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-rw-r--r--Documentation/kbuild/00-INDEX6
-rw-r--r--Documentation/kbuild/kbuild.txt126
-rw-r--r--Documentation/kbuild/kconfig.txt188
3 files changed, 319 insertions, 1 deletions
diff --git a/Documentation/kbuild/00-INDEX b/Documentation/kbuild/00-INDEX
index 114644285454..e8d2b6d83a3d 100644
--- a/Documentation/kbuild/00-INDEX
+++ b/Documentation/kbuild/00-INDEX
@@ -1,5 +1,9 @@
100-INDEX 100-INDEX
2 - this file: info on the kernel build process 2 - this file: info on the kernel build process
3kbuild.txt
4 - developer information on kbuild
5kconfig.txt
6 - usage help for make *config
3kconfig-language.txt 7kconfig-language.txt
4 - specification of Config Language, the language in Kconfig files 8 - specification of Config Language, the language in Kconfig files
5makefiles.txt 9makefiles.txt
diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt
new file mode 100644
index 000000000000..51771847e816
--- /dev/null
+++ b/Documentation/kbuild/kbuild.txt
@@ -0,0 +1,126 @@
1Environment variables
2
3KCPPFLAGS
4--------------------------------------------------
5Additional options to pass when preprocessing. The preprocessing options
6will be used in all cases where kbuild do preprocessing including
7building C files and assembler files.
8
9KAFLAGS
10--------------------------------------------------
11Additional options to the assembler.
12
13KCFLAGS
14--------------------------------------------------
15Additional options to the C compiler.
16
17KBUILD_VERBOSE
18--------------------------------------------------
19Set the kbuild verbosity. Can be assinged same values as "V=...".
20See make help for the full list.
21Setting "V=..." takes precedence over KBUILD_VERBOSE.
22
23KBUILD_EXTMOD
24--------------------------------------------------
25Set the directory to look for the kernel source when building external
26modules.
27The directory can be specified in several ways:
281) Use "M=..." on the command line
292) Environmnet variable KBUILD_EXTMOD
303) Environmnet variable SUBDIRS
31The possibilities are listed in the order they take precedence.
32Using "M=..." will always override the others.
33
34KBUILD_OUTPUT
35--------------------------------------------------
36Specify the output directory when building the kernel.
37The output directory can also be specificed using "O=...".
38Setting "O=..." takes precedence over KBUILD_OUTPUT
39
40ARCH
41--------------------------------------------------
42Set ARCH to the architecture to be built.
43In most cases the name of the architecture is the same as the
44directory name found in the arch/ directory.
45But some architectures suach as x86 and sparc has aliases.
46x86: i386 for 32 bit, x86_64 for 64 bit
47sparc: sparc for 32 bit, sparc64 for 64 bit
48
49CROSS_COMPILE
50--------------------------------------------------
51Specify an optional fixed part of the binutils filename.
52CROSS_COMPILE can be a part of the filename or the full path.
53
54CROSS_COMPILE is also used for ccache is some setups.
55
56CF
57--------------------------------------------------
58Additional options for sparse.
59CF is often used on the command-line like this:
60
61 make CF=-Wbitwise C=2
62
63INSTALL_PATH
64--------------------------------------------------
65INSTALL_PATH specifies where to place the updated kernel and system map
66images. Default is /boot, but you can set it to other values
67
68
69MODLIB
70--------------------------------------------------
71Specify where to install modules.
72The default value is:
73
74 $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
75
76The value can be overridden in which case the default value is ignored.
77
78INSTALL_MOD_PATH
79--------------------------------------------------
80INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
81relocations required by build roots. This is not defined in the
82makefile but the argument can be passed to make if needed.
83
84INSTALL_MOD_STRIP
85--------------------------------------------------
86INSTALL_MOD_STRIP, if defined, will cause modules to be
87stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
88the default option --strip-debug will be used. Otherwise,
89INSTALL_MOD_STRIP will used as the options to the strip command.
90
91INSTALL_FW_PATH
92--------------------------------------------------
93INSTALL_FW_PATH specify where to install the firmware blobs.
94The default value is:
95
96 $(INSTALL_MOD_PATH)/lib/firmware
97
98The value can be overridden in which case the default value is ignored.
99
100INSTALL_HDR_PATH
101--------------------------------------------------
102INSTALL_HDR_PATH specify where to install user space headers when
103executing "make headers_*".
