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 make listnewconfig 24 25and the config program will list any new symbols, one per line. 26 27 scripts/diffconfig .config.old .config | less 28 29______________________________________________________________________ 30Environment variables for '*config' 31 32KCONFIG_CONFIG 33-------------------------------------------------- 34This environment variable can be used to specify a default kernel config 35file name to override the default name of ".config". 36 37KCONFIG_OVERWRITECONFIG 38-------------------------------------------------- 39If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not 40break symlinks when .config is a symlink to somewhere else. 41 42CONFIG_ 43-------------------------------------------------- 44If you set CONFIG_ in the environment, Kconfig will prefix all symbols 45with its value when saving the configuration, instead of using the default, 46"CONFIG_". 47 48______________________________________________________________________ 49Environment variables for '{allyes/allmod/allno/rand}config' 50 51KCONFIG_ALLCONFIG 52-------------------------------------------------- 53(partially based on lkml email from/by Rob Landley, re: miniconfig) 54-------------------------------------------------- 55The allyesconfig/allmodconfig/allnoconfig/randconfig variants can also 56use the environment variable KCONFIG_ALLCONFIG as a flag or a filename 57that contains config symbols that the user requires to be set to a 58specific value. If KCONFIG_ALLCONFIG is used without a filename where 59KCONFIG_ALLCONFIG == "" or KCONFIG_ALLCONFIG == "1", "make *config" 60checks for a file named "all{yes/mod/no/def/random}.config" 61(corresponding to the *config command that was used) for symbol values 62that are to be forced. If this file is not found, it checks for a 63file named "all.config" to contain forced values. 64 65This enables you to create "miniature" config (miniconfig) or custom 66config files containing just the config symbols that you are interested 67in. Then the kernel config system generates the full .config file, 68including symbols of your miniconfig file. 69 70This 'KCONFIG_ALLCONFIG' file is a config file which contains 71(usually a subset of all) preset config symbols. These variable 72settings are still subject to normal dependency checks. 73 74Examples: 75 KCONFIG_ALLCONFIG=custom-notebook.config make allnoconfig 76or 77 KCONFIG_ALLCONFIG=mini.config make allnoconfig 78or 79 make KCONFIG_ALLCONFIG=mini.config allnoconfig 80 81These examples will disable most options (allnoconfig) but enable or 82disable the options that are explicitly listed in the specified 83mini-config files. 84 85______________________________________________________________________ 86Environment variables for 'randconfig' 87 88KCONFIG_SEED 89-------------------------------------------------- 90You can set this to the integer value used to seed the RNG, if you want 91to somehow debug the behaviour of the kconfig parser/frontends. 92If not set, the current time will be used. 93 94KCONFIG_PROBABILITY 95-------------------------------------------------- 96This variable can be used to skew the probabilities. This variable can 97be unset or empty, or set to three different formats: 98 KCONFIG_PROBABILITY y:n split y:m:n split 99 ----------------------------------------------------------------- 100 unset or empty 50 : 50 33 : 33 : 34 101 N N : 100-N N/2 : N/2 : 100-N 102 [1] N:M N+M : 100-(N+M) N : M : 100-(N+M) 103 [2] N:M:L N : 100-N M : L : 100-(M+L) 104 105where N, M and L are integers (in base 10) in the range [0,100], and so 106that: 107 [1] N+M is in the range [0,100] 108 [2] M+L is in the range [0,100] 109 110Examples: 111 KCONFIG_PROBABILITY=10 112 10% of booleans will be set to 'y', 90% to 'n' 113 5% of tristates will be set to 'y', 5% to 'm', 90% to 'n' 114 KCONFIG_PROBABILITY=15:25 115 40% of booleans will be set to 'y', 60% to 'n' 116 15% of tristates will be set to 'y', 25% to 'm', 60% to 'n' 117 KCONFIG_PROBABILITY=10:15:15 118 10% of booleans will be set to 'y', 90% to 'n' 119 15% of tristates will be set to 'y', 15% to 'm', 70% to 'n' 120 121______________________________________________________________________ 122Environment variables for 'silentoldconfig' 123 124KCONFIG_NOSILENTUPDATE 125-------------------------------------------------- 126If this variable has a non-blank value, it prevents silent kernel 127config updates (requires explicit updates). 