1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * Common environment functions and definitions
5 * (C) Copyright 2000-2009
6 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
13 #include <linux/types.h>
17 /* Value for environment validity */
19 ENV_INVALID, /* No valid environment */
20 ENV_VALID, /* First or only environment is valid */
21 ENV_REDUND, /* Redundant environment is valid */
24 /** enum env_op - environment callback operation */
31 /** struct env_clbk_tbl - declares a new callback */
33 const char *name; /* Callback name */
34 int (*callback)(const char *name, const char *value, enum env_op op,
39 * Define a callback that can be associated with variables.
40 * when associated through the ".callbacks" environment variable, the callback
41 * will be executed any time the variable is inserted, overwritten, or deleted.
43 * For SPL these are silently dropped to reduce code size, since environment
44 * callbacks are not supported with SPL.
46 #ifdef CONFIG_SPL_BUILD
47 #define U_BOOT_ENV_CALLBACK(name, callback) \
48 static inline __maybe_unused void _u_boot_env_noop_##name(void) \
53 #define U_BOOT_ENV_CALLBACK(name, callback) \
54 ll_entry_declare(struct env_clbk_tbl, name, env_clbk) = \
59 * env_get_id() - Gets a sequence number for the environment
61 * This value increments every time the environment changes, so can be used an
62 * an indication of this
64 * @return environment ID
69 * env_init() - Set up the pre-relocation environment
71 * This locates the environment or uses the default if nothing is available.
72 * This must be called before env_get() will work.
74 * @return 0 if OK, -ENODEV if no environment drivers are enabled
79 * env_relocate() - Set up the post-relocation environment
81 * This loads the environment into RAM so that it can be modified. This is
82 * called after relocation, before the environment is used
84 void env_relocate(void);
87 * env_match() - Match a name / name=value pair
89 * This is used prior to relocation for finding envrionment variables
91 * @name: A simple 'name', or a 'name=value' pair.
92 * @index: The environment index for a 'name2=value2' pair.
93 * @return index for the value if the names match, else -1.
95 int env_match(unsigned char *name, int index);
98 * env_get() - Look up the value of an environment variable
100 * In U-Boot proper this can be called before relocation (which is when the
101 * environment is loaded from storage, i.e. GD_FLG_ENV_READY is 0). In that
102 * case this function calls env_get_f().
104 * @varname: Variable to look up
105 * @return value of variable, or NULL if not found
107 char *env_get(const char *varname);
110 * env_get_f() - Look up the value of an environment variable (early)
112 * This function is called from env_get() if the environment has not been
113 * loaded yet (GD_FLG_ENV_READY flag is 0). Some environment locations will
114 * support reading the value (slowly) and some will not.
116 * @varname: Variable to look up
117 * @return value of variable, or NULL if not found
119 int env_get_f(const char *name, char *buf, unsigned int len);
122 * env_get_yesno() - Read an environment variable as a boolean
124 * @return 1 if yes/true (Y/y/T/t), -1 if variable does not exist (i.e. default
125 * to true), 0 if otherwise
127 int env_get_yesno(const char *var);
130 * env_set() - set an environment variable
132 * This sets or deletes the value of an environment variable. For setting the
133 * value the variable is created if it does not already exist.
135 * @varname: Variable to adjust
136 * @value: Value to set for the variable, or NULL or "" to delete the variable
137 * @return 0 if OK, 1 on error
139 int env_set(const char *varname, const char *value);
142 * env_get_ulong() - Return an environment variable as an integer value
144 * Most U-Boot environment variables store hex values. For those which store
145 * (e.g.) base-10 integers, this function can be used to read the value.
147 * @name: Variable to look up
148 * @base: Base to use (e.g. 10 for base 10, 2 for binary)
149 * @default_val: Default value to return if no value is found
150 * @return the value found, or @default_val if none
152 ulong env_get_ulong(const char *name, int base, ulong default_val);
155 * env_set_ulong() - set an environment variable to an integer
157 * @varname: Variable to adjust
158 * @value: Value to set for the variable (will be converted to a string)
159 * @return 0 if OK, 1 on error
161 int env_set_ulong(const char *varname, ulong value);
164 * env_get_hex() - Return an environment variable as a hex value
166 * Decode an environment as a hex number (it may or may not have a 0x
167 * prefix). If the environment variable cannot be found, or does not start
168 * with hex digits, the default value is returned.
