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Diffstat (limited to 'Documentation/kbuild/kconfig.txt')
| -rw-r--r-- | Documentation/kbuild/kconfig.txt | 201 |
1 files changed, 125 insertions, 76 deletions
diff --git a/Documentation/kbuild/kconfig.txt b/Documentation/kbuild/kconfig.txt index 26a7c0a9319..bbc99c0c109 100644 --- a/Documentation/kbuild/kconfig.txt +++ b/Documentation/kbuild/kconfig.txt @@ -20,83 +20,52 @@ symbols have been introduced. To see a list of new config symbols when using "make oldconfig", use cp user/some/old.config .config - yes "" | make oldconfig >conf.new + make listnewconfig -and the config program will list as (NEW) any new symbols that have -unknown values. Of course, the .config file is also updated with -new (default) values, so you can use: - - grep "(NEW)" conf.new - -to see the new config symbols or you can 'diff' the previous and -new .config files to see the differences: - - diff .config.old .config | less - -(Yes, we need something better here.) - - -====================================================================== -menuconfig --------------------------------------------------- - -SEARCHING for CONFIG symbols - -Searching in menuconfig: - - The Search function searches for kernel configuration symbol - names, so you have to know something close to what you are - looking for. - - Example: - /hotplug - This lists all config symbols that contain "hotplug", - e.g., HOTPLUG, HOTPLUG_CPU, MEMORY_HOTPLUG. - - For search help, enter / followed TAB-TAB-TAB (to highlight - <Help>) and Enter. This will tell you that you can also use - regular expressions (regexes) in the search string, so if you - are not interested in MEMORY_HOTPLUG, you could try - - /^hotplug +and the config program will list any new symbols, one per line. + scripts/diffconfig .config.old .config | less ______________________________________________________________________ -Color Themes for 'menuconfig' +Environment variables for '*config' -It is possible to select different color themes using the variable -MENUCONFIG_COLOR. To select a theme use: +KCONFIG_CONFIG +-------------------------------------------------- +This environment variable can be used to specify a default kernel config +file name to override the default name of ".config". - make MENUCONFIG_COLOR=<theme> menuconfig +KCONFIG_OVERWRITECONFIG +-------------------------------------------------- +If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not +break symlinks when .config is a symlink to somewhere else. -Available themes are: - mono => selects colors suitable for monochrome displays - blackbg => selects a color scheme with black background - classic => theme with blue background. The classic look - bluetitle => a LCD friendly version of classic. (default) +CONFIG_ +-------------------------------------------------- +If you set CONFIG_ in the environment, Kconfig will prefix all symbols +with its value when saving the configuration, instead of using the default, +"CONFIG_". ______________________________________________________________________ -Environment variables in 'menuconfig' +Environment variables for '{allyes/allmod/allno/rand}config' KCONFIG_ALLCONFIG -------------------------------------------------- (partially based on lkml email from/by Rob Landley, re: miniconfig) -------------------------------------------------- -The allyesconfig/allmodconfig/allnoconfig/randconfig variants can -also use the environment variable KCONFIG_ALLCONFIG as a flag or a -filename that contains config symbols that the user requires to be -set to a specific value. If KCONFIG_ALLCONFIG is used without a -filename, "make *config" checks for a file named -"all{yes/mod/no/random}.config" (corresponding to the *config command -that was used) for symbol values that are to be forced. If this file -is not found, it checks for a file named "all.config" to contain forced -values. +The allyesconfig/allmodconfig/allnoconfig/randconfig variants can also +use the environment variable KCONFIG_ALLCONFIG as a flag or a filename +that contains config symbols that the user requires to be set to a +specific value. If KCONFIG_ALLCONFIG is used without a filename where +KCONFIG_ALLCONFIG == "" or KCONFIG_ALLCONFIG == "1", "make *config" +checks for a file named "all{yes/mod/no/def/random}.config" +(corresponding to the *config command that was used) for symbol values +that are to be forced. If this file is not found, it checks for a +file named "all.config" to contain forced values. This enables you to create "miniature" config (miniconfig) or custom config files containing just the config symbols that you are interested in. Then the kernel config system generates the full .config file, -including dependencies of your miniconfig file, based on the miniconfig -file. +including symbols of your miniconfig file. This 'KCONFIG_ALLCONFIG' file is a config file which contains (usually a subset of all) preset config symbols. These variable @@ -113,45 +82,125 @@ These examples will disable most options (allnoconfig) but enable or disable the options that are explicitly listed in the specified mini-config files. -KCONFIG_NOSILENTUPDATE --------------------------------------------------- -If