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1 | This file contains some assistance for using "make *config". | ||
2 | |||
3 | Use "make help" to list all of the possible configuration targets. | ||
4 | |||
5 | The xconfig ('qconf') and menuconfig ('mconf') programs also | ||
6 | have embedded help text. Be sure to check it for navigation, | ||
7 | search, and other general help text. | ||
8 | |||
9 | ====================================================================== | ||
10 | General | ||
11 | -------------------------------------------------- | ||
12 | |||
13 | New kernel releases often introduce new config symbols. Often more | ||
14 | important, new kernel releases may rename config symbols. When | ||
15 | this happens, using a previously working .config file and running | ||
16 | "make oldconfig" won't necessarily produce a working new kernel | ||
17 | for you, so you may find that you need to see what NEW kernel | ||
18 | symbols have been introduced. | ||
19 | |||
20 | To see a list of new config symbols when using "make oldconfig", use | ||
21 | |||
22 | cp user/some/old.config .config | ||
23 | yes "" | make oldconfig >conf.new | ||
24 | |||
25 | and the config program will list as (NEW) any new symbols that have | ||
26 | unknown values. Of course, the .config file is also updated with | ||
27 | new (default) values, so you can use: | ||
28 | |||
29 | grep "(NEW)" conf.new | ||
30 | |||
31 | to see the new config symbols or you can 'diff' the previous and | ||
32 | new .config files to see the differences: | ||
33 | |||
34 | diff .config.old .config | less | ||
35 | |||
36 | (Yes, we need something better here.) | ||
37 | |||
38 | |||
39 | ====================================================================== | ||
40 | menuconfig | ||
41 | -------------------------------------------------- | ||
42 | |||
43 | SEARCHING for CONFIG symbols | ||
44 | |||
45 | Searching in menuconfig: | ||
46 | |||
47 | The Search function searches for kernel configuration symbol | ||
48 | names, so you have to know something close to what you are | ||
49 | looking for. | ||
50 | |||
51 | Example: | ||
52 | /hotplug | ||
53 | This lists all config symbols that contain "hotplug", | ||
54 | e.g., HOTPLUG, HOTPLUG_CPU, MEMORY_HOTPLUG. | ||
55 | |||
56 | For search help, enter / followed TAB-TAB-TAB (to highlight | ||
57 | <Help>) and Enter. This will tell you that you can also use | ||
58 | regular expressions (regexes) in the search string, so if you | ||
59 | are not interested in MEMORY_HOTPLUG, you could try | ||
60 | |||
61 | /^hotplug | ||
62 | |||
63 | |||
64 | ______________________________________________________________________ | ||
65 | Color Themes for 'menuconfig' | ||
66 | |||
67 | It is possible to select different color themes using the variable | ||
68 | MENUCONFIG_COLOR. To select a theme use: | ||
69 | |||
70 | make MENUCONFIG_COLOR=<theme> menuconfig | ||
71 | |||
72 | Available themes are: | ||
73 | mono => selects colors suitable for monochrome displays | ||
74 | blackbg => selects a color scheme with black background | ||
75 | classic => theme with blue background. The classic look | ||
76 | bluetitle => a LCD friendly version of classic. (default) | ||
77 | |||
78 | ______________________________________________________________________ | ||
79 | Environment variables in 'menuconfig' | ||
80 | |||
81 | KCONFIG_ALLCONFIG | ||
82 | -------------------------------------------------- | ||
83 | (partially based on lkml email from/by Rob Landley, re: miniconfig) | ||
84 | -------------------------------------------------- | ||
85 | The allyesconfig/allmodconfig/allnoconfig/randconfig variants can | ||
86 | also use the environment variable KCONFIG_ALLCONFIG as a flag or a | ||
87 | filename that contains config symbols that the user requires to be | ||
88 | set to a specific value. If KCONFIG_ALLCONFIG is used without a | ||
89 | filename, "make *config" checks for a file named | ||
90 | "all{yes/mod/no/random}.config" (corresponding to the *config command | ||
91 | that was used) for symbol values that are to be forced. If this file | ||
92 | is not found, it checks for a file named "all.config" to contain forced | ||
93 | values. | ||
