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.
14 #include <linux/types.h>
18 /* Value for environment validity */
20 ENV_INVALID, /* No valid environment */
21 ENV_VALID, /* First or only environment is valid */
22 ENV_REDUND, /* Redundant environment is valid */
25 /** enum env_op - environment callback operation */
32 /** struct env_clbk_tbl - declares a new callback */
34 const char *name; /* Callback name */
35 int (*callback)(const char *name, const char *value, enum env_op op,
40 * Define a callback that can be associated with variables.
41 * when associated through the ".callbacks" environment variable, the callback
42 * will be executed any time the variable is inserted, overwritten, or deleted.
44 * For SPL these are silently dropped to reduce code size, since environment
45 * callbacks are not supported with SPL.
47 #ifdef CONFIG_SPL_BUILD
48 #define U_BOOT_ENV_CALLBACK(name, callback) \
49 static inline __maybe_unused void _u_boot_env_noop_##name(void) \
54 #define U_BOOT_ENV_CALLBACK(name, callback) \
55 ll_entry_declare(struct env_clbk_tbl, name, env_clbk) = \
59 /** enum env_redund_flags - Flags for the redundand_environment */
60 enum env_redund_flags {
61 ENV_REDUND_OBSOLETE = 0,
62 ENV_REDUND_ACTIVE = 1,
66 * env_get_id() - Gets a sequence number for the environment
68 * This value increments every time the environment changes, so can be used an
69 * an indication of this
71 * @return environment ID
76 * env_init() - Set up the pre-relocation environment
78 * This locates the environment or uses the default if nothing is available.
79 * This must be called before env_get() will work.
81 * @return 0 if OK, -ENODEV if no environment drivers are enabled
86 * env_relocate() - Set up the post-relocation environment
88 * This loads the environment into RAM so that it can be modified. This is
89 * called after relocation, before the environment is used
91 void env_relocate(void);
94 * env_match() - Match a name / name=value pair
96 * This is used prior to relocation for finding envrionment variables
98 * @name: A simple 'name', or a 'name=value' pair.
99 * @index: The environment index for a 'name2=value2' pair.
100 * @return index for the value if the names match, else -1.
102 int env_match(unsigned char *name, int index);
105 * env_get() - Look up the value of an environment variable
107 * In U-Boot proper this can be called before relocation (which is when the
108 * environment is loaded from storage, i.e. GD_FLG_ENV_READY is 0). In that
109 * case this function calls env_get_f().
111 * @varname: Variable to look up
112 * @return value of variable, or NULL if not found
114 char *env_get(const char *varname);
117 * Like env_get, but prints an error if envvar isn't defined in the
118 * environment. It always returns what env_get does, so it can be used in
119 * place of env_get without changing error handling otherwise.
121 * @varname: Variable to look up
122 * @return value of variable, or NULL if not found
124 char *from_env(const char *envvar);
127 * env_get_f() - Look up the value of an environment variable (early)
129 * This function is called from env_get() if the environment has not been
130 * loaded yet (GD_FLG_ENV_READY flag is 0). Some environment locations will
131 * support reading the value (slowly) and some will not.
133 * @varname: Variable to look up
134 * @return number of bytes written into @buf, excluding the terminating
135 * NULL-byte if there was enough space in @buf, and including the
136 * terminating NULL-byte if there wasn't enough space, or -1 if the
137 * variable is not found
139 int env_get_f(const char *name, char *buf, unsigned int len);
142 * env_get_yesno() - Read an environment variable as a boolean
144 * @return 1 if yes/true (Y/y/T/t), -1 if variable does not exist (i.e. default
145 * to true), 0 if otherwise
147 int env_get_yesno(const char *var);
150 * env_set() - set an environment variable
152 * This sets or deletes the value of an environment variable. For setting the
153 * value the variable is created if it does not already exist.
155 * @varname: Variable to adjust
156 * @value: Value to set for the variable, or NULL or "" to delete the variable
157 * @return 0 if OK, 1 on error
159 int env_set(const char *varname, const char *value);
162 * env_get_ulong() - Return an environment variable as an integer value
164 * Most U-Boot environment variables store hex values. For those which store
165 * (e.g.) base-10 integers, this function can be used to read the value.
167 * @name: Variable to look up
168 * @base: Base to use (e.g. 10 for base 10, 2 for binary)
169 * @default_val: Default value to return if no value is found
170 * @return the value found, or @default_val if none
172 ulong env_get_ulong(const char *name, int base, ulong default_val);
175 * env_set_ulong() - set an environment variable to an integer
177 * @varname: Variable to adjust
178 * @value: Value to set for the variable (will be converted to a string)
179 * @return 0 if OK, 1 on error
181 int env_set_ulong(const char *varname, ulong value);
184 * env_get_hex() - Return an environment variable as a hex value
186 * Decode an environment as a hex number (it may or may not have a 0x
187 * prefix). If the environment variable cannot be found, or does not start
188 * with hex digits, the default value is returned.
