xref: /openbmc/u-boot/include/environment.h (revision e23b19f4)
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 /* value for the various operations we want to perform on the env */
209 enum env_operation {
210 	ENVOP_GET_CHAR,	/* we want to call the get_char function */
211 	ENVOP_INIT,	/* we want to call the init function */
212 	ENVOP_LOAD,	/* we want to call the load function */
213 	ENVOP_SAVE,	/* we want to call the save function */
214 };
215 
216 struct env_driver {
217 	const char *name;
218 	enum env_location location;
219 
220 	/**
221 	 * get_char() - Read a character from the environment
222 	 *
223 	 * This method is optional. If not provided, a default implementation
224 	 * will read from gd->env_addr.
225 	 *
226 	 * @index: Index of character to read (0=first)
227 	 * @return character read, or -ve on error
228 	 */
229 	int (*get_char)(int index);
230 
231 	/**
232 	 * load() - Load the environment from storage
233 	 *
234 	 * This method is optional. If not provided, no environment will be
235 	 * loaded.
236 	 *
237 	 * @return 0 if OK, -ve on error
238 	 */
239 	int (*load)(void);
240 
241 	/**
242 	 * save() - Save the environment to storage
243 	 *
244 	 * This method is required for 'saveenv' to work.
245 	 *
246 	 * @return 0 if OK, -ve on error
247 	 */
248 	int (*save)(void);
249 
250 	/**
251 	 * init() - Set up the initial pre-relocation environment
252 	 *
253 	 * This method is optional.
254 	 *
255 	 * @return 0 if OK, -ENOENT if no initial environment could be found,
256 	 * other -ve on error
257 	 */
258 	int (*init)(void);
259 };
260 
261 /* Declare a new environment location driver */
262 #define U_BOOT_ENV_LOCATION(__name)					\
263 	ll_entry_declare(struct env_driver, __name, env_driver)
264 
265 /* Declare the name of a location */
266 #ifdef CONFIG_CMD_SAVEENV
267 #define ENV_NAME(_name) .name = _name,
268 #else
269 #define ENV_NAME(_name)
270 #endif
271 
272 #ifdef CONFIG_CMD_SAVEENV
273 #define env_save_ptr(x) x
274 #else
275 #define env_save_ptr(x) NULL
276 #endif
277 
278 extern struct hsearch_data env_htab;
279 
280 /* Function that updates CRC of the enironment */
281 void env_crc_update(void);
282 
283 /* Look up the variable from the default environment */
284 char *env_get_default(const char *name);
285 
286 /* [re]set to the default environment */
287 void set_default_env(const char *s);
288 
289 /* [re]set individual variables to their value in the default environment */
290 int set_default_vars(int nvars, char * const vars[]);
291 
292 /* Import from binary representation into hash table */
293 int env_import(const char *buf, int check);
294 
295 /* Export from hash table into binary representation */
296 int env_export(env_t *env_out);
297 
298 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
299 /* Select and import one of two redundant environments */
300 int env_import_redund(const char *buf1, const char *buf2);
301 #endif
302 
303 /**
304  * env_get_char() - Get a character from the early environment
305  *
306  * This reads from the pre-relocation environemnt
307  *
308  * @index: Index of character to read (0 = first)
309  * @return character read, or -ve on error
310  */
311 int env_get_char(int index);
312 
313 /**
314  * env_load() - Load the environment from storage
315  *
316  * @return 0 if OK, -ve on error
317  */
318 int env_load(void);
319 
320 /**
321  * env_save() - Save the environment to storage
322  *
323  * @return 0 if OK, -ve on error
324  */
325 int env_save(void);
326 
327 #endif /* DO_DEPS_ONLY */
328 
329 #endif /* _ENVIRONMENT_H_ */
330