1This file contains some assistance for using "make *config". 2 3Use "make help" to list all of the possible configuration targets. 4 5The xconfig ('qconf') and menuconfig ('mconf') programs also 6have embedded help text. Be sure to check it for navigation, 7search, and other general help text. 8 9====================================================================== 10General 11-------------------------------------------------- 12 13New kernel releases often introduce new config symbols. Often more 14important, new kernel releases may rename config symbols. When 15this happens, using a previously working .config file and running 16"make oldconfig" won't necessarily produce a working new kernel 17for you, so you may find that you need to see what NEW kernel 18symbols have been introduced. 19 20To 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 25and the config program will list as (NEW) any new symbols that have 26unknown values. Of course, the .config file is also updated with 27new (default) values, so you can use: 28 29 grep "(NEW)" conf.new 30 31to see the new config symbols or you can use diffconfig to see the 32differences between the previous and new .config files: 33 34 scripts/diffconfig .config.old .config | less 35 36______________________________________________________________________ 37Environment variables for '*config' 38 39KCONFIG_CONFIG 40-------------------------------------------------- 41This environment variable can be used to specify a default kernel config 42file name to override the default name of ".config". 43 44KCONFIG_OVERWRITECONFIG 45-------------------------------------------------- 46If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not 47break symlinks when .config is a symlink to somewhere else. 48 49______________________________________________________________________ 50Environment variables for '{allyes/allmod/allno/rand}config' 51 52KCONFIG_ALLCONFIG 53-------------------------------------------------- 54(partially based on lkml email from/by Rob Landley, re: miniconfig) 55-------------------------------------------------- 56The allyesconfig/allmodconfig/allnoconfig/randconfig variants can also 57use the environment variable KCONFIG_ALLCONFIG as a flag or a filename 58that contains config symbols that the user requires to be set to a 59specific value. If KCONFIG_ALLCONFIG is used without a filename where 60KCONFIG_ALLCONFIG == "" or KCONFIG_ALLCONFIG == "1", "make *config" 61checks for a file named "all{yes/mod/no/def/random}.config" 62(corresponding to the *config command that was used) for symbol values 63that are to be forced. If this file is not found, it checks for a 64file named "all.config" to contain forced values. 65 66This enables you to create "miniature" config (miniconfig) or custom 67config files containing just the config symbols that you are interested 68in. Then the kernel config system generates the full .config file, 69including symbols of your miniconfig file. 70 71This 'KCONFIG_ALLCONFIG' file is a config file which contains 72(usually a subset of all) preset config symbols. These variable 73settings are still subject to normal dependency checks. 74 75Examples: 76 KCONFIG_ALLCONFIG=custom-notebook.config make allnoconfig 77or 78 KCONFIG_ALLCONFIG=mini.config make allnoconfig 79or 80 make KCONFIG_ALLCONFIG=mini.config allnoconfig 81 82These examples will disable most options (allnoconfig) but enable or 83disable the options that are explicitly listed in the specified 84mini-config files. 85 86______________________________________________________________________ 87Environment variables for 'silentoldconfig' 88 89KCONFIG_NOSILENTUPDATE 90-------------------------------------------------- 91If this variable has a non-blank value, it prevents silent kernel 92config updates (requires explicit updates). 93 94KCONFIG_AUTOCONFIG 95-------------------------------------------------- 96This environment variable can be set to specify the path & name of the 97"auto.conf" file. Its default value is "include/config/auto.conf". 98 99KCONFIG_TRISTATE 100-------------------------------------------------- 101This environment variable can be set to specify the path & name of the 102"tristate.conf" file. Its default value is "include/config/tristate.conf". 103 104KCONFIG_AUTOHEADER 105-------------------------------------------------- 106This environment variable can be set to specify the path & name of the 107"autoconf.h" (header) file. 108Its default value is "include/generated/autoconf.h". 109 110 111====================================================================== 112menuconfig 113-------------------------------------------------- 114 115SEARCHING for CONFIG symbols 116 117Searching in menuconfig: 118 119 The Search function searches for kernel configuration symbol 120 names, so you have to know something close to what you are 121 looking for. 122 123 Example: 124 /hotplug 125 This lists all config symbols that contain "hotplug", 126 e.g., HOTPLUG, HOTPLUG_CPU, MEMORY_HOTPLUG. 127 128 For search help, enter / followed TAB-TAB-TAB (to highlight 129 <Help>) and Enter. This will tell you that you can also use 130 regular expressions (regexes) in the search string, so if you 131 are not interested in MEMORY_HOTPLUG, you could try 132 133 /^hotplug 134 135______________________________________________________________________ 136User interface options for 'menuconfig' 137 138MENUCONFIG_COLOR 139-------------------------------------------------- 140It is possible to select different color themes using the variable 141MENUCONFIG_COLOR. To select a theme use: 142 143 make MENUCONFIG_COLOR=<theme> menuconfig 144 145Available themes are: 146 mono => selects colors suitable for monochrome displays 147 blackbg => selects a color scheme with black background 148 classic => theme with blue background. The classic look 149 bluetitle => a LCD friendly version of classic. (default) 150 151MENUCONFIG_MODE 152-------------------------------------------------- 153This mode shows all sub-menus in one large tree. 154 155Example: 156 make MENUCONFIG_MODE=single_menu menuconfig 157 158 159====================================================================== 160xconfig 161-------------------------------------------------- 162 163Searching in xconfig: 164 165 The Search function searches for kernel configuration symbol 166 names, so you have to know something close to what you are 167 looking for. 168 169 Example: 170 Ctrl-F hotplug 171 or 172 Menu: File, Search, hotplug 173 174 lists all config symbol entries that contain "hotplug" in 175 the symbol name. In this Search dialog, you may change the 176 config setting for any of the entries that are not grayed out. 177 You can also enter a different search string without having 178 to return to the main menu. 179 180 181====================================================================== 182gconfig 183-------------------------------------------------- 184 185Searching in gconfig: 186 187 None (gconfig isn't maintained as well as xconfig or menuconfig); 188 however, gconfig does have a few more viewing choices than 189 xconfig does. 190 191### 192