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
51extern 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
79typedef 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
88extern env_t embedded_environment;
89#endif /* ENV_IS_EMBEDDED */
90
91#ifdef CONFIG_DEFAULT_ENV_IS_RW
92extern char default_environment[];
93#else
94extern 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
104enum 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 */
123enum 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
131struct 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
193extern 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 */
205int 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 */
215const 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 */
225const 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 */
239enum 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 */
253enum 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 */
263const 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 */
273char *env_fat_get_dev_part(void);
274#endif /* DO_DEPS_ONLY */
275
276#endif /* _ENV_INTERNAL_H_ */
277