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Makefile
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VERSION = 1
PATCHLEVEL = 26
SUBLEVEL = 2
EXTRAVERSION =
NAME = Unnamed
# *DOCUMENTATION*
# To see a list of typical targets execute "make help"
# More info can be located in ./README
# Comments in this file are targeted only to the developer, do not
# expect to learn how to build the kernel reading this file.
# Do not print "Entering directory ..."
MAKEFLAGS += --no-print-directory
# We are using a recursive build, so we need to do a little thinking
# to get the ordering right.
#
# Most importantly: sub-Makefiles should only ever modify files in
# their own directory. If in some directory we have a dependency on
# a file in another dir (which doesn't happen often, but it's often
# unavoidable when linking the built-in.o targets which finally
# turn into busybox), we will call a sub make in that other dir, and
# after that we are sure that everything which is in that other dir
# is now up to date.
#
# The only cases where we need to modify files which have global
# effects are thus separated out and done before the recursive
# descending is started. They are now explicitly listed as the
# prepare rule.
# To put more focus on warnings, be less verbose as default
# Use 'make V=1' to see the full commands
ifdef V
ifeq ("$(origin V)", "command line")
KBUILD_VERBOSE = $(V)
endif
endif
ifndef KBUILD_VERBOSE
KBUILD_VERBOSE = 0
endif
# Call sparse as part of compilation of C files
# Use 'make C=1' to enable sparse checking
ifdef C
ifeq ("$(origin C)", "command line")
KBUILD_CHECKSRC = $(C)
endif
endif
ifndef KBUILD_CHECKSRC
KBUILD_CHECKSRC = 0
endif
# Use make M=dir to specify directory of external module to build
# Old syntax make ... SUBDIRS=$PWD is still supported
# Setting the environment variable KBUILD_EXTMOD take precedence
ifdef SUBDIRS
KBUILD_EXTMOD ?= $(SUBDIRS)
endif
ifdef M
ifeq ("$(origin M)", "command line")
KBUILD_EXTMOD := $(M)
endif
endif
# kbuild supports saving output files in a separate directory.
# To locate output files in a separate directory two syntaxes are supported.
# In both cases the working directory must be the root of the kernel src.
# 1) O=
# Use "make O=dir/to/store/output/files/"
#
# 2) Set KBUILD_OUTPUT
# Set the environment variable KBUILD_OUTPUT to point to the directory
# where the output files shall be placed.
# export KBUILD_OUTPUT=dir/to/store/output/files/
# make
#
# The O= assignment takes precedence over the KBUILD_OUTPUT environment
# variable.
# KBUILD_SRC is set on invocation of make in OBJ directory
# KBUILD_SRC is not intended to be used by the regular user (for now)
ifeq ($(KBUILD_SRC),)
# OK, Make called in directory where kernel src resides
# Do we want to locate output files in a separate directory?
ifdef O
ifeq ("$(origin O)", "command line")
KBUILD_OUTPUT := $(O)
endif
endif
# That's our default target when none is given on the command line
PHONY := _all
_all:
ifneq ($(KBUILD_OUTPUT),)
# Invoke a second make in the output directory, passing relevant variables
# check that the output directory actually exists
saved-output := $(KBUILD_OUTPUT)
KBUILD_OUTPUT := $(shell cd $(KBUILD_OUTPUT) && /bin/pwd)
$(if $(KBUILD_OUTPUT),, \
$(error output directory "$(saved-output)" does not exist))
PHONY += $(MAKECMDGOALS)
$(filter-out _all,$(MAKECMDGOALS)) _all:
$(if $(KBUILD_VERBOSE:1=),@)$(MAKE) -C $(KBUILD_OUTPUT) \
KBUILD_SRC=$(CURDIR) \
KBUILD_EXTMOD="$(KBUILD_EXTMOD)" -f $(CURDIR)/Makefile $@
# Leave processing to above invocation of make
skip-makefile := 1
endif # ifneq ($(KBUILD_OUTPUT),)
endif # ifeq ($(KBUILD_SRC),)
# We process the rest of the Makefile if this is the final invocation of make
ifeq ($(skip-makefile),)
# If building an external module we do not care about the all: rule
# but instead _all depend on modules
PHONY += all
ifeq ($(KBUILD_EXTMOD),)
_all: all
else
_all: modules
endif
srctree := $(if $(KBUILD_SRC),$(KBUILD_SRC),$(CURDIR))
TOPDIR := $(srctree)
# FIXME - TOPDIR is obsolete, use srctree/objtree
objtree := $(CURDIR)
src := $(srctree)
obj := $(objtree)
VPATH := $(srctree)$(if $(KBUILD_EXTMOD),:$(KBUILD_EXTMOD))
