xref: /openbmc/u-boot/include/env_callback.h (revision f68847fa)
1 /*
2  * (C) Copyright 2012
3  * Joe Hershberger, National Instruments, joe.hershberger@ni.com
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 __ENV_CALLBACK_H__
25 #define __ENV_CALLBACK_H__
26 
27 #include <env_flags.h>
28 #include <linker_lists.h>
29 #include <search.h>
30 
31 #define ENV_CALLBACK_VAR ".callbacks"
32 
33 /* Board configs can define additional static callback bindings */
34 #ifndef CONFIG_ENV_CALLBACK_LIST_STATIC
35 #define CONFIG_ENV_CALLBACK_LIST_STATIC
36 #endif
37 
38 #ifdef CONFIG_SILENT_CONSOLE
39 #define SILENT_CALLBACK "silent:silent,"
40 #else
41 #define SILENT_CALLBACK
42 #endif
43 
44 /*
45  * This list of callback bindings is static, but may be overridden by defining
46  * a new association in the ".callbacks" environment variable.
47  */
48 #define ENV_CALLBACK_LIST_STATIC ENV_CALLBACK_VAR ":callbacks," \
49 	ENV_FLAGS_VAR ":flags," \
50 	"baudrate:baudrate," \
51 	"bootfile:bootfile," \
52 	"loadaddr:loadaddr," \
53 	SILENT_CALLBACK \
54 	"stdin:console,stdout:console,stderr:console," \
55 	CONFIG_ENV_CALLBACK_LIST_STATIC
56 
57 struct env_clbk_tbl {
58 	const char *name;		/* Callback name */
59 	int (*callback)(const char *name, const char *value, enum env_op op,
60 		int flags);
61 };
62 
63 struct env_clbk_tbl *find_env_callback(const char *);
64 void env_callback_init(ENTRY *var_entry);
65 
66 /*
67  * Define a callback that can be associated with variables.
68  * when associated through the ".callbacks" environment variable, the callback
69  * will be executed any time the variable is inserted, overwritten, or deleted.
70  */
71 #ifdef CONFIG_SPL_BUILD
72 #define U_BOOT_ENV_CALLBACK(name, callback) \
73 	static inline void _u_boot_env_noop_##name(void) \
74 	{ \
75 		(void)callback; \
76 	}
77 #else
78 #define U_BOOT_ENV_CALLBACK(name, callback) \
79 	ll_entry_declare(struct env_clbk_tbl, name, env_clbk, env_clbk) = \
80 	{#name, callback}
81 #endif
82 
83 #endif /* __ENV_CALLBACK_H__ */
84