFS driver and load metadata into RAM.
195 *
196 * @end_of_rom: Points to the end of the ROM the CBFS should be read from
197 * Return: 0 if OK, -ve on error
198 */
199int file_cbfs_init(ulong end_of_rom);
200
201/**
202 * file_cbfs_get_header() - Get the header structure for the current CBFS.
203 *
204 * Return: A pointer to the constant structure, or NULL if there is none.
205 */
206const struct cbfs_header *file_cbfs_get_header(void);
207
208/**
209 * cbfs_get_first() - Get the first file in a CBFS
210 *
211 * Return: pointer to first file, or NULL if it is empty
212 */
213const struct cbfs_cachenode *cbfs_get_first(const struct cbfs_priv *priv);
214
215/**
216 * cbfs_get_next() - Get the next file in a CBFS
217 *
218 * @filep: Pointer to current file; updated to point to the next file, if any,
219 *	else NULL
220 */
221void cbfs_get_next(const struct cbfs_cachenode **filep);
222
223/**
224 * file_cbfs_get_first() - Get a handle for the first file in CBFS.
225 *
226 * Return: A handle for the first file in CBFS, NULL on error.
227 */
228const struct cbfs_cachenode *file_cbfs_get_first(void);
229
230/**
231 * file_cbfs_get_next() - Get a handle to the file after this one in CBFS.
232 *
233 * @file:		A pointer to the handle to advance.
234 */
235void file_cbfs_get_next(const struct cbfs_cachenode **file);
236
237/**
238 * file_cbfs_find() - Find a file with a particular name in CBFS.
239 *
240 * @name:		The name to search for.
241 *
242 * Return: A handle to the file, or NULL on error.
243 */
244const struct cbfs_cachenode *file_cbfs_find(const char *name);
245
246/**
247 * cbfs_find_file() - Find a file in a given CBFS
248 *
249 * @cbfs: CBFS to look in (use cbfs_init_mem() to set it up)
250 * @name: Filename to look for
251 * Return: pointer to CBFS node if found, else NULL
252 */
253const struct cbfs_cachenode *cbfs_find_file(struct cbfs_priv *cbfs,
254					    const char *name);
255
256/**
257 * cbfs_init_mem() - Set up a new CBFS
258 *
259 * @base: Base address of CBFS
260 * @size: Size of CBFS if known, else CBFS_SIZE_UNKNOWN
261 * @require_header: true to read a header at the start, false to not require one
262 * @cbfsp: Returns a pointer to CBFS on success
263 * Return: 0 if OK, -ve on error
264 */
265int cbfs_init_mem(ulong base, ulong size, bool require_hdr,
266		  struct cbfs_priv **privp);
267
268/***************************************************************************/
269/* All of the functions below can be used without first initializing CBFS. */
270/***************************************************************************/
271
272/**
273 * file_cbfs_find_uncached() - Find a file in CBFS given the end of the ROM
274 *
275 * Note that @node should be declared by the caller. This design is to avoid
276 * the need for allocation here.
277 *
278 * @end_of_rom: Points to the end of the ROM the CBFS should be read from
279 * @name: The name to search for
280 * @node: Returns the contents of the node if found (i.e. copied into *node)
281 * Return: 0 on success, -ENOENT if not found, -EFAULT on bad header
282 */
283int file_cbfs_find_uncached(ulong end_of_rom, const char *name,
284			    struct cbfs_cachenode *node);
285
286/**
287 * file_cbfs_find_uncached_base() - Find a file in CBFS given the base address
288 *
289 * Note that @node should be declared by the caller. This design is to avoid
290 * the need for allocation here.
291 *
292 * @base: Points to the base of the CBFS
293 * @name: The name to search for
294 * @node: Returns the contents of the node if found (i.e. copied into *node)
295 * Return: 0 on success, -ENOENT if not found, -EFAULT on bad header
296 */
297int file_cbfs_find_uncached_base(ulong base, const char *name,
298				 struct cbfs_cachenode *node);
299
300/**
301 * file_cbfs_name() - Get the name of a file in CBFS.
302 *
303 * @file:		The handle to the file.
304 *
305 * Return: The name of the file, NULL on error.
306 */
307const char *file_cbfs_name(const struct cbfs_cachenode *file);
308
309/**
310 * file_cbfs_size() - Get the size of a file in CBFS.
311 *
312 * @file:		The handle to the file.
313 *
314 * Return: The size of the file, zero on error.
315 */
316u32 file_cbfs_size(const struct cbfs_cachenode *file);
317
318/**
319 * file_cbfs_type() - Get the type of a file in CBFS.
320 *
321 * @file:		The handle to the file.
322 *
323 * Return: The type of the file, zero on error.
324 */
325u32 file_cbfs_type(const struct cbfs_cachenode *file);
326
327/**
328 * file_cbfs_read() - Read a file from CBFS into RAM
329 *
330 * @file:		A handle to the file to read.
331 * @buffer:		Where to read it into memory.
332 * @maxsize:		Maximum number of bytes to read
333 *
334 * Return: If positive or zero, the number of characters read. If negative, an
335 *	   error occurred.
336 */
337long file_cbfs_read(const struct cbfs_cachenode *file, void *buffer,
338		    unsigned long maxsize);
339
340#endif /* __CBFS_H */
341