export srctree objtree VPATH TOPDIR
# Cross compiling and selecting different set of gcc/bin-utils
# ---------------------------------------------------------------------------
#
# When performing cross compilation for other architectures ARCH shall be set
# to the target architecture. (See arch/* for the possibilities).
# ARCH can be set during invocation of make:
# make ARCH=ia64
# Another way is to have ARCH set in the environment.
# The default ARCH is the host where make is executed.
# CROSS_COMPILE specify the prefix used for all executables used
# during compilation. Only gcc and related bin-utils executables
# are prefixed with $(CROSS_COMPILE).
# CROSS_COMPILE can be set on the command line
# make CROSS_COMPILE=ia64-linux-
# Alternatively CROSS_COMPILE can be set in the environment.
# Default value for CROSS_COMPILE is not to prefix executables
# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
CROSS_COMPILE ?=
# bbox: we may have CONFIG_CROSS_COMPILER_PREFIX in .config,
# and it has not been included yet... thus using an awkward syntax.
ifeq ($(CROSS_COMPILE),)
CROSS_COMPILE := $(shell grep ^CONFIG_CROSS_COMPILER_PREFIX .config 2>/dev/null)
CROSS_COMPILE := $(subst CONFIG_CROSS_COMPILER_PREFIX=,,$(CROSS_COMPILE))
CROSS_COMPILE := $(subst ",,$(CROSS_COMPILE))
#")
endif
# SUBARCH tells the usermode build what the underlying arch is. That is set
# first, and if a usermode build is happening, the "ARCH=um" on the command
# line overrides the setting of ARCH below. If a native build is happening,
# then ARCH is assigned, getting whatever value it gets normally, and
# SUBARCH is subsequently ignored.
ifneq ($(CROSS_COMPILE),)
SUBARCH := $(shell echo $(CROSS_COMPILE) | cut -d- -f1)
else
SUBARCH := $(shell uname -m)
endif
SUBARCH := $(shell echo $(SUBARCH) | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
-e s/arm.*/arm/ -e s/sa110/arm/ \
-e s/s390x/s390/ -e s/parisc64/parisc/ \
-e s/ppc.*/powerpc/ -e s/mips.*/mips/ )
ARCH ?= $(SUBARCH)
# Architecture as present in compile.h
UTS_MACHINE := $(ARCH)
# SHELL used by kbuild
CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
else if [ -x /bin/bash ]; then echo /bin/bash; \
else echo sh; fi ; fi)
# Decide whether to build built-in, modular, or both.
# Normally, just do built-in.
KBUILD_MODULES :=
KBUILD_BUILTIN := 1
# If we have only "make modules", don't compile built-in objects.
# When we're building modules with modversions, we need to consider
# the built-in objects during the descend as well, in order to
# make sure the checksums are uptodate before we record them.
ifeq ($(MAKECMDGOALS),modules)
KBUILD_BUILTIN := $(if $(CONFIG_MODVERSIONS),1)
endif
# If we have "make <whatever> modules", compile modules
# in addition to whatever we do anyway.
# Just "make" or "make all" shall build modules as well
ifneq ($(filter all _all modules,$(MAKECMDGOALS)),)
KBUILD_MODULES := 1
endif
ifeq ($(MAKECMDGOALS),)