104The default value is:
105
106 $(objtree)/usr
107
108$(objtree) is the directory where output files are saved.
109The output directory is often set using "O=..." on the commandline.
110
111The value can be overridden in which case the default value is ignored.
112
113KBUILD_MODPOST_WARN
114--------------------------------------------------
115KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined
116symbols in the final module linking stage.
117
118KBUILD_MODPOST_FINAL
119--------------------------------------------------
120KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
121This is solely usefull to speed up test compiles.
122
123KBUILD_EXTRA_SYMBOLS
124--------------------------------------------------
125For modules use symbols from another modules.
126See more details in modules.txt.
diff --git a/Documentation/kbuild/kconfig.txt b/Documentation/kbuild/kconfig.txt
new file mode 100644
index 000000000000..26a7c0a93193
--- /dev/null
+++ b/Documentation/kbuild/kconfig.txt
@@ -0,0 +1,188 @@
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 'diff' the previous and
32new .config files to see the differences:
33
34 diff .config.old .config | less
35
36(Yes, we need something better here.)
37
38
39======================================================================
40menuconfig
41--------------------------------------------------
42
43SEARCHING for CONFIG symbols
44
45Searching 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______________________________________________________________________
65Color Themes for 'menuconfig'
66
67It is possible to select different color themes using the variable
68MENUCONFIG_COLOR. To select a theme use:
69
70 make MENUCONFIG_COLOR=<theme> menuconfig
71
72Available 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______________________________________________________________________
79Environment variables in 'menuconfig'
80
81KCONFIG_ALLCONFIG
82--------------------------------------------------
83(partially based on lkml email from/by Rob Landley, re: miniconfig)
84--------------------------------------------------
85The allyesconfig/allmodconfig/allnoconfig/randconfig variants can
86also use the environment variable KCONFIG_ALLCONFIG as a flag or a
87filename that contains config symbols that the user requires to be
88set to a specific value. If KCONFIG_ALLCONFIG is used without a
89filename, "make *config" checks for a file named
90"all{yes/mod/no/random}.config" (corresponding to the *config command
91that was used) for symbol values that are to be forced. If this file
92is not found, it checks for a file named "all.config" to contain forced
93values.
94
95This enables you to create "miniature" config (miniconfig) or custom
96config files containing just the config symbols that you are interested
97in. Then the kernel config system generates the full .config file,
98including dependencies of your miniconfig file, based on the miniconfig
99file.
100
101This 'KCONFIG_ALLCONFIG' file is a config file which contains
102(usually a subset of all) preset config symbols. These variable
103settings are still subject to normal dependency checks.
104
105Examples:
106 KCONFIG_ALLCONFIG=custom-notebook.config make allnoconfig
107or
108 KCONFIG_ALLCONFIG=mini.config make allnoconfig
109or
110 make KCONFIG_ALLCONFIG=mini.config allnoconfig
111
112These examples will disable most options (allnoconfig) but enable or
113disable the options that are explicitly listed in the specified
114mini-config files.
115
116KCONFIG_NOSILENTUPDATE
117--------------------------------------------------
118If this variable has a non-blank value, it prevents silent kernel
119config udpates (requires explicit updates).
120
121KCONFIG_CONFIG
122--------------------------------------------------
123This environment variable can be used to specify a default kernel config
124file name to override the default name of ".config".
125
126KCONFIG_OVERWRITECONFIG
127--------------------------------------------------
128If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not
129break symlinks when .config is a symlink to somewhere else.
130
131KCONFIG_NOTIMESTAMP
132--------------------------------------------------
133If this environment variable exists and is non-null, the timestamp line
134in generated .config files is omitted.
135
136KCONFIG_AUTOCONFIG
137--------------------------------------------------
138This 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
141KCONFIG_AUTOHEADER
142--------------------------------------------------
143This 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______________________________________________________________________
147menuconfig User Interface Options
148----------------------------------------------------------------------
149MENUCONFIG_MODE
150--------------------------------------------------
151This mode shows all sub-menus in one large tree.
152
153Example:
154 MENUCONFIG_MODE=single_menu make menuconfig
155
156======================================================================
157xconfig
158--------------------------------------------------
159
160Searching 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======================================================================
179gconfig
180--------------------------------------------------
181
182Searching 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###