8 # To see a list of typical targets execute "make help"
9 # More info can be located in ./README
10 # Comments in this file are targeted only to the developer, do not
11 # expect to learn how to build the kernel reading this file.
13 # Do not print "Entering directory ..."
14 MAKEFLAGS += --no-print-directory
16 # We are using a recursive build, so we need to do a little thinking
17 # to get the ordering right.
19 # Most importantly: sub-Makefiles should only ever modify files in
20 # their own directory. If in some directory we have a dependency on
21 # a file in another dir (which doesn't happen often, but it's often
22 # unavoidable when linking the built-in.o targets which finally
23 # turn into busybox), we will call a sub make in that other dir, and
24 # after that we are sure that everything which is in that other dir
27 # The only cases where we need to modify files which have global
28 # effects are thus separated out and done before the recursive
29 # descending is started. They are now explicitly listed as the
32 # To put more focus on warnings, be less verbose as default
33 # Use 'make V=1' to see the full commands
36 ifeq ("$(origin V)", "command line")
44 # Call sparse as part of compilation of C files
45 # Use 'make C=1' to enable sparse checking
48 ifeq ("$(origin C)", "command line")
49 KBUILD_CHECKSRC = $(C)
52 ifndef KBUILD_CHECKSRC
56 # Use make M=dir to specify directory of external module to build
57 # Old syntax make ... SUBDIRS=$PWD is still supported
58 # Setting the environment variable KBUILD_EXTMOD take precedence
60 KBUILD_EXTMOD ?= $(SUBDIRS)
63 ifeq ("$(origin M)", "command line")
69 # kbuild supports saving output files in a separate directory.
70 # To locate output files in a separate directory two syntaxes are supported.
71 # In both cases the working directory must be the root of the kernel src.
73 # Use "make O=dir/to/store/output/files/"
75 # 2) Set KBUILD_OUTPUT
76 # Set the environment variable KBUILD_OUTPUT to point to the directory
77 # where the output files shall be placed.
78 # export KBUILD_OUTPUT=dir/to/store/output/files/
81 # The O= assignment takes precedence over the KBUILD_OUTPUT environment
85 # KBUILD_SRC is set on invocation of make in OBJ directory
86 # KBUILD_SRC is not intended to be used by the regular user (for now)
89 # OK, Make called in directory where kernel src resides
90 # Do we want to locate output files in a separate directory?
92 ifeq ("$(origin O)", "command line")
97 # That's our default target when none is given on the command line
101 ifneq ($(KBUILD_OUTPUT),)
102 # Invoke a second make in the output directory, passing relevant variables
103 # check that the output directory actually exists
104 saved-output := $(KBUILD_OUTPUT)
105 KBUILD_OUTPUT := $(shell cd $(KBUILD_OUTPUT) && /bin/pwd)
106 $(if $(KBUILD_OUTPUT),, \
107 $(error output directory "$(saved-output)" does not exist))
109 PHONY += $(MAKECMDGOALS)
111 $(filter-out _all,$(MAKECMDGOALS)) _all:
112 $(if $(KBUILD_VERBOSE:1=),@)$(MAKE) -C $(KBUILD_OUTPUT) \
113 KBUILD_SRC=$(CURDIR) \
114 KBUILD_EXTMOD="$(KBUILD_EXTMOD)" -f $(CURDIR)/Makefile $@
116 # Leave processing to above invocation of make
118 endif # ifneq ($(KBUILD_OUTPUT),)
119 endif # ifeq ($(KBUILD_SRC),)
121 # We process the rest of the Makefile if this is the final invocation of make
122 ifeq ($(skip-makefile),)
124 # If building an external module we do not care about the all: rule
125 # but instead _all depend on modules
127 ifeq ($(KBUILD_EXTMOD),)
133 srctree := $(if $(KBUILD_SRC),$(KBUILD_SRC),$(CURDIR))
135 # FIXME - TOPDIR is obsolete, use srctree/objtree
140 VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
142 export srctree objtree VPATH TOPDIR
145 # Cross compiling and selecting different set of gcc/bin-utils
146 # ---------------------------------------------------------------------------
148 # When performing cross compilation for other architectures ARCH shall be set
149 # to the target architecture. (See arch/* for the possibilities).
150 # ARCH can be set during invocation of make:
152 # Another way is to have ARCH set in the environment.
153 # The default ARCH is the host where make is executed.
155 # CROSS_COMPILE specify the prefix used for all executables used
156 # during compilation. Only gcc and related bin-utils executables
157 # are prefixed with $(CROSS_COMPILE).
158 # CROSS_COMPILE can be set on the command line
159 # make CROSS_COMPILE=ia64-linux-
160 # Alternatively CROSS_COMPILE can be set in the environment.
161 # Default value for CROSS_COMPILE is not to prefix executables
162 # Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
165 # bbox: we may have CONFIG_CROSS_COMPILER_PREFIX in .config,
166 # and it has not been included yet... thus using an awkward syntax.
167 ifeq ($(CROSS_COMPILE),)
168 CROSS_COMPILE := $(shell grep ^CONFIG_CROSS_COMPILER_PREFIX .config 2>/dev/null)
169 CROSS_COMPILE := $(subst CONFIG_CROSS_COMPILER_PREFIX=,,$(CROSS_COMPILE))
170 CROSS_COMPILE := $(subst ",,$(CROSS_COMPILE))
174 # SUBARCH tells the usermode build what the underlying arch is. That is set
175 # first, and if a usermode build is happening, the "ARCH=um" on the command
176 # line overrides the setting of ARCH below. If a native build is happening,
177 # then ARCH is assigned, getting whatever value it gets normally, and
178 # SUBARCH is subsequently ignored.
