xref: /openbmc/u-boot/include/environment.h (revision 157c74b6)
1 /*
2  * (C) Copyright 2002
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #ifndef _ENVIRONMENT_H_
9 #define _ENVIRONMENT_H_
10 
11 #include <linux/kconfig.h>
12 
13 /**************************************************************************
14  *
15  * The "environment" is stored as a list of '\0' terminated
16  * "name=value" strings. The end of the list is marked by a double
17  * '\0'. New entries are always added at the end. Deleting an entry
18  * shifts the remaining entries to the front. Replacing an entry is a
19  * combination of deleting the old value and adding the new one.
20  *
21  * The environment is preceded by a 32 bit CRC over the data part.
22  *
23  *************************************************************************/
24 
25 #if defined(CONFIG_ENV_IS_IN_FLASH)
26 # ifndef	CONFIG_ENV_ADDR
27 #  define	CONFIG_ENV_ADDR	(CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET)
28 # endif
29 # ifndef	CONFIG_ENV_OFFSET
30 #  define	CONFIG_ENV_OFFSET (CONFIG_ENV_ADDR - CONFIG_SYS_FLASH_BASE)
31 # endif
32 # if !defined(CONFIG_ENV_ADDR_REDUND) && defined(CONFIG_ENV_OFFSET_REDUND)
33 #  define	CONFIG_ENV_ADDR_REDUND	\
34 		(CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET_REDUND)
35 # endif
36 # if defined(CONFIG_ENV_SECT_SIZE) || defined(CONFIG_ENV_SIZE)
37 #  ifndef	CONFIG_ENV_SECT_SIZE
38 #   define	CONFIG_ENV_SECT_SIZE	CONFIG_ENV_SIZE
39 #  endif
40 #  ifndef	CONFIG_ENV_SIZE
41 #   define	CONFIG_ENV_SIZE	CONFIG_ENV_SECT_SIZE
42 #  endif
43 # else
44 #  error "Both CONFIG_ENV_SECT_SIZE and CONFIG_ENV_SIZE undefined"
45 # endif
46 # if defined(CONFIG_ENV_ADDR_REDUND) && !defined(CONFIG_ENV_SIZE_REDUND)
47 #  define CONFIG_ENV_SIZE_REDUND	CONFIG_ENV_SIZE
48 # endif
49 # if	(CONFIG_ENV_ADDR >= CONFIG_SYS_MONITOR_BASE) &&		\
50 	(CONFIG_ENV_ADDR + CONFIG_ENV_SIZE) <=			\
51 	(CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN)
52 #  define ENV_IS_EMBEDDED
53 # endif
54 # if defined(CONFIG_ENV_ADDR_REDUND) || defined(CONFIG_ENV_OFFSET_REDUND)
55 #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT
56 # endif
57 # ifdef CONFIG_ENV_IS_EMBEDDED
58 #  error "do not define CONFIG_ENV_IS_EMBEDDED in your board config"
59 #  error "it is calculated automatically for you"
60 # endif
61 #endif	/* CONFIG_ENV_IS_IN_FLASH */
62 
63 #if defined(CONFIG_ENV_IS_IN_MMC)
64 # ifdef CONFIG_ENV_OFFSET_REDUND
65 #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT
66 # endif
67 #endif
68 
69 #if defined(CONFIG_ENV_IS_IN_NAND)
70 # if defined(CONFIG_ENV_OFFSET_OOB)
71 #  ifdef CONFIG_ENV_OFFSET_REDUND
72 #   error "CONFIG_ENV_OFFSET_REDUND is not supported when CONFIG_ENV_OFFSET_OOB"
73 #   error "is set"
74 #  endif
75 extern unsigned long nand_env_oob_offset;
76 #  define CONFIG_ENV_OFFSET nand_env_oob_offset
77 # else
78 #  ifndef CONFIG_ENV_OFFSET
79 #   error "Need to define CONFIG_ENV_OFFSET when using CONFIG_ENV_IS_IN_NAND"
80 #  endif
81 #  ifdef CONFIG_ENV_OFFSET_REDUND
82 #   define CONFIG_SYS_REDUNDAND_ENVIRONMENT
83 #  endif
84 # endif /* CONFIG_ENV_OFFSET_OOB */
85 # ifndef CONFIG_ENV_SIZE
86 #  error "Need to define CONFIG_ENV_SIZE when using CONFIG_ENV_IS_IN_NAND"
87 # endif
88 #endif /* CONFIG_ENV_IS_IN_NAND */
89 
90 #if defined(CONFIG_ENV_IS_IN_UBI)
91 # ifndef CONFIG_ENV_UBI_PART
92 #  error "Need to define CONFIG_ENV_UBI_PART when using CONFIG_ENV_IS_IN_UBI"
93 # endif
94 # ifndef CONFIG_ENV_UBI_VOLUME
