xref: /openbmc/u-boot/include/environment.h (revision 150c2493)
1 /*
2  * (C) Copyright 2002
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 #ifndef _ENVIRONMENT_H_
25 #define _ENVIRONMENT_H_
26 
27 /**************************************************************************
28  *
29  * The "environment" is stored as a list of '\0' terminated
30  * "name=value" strings. The end of the list is marked by a double
31  * '\0'. New entries are always added at the end. Deleting an entry
32  * shifts the remaining entries to the front. Replacing an entry is a
33  * combination of deleting the old value and adding the new one.
34  *
35  * The environment is preceeded by a 32 bit CRC over the data part.
36  *
37  **************************************************************************
38  */
39 
40 #if defined(CONFIG_ENV_IS_IN_FLASH)
41 # ifndef	CONFIG_ENV_ADDR
42 #  define	CONFIG_ENV_ADDR	(CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET)
43 # endif
44 # ifndef	CONFIG_ENV_OFFSET
45 #  define	CONFIG_ENV_OFFSET (CONFIG_ENV_ADDR - CONFIG_SYS_FLASH_BASE)
46 # endif
47 # if !defined(CONFIG_ENV_ADDR_REDUND) && defined(CONFIG_ENV_OFFSET_REDUND)
48 #  define	CONFIG_ENV_ADDR_REDUND	\
49 		(CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET_REDUND)
50 # endif
51 # if defined(CONFIG_ENV_SECT_SIZE) || defined(CONFIG_ENV_SIZE)
52 #  ifndef	CONFIG_ENV_SECT_SIZE
53 #   define	CONFIG_ENV_SECT_SIZE	CONFIG_ENV_SIZE
54 #  endif
55 #  ifndef	CONFIG_ENV_SIZE
56 #   define	CONFIG_ENV_SIZE	CONFIG_ENV_SECT_SIZE
57 #  endif
58 # else
59 #  error "Both CONFIG_ENV_SECT_SIZE and CONFIG_ENV_SIZE undefined"
60 # endif
61 # if defined(CONFIG_ENV_ADDR_REDUND) && !defined(CONFIG_ENV_SIZE_REDUND)
62 #  define CONFIG_ENV_SIZE_REDUND	CONFIG_ENV_SIZE
63 # endif
64 # if	(CONFIG_ENV_ADDR >= CONFIG_SYS_MONITOR_BASE) &&		\
65 	(CONFIG_ENV_ADDR + CONFIG_ENV_SIZE) <=			\
66 	(CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN)
67 #  define ENV_IS_EMBEDDED
68 # endif
69 # if defined(CONFIG_ENV_ADDR_REDUND) || defined(CONFIG_ENV_OFFSET_REDUND)
70 #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT
71 # endif
72 # ifdef CONFIG_ENV_IS_EMBEDDED
73 #  error "do not define CONFIG_ENV_IS_EMBEDDED in your board config"
74 #  error "it is calculated automatically for you"
75 # endif
76 #endif	/* CONFIG_ENV_IS_IN_FLASH */
77 
78 #if defined(CONFIG_ENV_IS_IN_NAND)
79 # if defined(CONFIG_ENV_OFFSET_OOB)
80 #  ifdef CONFIG_ENV_OFFSET_REDUND
81 #   error "CONFIG_ENV_OFFSET_REDUND is not supported when CONFIG_ENV_OFFSET_OOB"
82 #   error "is set"
83 #  endif
84 extern unsigned long nand_env_oob_offset;
85 #  define CONFIG_ENV_OFFSET nand_env_oob_offset
86 # else
87 #  ifndef CONFIG_ENV_OFFSET
88 #   error "Need to define CONFIG_ENV_OFFSET when using CONFIG_ENV_IS_IN_NAND"
89 #  endif
90 #  ifdef CONFIG_ENV_OFFSET_REDUND
91 #   define CONFIG_SYS_REDUNDAND_ENVIRONMENT
92 #  endif
93 # endif /* CONFIG_ENV_OFFSET_OOB */
94 # ifndef CONFIG_ENV_SIZE
95 #  error "Need to define CONFIG_ENV_SIZE when using CONFIG_ENV_IS_IN_NAND"
96 # endif
97 #endif /* CONFIG_ENV_IS_IN_NAND */
98 
99 /* Embedded env is only supported for some flash types */
100 #ifdef CONFIG_ENV_IS_EMBEDDED
101 # if	!defined(CONFIG_ENV_IS_IN_FLASH)	&& \
102 	!defined(CONFIG_ENV_IS_IN_NAND)		&& \
103 	!defined(CONFIG_ENV_IS_IN_ONENAND)	&& \
104 	!defined(CONFIG_ENV_IS_IN_SPI_FLASH)
105 #  error "CONFIG_ENV_IS_EMBEDDED not supported for your flash type"
106 # endif
107 #endif
108 
109 /*
110  * For the flash types where embedded env is supported, but it cannot be
111  * calculated automatically (i.e. NAND), take the board opt-in.