180 ifneq ($(CROSS_COMPILE),)
181 SUBARCH := $(shell echo $(CROSS_COMPILE) | cut -d- -f1)
183 SUBARCH := $(shell uname -m)
185 SUBARCH := $(shell echo $(SUBARCH) | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
186 -e s/arm.*/arm/ -e s/sa110/arm/ \
187 -e s/s390x/s390/ -e s/parisc64/parisc/ \
188 -e s/ppc.*/powerpc/ -e s/mips.*/mips/ )
192 # Architecture as present in compile.h
193 UTS_MACHINE := $(ARCH)
195 # SHELL used by kbuild
196 CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
197 else if [ -x /bin/bash ]; then echo /bin/bash; \
198 else echo sh; fi ; fi)
200 # Decide whether to build built-in, modular, or both.
201 # Normally, just do built-in.
206 # If we have only "make modules", don't compile built-in objects.
207 # When we're building modules with modversions, we need to consider
208 # the built-in objects during the descend as well, in order to
209 # make sure the checksums are uptodate before we record them.
211 ifeq ($(MAKECMDGOALS),modules)
212 KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
215 # If we have "make <whatever> modules", compile modules
216 # in addition to whatever we do anyway.
217 # Just "make" or "make all" shall build modules as well
219 ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
223 ifeq ($(MAKECMDGOALS),)
227 export KBUILD_MODULES KBUILD_BUILTIN
228 export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
231 # ---------------------------------------------------------------------------
233 # Normally, we echo the whole command before executing it. By making
234 # that echo $($(quiet)$(cmd)), we now have the possibility to set
235 # $(quiet) to choose other forms of output instead, e.g.
237 # quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
238 # cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
240 # If $(quiet) is empty, the whole command will be printed.
241 # If it is set to "quiet_", only the short version will be printed.
242 # If it is set to "silent_", nothing wil be printed at all, since
243 # the variable $(silent_cmd_cc_o_c) doesn't exist.
245 # A simple variant is to prefix commands with $(Q) - that's useful
246 # for commands that shall be hidden in non-verbose mode.
250 # If KBUILD_VERBOSE equals 0 then the above command will be hidden.
251 # If KBUILD_VERBOSE equals 1 then the above command is displayed.
253 ifeq ($(KBUILD_VERBOSE),1)
261 # If the user is running make -s (silent mode), suppress echoing of
264 ifneq ($(findstring s,$(MAKEFLAGS)),)
268 export quiet Q KBUILD_VERBOSE
271 # Look for make include files relative to root of kernel src
272 MAKEFLAGS += --include-dir=$(srctree)
278 # We need some generic definitions
279 include $(srctree)/scripts/Kbuild.include
281 HOSTCFLAGS += $(call hostcc-option,-Wall -Wstrict-prototypes -O2 -fomit-frame-pointer,)
284 # For maximum performance (+ possibly random breakage, uncomment
289 # Make variables (CC, etc...)
291 AS = $(CROSS_COMPILE)as
292 CC = $(CROSS_COMPILE)gcc
295 AR = $(CROSS_COMPILE)ar
296 NM = $(CROSS_COMPILE)nm
297 STRIP = $(CROSS_COMPILE)strip
298 OBJCOPY = $(CROSS_COMPILE)objcopy
299 OBJDUMP = $(CROSS_COMPILE)objdump
301 GENKSYMS = scripts/genksyms/genksyms
302 DEPMOD = /sbin/depmod
303 KALLSYMS = scripts/kallsyms
307 CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ -Wbitwise $(CF)
309 CFLAGS_MODULE = $(MODFLAGS)
310 AFLAGS_MODULE = $(MODFLAGS)
316 # Use LINUXINCLUDE when you must reference the include/ directory.
317 # Needed to be compatible with the O= option
319 # Added only to final link stage of busybox binary
320 CFLAGS_busybox := $(CFLAGS_busybox)
321 CPPFLAGS := $(CPPFLAGS)
323 LDFLAGS := $(LDFLAGS)
326 # Read KERNELRELEASE from .kernelrelease (if it exists)
327 KERNELRELEASE = $(shell cat .kernelrelease 2> /dev/null)
328 KERNELVERSION = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)
330 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION \
331 ARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC \
332 CPP AR NM STRIP OBJCOPY OBJDUMP MAKE AWK GENKSYMS PERL UTS_MACHINE \
333 HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
335 export CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
336 export CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
337 export AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
340 # When compiling out-of-tree modules, put MODVERDIR in the module
341 # tree rather than in the kernel tree. The kernel tree might
343 export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
345 # Files to ignore in find ... statements
347 RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o -name CVS -o -name .pc -o -name .hg -o -name .git \) -prune -o
348 export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn --exclude CVS --exclude .pc --exclude .hg --exclude .git
350 # ===========================================================================
351 # Rules shared between *config targets and build targets
353 # Basic helpers built in scripts/
354 PHONY += scripts_basic
356 $(Q)$(MAKE) $(build)=scripts/basic
358 # To avoid any implicit rule to kick in, define an empty command.