128 129KCONFIG_AUTOCONFIG 130-------------------------------------------------- 131This environment variable can be set to specify the path & name of the 132"auto.conf" file. Its default value is "include/config/auto.conf". 133 134KCONFIG_TRISTATE 135-------------------------------------------------- 136This environment variable can be set to specify the path & name of the 137"tristate.conf" file. Its default value is "include/config/tristate.conf". 138 139KCONFIG_AUTOHEADER 140-------------------------------------------------- 141This environment variable can be set to specify the path & name of the 142"autoconf.h" (header) file. 143Its default value is "include/generated/autoconf.h". 144 145 146====================================================================== 147menuconfig 148-------------------------------------------------- 149 150SEARCHING for CONFIG symbols 151 152Searching in menuconfig: 153 154 The Search function searches for kernel configuration symbol 155 names, so you have to know something close to what you are 156 looking for. 157 158 Example: 159 /hotplug 160 This lists all config symbols that contain "hotplug", 161 e.g., HOTPLUG_CPU, MEMORY_HOTPLUG. 162 163 For search help, enter / followed TAB-TAB-TAB (to highlight 164 <Help>) and Enter. This will tell you that you can also use 165 regular expressions (regexes) in the search string, so if you 166 are not interested in MEMORY_HOTPLUG, you could try 167 168 /^hotplug 169 170 When searching, symbols are sorted thus: 171 - first, exact matches, sorted alphabetically (an exact match 172 is when the search matches the complete symbol name); 173 - then, other matches, sorted alphabetically. 174 For example: ^ATH.K matches: 175 ATH5K ATH9K ATH5K_AHB ATH5K_DEBUG [...] ATH6KL ATH6KL_DEBUG 176 [...] ATH9K_AHB ATH9K_BTCOEX_SUPPORT ATH9K_COMMON [...] 177 of which only ATH5K and ATH9K match exactly and so are sorted 178 first (and in alphabetical order), then come all other symbols, 179 sorted in alphabetical order. 180 181______________________________________________________________________ 182User interface options for 'menuconfig' 183 184MENUCONFIG_COLOR 185-------------------------------------------------- 186It is possible to select different color themes using the variable 187MENUCONFIG_COLOR. To select a theme use: 188 189 make MENUCONFIG_COLOR=<theme> menuconfig 190 191Available themes are: 192 mono => selects colors suitable for monochrome displays 193 blackbg => selects a color scheme with black background 194 classic => theme with blue background. The classic look 195 bluetitle => a LCD friendly version of classic. (default) 196 197MENUCONFIG_MODE 198-------------------------------------------------- 199This mode shows all sub-menus in one large tree. 200 201Example: 202 make MENUCONFIG_MODE=single_menu menuconfig 203 204 205====================================================================== 206xconfig 207-------------------------------------------------- 208 209Searching in xconfig: 210 211 The Search function searches for kernel configuration symbol 212 names, so you have to know something close to what you are 213 looking for. 214 215 Example: 216 Ctrl-F hotplug 217 or 218 Menu: File, Search, hotplug 219 220 lists all config symbol entries that contain "hotplug" in 221 the symbol name. In this Search dialog, you may change the 222 config setting for any of the entries that are not grayed out. 223 You can also enter a different search string without having 224 to return to the main menu. 225 226 227====================================================================== 228gconfig 229-------------------------------------------------- 230 231Searching in gconfig: 232 233 None (gconfig isn't maintained as well as xconfig or menuconfig); 234 however, gconfig does have a few more viewing choices than 235 xconfig does. 236 237### 238