190 * @varname: Variable to decode
191 * @default_val: Value to return on error
193 ulong env_get_hex(const char *varname, ulong default_val);
196 * env_set_hex() - set an environment variable to a hex value
198 * @varname: Variable to adjust
199 * @value: Value to set for the variable (will be converted to a hex string)
200 * @return 0 if OK, 1 on error
202 int env_set_hex(const char *varname, ulong value);
205 * env_set_addr - Set an environment variable to an address in hex
207 * @varname: Environment variable to set
208 * @addr: Value to set it to
209 * @return 0 if ok, 1 on error
211 static inline int env_set_addr(const char *varname, const void *addr)
213 return env_set_hex(varname, (ulong)addr);
217 * env_complete() - return an auto-complete for environment variables
219 * @var: partial name to auto-complete
220 * @maxv: Maximum number of matches to return
221 * @cmdv: Returns a list of possible matches
222 * @maxsz: Size of buffer to use for matches
223 * @buf: Buffer to use for matches
224 * @dollar_comp: non-zero to wrap each match in ${...}
225 * @return number of matches found (in @cmdv)
227 int env_complete(char *var, int maxv, char *cmdv[], int maxsz, char *buf,
231 * eth_env_get_enetaddr() - Get an ethernet address from the environmnet
233 * @name: Environment variable to get (e.g. "ethaddr")
234 * @enetaddr: Place to put MAC address (6 bytes)
235 * @return 0 if OK, 1 on error
237 int eth_env_get_enetaddr(const char *name, uint8_t *enetaddr);
240 * eth_env_set_enetaddr() - Set an ethernet address in the environmnet
242 * @name: Environment variable to set (e.g. "ethaddr")
243 * @enetaddr: Pointer to MAC address to put into the variable (6 bytes)
244 * @return 0 if OK, 1 on error
246 int eth_env_set_enetaddr(const char *name, const uint8_t *enetaddr);
249 * env_fix_drivers() - Updates envdriver as per relocation
251 void env_fix_drivers(void);
254 * env_set_default_vars() - reset variables to their default value
256 * This resets individual variables to their value in the default environment
258 * @nvars: Number of variables to set/reset
259 * @vars: List of variables to set/reset
260 * @flags: Flags controlling matching (H_... - see search.h)
262 int env_set_default_vars(int nvars, char *const vars[], int flags);
265 * env_load() - Load the environment from storage
267 * @return 0 if OK, -ve on error
272 * env_reload() - Re-Load the environment from current storage
274 * @return 0 if OK, -ve on error
276 int env_reload(void);
279 * env_save() - Save the environment to storage
281 * @return 0 if OK, -ve on error
286 * env_erase() - Erase the environment on storage
288 * @return 0 if OK, -ve on error
293 * env_select() - Select the environment storage
295 * @return 0 if OK, -ve on error
297 int env_select(const char *name);
300 * env_import() - Import from a binary representation into hash table
302 * This imports the environment from a buffer. The format for each variable is
303 * var=value\0 with a double \0 at the end of the buffer.
305 * @buf: Buffer containing the environment (struct environemnt_s *)
306 * @check: non-zero to check the CRC at the start of the environment, 0 to
308 * @flags: Flags controlling matching (H_... - see search.h)
309 * @return 0 if imported successfully, -ENOMSG if the CRC was bad, -EIO if
310 * something else went wrong
312 int env_import(const char *buf, int check, int flags);
315 * env_export() - Export the environment to a buffer
317 * Export from hash table into binary representation
319 * @env_out: Buffer to contain the environment (must be large enough!)
320 * @return 0 if OK, 1 on error
322 int env_export(struct environment_s *env_out);
325 * env_check_redund() - check the two redundant environments
326 * and find out, which is the valid one.
328 * @buf1: First environment (struct environemnt_s *)
329 * @buf1_read_fail: 0 if buf1 is valid, non-zero if invalid
330 * @buf2: Second environment (struct environemnt_s *)
331 * @buf2_read_fail: 0 if buf2 is valid, non-zero if invalid
333 * -EIO if no environment is valid,
334 * -ENOMSG if the CRC was bad
337 int env_check_redund(const char *buf1, int buf1_read_fail,
338 const char *buf2, int buf2_read_fail);
341 * env_import_redund() - Select and import one of two redundant environments
343 * @buf1: First environment (struct environemnt_s *)
344 * @buf1_read_fail: 0 if buf1 is valid, non-zero if invalid
345 * @buf2: Second environment (struct environemnt_s *)
346 * @buf2_read_fail: 0 if buf2 is valid, non-zero if invalid
347 * @flags: Flags controlling matching (H_... - see search.h)
348 * @return 0 if OK, -EIO if no environment is valid, -ENOMSG if the CRC was bad
350 int env_import_redund(const char *buf1, int buf1_read_fail,
351 const char *buf2, int buf2_read_fail,
355 * env_get_default() - Look up a variable from the default environment
357 * @name: Variable to look up
358 * @return value if found, NULL if not found in default environment
360 char *env_get_default(const char *name);
362 /* [re]set to the default environment */
363 void env_set_default(const char *s, int flags);
366 * env_get_char() - Get a character from the early environment
368 * This reads from the pre-relocation environment
370 * @index: Index of character to read (0 = first)
371 * @return character read, or -ve on error
373 int env_get_char(int index);
376 * env_reloc() - Relocate the 'env' sub-commands
378 * This is used for those unfortunate archs with crappy toolchains
380 void env_reloc(void);
384 * env_import_fdt() - Import environment values from device tree blob
386 * This uses the value of the environment variable "env_fdt_path" as a
387 * path to an fdt node, whose property/value pairs are added to the
390 #ifdef CONFIG_ENV_IMPORT_FDT
391 void env_import_fdt(void);
393 static inline void env_import_fdt(void) {}