/* SPDX-License-Identifier: GPL-2.0+ */ /* * Common environment functions and definitions * * (C) Copyright 2000-2009 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. */ #ifndef __ENV_H #define __ENV_H #include <compiler.h> #include <stdbool.h> #include <linux/types.h> struct environment_s; /* Value for environment validity */ enum env_valid { ENV_INVALID, /* No valid environment */ ENV_VALID, /* First or only environment is valid */ ENV_REDUND, /* Redundant environment is valid */ }; /** enum env_op - environment callback operation */ enum env_op { env_op_create, env_op_delete, env_op_overwrite, }; /** struct env_clbk_tbl - declares a new callback */ struct env_clbk_tbl { const char *name; /* Callback name */ int (*callback)(const char *name, const char *value, enum env_op op, int flags); }; /* * Define a callback that can be associated with variables. * when associated through the ".callbacks" environment variable, the callback * will be executed any time the variable is inserted, overwritten, or deleted. * * For SPL these are silently dropped to reduce code size, since environment * callbacks are not supported with SPL. */ #ifdef CONFIG_SPL_BUILD #define U_BOOT_ENV_CALLBACK(name, callback) \ static inline __maybe_unused void _u_boot_env_noop_##name(void) \ { \ (void)callback; \ } #else #define U_BOOT_ENV_CALLBACK(name, callback) \ ll_entry_declare(struct env_clbk_tbl, name, env_clbk) = \ {#name, callback} #endif /** enum env_redund_flags - Flags for the redundand_environment */ enum env_redund_flags { ENV_REDUND_OBSOLETE = 0, ENV_REDUND_ACTIVE = 1, }; /** * env_get_id() - Gets a sequence number for the environment * * This value increments every time the environment changes, so can be used an * an indication of this * * Return: environment ID */ int env_get_id(void); /** * env_init() - Set up the pre-relocation environment * * This locates the environment or uses the default if nothing is available. * This must be called before env_get() will work. * * Return: 0 if OK, -ENODEV if no environment drivers are enabled */ int env_init(void); /** * env_relocate() - Set up the post-relocation environment * * This loads the environment into RAM so that it can be modified. This is * called after relocation, before the environment is used */ void env_relocate(void); /** * env_get() - Look up the value of an environment variable * * In U-Boot proper this can be called before relocation (which is when the * environment is loaded from storage, i.e. GD_FLG_ENV_READY is 0). In that * case this function calls env_get_f(). * * @varname: Variable to look up * Return: value of variable, or NULL if not found */ char *env_get(const char *varname); /* * Like env_get, but prints an error if envvar isn't defined in the * environment. It always returns what env_get does, so it can be used in * place of env_get without changing error handling otherwise. * * @varname: Variable to look up * Return: value of variable, or NULL if not found */ char *from_env(const char *envvar); /** * env_get_f() - Look up the value of an environment variable (early) * * This function is called from env_get() if the environment has not been * loaded yet (GD_FLG_ENV_READY flag is 0). Some environment locations will * support reading the value (slowly) and some will not. * * @varname: Variable to look up * Return: actual length of the variable value excluding the terminating * NULL-byte, or -1 if the variable is not found */ int env_get_f(const char *name, char *buf, unsigned int len); /** * env_get_yesno() - Read an environment variable as a boolean * * Return: 1 if yes/true (Y/y/T/t), -1 if variable does not exist (i.e. default * to true), 0 if otherwise */ int env_get_yesno(const char *var); /** * env_get_autostart() - Check if autostart is enabled * * Return: true if the "autostart" env var exists and is set to "yes" */ bool env_get_autostart(void); /** * env_set() - set an environment variable * * This sets or deletes the value of an environment variable. For setting the * value the variable is created if it does not already exist. * * @varname: Variable to adjust * @value: Value to set for the variable, or NULL or "" to delete the variable * Return: 0 if OK, 1 on error */ int env_set(const char *varname, const char *value); /** * env_get_ulong() - Return an environment variable as an integer value * * Most U-Boot environment variables store hex values. For those which store * (e.g.) base-10 integers, this function can be used to read the value. * * @name: Variable to look up * @base: Base to use (e.g. 10 for base 10, 2 for binary) * @default_val: Default value to return if no value is found * Return: the value found, or @default_val if none */ ulong env_get_ulong(const char *name, int base, ulong default_val); /** * env_set_ulong() - set an environment variable to an integer * * @varname: Variable to adjust * @value: Value to set for the variable (will be converted to a string) * Return: 0 if OK, 1 on error */ int env_set_ulong(const char *varname, ulong value); /** * env_get_hex() - Return an environment variable as a hex value * * Decode an environment as a hex number (it may or may not have a 0x * prefix). If the environment variable cannot be found, or does not start * with hex digits, the default value is returned. * * @varname: Variable to decode * @default_val: Value to return on error */ ulong env_get_hex(const