this variable has a non-blank value, it prevents silent kernel -config udpates (requires explicit updates). +______________________________________________________________________ +Environment variables for 'randconfig' -KCONFIG_CONFIG +KCONFIG_SEED -------------------------------------------------- -This environment variable can be used to specify a default kernel config -file name to override the default name of ".config". +You can set this to the integer value used to seed the RNG, if you want +to somehow debug the behaviour of the kconfig parser/frontends. +If not set, the current time will be used. -KCONFIG_OVERWRITECONFIG +KCONFIG_PROBABILITY -------------------------------------------------- -If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not -break symlinks when .config is a symlink to somewhere else. +This variable can be used to skew the probabilities. This variable can +be unset or empty, or set to three different formats: + KCONFIG_PROBABILITY y:n split y:m:n split + ----------------------------------------------------------------- + unset or empty 50 : 50 33 : 33 : 34 + N N : 100-N N/2 : N/2 : 100-N + [1] N:M N+M : 100-(N+M) N : M : 100-(N+M) + [2] N:M:L N : 100-N M : L : 100-(M+L) + +where N, M and L are integers (in base 10) in the range [0,100], and so +that: + [1] N+M is in the range [0,100] + [2] M+L is in the range [0,100] + +Examples: + KCONFIG_PROBABILITY=10 + 10% of booleans will be set to 'y', 90% to 'n' + 5% of tristates will be set to 'y', 5% to 'm', 90% to 'n' + KCONFIG_PROBABILITY=15:25 + 40% of booleans will be set to 'y', 60% to 'n' + 15% of tristates will be set to 'y', 25% to 'm', 60% to 'n' + KCONFIG_PROBABILITY=10:15:15 + 10% of booleans will be set to 'y', 90% to 'n' + 15% of tristates will be set to 'y', 15% to 'm', 70% to 'n' + +______________________________________________________________________ +Environment variables for 'silentoldconfig' -KCONFIG_NOTIMESTAMP +KCONFIG_NOSILENTUPDATE -------------------------------------------------- -If this environment variable exists and is non-null, the timestamp line -in generated .config files is omitted. +If this variable has a non-blank value, it prevents silent kernel +config updates (requires explicit updates). KCONFIG_AUTOCONFIG -------------------------------------------------- This environment variable can be set to specify the path & name of the "auto.conf" file. Its default value is "include/config/auto.conf". +KCONFIG_TRISTATE +-------------------------------------------------- +This environment variable can be set to specify the path & name of the +"tristate.conf" file. Its default value is "include/config/tristate.conf". + KCONFIG_AUTOHEADER -------------------------------------------------- This environment variable can be set to specify the path & name of the -"autoconf.h" (header) file. Its default value is "include/linux/autoconf.h". +"autoconf.h" (header) file. +Its default value is "include/generated/autoconf.h". + + +====================================================================== +menuconfig +-------------------------------------------------- + +SEARCHING for CONFIG symbols + +Searching in menuconfig: + + The Search function searches for kernel configuration symbol + names, so you have to know something close to what you are + looking for. + + Example: + /hotplug + This lists all config symbols that contain "hotplug", + e.g., HOTPLUG_CPU, MEMORY_HOTPLUG. + + For search help, enter / followed TAB-TAB-TAB (to highlight + <Help>) and Enter. This will tell you that you can also use + regular expressions (regexes) in the search string, so if you + are not interested in MEMORY_HOTPLUG, you could try + + /^hotplug + + When searching, symbols are sorted thus: + - first, exact matches, sorted alphabetically (an exact match + is when the search matches the complete symbol name); + - then, other matches, sorted alphabetically. + For example: ^ATH.K matches: + ATH5K ATH9K ATH5K_AHB ATH5K_DEBUG [...] ATH6KL ATH6KL_DEBUG + [...] ATH9K_AHB ATH9K_BTCOEX_SUPPORT ATH9K_COMMON [...] + of which only ATH5K and ATH9K match exactly and so are sorted + first (and in alphabetical order), then come all other symbols, + sorted in alphabetical order. ______________________________________________________________________ -menuconfig User Interface Options ----------------------------------------------------------------------- +User interface options for 'menuconfig' + +MENUCONFIG_COLOR +-------------------------------------------------- +It is possible to select different color themes using the variable +MENUCONFIG_COLOR. To select a theme use: + + make MENUCONFIG_COLOR=<theme> menuconfig + +Available themes are: + mono => selects colors suitable for monochrome displays + blackbg => selects a color scheme with black background + classic => theme with blue background. The classic look + bluetitle => a LCD friendly version of classic. (default) + MENUCONFIG_MODE -------------------------------------------------- This mode shows all sub-menus in one large tree. Example: - MENUCONFIG_MODE=single_menu make menuconfig + make MENUCONFIG_MODE=single_menu menuconfig + ====================================================================== xconfig |