95 #  error "Need to define CONFIG_ENV_UBI_VOLUME when using CONFIG_ENV_IS_IN_UBI"
96 # endif
97 # if defined(CONFIG_ENV_UBI_VOLUME_REDUND)
98 #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT
99 # endif
100 # ifndef CONFIG_ENV_SIZE
101 #  error "Need to define CONFIG_ENV_SIZE when using CONFIG_ENV_IS_IN_UBI"
102 # endif
103 # ifndef CONFIG_CMD_UBI
104 #  error "Need to define CONFIG_CMD_UBI when using CONFIG_ENV_IS_IN_UBI"
105 # endif
106 #endif /* CONFIG_ENV_IS_IN_UBI */
107 
108 /* Embedded env is only supported for some flash types */
109 #ifdef CONFIG_ENV_IS_EMBEDDED
110 # if	!defined(CONFIG_ENV_IS_IN_FLASH)	&& \
111 	!defined(CONFIG_ENV_IS_IN_NAND)		&& \
112 	!defined(CONFIG_ENV_IS_IN_ONENAND)	&& \
113 	!defined(CONFIG_ENV_IS_IN_SPI_FLASH)
114 #  error "CONFIG_ENV_IS_EMBEDDED not supported for your flash type"
115 # endif
116 #endif
117 
118 /*
119  * For the flash types where embedded env is supported, but it cannot be
120  * calculated automatically (i.e. NAND), take the board opt-in.
121  */
122 #if defined(CONFIG_ENV_IS_EMBEDDED) && !defined(ENV_IS_EMBEDDED)
123 # define ENV_IS_EMBEDDED
124 #endif
125 
126 /* The build system likes to know if the env is embedded */
127 #ifdef DO_DEPS_ONLY
128 # ifdef ENV_IS_EMBEDDED
129 #  ifndef CONFIG_ENV_IS_EMBEDDED
130 #   define CONFIG_ENV_IS_EMBEDDED
131 #  endif
132 # endif
133 #endif
134 
135 #include "compiler.h"
136 
137 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
138 # define ENV_HEADER_SIZE	(sizeof(uint32_t) + 1)
139 
140 # define ACTIVE_FLAG   1
141 # define OBSOLETE_FLAG 0
142 #else
143 # define ENV_HEADER_SIZE	(sizeof(uint32_t))
144 #endif
145 
146 #define ENV_SIZE (CONFIG_ENV_SIZE - ENV_HEADER_SIZE)
147 
148 typedef struct environment_s {
149 	uint32_t	crc;		/* CRC32 over data bytes	*/
150 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
151 	unsigned char	flags;		/* active/obsolete flags	*/
152 #endif
153 	unsigned char	data[ENV_SIZE]; /* Environment data		*/
154 } env_t;
155 
156 #ifdef ENV_IS_EMBEDDED
157 extern env_t environment;
158 #endif /* ENV_IS_EMBEDDED */
159 
160 extern const unsigned char default_environment[];
161 extern env_t *env_ptr;
162 
163 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
164 extern void env_reloc(void);
165 #endif
166 
167 #ifdef CONFIG_ENV_IS_IN_MMC
168 #include <mmc.h>
169 
170 extern int mmc_get_env_addr(struct mmc *mmc, int copy, u32 *env_addr);
171 # ifdef CONFIG_SYS_MMC_ENV_PART
172 extern uint mmc_get_env_part(struct mmc *mmc);
173 # endif
174 #endif
175 
176 #ifndef DO_DEPS_ONLY
177 
178 #include <env_attr.h>
179 #include <env_callback.h>
180 #include <env_flags.h>
181 #include <search.h>
182 
183 /* Value for environment validity */
184 enum env_valid {
185 	ENV_INVALID,	/* No valid environment */
186 	ENV_VALID,	/* First or only environment is valid */
187 	ENV_REDUND,	/* Redundant environment is valid */
188 };
189 
190 enum env_location {
191 	ENVL_EEPROM,
192 	ENVL_EXT4,
193 	ENVL_FAT,
194 	ENVL_FLASH,
195 	ENVL_MMC,
196 	ENVL_NAND,
197 	ENVL_NVRAM,
198 	ENVL_ONENAND,
199 	ENVL_REMOTE,
200 	ENVL_SPI_FLASH,
201 	ENVL_UBI,
202 	ENVL_NOWHERE,
203 
204 	ENVL_COUNT,
205 	ENVL_UNKNOWN,
206 };
207 
208 struct env_driver {
209 	const char *name;
210 	enum env_location location;
211 
212 	/**
213 	 * get_char() - Read a character from the environment
214 	 *
215 	 * This method is optional. If not provided, a default implementation
216 	 * will read from gd->env_addr.