KBUILD_MODULES := 1
endif
export KBUILD_MODULES KBUILD_BUILTIN
export KBUILD_CHECKSRC KBUILD_SRC KBUILD_EXTMOD
# Beautify output
# ---------------------------------------------------------------------------
#
# Normally, we echo the whole command before executing it. By making
# that echo $($(quiet)$(cmd)), we now have the possibility to set
# $(quiet) to choose other forms of output instead, e.g.
#
# quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
# cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
#
# If $(quiet) is empty, the whole command will be printed.
# If it is set to "quiet_", only the short version will be printed.
# If it is set to "silent_", nothing wil be printed at all, since
# the variable $(silent_cmd_cc_o_c) doesn't exist.
#
# A simple variant is to prefix commands with $(Q) - that's useful
# for commands that shall be hidden in non-verbose mode.
#
# $(Q)ln $@ :<
#
# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
# If KBUILD_VERBOSE equals 1 then the above command is displayed.
ifeq ($(KBUILD_VERBOSE),1)
quiet =
Q =
else
quiet=quiet_
Q = @
endif
# If the user is running make -s (silent mode), suppress echoing of
# commands
ifneq ($(findstring s,$(MAKEFLAGS)),)
quiet=silent_
endif
export quiet Q KBUILD_VERBOSE
# Look for make include files relative to root of kernel src
MAKEFLAGS += --include-dir=$(srctree)
HOSTCC = gcc
HOSTCXX = g++
HOSTCFLAGS :=
HOSTCXXFLAGS :=
# We need some generic definitions
include $(srctree)/scripts/Kbuild.include
HOSTCFLAGS += $(call hostcc-option,-Wall -Wstrict-prototypes -O2 -fomit-frame-pointer,)
HOSTCXXFLAGS += -O2
# For maximum performance (+ possibly random breakage, uncomment
# the following)
MAKEFLAGS += -rR
# Make variables (CC, etc...)
AS = $(CROSS_COMPILE)as
CC = $(CROSS_COMPILE)gcc
LD = $(CC) -nostdlib
CPP = $(CC) -E
AR = $(CROSS_COMPILE)ar
NM = $(CROSS_COMPILE)nm
STRIP = $(CROSS_COMPILE)strip
OBJCOPY = $(CROSS_COMPILE)objcopy
OBJDUMP = $(CROSS_COMPILE)objdump
PKG_CONFIG ?= $(CROSS_COMPILE)pkg-config
AWK = awk
GENKSYMS = scripts/genksyms/genksyms
DEPMOD = /sbin/depmod
KALLSYMS = scripts/kallsyms
PERL = perl
CHECK = sparse
CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ -Wbitwise $(CF)
MODFLAGS = -DMODULE
CFLAGS_MODULE = $(MODFLAGS)
AFLAGS_MODULE = $(MODFLAGS)
LDFLAGS_MODULE = -r
CFLAGS_KERNEL =
AFLAGS_KERNEL =
# Use LINUXINCLUDE when you must reference the include/ directory.
# Needed to be compatible with the O= option
CFLAGS := $(CFLAGS)
# Added only to final link stage of busybox binary
CFLAGS_busybox := $(CFLAGS_busybox)
CPPFLAGS := $(CPPFLAGS)
AFLAGS := $(AFLAGS)
LDFLAGS := $(LDFLAGS)
LDLIBS :=
# Read KERNELRELEASE from .kernelrelease (if it exists)
KERNELRELEASE = $(shell cat .kernelrelease 2> /dev/null)
KERNELVERSION = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)
export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION \
ARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC \
CPP AR NM STRIP OBJCOPY OBJDUMP MAKE AWK GENKSYMS PERL UTS_MACHINE \
HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
export CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
export CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
export AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
export FLTFLAGS
# When compiling out-of-tree modules, put MODVERDIR in the module
# tree rather than in the kernel tree. The kernel tree might
# even be read-only.
export MODVERDIR := $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_versions
# Files to ignore in find ... statements
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
export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn --exclude CVS --exclude .pc --exclude .hg --exclude .git
# ===========================================================================
# Rules shared between *config targets and build targets
# Basic helpers built in scripts/
PHONY += scripts_basic
scripts_basic:
$(Q)$(MAKE) $(build)=scripts/basic
# To avoid any implicit rule to kick in, define an empty command.
scripts/basic/%: scripts_basic ;
# This target generates Kbuild's and Config.in's from *.c files
PHONY += gen_build_files
gen_build_files: $(wildcard $(srctree)/*/*.c) $(wildcard $(srctree)/*/*/*.c)
$(Q)$(srctree)/scripts/gen_build_files.sh $(srctree) $(objtree)
# bbox: we have helpers in applets/
# we depend on scripts_basic, since scripts/basic/fixdep
# must be built before any other host prog
PHONY += applets_dir
applets_dir: scripts_basic gen_build_files
$(Q)$(MAKE) $(build)=applets
applets/%: applets_dir ;
PHONY += outputmakefile
# outputmakefile generates a Makefile in the output directory, if using a
# separate output directory. This allows convenient use of make in the
# output directory.
outputmakefile:
ifneq ($(KBUILD_SRC),)