char *varname, ulong default_val); /** * env_set_hex() - set an environment variable to a hex value * * @varname: Variable to adjust * @value: Value to set for the variable (will be converted to a hex string) * Return: 0 if OK, 1 on error */ int env_set_hex(const char *varname, ulong value); /** * env_set_addr - Set an environment variable to an address in hex * * @varname: Environment variable to set * @addr: Value to set it to * Return: 0 if ok, 1 on error */ static inline int env_set_addr(const char *varname, const void *addr) { return env_set_hex(varname, (ulong)addr); } /** * env_complete() - return an auto-complete for environment variables * * @var: partial name to auto-complete * @maxv: Maximum number of matches to return * @cmdv: Returns a list of possible matches * @maxsz: Size of buffer to use for matches * @buf: Buffer to use for matches * @dollar_comp: non-zero to wrap each match in ${...} * Return: number of matches found (in @cmdv) */ int env_complete(char *var, int maxv, char *cmdv[], int maxsz, char *buf, bool dollar_comp); /** * eth_env_get_enetaddr() - Get an ethernet address from the environmnet * * @name: Environment variable to get (e.g. "ethaddr") * @enetaddr: Place to put MAC address (6 bytes) * Return: 0 if OK, 1 on error */ int eth_env_get_enetaddr(const char *name, uint8_t *enetaddr); /** * eth_env_set_enetaddr() - Set an ethernet address in the environmnet * * @name: Environment variable to set (e.g. "ethaddr") * @enetaddr: Pointer to MAC address to put into the variable (6 bytes) * Return: 0 if OK, 1 on error */ int eth_env_set_enetaddr(const char *name, const uint8_t *enetaddr); /** * env_fix_drivers() - Updates envdriver as per relocation */ void env_fix_drivers(void); /** * env_set_default_vars() - reset variables to their default value * * This resets individual variables to their value in the default environment * * @nvars: Number of variables to set/reset * @vars: List of variables to set/reset * @flags: Flags controlling matching (H_... - see search.h) */ int env_set_default_vars(int nvars, char *const vars[], int flags); /** * env_load() - Load the environment from storage * * Return: 0 if OK, -ve on error */ int env_load(void); /** * env_reload() - Re-Load the environment from current storage * * Return: 0 if OK, -ve on error */ int env_reload(void); /** * env_save() - Save the environment to storage * * Return: 0 if OK, -ve on error */ int env_save(void); /** * env_erase() - Erase the environment on storage * * Return: 0 if OK, -ve on error */ int env_erase(void); /** * env_select() - Select the environment storage * * Return: 0 if OK, -ve on error */ int env_select(const char *name); /** * env_import() - Import from a binary representation into hash table * * This imports the environment from a buffer. The format for each variable is * var=value\0 with a double \0 at the end of the buffer. * * @buf: Buffer containing the environment (struct environemnt_s *) * @check: non-zero to check the CRC at the start of the environment, 0 to * ignore it * @flags: Flags controlling matching (H_... - see search.h) * Return: 0 if imported successfully, -ENOMSG if the CRC was bad, -EIO if * something else went wrong */ int env_import(const char *buf, int check, int flags); /** * env_export() - Export the environment to a buffer * * Export from hash table into binary representation * * @env_out: Buffer to contain the environment (must be large enough!) * Return: 0 if OK, 1 on error */ int env_export(struct environment_s *env_out); /** * env_check_redund() - check the two redundant environments * and find out, which is the valid one. * * @buf1: First environment (struct environemnt_s *) * @buf1_read_fail: 0 if buf1 is valid, non-zero if invalid * @buf2: Second environment (struct environemnt_s *) * @buf2_read_fail: 0 if buf2 is valid, non-zero if invalid * Return: 0 if OK, * -EIO if no environment is valid, * -ENOMSG if the CRC was bad */ int env_check_redund(const char *buf1, int buf1_read_fail, const char *buf2, int buf2_read_fail); /** * env_import_redund() - Select and import one of two redundant environments * * @buf1: First environment (struct environemnt_s *) * @buf1_read_fail: 0 if buf1 is valid, non-zero if invalid * @buf2: Second environment (struct environemnt_s *) * @buf2_read_fail: 0 if buf2 is valid, non-zero if invalid * @flags: Flags controlling matching (H_... - see search.h) * Return: 0 if OK, -EIO if no environment is valid, -ENOMSG if the CRC was bad */ int env_import_redund(const char *buf1, int buf1_read_fail, const char *buf2, int buf2_read_fail, int flags); /** * env_get_default() - Look up a variable from the default environment * * @name: Variable to look up * Return: value if found, NULL if not found in default environment */ char *env_get_default(const char *name); /* [re]set to the default environment */ void env_set_default(const char *s, int flags); /** * env_reloc() - Relocate the 'env' sub-commands * * This is used for those unfortunate archs with crappy toolchains */ void env_reloc(void); /** * env_import_fdt() - Import environment values from device tree blob * * This uses the value of the environment variable "env_fdt_path" as a * path to an fdt node, whose property/value pairs are added to the * environment. */ #ifdef CONFIG_ENV_IMPORT_FDT void env_import_fdt(void); #else static inline void env_import_fdt(void) {} #endif #endif