112  */
113 #if defined(CONFIG_ENV_IS_EMBEDDED) && !defined(ENV_IS_EMBEDDED)
114 # define ENV_IS_EMBEDDED
115 #endif
116 
117 /* The build system likes to know if the env is embedded */
118 #ifdef DO_DEPS_ONLY
119 # ifdef ENV_IS_EMBEDDED
120 #  ifndef CONFIG_ENV_IS_EMBEDDED
121 #   define CONFIG_ENV_IS_EMBEDDED
122 #  endif
123 # endif
124 #endif
125 
126 #include "compiler.h"
127 
128 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
129 # define ENV_HEADER_SIZE	(sizeof(uint32_t) + 1)
130 
131 # define ACTIVE_FLAG   1
132 # define OBSOLETE_FLAG 0
133 #else
134 # define ENV_HEADER_SIZE	(sizeof(uint32_t))
135 #endif
136 
137 #if defined(CONFIG_CMD_SAVEENV) && !defined(CONFIG_ENV_IS_NOWHERE)
138 extern char *env_name_spec;
139 #endif
140 
141 #define ENV_SIZE (CONFIG_ENV_SIZE - ENV_HEADER_SIZE)
142 
143 typedef struct environment_s {
144 	uint32_t	crc;		/* CRC32 over data bytes	*/
145 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
146 	unsigned char	flags;		/* active/obsolete flags	*/
147 #endif
148 	unsigned char	data[ENV_SIZE]; /* Environment data		*/
149 } env_t;
150 
151 #ifdef ENV_IS_EMBEDDED
152 extern env_t environment;
153 #endif /* ENV_IS_EMBEDDED */
154 
155 extern const unsigned char default_environment[];
156 extern env_t *env_ptr;
157 
158 extern void env_relocate_spec(void);
159 extern unsigned char env_get_char_spec(int);
160 
161 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
162 extern void env_reloc(void);
163 #endif
164 
165 #ifndef DO_DEPS_ONLY
166 
167 #include <search.h>
168 
169 extern struct hsearch_data env_htab;
170 
171 /* Function that returns a character from the environment */
172 unsigned char env_get_char(int);
173 
174 /* Function that returns a pointer to a value from the environment */
175 const unsigned char *env_get_addr(int);
176 unsigned char env_get_char_memory(int index);
177 
178 /* Function that updates CRC of the enironment */
179 void env_crc_update(void);
180 
181 /* [re]set to the default environment */
182 void set_default_env(const char *s);
183 
184 /* [re]set individual variables to their value in the default environment */
185 int set_default_vars(int nvars, char * const vars[]);
186 
187 /* Import from binary representation into hash table */
188 int env_import(const char *buf, int check);
189 
190 /*
191  * Check if variable "name" can be changed from oldval to newval,
192  * and if so, apply the changes (e.g. baudrate).
193  * When (flag & H_FORCE) is set, it does not print out any error
194  * message and forces overwriting of write-once variables.
195  */
196 int env_check_apply(const char *name, const char *oldval,
197 			const char *newval, int flag);
198 
199 #endif /* DO_DEPS_ONLY */
200 
201 #endif /* _ENVIRONMENT_H_ */
202