217 	 *
218 	 * @index: Index of character to read (0=first)
219 	 * @return character read, or -ve on error
220 	 */
221 	int (*get_char)(int index);
222 
223 	/**
224 	 * load() - Load the environment from storage
225 	 *
226 	 * This method is optional. If not provided, no environment will be
227 	 * loaded.
228 	 *
229 	 * @return 0 if OK, -ve on error
230 	 */
231 	int (*load)(void);
232 
233 	/**
234 	 * save() - Save the environment to storage
235 	 *
236 	 * This method is required for 'saveenv' to work.
237 	 *
238 	 * @return 0 if OK, -ve on error
239 	 */
240 	int (*save)(void);
241 
242 	/**
243 	 * init() - Set up the initial pre-relocation environment
244 	 *
245 	 * This method is optional.
246 	 *
247 	 * @return 0 if OK, -ENOENT if no initial environment could be found,
248 	 * other -ve on error
249 	 */
250 	int (*init)(void);
251 };
252 
253 /* Declare a new environment location driver */
254 #define U_BOOT_ENV_LOCATION(__name)					\
255 	ll_entry_declare(struct env_driver, __name, env_driver)
256 
257 /* Declare the name of a location */
258 #ifdef CONFIG_CMD_SAVEENV
259 #define ENV_NAME(_name) .name = _name,
260 #else
261 #define ENV_NAME(_name)
262 #endif
263 
264 #ifdef CONFIG_CMD_SAVEENV
265 #define env_save_ptr(x) x
266 #else
267 #define env_save_ptr(x) NULL
268 #endif
269 
270 extern struct hsearch_data env_htab;
271 
272 /* Function that updates CRC of the enironment */
273 void env_crc_update(void);
274 
275 /* Look up the variable from the default environment */
276 char *env_get_default(const char *name);
277 
278 /* [re]set to the default environment */
279 void set_default_env(const char *s);
280 
281 /* [re]set individual variables to their value in the default environment */
282 int set_default_vars(int nvars, char * const vars[]);
283 
284 /* Import from binary representation into hash table */
285 int env_import(const char *buf, int check);
286 
287 /* Export from hash table into binary representation */
288 int env_export(env_t *env_out);
289 
290 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
291 /* Select and import one of two redundant environments */
292 int env_import_redund(const char *buf1, const char *buf2);
293 #endif
294 
295 /**
296  * env_driver_lookup_default() - Look up the default environment driver
297  *
298  * @return pointer to driver, or NULL if none (which should not happen)
299  */
300 struct env_driver *env_driver_lookup_default(void);
301 
302 /**
303  * env_get_char() - Get a character from the early environment
304  *
305  * This reads from the pre-relocation environemnt
306  *
307  * @index: Index of character to read (0 = first)
308  * @return character read, or -ve on error
309  */
310 int env_get_char(int index);
311 
312 /**
313  * env_load() - Load the environment from storage
314  *
315  * @return 0 if OK, -ve on error
316  */
317 int env_load(void);
318 
319 /**
320  * env_save() - Save the environment to storage
321  *
322  * @return 0 if OK, -ve on error
323  */
324 int env_save(void);
325 
326 #endif /* DO_DEPS_ONLY */
327 
328 #endif /* _ENVIRONMENT_H_ */
329