170 * @varname: Variable to decode
171 * @default_val: Value to return on error
173 ulong env_get_hex(const char *varname, ulong default_val);
176 * env_set_hex() - set an environment variable to a hex value
178 * @varname: Variable to adjust
179 * @value: Value to set for the variable (will be converted to a hex string)
180 * @return 0 if OK, 1 on error
182 int env_set_hex(const char *varname, ulong value);
185 * env_set_addr - Set an environment variable to an address in hex
187 * @varname: Environment variable to set
188 * @addr: Value to set it to
189 * @return 0 if ok, 1 on error
191 static inline int env_set_addr(const char *varname, const void *addr)
193 return env_set_hex(varname, (ulong)addr);
197 * env_complete() - return an auto-complete for environment variables
199 * @var: partial name to auto-complete
200 * @maxv: Maximum number of matches to return
201 * @cmdv: Returns a list of possible matches
202 * @maxsz: Size of buffer to use for matches
203 * @buf: Buffer to use for matches
204 * @dollar_comp: non-zero to wrap each match in ${...}
205 * @return number of matches found (in @cmdv)
207 int env_complete(char *var, int maxv, char *cmdv[], int maxsz, char *buf,
211 * eth_env_get_enetaddr() - Get an ethernet address from the environmnet
213 * @name: Environment variable to get (e.g. "ethaddr")
214 * @enetaddr: Place to put MAC address (6 bytes)
215 * @return 0 if OK, 1 on error
217 int eth_env_get_enetaddr(const char *name, uint8_t *enetaddr);
220 * eth_env_set_enetaddr() - Set an ethernet address in the environmnet
222 * @name: Environment variable to set (e.g. "ethaddr")
223 * @enetaddr: Pointer to MAC address to put into the variable (6 bytes)
224 * @return 0 if OK, 1 on error
226 int eth_env_set_enetaddr(const char *name, const uint8_t *enetaddr);
229 * env_fix_drivers() - Updates envdriver as per relocation
231 void env_fix_drivers(void);
234 * env_set_default_vars() - reset variables to their default value
236 * This resets individual variables to their value in the default environment
238 * @nvars: Number of variables to set/reset
239 * @vars: List of variables to set/reset
240 * @flags: Flags controlling matching (H_... - see search.h)
242 int env_set_default_vars(int nvars, char *const vars[], int flags);
245 * env_load() - Load the environment from storage
247 * @return 0 if OK, -ve on error
252 * env_save() - Save the environment to storage
254 * @return 0 if OK, -ve on error
259 * env_erase() - Erase the environment on storage
261 * @return 0 if OK, -ve on error
266 * env_import() - Import from a binary representation into hash table
268 * This imports the environment from a buffer. The format for each variable is
269 * var=value\0 with a double \0 at the end of the buffer.
271 * @buf: Buffer containing the environment (struct environemnt_s *)
272 * @check: non-zero to check the CRC at the start of the environment, 0 to
274 * @return 0 if imported successfully, -ENOMSG if the CRC was bad, -EIO if
275 * something else went wrong
277 int env_import(const char *buf, int check);
280 * env_export() - Export the environment to a buffer
282 * Export from hash table into binary representation
284 * @env_out: Buffer to contain the environment (must be large enough!)
285 * @return 0 if OK, 1 on error
287 int env_export(struct environment_s *env_out);
290 * env_import_redund() - Select and import one of two redundant environments
292 * @buf1: First environment (struct environemnt_s *)
293 * @buf1_read_fail: 0 if buf1 is valid, non-zero if invalid
294 * @buf2: Second environment (struct environemnt_s *)
295 * @buf2_read_fail: 0 if buf2 is valid, non-zero if invalid
296 * @return 0 if OK, -EIO if no environment is valid, -ENOMSG if the CRC was bad
298 int env_import_redund(const char *buf1, int buf1_read_fail,
299 const char *buf2, int buf2_read_fail);
302 * env_get_default() - Look up a variable from the default environment
304 * @name: Variable to look up
305 * @return value if found, NULL if not found in default environment
307 char *env_get_default(const char *name);
309 /* [re]set to the default environment */
310 void env_set_default(const char *s, int flags);
313 * env_get_char() - Get a character from the early environment
315 * This reads from the pre-relocation environment
317 * @index: Index of character to read (0 = first)
318 * @return character read, or -ve on error
320 int env_get_char(int index);
323 * env_reloc() - Relocate the 'env' sub-commands
325 * This is used for those unfortunate archs with crappy toolchains
327 void env_reloc(void);