94 | |||
95 | This enables you to create "miniature" config (miniconfig) or custom | ||
96 | config files containing just the config symbols that you are interested | ||
97 | in. Then the kernel config system generates the full .config file, | ||
98 | including dependencies of your miniconfig file, based on the miniconfig | ||
99 | file. | ||
100 | |||
101 | This 'KCONFIG_ALLCONFIG' file is a config file which contains | ||
102 | (usually a subset of all) preset config symbols. These variable | ||
103 | settings are still subject to normal dependency checks. | ||
104 | |||
105 | Examples: | ||
106 | KCONFIG_ALLCONFIG=custom-notebook.config make allnoconfig | ||
107 | or | ||
108 | KCONFIG_ALLCONFIG=mini.config make allnoconfig | ||
109 | or | ||
110 | make KCONFIG_ALLCONFIG=mini.config allnoconfig | ||
111 | |||
112 | These examples will disable most options (allnoconfig) but enable or | ||
113 | disable the options that are explicitly listed in the specified | ||
114 | mini-config files. | ||
115 | |||
116 | KCONFIG_NOSILENTUPDATE | ||
117 | -------------------------------------------------- | ||
118 | If this variable has a non-blank value, it prevents silent kernel | ||
119 | config udpates (requires explicit updates). | ||
120 | |||
121 | KCONFIG_CONFIG | ||
122 | -------------------------------------------------- | ||
123 | This environment variable can be used to specify a default kernel config | ||
124 | file name to override the default name of ".config". | ||
125 | |||
126 | KCONFIG_OVERWRITECONFIG | ||
127 | -------------------------------------------------- | ||
128 | If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not | ||
129 | break symlinks when .config is a symlink to somewhere else. | ||
130 | |||
131 | KCONFIG_NOTIMESTAMP | ||
132 | -------------------------------------------------- | ||
133 | If this environment variable exists and is non-null, the timestamp line | ||
134 | in generated .config files is omitted. | ||
135 | |||
136 | KCONFIG_AUTOCONFIG | ||
137 | -------------------------------------------------- | ||
138 | This environment variable can be set to specify the path & name of the | ||
139 | "auto.conf" file. Its default value is "include/config/auto.conf". | ||
140 | |||
141 | KCONFIG_AUTOHEADER | ||
142 | -------------------------------------------------- | ||
143 | This environment variable can be set to specify the path & name of the | ||
144 | "autoconf.h" (header) file. Its default value is "include/linux/autoconf.h". | ||
145 | |||
146 | ______________________________________________________________________ | ||
147 | menuconfig User Interface Options | ||
148 | ---------------------------------------------------------------------- | ||
149 | MENUCONFIG_MODE | ||
150 | -------------------------------------------------- | ||
151 | This mode shows all sub-menus in one large tree. | ||
152 | |||
153 | Example: | ||
154 | MENUCONFIG_MODE=single_menu make menuconfig | ||
155 | |||
156 | ====================================================================== | ||
157 | xconfig | ||
158 | -------------------------------------------------- | ||
159 | |||
160 | Searching in xconfig: | ||
161 | |||
162 | The Search function searches for kernel configuration symbol | ||
163 | names, so you have to know something close to what you are | ||
164 | looking for. | ||
165 | |||
166 | Example: | ||
167 | Ctrl-F hotplug | ||
168 | or | ||
169 | Menu: File, Search, hotplug | ||
170 | |||
171 | lists all config symbol entries that contain "hotplug" in | ||
172 | the symbol name. In this Search dialog, you may change the | ||
173 | config setting for any of the entries that are not grayed out. | ||
174 | You can also enter a different search string without having | ||
175 | to return to the main menu. | ||
176 | |||
177 | |||
178 | ====================================================================== | ||
179 | gconfig | ||
180 | -------------------------------------------------- | ||
181 | |||
182 | Searching in gconfig: | ||
183 | |||
184 | None (gconfig isn't maintained as well as xconfig or menuconfig); | ||
185 | however, gconfig does have a few more viewing choices than | ||
186 | xconfig does. | ||
187 | |||
188 | ### | ||