/*
   * (C) Copyright 2002
   * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   *

   * SPDX-License-Identifier:	GPL-2.0+

   */
  
  #ifndef _ENVIRONMENT_H_

  #define _ENVIRONMENT_H_

  #include <linux/kconfig.h>

  /**************************************************************************
   *
   * The "environment" is stored as a list of '\0' terminated
   * "name=value" strings. The end of the list is marked by a double
   * '\0'. New entries are always added at the end. Deleting an entry
   * shifts the remaining entries to the front. Replacing an entry is a
   * combination of deleting the old value and adding the new one.
   *

   * The environment is preceded by a 32 bit CRC over the data part.

   *

   *************************************************************************/

  #if defined(CONFIG_ENV_IS_IN_FLASH)

  # ifndef	CONFIG_ENV_ADDR
  #  define	CONFIG_ENV_ADDR	(CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET)

  # endif

  # ifndef	CONFIG_ENV_OFFSET
  #  define	CONFIG_ENV_OFFSET (CONFIG_ENV_ADDR - CONFIG_SYS_FLASH_BASE)

  # endif

  # if !defined(CONFIG_ENV_ADDR_REDUND) && defined(CONFIG_ENV_OFFSET_REDUND)

  #  define	CONFIG_ENV_ADDR_REDUND	\
  		(CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET_REDUND)

  # endif

  # if defined(CONFIG_ENV_SECT_SIZE) || defined(CONFIG_ENV_SIZE)

  #  ifndef	CONFIG_ENV_SECT_SIZE
  #   define	CONFIG_ENV_SECT_SIZE	CONFIG_ENV_SIZE

  #  endif

  #  ifndef	CONFIG_ENV_SIZE
  #   define	CONFIG_ENV_SIZE	CONFIG_ENV_SECT_SIZE

  #  endif
  # else

  #  error "Both CONFIG_ENV_SECT_SIZE and CONFIG_ENV_SIZE undefined"

  # endif

  # if defined(CONFIG_ENV_ADDR_REDUND) && !defined(CONFIG_ENV_SIZE_REDUND)
  #  define CONFIG_ENV_SIZE_REDUND	CONFIG_ENV_SIZE

  # endif

  # if	(CONFIG_ENV_ADDR >= CONFIG_SYS_MONITOR_BASE) &&		\
  	(CONFIG_ENV_ADDR + CONFIG_ENV_SIZE) <=			\
  	(CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN)

  #  define ENV_IS_EMBEDDED

  # endif

  # if defined(CONFIG_ENV_ADDR_REDUND) || defined(CONFIG_ENV_OFFSET_REDUND)

  #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT

  # endif

  # ifdef CONFIG_ENV_IS_EMBEDDED
  #  error "do not define CONFIG_ENV_IS_EMBEDDED in your board config"
  #  error "it is calculated automatically for you"
  # endif

  #endif	/* CONFIG_ENV_IS_IN_FLASH */

  #if defined(CONFIG_ENV_IS_IN_MMC)
  # ifdef CONFIG_ENV_OFFSET_REDUND
  #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT
  # endif
  #endif

  #if defined(CONFIG_ENV_IS_IN_NAND)

  # if defined(CONFIG_ENV_OFFSET_OOB)
  #  ifdef CONFIG_ENV_OFFSET_REDUND
  #   error "CONFIG_ENV_OFFSET_REDUND is not supported when CONFIG_ENV_OFFSET_OOB"
  #   error "is set"
  #  endif
  extern unsigned long nand_env_oob_offset;
  #  define CONFIG_ENV_OFFSET nand_env_oob_offset
  # else
  #  ifndef CONFIG_ENV_OFFSET
  #   error "Need to define CONFIG_ENV_OFFSET when using CONFIG_ENV_IS_IN_NAND"
  #  endif
  #  ifdef CONFIG_ENV_OFFSET_REDUND
  #   define CONFIG_SYS_REDUNDAND_ENVIRONMENT
  #  endif
  # endif /* CONFIG_ENV_OFFSET_OOB */

  # ifndef CONFIG_ENV_SIZE
  #  error "Need to define CONFIG_ENV_SIZE when using CONFIG_ENV_IS_IN_NAND"

  # endif

  #endif /* CONFIG_ENV_IS_IN_NAND */

  #if defined(CONFIG_ENV_IS_IN_UBI)
  # ifndef CONFIG_ENV_UBI_PART
  #  error "Need to define CONFIG_ENV_UBI_PART when using CONFIG_ENV_IS_IN_UBI"
  # endif
  # ifndef CONFIG_ENV_UBI_VOLUME
  #  error "Need to define CONFIG_ENV_UBI_VOLUME when using CONFIG_ENV_IS_IN_UBI"
  # endif

