include/env_internal.h

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * Internal environment header file. This includes direct access to environment
   4  * information such as its size and offset, direct access to the default
   5  * environment and embedded environment (if used). It also provides environment
   6  * drivers with various declarations.
   7  *
   8  * It should not be included by board files, drivers and code other than that
   9  * related to the environment implementation.
  10  *
  11  * (C) Copyright 2002
  12  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  13  */
  14
  15 #ifndef _ENV_INTERNAL_H_
  16 #define _ENV_INTERNAL_H_
  17
  18
  19 /**************************************************************************
  20  *
  21  * The "environment" is stored as a list of '\0' terminated
  22  * "name=value" strings. The end of the list is marked by a double
  23  * '\0'. New entries are always added at the end. Deleting an entry
  24  * shifts the remaining entries to the front. Replacing an entry is a
  25  * combination of deleting the old value and adding the new one.
  26  *
  27  * The environment is preceded by a 32 bit CRC over the data part.
  28  *
  29  *************************************************************************/
  30
  31 #if defined(CONFIG_ENV_IS_IN_FLASH)
  32 # if    defined(CONFIG_ENV_ADDR_REDUND) && \
  33         ((CONFIG_ENV_ADDR >= CONFIG_SYS_MONITOR_BASE) &&                \
  34         (CONFIG_ENV_ADDR_REDUND + CONFIG_ENV_SIZE) <=           \
  35         (CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN))
  36 #  define ENV_IS_EMBEDDED
  37 # endif
  38 # if    (CONFIG_ENV_ADDR >= CONFIG_SYS_MONITOR_BASE) &&         \
  39         (CONFIG_ENV_ADDR + CONFIG_ENV_SIZE) <=                  \
  40         (CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN)
  41 #  define ENV_IS_EMBEDDED
  42 # endif
  43 #endif  /* CONFIG_ENV_IS_IN_FLASH */
  44
  45 #if defined(CONFIG_ENV_IS_IN_NAND)
  46 # if defined(CONFIG_ENV_OFFSET_OOB)
  47 #  ifdef CONFIG_ENV_OFFSET_REDUND
  48 #   error "CONFIG_ENV_OFFSET_REDUND is not supported when CONFIG_ENV_OFFSET_OOB"
  49 #   error "is set"
  50 #  endif
  51 extern unsigned long nand_env_oob_offset;
  52 # endif /* CONFIG_ENV_OFFSET_OOB */
  53 #endif /* CONFIG_ENV_IS_IN_NAND */
  54
  55 #include "compiler.h"
  56
  57 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
  58 # define ENV_HEADER_SIZE        (sizeof(uint32_t) + 1)
  59 #else
  60 # define ENV_HEADER_SIZE        (sizeof(uint32_t))
  61 #endif
  62
  63 #define ENV_SIZE (CONFIG_ENV_SIZE - ENV_HEADER_SIZE)
  64
  65 /*
  66  * If the environment is in RAM, allocate extra space for it in the malloc
  67  * region.
  68  */
  69 #if defined(ENV_IS_EMBEDDED)
  70 #define TOTAL_MALLOC_LEN        CONFIG_SYS_MALLOC_LEN
  71 #elif (CONFIG_ENV_ADDR + CONFIG_ENV_SIZE < CONFIG_SYS_MONITOR_BASE) || \
  72       (CONFIG_ENV_ADDR >= CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN) || \
  73       defined(CONFIG_ENV_IS_IN_NVRAM)
  74 #define TOTAL_MALLOC_LEN        (CONFIG_SYS_MALLOC_LEN + CONFIG_ENV_SIZE)
  75 #else
  76 #define TOTAL_MALLOC_LEN        CONFIG_SYS_MALLOC_LEN
  77 #endif
  78
  79 typedef struct environment_s {
  80         uint32_t        crc;            /* CRC32 over data bytes        */
  81 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
  82         unsigned char   flags;          /* active/obsolete flags ENVF_REDUND_ */
  83 #endif
  84         unsigned char   data[ENV_SIZE]; /* Environment data             */
  85 } env_t;
  86
  87 #ifdef ENV_IS_EMBEDDED
  88 extern env_t embedded_environment;
  89 #endif /* ENV_IS_EMBEDDED */
  90
  91 #ifdef CONFIG_DEFAULT_ENV_IS_RW
  92 extern char default_environment[];
  93 #else
  94 extern const char default_environment[];
  95 #endif
  96
  97 #ifndef DO_DEPS_ONLY
  98
  99 #include <env_attr.h>
 100 #include <env_callback.h>
 101 #include <env_flags.h>
 102 #include <search.h>
 103
 104 enum env_location {
 105         ENVL_UNKNOWN,
 106         ENVL_EEPROM,
 107         ENVL_EXT4,
 108         ENVL_FAT,
 109         ENVL_FLASH,
 110         ENVL_MMC,
 111         ENVL_NAND,
 112         ENVL_NVRAM,
 113         ENVL_ONENAND,
 114         ENVL_REMOTE,
 115         ENVL_SPI_FLASH,
 116         ENVL_UBI,
 117         ENVL_NOWHERE,
 118
 119         ENVL_COUNT,
 120 };
 121
 122 /* value for the various operations we want to perform on the env */
 123 enum env_operation {
 124         ENVOP_GET_CHAR, /* we want to call the get_char function */
 125         ENVOP_INIT,     /* we want to call the init function */
 126         ENVOP_LOAD,     /* we want to call the load function */
 127         ENVOP_SAVE,     /* we want to call the save function */
 128         ENVOP_ERASE,    /* we want to call the erase function */
 129 };
 130
 131 struct env_driver {
 132         const char *name;
 133         enum env_location location;
 134
 135         /**
 136          * load() - Load the environment from storage
 137          *
 138          * This method is required for loading environment
 139          *
 140          * @return 0 if OK, -ve on error
 141          */
 142         int (*load)(void);
 143
 144         /**
 145          * save() - Save the environment to storage
 146          *
 147          * This method is required for 'saveenv' to work.
