0001 ===================
0002 Kconfig make config
0003 ===================
0004
0005 This file contains some assistance for using `make *config`.
0006
0007 Use "make help" to list all of the possible configuration targets.
0008
0009 The xconfig ('qconf'), menuconfig ('mconf'), and nconfig ('nconf')
0010 programs also have embedded help text. Be sure to check that for
0011 navigation, search, and other general help text.
0012
0013 General
0014 -------
0015
0016 New kernel releases often introduce new config symbols. Often more
0017 important, new kernel releases may rename config symbols. When
0018 this happens, using a previously working .config file and running
0019 "make oldconfig" won't necessarily produce a working new kernel
0020 for you, so you may find that you need to see what NEW kernel
0021 symbols have been introduced.
0022
0023 To see a list of new config symbols, use::
0024
0025 cp user/some/old.config .config
0026 make listnewconfig
0027
0028 and the config program will list any new symbols, one per line.
0029
0030 Alternatively, you can use the brute force method::
0031
0032 make oldconfig
0033 scripts/diffconfig .config.old .config | less
0034
0035 ----------------------------------------------------------------------
0036
0037 Environment variables for `*config`
0038
0039 KCONFIG_CONFIG
0040 --------------
0041 This environment variable can be used to specify a default kernel config
0042 file name to override the default name of ".config".
0043
0044 KCONFIG_DEFCONFIG_LIST
0045 ----------------------
0046
0047 This environment variable specifies a list of config files which can be used
0048 as a base configuration in case the .config does not exist yet. Entries in
0049 the list are separated with whitespaces to each other, and the first one
0050 that exists is used.
0051
0052 KCONFIG_OVERWRITECONFIG
0053 -----------------------
0054 If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not
0055 break symlinks when .config is a symlink to somewhere else.
0056
0057 `CONFIG_`
0058 ---------
0059 If you set `CONFIG_` in the environment, Kconfig will prefix all symbols
0060 with its value when saving the configuration, instead of using the default,
0061 `CONFIG_`.
0062
0063 ----------------------------------------------------------------------
0064
0065 Environment variables for '{allyes/allmod/allno/rand}config'
0066
0067 KCONFIG_ALLCONFIG
0068 -----------------
0069 (partially based on lkml email from/by Rob Landley, re: miniconfig)
0070
0071 --------------------------------------------------
0072
0073 The allyesconfig/allmodconfig/allnoconfig/randconfig variants can also
0074 use the environment variable KCONFIG_ALLCONFIG as a flag or a filename
0075 that contains config symbols that the user requires to be set to a
0076 specific value. If KCONFIG_ALLCONFIG is used without a filename where
0077 KCONFIG_ALLCONFIG == "" or KCONFIG_ALLCONFIG == "1", `make *config`
0078 checks for a file named "all{yes/mod/no/def/random}.config"
0079 (corresponding to the `*config` command that was used) for symbol values
0080 that are to be forced. If this file is not found, it checks for a
0081 file named "all.config" to contain forced values.
0082
0083 This enables you to create "miniature" config (miniconfig) or custom
0084 config files containing just the config symbols that you are interested
0085 in. Then the kernel config system generates the full .config file,
0086 including symbols of your miniconfig file.
0087
0088 This 'KCONFIG_ALLCONFIG' file is a config file which contains
0089 (usually a subset of all) preset config symbols. These variable
0090 settings are still subject to normal dependency checks.
0091
0092 Examples::
0093
0094 KCONFIG_ALLCONFIG=custom-notebook.config make allnoconfig
0095
0096 or::
0097
0098 KCONFIG_ALLCONFIG=mini.config make allnoconfig
0099
0100 or::
0101
0102 make KCONFIG_ALLCONFIG=mini.config allnoconfig
0103
0104 These examples will disable most options (allnoconfig) but enable or
0105 disable the options that are explicitly listed in the specified
0106 mini-config files.
0107
0108 ----------------------------------------------------------------------
0109
0110 Environment variables for 'randconfig'
0111
0112 KCONFIG_SEED
0113 ------------
0114 You can set this to the integer value used to seed the RNG, if you want
0115 to somehow debug the behaviour of the kconfig parser/frontends.
0116 If not set, the current time will be used.
0117
0118 KCONFIG_PROBABILITY
0119 -------------------
0120 This variable can be used to skew the probabilities. This variable can
0121 be unset or empty, or set to three different formats:
0122
0123 ======================= ================== =====================
0124 KCONFIG_PROBABILITY y:n split y:m:n split
0125 ======================= ================== =====================
0126 unset or empty 50 : 50 33 : 33 : 34
0127 N N : 100-N N/2 : N/2 : 100-N
0128 [1] N:M N+M : 100-(N+M) N : M : 100-(N+M)
0129 [2] N:M:L N : 100-N M : L : 100-(M+L)
0130 ======================= ================== =====================
0131
0132 where N, M and L are integers (in base 10) in the range [0,100], and so
0133 that:
0134
0135 [1] N+M is in the range [0,100]
0136
0137 [2] M+L is in the range [0,100]
0138
0139 Examples::
0140
0141 KCONFIG_PROBABILITY=10
0142 10% of booleans will be set to 'y', 90% to 'n'
0143 5% of tristates will be set to 'y', 5% to 'm', 90% to 'n'
0144 KCONFIG_PROBABILITY=15:25
0145 40% of booleans will be set to 'y', 60% to 'n'
0146 15% of tristates will be set to 'y', 25% to 'm', 60% to 'n'
0147 KCONFIG_PROBABILITY=10:15:15
0148 10% of booleans will be set to 'y', 90% to 'n'
0149 15% of tristates will be set to 'y', 15% to 'm', 70% to 'n'
0150
0151 ----------------------------------------------------------------------
0152
0153 Environment variables for 'syncconfig'
0154
0155 KCONFIG_NOSILENTUPDATE
0156 ----------------------
0157 If this variable has a non-blank value, it prevents silent kernel
0158 config updates (requires explicit updates).