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
$(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
endif
# To make sure we do not include .config for any of the *config targets
# catch them early, and hand them over to scripts/kconfig/Makefile
# It is allowed to specify more targets when calling make, including
# mixing *config targets and build targets.
# For example 'make oldconfig all'.
# Detect when mixed targets is specified, and make a second invocation
# of make so .config is not included in this case either (for *config).
no-dot-config-targets := clean mrproper distclean \
cscope TAGS tags help %docs
#bbox# check% is removed from above
config-targets := 0
mixed-targets := 0
dot-config := 1
ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
dot-config := 0
endif
endif
ifeq ($(KBUILD_EXTMOD),)
ifneq ($(filter config %config,$(MAKECMDGOALS)),)
config-targets := 1
ifneq ($(filter-out config %config,$(MAKECMDGOALS)),)
mixed-targets := 1
endif
endif
endif
ifeq ($(mixed-targets),1)
# ===========================================================================
# We're called with mixed targets (*config and build targets).
# Handle them one by one.
%:: FORCE
$(Q)$(MAKE) -C $(srctree) KBUILD_SRC= $@
else
ifeq ($(config-targets),1)
# ===========================================================================
# *config targets only - make sure prerequisites are updated, and descend
# in scripts/kconfig to make the *config target
# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
# KBUILD_DEFCONFIG may point out an alternative default configuration
# used for 'make defconfig'
-include $(srctree)/arch/$(ARCH)/Makefile
export KBUILD_DEFCONFIG
config: scripts_basic outputmakefile gen_build_files FORCE
$(Q)mkdir -p include
$(Q)$(MAKE) $(build)=scripts/kconfig $@
$(Q)$(MAKE) -C $(srctree) KBUILD_SRC= .kernelrelease
%config: scripts_basic outputmakefile gen_build_files FORCE
$(Q)mkdir -p include
$(Q)$(MAKE) $(build)=scripts/kconfig $@
$(Q)$(MAKE) -C $(srctree) KBUILD_SRC= .kernelrelease
else
# ===========================================================================
# Build targets only - this includes busybox, arch specific targets, clean
# targets and others. In general all targets except *config targets.
ifeq ($(KBUILD_EXTMOD),)
# Additional helpers built in scripts/
# Carefully list dependencies so we do not try to build scripts twice
# in parallel
PHONY += scripts
scripts: gen_build_files scripts_basic include/config/MARKER
$(Q)$(MAKE) $(build)=$(@)
scripts_basic: include/autoconf.h
# Objects we will link into busybox / subdirs we need to visit
core-y := \
applets/ \
libs-y := \
archival/ \
archival/libarchive/ \
console-tools/ \
coreutils/ \
coreutils/libcoreutils/ \
debianutils/ \
e2fsprogs/ \
editors/ \
eperd/ \
findutils/ \
init/ \
libbb/ \
libpwdgrp/ \
loginutils/ \
mailutils/ \
miscutils/ \
modutils/ \
networking/ \
networking/libiproute/ \
networking/udhcp/ \
printutils/ \
procps/ \
runit/ \
selinux/ \
shell/ \
sysklogd/ \
util-linux/ \
util-linux/volume_id/ \
libs-y := \
archival/ \
archival/libarchive/ \
coreutils/ \
eperd/ \
libbb/ \
libpwdgrp/ \
miscutils/ \
networking/ \
endif # KBUILD_EXTMOD
ifeq ($(dot-config),1)
# In this section, we need .config
# Read in dependencies to all Kconfig* files, make sure to run
# oldconfig if changes are detected.
-include .kconfig.d
-include .config
# If .config needs to be updated, it will be done via the dependency
# that autoconf has on .config.
# To avoid any implicit rule to kick in, define an empty command
.config .kconfig.d: ;