359 scripts/basic/%: scripts_basic ;
361 # bbox: we have helpers in applets/
362 # we depend on scripts_basic, since scripts/basic/fixdep
363 # must be built before any other host prog
365 applets_dir: scripts_basic
366 $(Q)$(MAKE) $(build)=applets
368 applets/%: applets_dir ;
370 PHONY += outputmakefile
371 # outputmakefile generates a Makefile in the output directory, if using a
372 # separate output directory. This allows convenient use of make in the
375 ifneq ($(KBUILD_SRC),)
376 $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
377 $(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
380 # This target generates Kbuild's and Config.in's from *.c files
381 PHONY += gen_build_files
383 $(Q)$(srctree)/scripts/gen_build_files.sh $(srctree) $(objtree)
385 # To make sure we do not include .config for any of the *config targets
386 # catch them early, and hand them over to scripts/kconfig/Makefile
387 # It is allowed to specify more targets when calling make, including
388 # mixing *config targets and build targets.
389 # For example 'make oldconfig all'.
390 # Detect when mixed targets is specified, and make a second invocation
391 # of make so .config is not included in this case either (for *config).
393 no-dot-config-targets := clean mrproper distclean \
394 cscope TAGS tags help %docs
395 #bbox# check% is removed from above
401 ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
402 ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
407 ifeq ($(KBUILD_EXTMOD),)
408 ifneq ($(filter config %config,$(MAKECMDGOALS)),)
410 ifneq ($(filter-out config %config,$(MAKECMDGOALS)),)
416 ifeq ($(mixed-targets),1)
417 # ===========================================================================
418 # We're called with mixed targets (*config and build targets).
419 # Handle them one by one.
422 $(Q)$(MAKE) -C $(srctree) KBUILD_SRC= $@
425 ifeq ($(config-targets),1)
426 # ===========================================================================
427 # *config targets only - make sure prerequisites are updated, and descend
428 # in scripts/kconfig to make the *config target
430 # Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
431 # KBUILD_DEFCONFIG may point out an alternative default configuration
432 # used for 'make defconfig'
433 -include $(srctree)/arch/$(ARCH)/Makefile
434 export KBUILD_DEFCONFIG
436 config %config: scripts_basic outputmakefile gen_build_files FORCE
438 $(Q)$(MAKE) $(build)=scripts/kconfig $@
439 $(Q)$(MAKE) -C $(srctree) KBUILD_SRC= .kernelrelease
442 # ===========================================================================
443 # Build targets only - this includes busybox, arch specific targets, clean
444 # targets and others. In general all targets except *config targets.
446 ifeq ($(KBUILD_EXTMOD),)
447 # Additional helpers built in scripts/
448 # Carefully list dependencies so we do not try to build scripts twice
451 scripts: gen_build_files scripts_basic include/config/MARKER
452 $(Q)$(MAKE) $(build)=$(@)
454 scripts_basic: include/autoconf.h
456 # Objects we will link into busybox / subdirs we need to visit
462 archival/libunarchive/ \
465 coreutils/libcoreutils/ \
478 networking/libiproute/ \
487 util-linux/volume_id/ \
489 endif # KBUILD_EXTMOD
491 ifeq ($(dot-config),1)
492 # In this section, we need .config
494 # Read in dependencies to all Kconfig* files, make sure to run
495 # oldconfig if changes are detected.
500 # If .config needs to be updated, it will be done via the dependency
501 # that autoconf has on .config.
502 # To avoid any implicit rule to kick in, define an empty command
503 .config .kconfig.d: ;
505 # Now we can define CFLAGS etc according to .config
506 include $(srctree)/Makefile.flags
508 # If .config is newer than include/autoconf.h, someone tinkered
509 # with it and forgot to run make oldconfig.
510 # If kconfig.d is missing then we are probarly in a cleaned tree so
511 # we execute the config step to be sure to catch updated Kconfig files
512 include/autoconf.h: .kconfig.d .config
513 $(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
516 # Dummy target needed, because used as prerequisite
517 include/autoconf.h: ;
520 # The all: target is the default when no target is given on the
522 # This allow a user to issue only 'make' to build a kernel including modules
523 # Defaults busybox but it is usually overridden in the arch makefile
526 -include $(srctree)/arch/$(ARCH)/Makefile
528 # arch Makefile may override CC so keep this after arch Makefile is included
529 #bbox# NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
530 CHECKFLAGS += $(NOSTDINC_FLAGS)
532 # Default kernel image to build when no specific target is given.
533 # KBUILD_IMAGE may be overruled on the commandline or
534 # set in the environment
535 # Also any assignments in arch/$(ARCH)/Makefile take precedence over
537 export KBUILD_IMAGE ?= busybox
540 # INSTALL_PATH specifies where to place the updated kernel and system map
541 # images. Default is /boot, but you can set it to other values
542 export INSTALL_PATH ?= /boot
545 # INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
546 # relocations required by build roots. This is not defined in the
547 # makefile but the arguement can be passed to make if needed.
550 MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
554 ifeq ($(KBUILD_EXTMOD),)
555 busybox-dirs := $(patsubst %/,%,$(filter %/, $(core-y) $(core-m) $(libs-y) $(libs-m)))
557 busybox-alldirs := $(sort $(busybox-dirs) $(patsubst %/,%,$(filter %/, \
558 $(core-n) $(core-) $(libs-n) $(libs-) \
561 core-y := $(patsubst %/, %/built-in.o, $(core-y))
562 libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
563 libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
564 libs-y := $(libs-y1) $(libs-y2)
567 # ---------------------------------------------------------------------------
568 # busybox is build from the objects selected by $(busybox-init) and
569 # $(busybox-main). Most are built-in.o files from top-level directories
570 # in the kernel tree, others are specified in arch/$(ARCH)Makefile.