0159
0160 KCONFIG_AUTOCONFIG
0161 ------------------
0162 This environment variable can be set to specify the path & name of the
0163 "auto.conf" file. Its default value is "include/config/auto.conf".
0164
0165 KCONFIG_AUTOHEADER
0166 ------------------
0167 This environment variable can be set to specify the path & name of the
0168 "autoconf.h" (header) file.
0169 Its default value is "include/generated/autoconf.h".
0170
0171
0172 ----------------------------------------------------------------------
0173
0174 menuconfig
0175 ----------
0176
0177 SEARCHING for CONFIG symbols
0178
0179 Searching in menuconfig:
0180
0181 The Search function searches for kernel configuration symbol
0182 names, so you have to know something close to what you are
0183 looking for.
0184
0185 Example::
0186
0187 /hotplug
0188 This lists all config symbols that contain "hotplug",
0189 e.g., HOTPLUG_CPU, MEMORY_HOTPLUG.
0190
0191 For search help, enter / followed by TAB-TAB (to highlight
0192 <Help>) and Enter. This will tell you that you can also use
0193 regular expressions (regexes) in the search string, so if you
0194 are not interested in MEMORY_HOTPLUG, you could try::
0195
0196 /^hotplug
0197
0198 When searching, symbols are sorted thus:
0199
0200 - first, exact matches, sorted alphabetically (an exact match
0201 is when the search matches the complete symbol name);
0202 - then, other matches, sorted alphabetically.
0203
0204 For example: ^ATH.K matches:
0205
0206 ATH5K ATH9K ATH5K_AHB ATH5K_DEBUG [...] ATH6KL ATH6KL_DEBUG
0207 [...] ATH9K_AHB ATH9K_BTCOEX_SUPPORT ATH9K_COMMON [...]
0208
0209 of which only ATH5K and ATH9K match exactly and so are sorted
0210 first (and in alphabetical order), then come all other symbols,
0211 sorted in alphabetical order.
0212
0213 ----------------------------------------------------------------------
0214
0215 User interface options for 'menuconfig'
0216
0217 MENUCONFIG_COLOR
0218 ----------------
0219 It is possible to select different color themes using the variable
0220 MENUCONFIG_COLOR. To select a theme use::
0221
0222 make MENUCONFIG_COLOR=<theme> menuconfig
0223
0224 Available themes are::
0225
0226 - mono => selects colors suitable for monochrome displays
0227 - blackbg => selects a color scheme with black background
0228 - classic => theme with blue background. The classic look
0229 - bluetitle => a LCD friendly version of classic. (default)
0230
0231 MENUCONFIG_MODE
0232 ---------------
0233 This mode shows all sub-menus in one large tree.
0234
0235 Example::
0236
0237 make MENUCONFIG_MODE=single_menu menuconfig
0238
0239 ----------------------------------------------------------------------
0240
0241 nconfig
0242 -------
0243
0244 nconfig is an alternate text-based configurator. It lists function
0245 keys across the bottom of the terminal (window) that execute commands.
0246 You can also just use the corresponding numeric key to execute the
0247 commands unless you are in a data entry window. E.g., instead of F6
0248 for Save, you can just press 6.
0249
0250 Use F1 for Global help or F3 for the Short help menu.
0251
0252 Searching in nconfig:
0253
0254 You can search either in the menu entry "prompt" strings
0255 or in the configuration symbols.
0256
0257 Use / to begin a search through the menu entries. This does
0258 not support regular expressions. Use <Down> or <Up> for
0259 Next hit and Previous hit, respectively. Use <Esc> to
0260 terminate the search mode.
0261
0262 F8 (SymSearch) searches the configuration symbols for the
0263 given string or regular expression (regex).
0264
0265 NCONFIG_MODE
0266 ------------
0267 This mode shows all sub-menus in one large tree.
0268
0269 Example::
0270
0271 make NCONFIG_MODE=single_menu nconfig
0272
0273 ----------------------------------------------------------------------
0274
0275 xconfig
0276 -------
0277
0278 Searching in xconfig:
0279
0280 The Search function searches for kernel configuration symbol
0281 names, so you have to know something close to what you are
0282 looking for.
0283
0284 Example::
0285
0286 Ctrl-F hotplug
0287
0288 or::
0289
0290 Menu: File, Search, hotplug
0291
0292 lists all config symbol entries that contain "hotplug" in
0293 the symbol name. In this Search dialog, you may change the
0294 config setting for any of the entries that are not grayed out.
0295 You can also enter a different search string without having
0296 to return to the main menu.
0297
0298
0299 ----------------------------------------------------------------------
0300
0301 gconfig
0302 -------
0303
0304 Searching in gconfig:
0305
0306 There is no search command in gconfig. However, gconfig does
0307 have several different viewing choices, modes, and options.