# Now we can define CFLAGS etc according to .config
include $(srctree)/Makefile.flags
# If .config is newer than include/autoconf.h, someone tinkered
# with it and forgot to run make oldconfig.
# If kconfig.d is missing then we are probarly in a cleaned tree so
# we execute the config step to be sure to catch updated Kconfig files
include/autoconf.h: .kconfig.d .config $(wildcard $(srctree)/*/*.c) $(wildcard $(srctree)/*/*/*.c) | gen_build_files
$(Q)$(MAKE) -f $(srctree)/Makefile silentoldconfig
include/usage.h: gen_build_files
else
# Dummy target needed, because used as prerequisite
include/autoconf.h: ;
endif
# The all: target is the default when no target is given on the
# command line.
# This allow a user to issue only 'make' to build a kernel including modules
# Defaults busybox but it is usually overridden in the arch makefile
all: busybox # doc
-include $(srctree)/arch/$(ARCH)/Makefile
# arch Makefile may override CC so keep this after arch Makefile is included
#bbox# NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
CHECKFLAGS += $(NOSTDINC_FLAGS)
# Default kernel image to build when no specific target is given.
# KBUILD_IMAGE may be overruled on the commandline or
# set in the environment
# Also any assignments in arch/$(ARCH)/Makefile take precedence over
# this default value
export KBUILD_IMAGE ?= busybox
#
# INSTALL_PATH specifies where to place the updated kernel and system map
# images. Default is /boot, but you can set it to other values
export INSTALL_PATH ?= /boot
#
# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
# relocations required by build roots. This is not defined in the
# makefile but the argument can be passed to make if needed.
#
MODLIB = $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
export MODLIB
ifeq ($(KBUILD_EXTMOD),)
busybox-dirs := $(patsubst %/,%,$(filter %/, $(core-y) $(core-m) $(libs-y) $(libs-m)))
busybox-alldirs := $(sort $(busybox-dirs) $(patsubst %/,%,$(filter %/, \
$(core-n) $(core-) $(libs-n) $(libs-) \
)))
core-y := $(patsubst %/, %/built-in.o, $(core-y))
libs-y1 := $(patsubst %/, %/lib.a, $(libs-y))
libs-y2 := $(patsubst %/, %/built-in.o, $(libs-y))
libs-y := $(libs-y1) $(libs-y2)
# Build busybox
# ---------------------------------------------------------------------------
# busybox is build from the objects selected by $(busybox-init) and
# $(busybox-main). Most are built-in.o files from top-level directories
# in the kernel tree, others are specified in arch/$(ARCH)Makefile.
# Ordering when linking is important, and $(busybox-init) must be first.
#
# busybox
# ^
# |
# +-< $(busybox-init)
# | +--< init/version.o + more
# |
# +--< $(busybox-main)
# | +--< driver/built-in.o mm/built-in.o + more
# |
# +-< kallsyms.o (see description in CONFIG_KALLSYMS section)
#
# busybox version (uname -v) cannot be updated during normal
# descending-into-subdirs phase since we do not yet know if we need to
# update busybox.
# Therefore this step is delayed until just before final link of busybox -
# except in the kallsyms case where it is done just before adding the
# symbols to the kernel.
#
# System.map is generated to document addresses of all kernel symbols
busybox-all := $(core-y) $(libs-y)
# Rule to link busybox - also used during CONFIG_KALLSYMS
# May be overridden by arch/$(ARCH)/Makefile
quiet_cmd_busybox__ ?= LINK $@
cmd_busybox__ ?= $(srctree)/scripts/trylink \
"$@" \
"$(CC)" \
"$(CFLAGS) $(CFLAGS_busybox)" \
"$(LDFLAGS) $(EXTRA_LDFLAGS)" \
"$(core-y)" \
"$(libs-y)" \
"$(LDLIBS)" \
&& $(srctree)/scripts/generate_BUFSIZ.sh --post include/common_bufsiz.h
# Generate System.map
quiet_cmd_sysmap = SYSMAP
cmd_sysmap = $(CONFIG_SHELL) $(srctree)/scripts/mksysmap
# Link of busybox
# If CONFIG_KALLSYMS is set .version is already updated
# Generate System.map and verify that the content is consistent
# Use + in front of the busybox_version rule to silent warning with make -j2
# First command is ':' to allow us to use + in front of the rule
define rule_busybox__
:
$(call cmd,busybox__)