571 # Ordering when linking is important, and $(busybox-init) must be first.
576 # +-< $(busybox-init)
577 # | +--< init/version.o + more
579 # +--< $(busybox-main)
580 # | +--< driver/built-in.o mm/built-in.o + more
582 # +-< kallsyms.o (see description in CONFIG_KALLSYMS section)
584 # busybox version (uname -v) cannot be updated during normal
585 # descending-into-subdirs phase since we do not yet know if we need to
587 # Therefore this step is delayed until just before final link of busybox -
588 # except in the kallsyms case where it is done just before adding the
589 # symbols to the kernel.
591 # System.map is generated to document addresses of all kernel symbols
593 busybox-all := $(core-y) $(libs-y)
595 # Rule to link busybox - also used during CONFIG_KALLSYMS
596 # May be overridden by arch/$(ARCH)/Makefile
597 quiet_cmd_busybox__ ?= LINK $@
598 cmd_busybox__ ?= $(srctree)/scripts/trylink \
601 "$(CFLAGS) $(CFLAGS_busybox)" \
602 "$(LDFLAGS) $(EXTRA_LDFLAGS)" \
607 # Generate System.map
608 quiet_cmd_sysmap = SYSMAP
609 cmd_sysmap = $(CONFIG_SHELL) $(srctree)/scripts/mksysmap
612 # If CONFIG_KALLSYMS is set .version is already updated
613 # Generate System.map and verify that the content is consistent
614 # Use + in front of the busybox_version rule to silent warning with make -j2
615 # First command is ':' to allow us to use + in front of the rule
616 define rule_busybox__
618 $(call cmd,busybox__)
619 $(Q)echo 'cmd_$@ := $(cmd_busybox__)' > $(@D)/.$(@F).cmd
623 ifdef CONFIG_KALLSYMS
624 # Generate section listing all symbols and add it into busybox $(kallsyms.o)
625 # It's a three stage process:
626 # o .tmp_busybox1 has all symbols and sections, but __kallsyms is
628 # Running kallsyms on that gives us .tmp_kallsyms1.o with
629 # the right size - busybox version (uname -v) is updated during this step
630 # o .tmp_busybox2 now has a __kallsyms section of the right size,
631 # but due to the added section, some addresses have shifted.
632 # From here, we generate a correct .tmp_kallsyms2.o
633 # o The correct .tmp_kallsyms2.o is linked into the final busybox.
634 # o Verify that the System.map from busybox matches the map from
635 # .tmp_busybox2, just in case we did not generate kallsyms correctly.
636 # o If CONFIG_KALLSYMS_EXTRA_PASS is set, do an extra pass using
637 # .tmp_busybox3 and .tmp_kallsyms3.o. This is only meant as a
638 # temporary bypass to allow the kernel to be built while the
639 # maintainers work out what went wrong with kallsyms.
641 ifdef CONFIG_KALLSYMS_EXTRA_PASS
647 kallsyms.o := .tmp_kallsyms$(last_kallsyms).o
649 define verify_kallsyms
650 $(Q)$(if $($(quiet)cmd_sysmap), \
651 echo ' $($(quiet)cmd_sysmap) .tmp_System.map' &&) \
652 $(cmd_sysmap) .tmp_busybox$(last_kallsyms) .tmp_System.map
653 $(Q)cmp -s System.map .tmp_System.map || \
654 (echo Inconsistent kallsyms data; \
655 echo Try setting CONFIG_KALLSYMS_EXTRA_PASS; \
656 rm .tmp_kallsyms* ; /bin/false )
659 # Update busybox version before link
660 # Use + in front of this rule to silent warning about make -j1
661 # First command is ':' to allow us to use + in front of this rule
662 cmd_ksym_ld = $(cmd_busybox__)
665 +$(call cmd,busybox_version)
666 $(call cmd,busybox__)
667 $(Q)echo 'cmd_$@ := $(cmd_busybox__)' > $(@D)/.$(@F).cmd
670 # Generate .S file with all kernel symbols
671 quiet_cmd_kallsyms = KSYM $@
672 cmd_kallsyms = $(NM) -n $< | $(KALLSYMS) \
673 $(if $(CONFIG_KALLSYMS_ALL),--all-symbols) > $@
675 .tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
676 $(call if_changed_dep,as_o_S)
678 .tmp_kallsyms%.S: .tmp_busybox% $(KALLSYMS)
681 # .tmp_busybox1 must be complete except kallsyms, so update busybox version
682 .tmp_busybox1: $(busybox-lds) $(busybox-all) FORCE
683 $(call if_changed_rule,ksym_ld)
685 .tmp_busybox2: $(busybox-lds) $(busybox-all) .tmp_kallsyms1.o FORCE
686 $(call if_changed,busybox__)
688 .tmp_busybox3: $(busybox-lds) $(busybox-all) .tmp_kallsyms2.o FORCE
689 $(call if_changed,busybox__)
691 # Needs to visit scripts/ before $(KALLSYMS) can be used.