  # if defined(CONFIG_ENV_UBI_VOLUME_REDUND)
  #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT
  # endif

  # ifndef CONFIG_ENV_SIZE
  #  error "Need to define CONFIG_ENV_SIZE when using CONFIG_ENV_IS_IN_UBI"
  # endif
  # ifndef CONFIG_CMD_UBI
  #  error "Need to define CONFIG_CMD_UBI when using CONFIG_ENV_IS_IN_UBI"
  # endif
  #endif /* CONFIG_ENV_IS_IN_UBI */

  /* Embedded env is only supported for some flash types */
  #ifdef CONFIG_ENV_IS_EMBEDDED

  # if	!defined(CONFIG_ENV_IS_IN_FLASH)	&& \
  	!defined(CONFIG_ENV_IS_IN_NAND)		&& \
  	!defined(CONFIG_ENV_IS_IN_ONENAND)	&& \
  	!defined(CONFIG_ENV_IS_IN_SPI_FLASH)

  #  error "CONFIG_ENV_IS_EMBEDDED not supported for your flash type"
  # endif
  #endif
  
  /*
   * For the flash types where embedded env is supported, but it cannot be
   * calculated automatically (i.e. NAND), take the board opt-in.
   */
  #if defined(CONFIG_ENV_IS_EMBEDDED) && !defined(ENV_IS_EMBEDDED)

  # define ENV_IS_EMBEDDED

  #endif
  
  /* The build system likes to know if the env is embedded */
  #ifdef DO_DEPS_ONLY
  # ifdef ENV_IS_EMBEDDED

  #  ifndef CONFIG_ENV_IS_EMBEDDED
  #   define CONFIG_ENV_IS_EMBEDDED
  #  endif

  # endif
  #endif

  #include "compiler.h"

  #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT

  # define ENV_HEADER_SIZE	(sizeof(uint32_t) + 1)

  
  # define ACTIVE_FLAG   1
  # define OBSOLETE_FLAG 0

  #else

  # define ENV_HEADER_SIZE	(sizeof(uint32_t))

  #endif

  #define ENV_SIZE (CONFIG_ENV_SIZE - ENV_HEADER_SIZE)

  typedef struct environment_s {

  	uint32_t	crc;		/* CRC32 over data bytes	*/

  #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT

  	unsigned char	flags;		/* active/obsolete flags	*/
  #endif
  	unsigned char	data[ENV_SIZE]; /* Environment data		*/

  } env_t;

  #ifdef ENV_IS_EMBEDDED
  extern env_t environment;
  #endif /* ENV_IS_EMBEDDED */

  extern const unsigned char default_environment[];

  extern env_t *env_ptr;

  #if defined(CONFIG_NEEDS_MANUAL_RELOC)
  extern void env_reloc(void);
  #endif

  #ifdef CONFIG_ENV_IS_IN_MMC
  #include <mmc.h>
  
  extern int mmc_get_env_addr(struct mmc *mmc, int copy, u32 *env_addr);

  # ifdef CONFIG_SYS_MMC_ENV_PART
  extern uint mmc_get_env_part(struct mmc *mmc);
  # endif

  #endif

  #ifndef DO_DEPS_ONLY

  #include <env_attr.h>
  #include <env_callback.h>

  #include <env_flags.h>

  #include <search.h>

  /* 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_location {

  	ENVL_UNKNOWN,

  	ENVL_EEPROM,

  	ENVL_ESATA,

  	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

  extern struct hsearch_data env_htab;

  /* Function that updates CRC of the enironment */

  void env_crc_update(void);

  /* Look up the variable from the default environment */

  char *env_get_default(const char *name);

  /* [re]set to the default environment */

  void set_default_env(const char *s);

  /* [re]set individual variables to their value in the default environment */
  int set_default_vars(int nvars, char * const vars[]);

  /* Import from binary representation into hash table */
  int env_import(const char *buf, int check);

  /* Export from hash table into binary representation */
  int env_export(env_t *env_out);

  #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
  /* Select and import one of two redundant environments */

  int env_import_redund(const char *buf1, int buf1_status,
  		      const char *buf2, int buf2_status);

  #endif

  /**

   * env_get_char() - Get a character from the early environment
   *
   * This reads from the pre-relocation environemnt
   *
   * @index: Index of character to read (0 = first)
   * @return character read, or -ve on error
   */
  int env_get_char(int index);

  /**
   * env_load() - Load the environment from storage
   *
   * @return 0 if OK, -ve on error
   */
  int env_load(void);

  /**
   * env_save() - Save the environment to storage
   *
   * @return 0 if OK, -ve on error
   */
  int env_save(void);

  #endif /* DO_DEPS_ONLY */

  #endif /* _ENVIRONMENT_H_ */