xref: /openbmc/u-boot/include/environment.h (revision 15855700)
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_	1
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	(CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET_REDUND)
49 # endif
50 # if defined(CONFIG_ENV_SECT_SIZE) || defined(CONFIG_ENV_SIZE)
51 #  ifndef  CONFIG_ENV_SECT_SIZE
52 #   define CONFIG_ENV_SECT_SIZE	CONFIG_ENV_SIZE
53 #  endif
54 #  ifndef  CONFIG_ENV_SIZE
55 #   define CONFIG_ENV_SIZE	CONFIG_ENV_SECT_SIZE
56 #  endif
57 # else
58 #  error "Both CONFIG_ENV_SECT_SIZE and CONFIG_ENV_SIZE undefined"
59 # endif
60 # if defined(CONFIG_ENV_ADDR_REDUND) && !defined(CONFIG_ENV_SIZE_REDUND)
61 #  define CONFIG_ENV_SIZE_REDUND	CONFIG_ENV_SIZE
62 # endif
63 # if (CONFIG_ENV_ADDR >= CONFIG_SYS_MONITOR_BASE) && \
64      (CONFIG_ENV_ADDR+CONFIG_ENV_SIZE) <= (CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN)
65 #  define ENV_IS_EMBEDDED	1
66 # endif
67 # if defined(CONFIG_ENV_ADDR_REDUND) || defined(CONFIG_ENV_OFFSET_REDUND)
68 #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT	1
69 # endif
70 # ifdef CONFIG_ENV_IS_EMBEDDED
71 #  error "do not define CONFIG_ENV_IS_EMBEDDED in your board config"
72 #  error "it is calculated automatically for you"
73 # endif
74 #endif	/* CONFIG_ENV_IS_IN_FLASH */
75 
76 #if defined(CONFIG_ENV_IS_IN_NAND)
77 # ifndef CONFIG_ENV_OFFSET
78 #  error "Need to define CONFIG_ENV_OFFSET when using CONFIG_ENV_IS_IN_NAND"
79 # endif
80 # ifndef CONFIG_ENV_SIZE
81 #  error "Need to define CONFIG_ENV_SIZE when using CONFIG_ENV_IS_IN_NAND"
82 # endif
83 # ifdef CONFIG_ENV_OFFSET_REDUND
84 #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT
85 # endif
86 #endif /* CONFIG_ENV_IS_IN_NAND */
87 
88 #if defined(CONFIG_ENV_IS_IN_MG_DISK)
89 # ifndef CONFIG_ENV_ADDR
90 #  error "Need to define CONFIG_ENV_ADDR when using CONFIG_ENV_IS_IN_MG_DISK"
91 # endif
92 # ifndef CONFIG_ENV_SIZE
93 #  error "Need to define CONFIG_ENV_SIZE when using CONFIG_ENV_IS_IN_MG_DISK"
94 # endif
95 #endif /* CONFIG_ENV_IS_IN_MG_DISK */
96 
97 /* Embedded env is only supported for some flash types */
98 #ifdef CONFIG_ENV_IS_EMBEDDED
99 # if !defined(CONFIG_ENV_IS_IN_FLASH) && \
100      !defined(CONFIG_ENV_IS_IN_NAND) && \
101      !defined(CONFIG_ENV_IS_IN_ONENAND)
102 #  error "CONFIG_ENV_IS_EMBEDDED not supported for your flash type"
103 # endif
104 #endif
105 
106 /*
107  * For the flash types where embedded env is supported, but it cannot be
108  * calculated automatically (i.e. NAND), take the board opt-in.
109  */
110 #if defined(CONFIG_ENV_IS_EMBEDDED) && !defined(ENV_IS_EMBEDDED)
111 # define ENV_IS_EMBEDDED 1
112 #endif
113 
114 /* The build system likes to know if the env is embedded */
115 #ifdef DO_DEPS_ONLY
116 # ifdef ENV_IS_EMBEDDED
117 #  define CONFIG_ENV_IS_EMBEDDED
118 # endif
119 #endif
120 
121 #include "compiler.h"
122 
123 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
124 # define ENV_HEADER_SIZE	(sizeof(uint32_t) + 1)
125 #else
126 # define ENV_HEADER_SIZE	(sizeof(uint32_t))
127 #endif
128 
129 
130 #define ENV_SIZE (CONFIG_ENV_SIZE - ENV_HEADER_SIZE)
131 
132 typedef	struct environment_s {
133 	uint32_t	crc;		/* CRC32 over data bytes	*/
134 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
135 	unsigned char	flags;		/* active/obsolete flags	*/
136 #endif
137 	unsigned char	data[ENV_SIZE]; /* Environment data		*/
138 } env_t;
139 
140 /* Function that returns a character from the environment */
141 unsigned char env_get_char (int);
142 
143 /* Function that returns a pointer to a value from the environment */
144 unsigned char *env_get_addr(int);
145 unsigned char env_get_char_memory (int index);
146 
147 /* Function that updates CRC of the enironment */
148 void env_crc_update (void);
149 
150 /* [re]set to the default environment */
151 void set_default_env(void);
152 
153 #endif	/* _ENVIRONMENT_H_ */
154