692 $(KALLSYMS): scripts ;
694 # Generate some data for debugging strange kallsyms problems
695 debug_kallsyms: .tmp_map$(last_kallsyms)
697 .tmp_map%: .tmp_busybox% FORCE
698 ($(OBJDUMP) -h $< | $(AWK) '/^ +[0-9]/{print $$4 " 0 " $$2}'; $(NM) $<) | sort > $@
704 endif # ifdef CONFIG_KALLSYMS
706 # busybox image - including updated kernel symbols
707 busybox_unstripped: $(busybox-all) FORCE
708 $(call if_changed_rule,busybox__)
709 $(Q)rm -f .old_version
711 busybox: busybox_unstripped
712 ifeq ($(SKIP_STRIP),y)
715 $(Q)$(STRIP) -s --remove-section=.note --remove-section=.comment \
716 busybox_unstripped -o $@
717 # strip is confused by PIE executable and does not set exec bits
721 # The actual objects are generated when descending,
722 # make sure no implicit rule kicks in
723 $(sort $(busybox-all)): $(busybox-dirs) ;
725 # Handle descending into subdirectories listed in $(busybox-dirs)
726 # Preset locale variables to speed up the build process. Limit locale
727 # tweaks to this spot to avoid wrong language settings when running
728 # make menuconfig etc.
729 # Error messages still appears in the original language
731 PHONY += $(busybox-dirs)
732 $(busybox-dirs): prepare scripts
733 $(Q)$(MAKE) $(build)=$@
735 # Build the kernel release string
736 # The KERNELRELEASE is stored in a file named .kernelrelease
737 # to be used when executing for example make install or make modules_install
739 # Take the contents of any files called localversion* and the config
740 # variable CONFIG_LOCALVERSION and append them to KERNELRELEASE.
741 # LOCALVERSION from the command line override all of this
744 space := $(nullstring) # end of line
746 ___localver = $(objtree)/localversion* $(srctree)/localversion*
747 __localver = $(sort $(wildcard $(___localver)))
748 # skip backup files (containing '~')
749 _localver = $(foreach f, $(__localver), $(if $(findstring ~, $(f)),,$(f)))
751 localver = $(subst $(space),, \
752 $(shell cat /dev/null $(_localver)) \
753 $(patsubst "%",%,$(CONFIG_LOCALVERSION)))
755 # If CONFIG_LOCALVERSION_AUTO is set scripts/setlocalversion is called
756 # and if the SCM is know a tag from the SCM is appended.
757 # The appended tag is determinded by the SCM used.
759 # Currently, only git is supported.
760 # Other SCMs can edit scripts/setlocalversion and add the appropriate
762 ifdef _BB_DISABLED_CONFIG_LOCALVERSION_AUTO
763 _localver-auto = $(shell $(CONFIG_SHELL) \
764 $(srctree)/scripts/setlocalversion $(srctree))
765 localver-auto = $(LOCALVERSION)$(_localver-auto)
768 localver-full = $(localver)$(localver-auto)
770 # Store (new) KERNELRELASE string in .kernelrelease
771 kernelrelease = $(KERNELVERSION)$(localver-full)
772 .kernelrelease: FORCE
774 $(Q)echo $(kernelrelease) > $@
777 # Things we need to do before we recursively start building the kernel
778 # or the modules are listed in "prepare".
779 # A multi level approach is used. prepareN is processed before prepareN-1.
780 # archprepare is used in arch Makefiles and when processed asm symlink,
781 # version.h and scripts_basic is processed / created.
783 # Listed in dependency order
784 PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
786 # prepare-all is deprecated, use prepare as valid replacement
789 # prepare3 is used to check if we are building in a separate output directory,
791 # 1) Check that make has not been executed in the kernel src $(srctree)
792 # 2) Create the include2 directory, used for the second asm symlink
793 prepare3: .kernelrelease
794 ifneq ($(KBUILD_SRC),)
795 @echo ' Using $(srctree) as source for busybox'
796 $(Q)if [ -f $(srctree)/.config ]; then \
797 echo " $(srctree) is not clean, please run 'make mrproper'";\
798 echo " in the '$(srctree)' directory.";\
801 $(Q)if [ ! -d include2 ]; then mkdir -p include2; fi;
802 $(Q)ln -fsn $(srctree)/include/asm-$(ARCH) include2/asm
805 # prepare2 creates a makefile if using a separate output directory
806 prepare2: prepare3 outputmakefile
808 prepare1: prepare2 include/config/MARKER
809 ifneq ($(KBUILD_MODULES),)
810 $(Q)mkdir -p $(MODVERDIR)
811 $(Q)rm -f $(MODVERDIR)/*
814 archprepare: prepare1 scripts_basic applets_dir
816 prepare0: archprepare FORCE
817 $(Q)$(MAKE) $(build)=.
819 # All the preparing..
820 prepare prepare-all: prepare0
822 # Leave this as default for preprocessing busybox.lds.S, which is now
823 # done in arch/$(ARCH)/kernel/Makefile
825 export CPPFLAGS_busybox.lds += -P -C -U$(ARCH)
827 # FIXME: The asm symlink changes when $(ARCH) changes. That's
828 # hard to detect, but I suppose "make mrproper" is a good idea
829 # before switching between archs anyway.
