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git.ipfire.org Git - u-boot.git/blob - env/nvram.c
2 * (C) Copyright 2000-2010
3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
6 * Andreas Heppel <aheppel@sysgo.de>
8 * SPDX-License-Identifier: GPL-2.0+
12 * 09-18-2001 Andreas Heppel, Sysgo RTS GmbH <aheppel@sysgo.de>
14 * It might not be possible in all cases to use 'memcpy()' to copy
15 * the environment to NVRAM, as the NVRAM might not be mapped into
16 * the memory space. (I.e. this is the case for the BAB750). In those
17 * cases it might be possible to access the NVRAM using a different
18 * method. For example, the RTC on the BAB750 is accessible in IO
19 * space using its address and data registers. To enable usage of
20 * NVRAM in those cases I invented the functions 'nvram_read()' and
21 * 'nvram_write()', which will be activated upon the configuration
22 * #define CONFIG_SYS_NVRAM_ACCESS_ROUTINE. Note, that those functions are
23 * strongly dependent on the used HW, and must be redefined for each
24 * board that wants to use them.
29 #include <environment.h>
30 #include <linux/stddef.h>
34 DECLARE_GLOBAL_DATA_PTR
;
36 #ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE
37 extern void *nvram_read(void *dest
, const long src
, size_t count
);
38 extern void nvram_write(long dest
, const void *src
, size_t count
);
40 env_t
*env_ptr
= (env_t
*)CONFIG_ENV_ADDR
;
43 #ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE
44 /** Call this function from overridden env_get_char_spec() if you need
47 int env_nvram_get_char(int index
)
51 nvram_read(&c
, CONFIG_ENV_ADDR
+ index
, 1);
57 static int env_nvram_load(void)
59 char buf
[CONFIG_ENV_SIZE
];
61 #if defined(CONFIG_SYS_NVRAM_ACCESS_ROUTINE)
62 nvram_read(buf
, CONFIG_ENV_ADDR
, CONFIG_ENV_SIZE
);
64 memcpy(buf
, (void *)CONFIG_ENV_ADDR
, CONFIG_ENV_SIZE
);
66 return env_import(buf
, 1);
69 static int env_nvram_save(void)
74 rcode
= env_export(&env_new
);
78 #ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE
79 nvram_write(CONFIG_ENV_ADDR
, &env_new
, CONFIG_ENV_SIZE
);
81 if (memcpy((char *)CONFIG_ENV_ADDR
, &env_new
, CONFIG_ENV_SIZE
) == NULL
)
88 * Initialize Environment use
90 * We are still running from ROM, so data use is limited
92 static int env_nvram_init(void)
94 #if defined(CONFIG_SYS_NVRAM_ACCESS_ROUTINE)
98 nvram_read(&crc
, CONFIG_ENV_ADDR
, sizeof(ulong
));
99 nvram_read(data
, CONFIG_ENV_ADDR
+ sizeof(ulong
), ENV_SIZE
);
101 if (crc32(0, data
, ENV_SIZE
) == crc
) {
102 gd
->env_addr
= (ulong
)CONFIG_ENV_ADDR
+ sizeof(long);
104 if (crc32(0, env_ptr
->data
, ENV_SIZE
) == env_ptr
->crc
) {
105 gd
->env_addr
= (ulong
)&env_ptr
->data
;
107 gd
->env_valid
= ENV_VALID
;
109 gd
->env_addr
= (ulong
)&default_environment
[0];
110 gd
->env_valid
= ENV_INVALID
;
116 U_BOOT_ENV_LOCATION(nvram
) = {
117 .location
= ENVL_NVRAM
,
119 .load
= env_nvram_load
,
120 .save
= env_save_ptr(env_nvram_save
),
121 .init
= env_nvram_init
,