 148          *
 149          * @return 0 if OK, -ve on error
 150          */
 151         int (*save)(void);
 152
 153         /**
 154          * erase() - Erase the environment on storage
 155          *
 156          * This method is optional and required for 'eraseenv' to work.
 157          *
 158          * @return 0 if OK, -ve on error
 159          */
 160         int (*erase)(void);
 161
 162         /**
 163          * init() - Set up the initial pre-relocation environment
 164          *
 165          * This method is optional.
 166          *
 167          * @return 0 if OK, -ENOENT if no initial environment could be found,
 168          * other -ve on error
 169          */
 170         int (*init)(void);
 171 };
 172
 173 /* Declare a new environment location driver */
 174 #define U_BOOT_ENV_LOCATION(__name)                                     \
 175         ll_entry_declare(struct env_driver, __name, env_driver)
 176
 177 /* Declare the name of a location */
 178 #ifdef CONFIG_CMD_SAVEENV
 179 #define ENV_NAME(_name) .name = _name,
 180 #else
 181 #define ENV_NAME(_name)
 182 #endif
 183
 184 #ifdef CONFIG_CMD_SAVEENV
 185 #define env_save_ptr(x) x
 186 #else
 187 #define env_save_ptr(x) NULL
 188 #endif
 189
 190 #define ENV_SAVE_PTR(x) (CONFIG_IS_ENABLED(SAVEENV) ? (x) : NULL)
 191 #define ENV_ERASE_PTR(x) (IS_ENABLED(CONFIG_CMD_ERASEENV) ? (x) : NULL)
 192
 193 extern struct hsearch_data env_htab;
 194
 195 /**
 196  * env_do_env_set() - Perform the actual setting of an environment variable
 197  *
 198  * Due to the number of places we may need to set an environmental variable
 199  * from we have an exposed internal function that performs the real work and
 200  * then call this from both the command line function as well as other
 201  * locations.
 202  *
 203  * Return: 0 on success or 1 on failure
 204  */
 205 int env_do_env_set(int flag, int argc, char *const argv[], int env_flag);
 206
 207 /**
 208  * env_ext4_get_intf() - Provide the interface for env in EXT4
 209  *
 210  * It is a weak function allowing board to overidde the default interface for
 211  * U-Boot env in EXT4: CONFIG_ENV_EXT4_INTERFACE
 212  *
 213  * Return: string of interface, empty if not supported
 214  */
 215 const char *env_ext4_get_intf(void);
 216
 217 /**
 218  * env_ext4_get_dev_part() - Provide the device and partition for env in EXT4
 219  *
 220  * It is a weak function allowing board to overidde the default device and
 221  * partition used for U-Boot env in EXT4: CONFIG_ENV_EXT4_DEVICE_AND_PART
 222  *
 223  * Return: string of device and partition
 224  */
 225 const char *env_ext4_get_dev_part(void);
 226
 227 /**
 228  * arch_env_get_location()- Provide the best location for the U-Boot environment
 229  *
 230  * It is a weak function allowing board to overidde the environment location
 231  * on architecture level. This has lower priority than env_get_location(),
 232  * which can be defined on board level.
 233  *
 234  * @op: operations performed on the environment
 235  * @prio: priority between the multiple environments, 0 being the
 236  *        highest priority
 237  * Return:  an enum env_location value on success, or -ve error code.
 238  */
 239 enum env_location arch_env_get_location(enum env_operation op, int prio);
 240
 241 /**
 242  * env_get_location()- Provide the best location for the U-Boot environment
 243  *
 244  * It is a weak function allowing board to overidde the environment location
 245  * on board level. This has higher priority than arch_env_get_location(),
 246  * which can be defined on architecture level.
 247  *
 248  * @op: operations performed on the environment
 249  * @prio: priority between the multiple environments, 0 being the
 250  *        highest priority
 251  * Return:  an enum env_location value on success, or -ve error code.
 252  */
 253 enum env_location env_get_location(enum env_operation op, int prio);
 254
 255 /**
 256  * env_fat_get_intf() - Provide the interface for env in FAT
 257  *
 258  * It is a weak function allowing board to overidde the default interface for
 259  * U-Boot env in FAT: CONFIG_ENV_FAT_INTERFACE
 260  *
 261  * Return: string of interface, empty if not supported
 262  */
 263 const char *env_fat_get_intf(void);
 264
 265 /**
 266  * env_fat_get_dev_part() - Provide the device and partition for env in FAT
 267  *
 268  * It is a weak function allowing board to overidde the default device and
 269  * partition used for U-Boot env in FAT: CONFIG_ENV_FAT_DEVICE_AND_PART
 270  *
 271  * Return: string of device and partition
 272  */
 273 char *env_fat_get_dev_part(void);
 274 #endif /* DO_DEPS_ONLY */
 275
 276 #endif /* _ENV_INTERNAL_H_ */