832 #bbox# @echo ' SYMLINK $@ -> include/asm-$(ARCH)'
833 #bbox# $(Q)if [ ! -d include ]; then mkdir -p include; fi;
834 #bbox# @ln -fsn asm-$(ARCH) $@
836 # Split autoconf.h into include/linux/config/*
837 quiet_cmd_gen_bbconfigopts = GEN include/bbconfigopts.h
838 cmd_gen_bbconfigopts = $(srctree)/scripts/mkconfigs > include/bbconfigopts.h
839 quiet_cmd_split_autoconf = SPLIT include/autoconf.h -> include/config/*
840 cmd_split_autoconf = scripts/basic/split-include include/autoconf.h include/config
841 #bbox# piggybacked generation of few .h files
842 include/config/MARKER: scripts/basic/split-include include/autoconf.h
843 $(call cmd,split_autoconf)
844 $(call cmd,gen_bbconfigopts)
847 # Generate some files
848 # ---------------------------------------------------------------------------
850 # KERNELRELEASE can change from a few different places, meaning version.h
851 # needs to be updated, so this check is forced on all builds
855 define filechk_version.h
856 if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
857 echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
860 (echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"; \
861 echo \#define LINUX_VERSION_CODE `expr $(VERSION) \\* 65536 + $(PATCHLEVEL) \\* 256 + $(SUBLEVEL)`; \
862 echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'; \
866 # ---------------------------------------------------------------------------
870 @echo '*** Warning: make $@ is unnecessary now.'
872 # ---------------------------------------------------------------------------
875 ifdef _BB_DISABLED_CONFIG_MODULES
877 # By default, build modules as well
884 modules: $(busybox-dirs) $(if $(KBUILD_BUILTIN),busybox)
885 @echo ' Building modules, stage 2.';
886 $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
889 # Target to prepare building external modules
890 PHONY += modules_prepare
891 modules_prepare: prepare scripts
893 # Target to install modules
894 PHONY += modules_install
895 modules_install: _modinst_ _modinst_post
899 @if [ -z "`$(DEPMOD) -V 2>/dev/null | grep module-init-tools`" ]; then \
900 echo "Warning: you may need to install module-init-tools"; \
901 echo "See http://www.codemonkey.org.uk/docs/post-halloween-2.6.txt";\
904 @rm -rf $(MODLIB)/kernel
905 @rm -f $(MODLIB)/source
906 @mkdir -p $(MODLIB)/kernel
907 @ln -s $(srctree) $(MODLIB)/source
908 @if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
909 rm -f $(MODLIB)/build ; \
910 ln -s $(objtree) $(MODLIB)/build ; \
912 $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modinst
914 # If System.map exists, run depmod. This deliberately does not have a
915 # dependency on System.map since that would run the dependency tree on
916 # busybox. This depmod is only for convenience to give the initial
917 # boot a modules.dep even before / is mounted read-write. However the
918 # boot script depmod is the master version.
919 ifeq "$(strip $(INSTALL_MOD_PATH))" ""
922 depmod_opts := -b $(INSTALL_MOD_PATH) -r
924 PHONY += _modinst_post
925 _modinst_post: _modinst_
926 if [ -r System.map -a -x $(DEPMOD) ]; then $(DEPMOD) -ae -F System.map $(depmod_opts) $(KERNELRELEASE); fi
928 else # CONFIG_MODULES
930 # Modules not configured
931 # ---------------------------------------------------------------------------
933 modules modules_install: FORCE
935 @echo "The present busybox configuration has modules disabled."
936 @echo "Type 'make config' and enable loadable module support."
937 @echo "Then build a kernel with module support enabled."
941 endif # CONFIG_MODULES
944 # Cleaning is done on three levels.
945 # make clean Delete most generated files
946 # Leave enough to build external modules
947 # make mrproper Delete the current configuration, and all generated files
948 # make distclean Remove editor backup files, patch leftover files and the like
950 # Directories & files removed with 'make clean'
951 CLEAN_DIRS += $(MODVERDIR) _install 0_lib
952 CLEAN_FILES += busybox busybox_unstripped* busybox.links \
953 System.map .kernelrelease \
954 .tmp_kallsyms* .tmp_version .tmp_busybox* .tmp_System.map
956 # Directories & files removed with 'make mrproper'
957 MRPROPER_DIRS += include/config include2
958 MRPROPER_FILES += .config .config.old include/asm .version .old_version \
960 include/bbconfigopts.h \
961 include/usage_compressed.h \
962 include/applet_tables.h \
964 .kernelrelease Module.symvers tags TAGS cscope* \
967 # clean - Delete most, but leave enough to build external modules
969 clean: rm-dirs := $(CLEAN_DIRS)
970 clean: rm-files := $(CLEAN_FILES)
971 clean-dirs := $(addprefix _clean_,$(srctree) $(busybox-alldirs))
973 PHONY += $(clean-dirs) clean archclean
975 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
977 clean: archclean $(clean-dirs)
980 @find . $(RCS_FIND_IGNORE) \
981 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
982 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \) \
983 -type f -print | xargs rm -f
986 doc-clean: rm-files := docs/busybox.pod \
987 docs/BusyBox.html docs/BusyBox.1 docs/BusyBox.txt
991 # mrproper - Delete all generated files, including .config
993 mrproper: rm-dirs := $(wildcard $(MRPROPER_DIRS))
994 mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
995 mrproper-dirs := $(addprefix _mrproper_,scripts)
997 PHONY += $(mrproper-dirs) mrproper archmrproper
999 $(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1001 mrproper: clean archmrproper $(mrproper-dirs)
1004 @find -name Config.src | sed 's/.src$/.in/' | xargs -r rm -f
1005 @find -name Kbuild.src | sed 's/.src$//' | xargs -r rm -f
1012 @find $(srctree) $(RCS_FIND_IGNORE) \
1013 \( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1014 -o -name '*.bak' -o -name '#*#' -o -name '.*.orig' \
1015 -o -name '.*.rej' -o -name '*.tmp' -o -size 0 \
1016 -o -name '*%' -o -name '.*.cmd' -o -name 'core' \) \
1017 -type f -print | xargs rm -f
1020 # Packaging of the kernel to various formats
1021 # ---------------------------------------------------------------------------
1022 # rpm target kept for backward compatibility
1023 package-dir := $(srctree)/scripts/package
1026 $(Q)$(MAKE) $(build)=$(package-dir) $@
1028 $(Q)$(MAKE) $(build)=$(package-dir) $@
1031 # Brief documentation of the typical targets used
1032 # ---------------------------------------------------------------------------
1034 boards := $(wildcard $(srctree)/arch/$(ARCH)/configs/*_defconfig)
1035 boards := $(notdir $(boards))
1037 -include $(srctree)/Makefile.help
1039 # Documentation targets
1040 # ---------------------------------------------------------------------------
1041 %docs: scripts_basic FORCE
1042 $(Q)$(MAKE) $(build)=Documentation/DocBook $@
1044 else # KBUILD_EXTMOD
1047 # External module support.
