+enum env_location {
+ ENVL_UNKNOWN,
+ ENVL_EEPROM,
+ ENVL_EXT4,
+ ENVL_FAT,
+ ENVL_FLASH,
+ ENVL_MMC,
+ ENVL_NAND,
+ ENVL_NVRAM,
+ ENVL_ONENAND,
+ ENVL_REMOTE,
+ ENVL_SPI_FLASH,
+ ENVL_UBI,
+ ENVL_NOWHERE,
+
+ ENVL_COUNT,
+};
+
+/* value for the various operations we want to perform on the env */
+enum env_operation {
+ ENVOP_GET_CHAR, /* we want to call the get_char function */
+ ENVOP_INIT, /* we want to call the init function */
+ ENVOP_LOAD, /* we want to call the load function */
+ ENVOP_SAVE, /* we want to call the save function */
+};
+
+struct env_driver {
+ const char *name;
+ enum env_location location;
+
+ /**
+ * load() - Load the environment from storage
+ *
+ * This method is optional. If not provided, no environment will be
+ * loaded.
+ *
+ * @return 0 if OK, -ve on error
+ */
+ int (*load)(void);
+
+ /**
+ * save() - Save the environment to storage
+ *
+ * This method is required for 'saveenv' to work.
+ *
+ * @return 0 if OK, -ve on error
+ */
+ int (*save)(void);
+
+ /**
+ * init() - Set up the initial pre-relocation environment
+ *
+ * This method is optional.
+ *
+ * @return 0 if OK, -ENOENT if no initial environment could be found,
+ * other -ve on error
+ */
+ int (*init)(void);
+};
+
+/* Declare a new environment location driver */
+#define U_BOOT_ENV_LOCATION(__name) \
+ ll_entry_declare(struct env_driver, __name, env_driver)
+
+/* Declare the name of a location */
+#ifdef CONFIG_CMD_SAVEENV
+#define ENV_NAME(_name) .name = _name,
+#else
+#define ENV_NAME(_name)
+#endif
+
+#ifdef CONFIG_CMD_SAVEENV
+#define env_save_ptr(x) x
+#else
+#define env_save_ptr(x) NULL
+#endif