1048 # When building external modules the kernel used as basis is considered
1049 # read-only, and no consistency checks are made and the make
1050 # system is not used on the basis kernel. If updates are required
1051 # in the basis kernel ordinary make commands (without M=...) must
1054 # The following are the only valid targets when building external
1056 # make M=dir clean Delete all automatically generated files
1057 # make M=dir modules Make all modules in specified dir
1058 # make M=dir Same as 'make M=dir modules'
1059 # make M=dir modules_install
1060 # Install the modules build in the module directory
1061 # Assumes install directory is already created
1063 # We are always building modules
1065 PHONY += crmodverdir
1067 $(Q)mkdir -p $(MODVERDIR)
1068 $(Q)rm -f $(MODVERDIR)/*
1070 PHONY += $(objtree)/Module.symvers
1071 $(objtree)/Module.symvers:
1072 @test -e $(objtree)/Module.symvers || ( \
1074 echo " WARNING: Symbol version dump $(objtree)/Module.symvers"; \
1075 echo " is missing; modules will have no dependencies and modversions."; \
1078 module-dirs := $(addprefix _module_,$(KBUILD_EXTMOD))
1079 PHONY += $(module-dirs) modules
1080 $(module-dirs): crmodverdir $(objtree)/Module.symvers
1081 $(Q)$(MAKE) $(build)=$(patsubst _module_%,%,$@)
1083 modules: $(module-dirs)
1084 @echo ' Building modules, stage 2.';
1085 $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
1087 PHONY += modules_install
1088 modules_install: _emodinst_ _emodinst_post
1090 install-dir := $(if $(INSTALL_MOD_DIR),$(INSTALL_MOD_DIR),extra)
1093 $(Q)mkdir -p $(MODLIB)/$(install-dir)
1094 $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modinst
1096 # Run depmod only is we have System.map and depmod is executable
1097 quiet_cmd_depmod = DEPMOD $(KERNELRELEASE)
1098 cmd_depmod = if [ -r System.map -a -x $(DEPMOD) ]; then \
1099 $(DEPMOD) -ae -F System.map \
1100 $(if $(strip $(INSTALL_MOD_PATH)), \
1101 -b $(INSTALL_MOD_PATH) -r) \
1105 PHONY += _emodinst_post
1106 _emodinst_post: _emodinst_
1109 clean-dirs := $(addprefix _clean_,$(KBUILD_EXTMOD))
1111 PHONY += $(clean-dirs) clean
1113 $(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1115 clean: rm-dirs := $(MODVERDIR)
1116 clean: $(clean-dirs)
1118 @find $(KBUILD_EXTMOD) $(RCS_FIND_IGNORE) \
1119 \( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
1120 -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \) \
1121 -type f -print | xargs rm -f
1124 @echo ' Building external modules.'
1125 @echo ' Syntax: make -C path/to/kernel/src M=$$PWD target'
1127 @echo ' modules - default target, build the module(s)'
1128 @echo ' modules_install - install the module'
1129 @echo ' clean - remove generated files in module directory only'
1133 PHONY += prepare scripts
1136 endif # KBUILD_EXTMOD
1138 # Generate tags for editors
1139 # ---------------------------------------------------------------------------
1141 #We want __srctree to totally vanish out when KBUILD_OUTPUT is not set
1142 #(which is the most common case IMHO) to avoid unneeded clutter in the big tags file.
1143 #Adding $(srctree) adds about 20M on i386 to the size of the output file!
1145 ifeq ($(src),$(obj))
1148 __srctree = $(srctree)/
1151 ifeq ($(ALLSOURCE_ARCHS),)
1153 ALLINCLUDE_ARCHS := $(ARCH) $(SUBARCH)
1155 ALLINCLUDE_ARCHS := $(ARCH)
1158 #Allow user to specify only ALLSOURCE_PATHS on the command line, keeping existing behaviour.
1159 ALLINCLUDE_ARCHS := $(ALLSOURCE_ARCHS)
1162 ALLSOURCE_ARCHS := $(ARCH)
1165 ( find $(__srctree) $(RCS_FIND_IGNORE) \
1166 \( -name include -o -name arch \) -prune -o \
1167 -name '*.[chS]' -print; \
1168 for ARCH in $(ALLSOURCE_ARCHS) ; do \
1169 find $(__srctree)arch/$${ARCH} $(RCS_FIND_IGNORE) \
1170 -name '*.[chS]' -print; \
1172 find $(__srctree)security/selinux/include $(RCS_FIND_IGNORE) \
1173 -name '*.[chS]' -print; \
1174 find $(__srctree)include $(RCS_FIND_IGNORE) \
1175 \( -name config -o -name 'asm-*' \) -prune \
1176 -o -name '*.[chS]' -print; \
1177 for ARCH in $(ALLINCLUDE_ARCHS) ; do \
1178 find $(__srctree)include/asm-$${ARCH} $(RCS_FIND_IGNORE) \
1179 -name '*.[chS]' -print; \
1181 find $(__srctree)include/asm-generic $(RCS_FIND_IGNORE) \
1182 -name '*.[chS]' -print )
1185 quiet_cmd_cscope-file = FILELST cscope.files
1186 cmd_cscope-file = (echo \-k; echo \-q; $(all-sources)) > cscope.files
1188 quiet_cmd_cscope = MAKE cscope.out
1189 cmd_cscope = cscope -b
1192 $(call cmd,cscope-file)
1195 quiet_cmd_TAGS = MAKE $@
1198 ETAGSF=`etags --version | grep -i exuberant >/dev/null && \
1199 echo "-I __initdata,__exitdata,__acquires,__releases \
1200 -I EXPORT_SYMBOL,EXPORT_SYMBOL_GPL \
1201 --extra=+f --c-kinds=+px"`; \
1202 $(all-sources) | xargs etags $$ETAGSF -a
1209 quiet_cmd_tags = MAKE $@
1212 CTAGSF=`ctags --version | grep -i exuberant >/dev/null && \
1213 echo "-I __initdata,__exitdata,__acquires,__releases \
1214 -I EXPORT_SYMBOL,EXPORT_SYMBOL_GPL \
1215 --extra=+f --c-kinds=+px"`; \
1216 $(all-sources) | xargs ctags $$CTAGSF -a
1223 # Scripts to check various things for consistency
1224 # ---------------------------------------------------------------------------
1227 find * $(RCS_FIND_IGNORE) \
1228 -name '*.[hcS]' -type f -print | sort \
1229 | xargs $(PERL) -w scripts/checkincludes.pl
1232 find * $(RCS_FIND_IGNORE) \
1233 -name '*.[hcS]' -type f -print | sort \
1234 | xargs $(PERL) -w scripts/checkversion.pl
1237 $(PERL) $(srctree)/scripts/namespace.pl
1239 endif #ifeq ($(config-targets),1)
1240 endif #ifeq ($(mixed-targets),1)
1244 $(OBJDUMP) -d busybox $$(find . -name '*.ko') | \
1245 $(PERL) $(src)/scripts/checkstack.pl $(ARCH)
1248 $(if $(wildcard .kernelrelease), $(Q)echo $(KERNELRELEASE), \
1249 $(error kernelrelease not valid - run 'make *config' to update it))
1251 @echo $(KERNELVERSION)
1254 # ---------------------------------------------------------------------------
1255 # Single targets are compatible with:
1256 # - build whith mixed source and output
1257 # - build with separate output dir 'make O=...'
1258 # - external modules
1260 # target-dir => where to store outputfile
1261 # build-dir => directory in kernel source tree to use
1263 ifeq ($(KBUILD_EXTMOD),)
1264 build-dir = $(patsubst %/,%,$(dir $@))
1265 target-dir = $(dir $@)
1267 zap-slash=$(filter-out .,$(patsubst %/,%,$(dir $@)))
1268 build-dir = $(KBUILD_EXTMOD)$(if $(zap-slash),/$(zap-slash))
1269 target-dir = $(if $(KBUILD_EXTMOD),$(dir $<),$(dir $@))
1272 %.s: %.c prepare scripts FORCE
1273 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1274 %.i: %.c prepare scripts FORCE
1275 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1276 %.o: %.c prepare scripts FORCE
1277 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1278 %.lst: %.c prepare scripts FORCE
1279 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1280 %.s: %.S prepare scripts FORCE
1281 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1282 %.o: %.S prepare scripts FORCE
1283 $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@)
1286 / %/: prepare scripts FORCE
1287 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1288 $(build)=$(build-dir)
1289 %.ko: prepare scripts FORCE
1290 $(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
1291 $(build)=$(build-dir) $(@:.ko=.o)
1292 $(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
1294 # FIXME Should go into a make.lib or something
1295 # ===========================================================================
1297 quiet_cmd_rmdirs = $(if $(wildcard $(rm-dirs)),CLEAN $(wildcard $(rm-dirs)))
1298 cmd_rmdirs = rm -rf $(rm-dirs)
1300 quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files)))
1301 cmd_rmfiles = rm -f $(rm-files)
1304 a_flags = -Wp,-MD,$(depfile) $(AFLAGS) $(AFLAGS_KERNEL) \
1305 $(NOSTDINC_FLAGS) $(CPPFLAGS) \
1306 $(modkern_aflags) $(EXTRA_AFLAGS) $(AFLAGS_$(*F).o)
1308 quiet_cmd_as_o_S = AS $@
1309 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
1311 # read all saved command lines
1313 targets := $(wildcard $(sort $(targets)))
1314 cmd_files := $(wildcard .*.cmd $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
1316 ifneq ($(cmd_files),)
1317 $(cmd_files): ; # Do not try to update included dependency files
1318 include $(cmd_files)
1321 # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=dir
1323 # $(Q)$(MAKE) $(clean)=dir
1324 clean := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.clean obj
1326 endif # skip-makefile
1331 -include $(srctree)/Makefile.custom
1333 # Declare the contents of the .PHONY variable as phony. We keep that
1334 # information in a variable se we can use it in if_changed and friends.