$(Q)echo 'cmd_$@ := $(cmd_busybox__)' > $(@D)/.$(@F).cmd
endef
ifdef CONFIG_KALLSYMS
# Generate section listing all symbols and add it into busybox $(kallsyms.o)
# It's a three stage process:
# o .tmp_busybox1 has all symbols and sections, but __kallsyms is
# empty
# Running kallsyms on that gives us .tmp_kallsyms1.o with
# the right size - busybox version (uname -v) is updated during this step
# o .tmp_busybox2 now has a __kallsyms section of the right size,
# but due to the added section, some addresses have shifted.
# From here, we generate a correct .tmp_kallsyms2.o
# o The correct .tmp_kallsyms2.o is linked into the final busybox.
# o Verify that the System.map from busybox matches the map from
# .tmp_busybox2, just in case we did not generate kallsyms correctly.
# o If CONFIG_KALLSYMS_EXTRA_PASS is set, do an extra pass using
# .tmp_busybox3 and .tmp_kallsyms3.o. This is only meant as a
# temporary bypass to allow the kernel to be built while the
# maintainers work out what went wrong with kallsyms.
ifdef CONFIG_KALLSYMS_EXTRA_PASS
last_kallsyms := 3
else
last_kallsyms := 2
endif
kallsyms.o := .tmp_kallsyms$(last_kallsyms).o
define verify_kallsyms
$(Q)$(if $($(quiet)cmd_sysmap), \
echo ' $($(quiet)cmd_sysmap) .tmp_System.map' &&) \
$(cmd_sysmap) .tmp_busybox$(last_kallsyms) .tmp_System.map
$(Q)cmp -s System.map .tmp_System.map || \
(echo Inconsistent kallsyms data; \
echo Try setting CONFIG_KALLSYMS_EXTRA_PASS; \
rm .tmp_kallsyms* ; /bin/false )
endef
# Update busybox version before link
# Use + in front of this rule to silent warning about make -j1
# First command is ':' to allow us to use + in front of this rule
cmd_ksym_ld = $(cmd_busybox__)
define rule_ksym_ld
:
+$(call cmd,busybox_version)
$(call cmd,busybox__)
$(Q)echo 'cmd_$@ := $(cmd_busybox__)' > $(@D)/.$(@F).cmd
endef
# Generate .S file with all kernel symbols
quiet_cmd_kallsyms = KSYM $@
cmd_kallsyms = $(NM) -n $< | $(KALLSYMS) \
$(if $(CONFIG_KALLSYMS_ALL),--all-symbols) > $@
.tmp_kallsyms1.o .tmp_kallsyms2.o .tmp_kallsyms3.o: %.o: %.S scripts FORCE
$(call if_changed_dep,as_o_S)
.tmp_kallsyms%.S: .tmp_busybox% $(KALLSYMS)
$(call cmd,kallsyms)
# .tmp_busybox1 must be complete except kallsyms, so update busybox version
.tmp_busybox1: $(busybox-lds) $(busybox-all) FORCE
$(call if_changed_rule,ksym_ld)
.tmp_busybox2: $(busybox-lds) $(busybox-all) .tmp_kallsyms1.o FORCE
$(call if_changed,busybox__)
.tmp_busybox3: $(busybox-lds) $(busybox-all) .tmp_kallsyms2.o FORCE
$(call if_changed,busybox__)
# Needs to visit scripts/ before $(KALLSYMS) can be used.
$(KALLSYMS): scripts ;
# Generate some data for debugging strange kallsyms problems
debug_kallsyms: .tmp_map$(last_kallsyms)
.tmp_map%: .tmp_busybox% FORCE
($(OBJDUMP) -h $< | $(AWK) '/^ +[0-9]/{print $$4 " 0 " $$2}'; $(NM) $<) | sort > $@
.tmp_map3: .tmp_map2
.tmp_map2: .tmp_map1
endif # ifdef CONFIG_KALLSYMS
# busybox image - including updated kernel symbols
busybox_unstripped: $(busybox-all) FORCE
$(call if_changed_rule,busybox__)
$(Q)rm -f .old_version
busybox: busybox_unstripped
ifeq ($(SKIP_STRIP),y)
$(Q)cp $< $@
else
$(Q)$(STRIP) -s --remove-section=.note --remove-section=.comment \
busybox_unstripped -o $@
# strip is confused by PIE executable and does not set exec bits
$(Q)chmod a+x $@
endif
# The actual objects are generated when descending,
# make sure no implicit rule kicks in
$(sort $(busybox-all)): $(busybox-dirs) ;
# Handle descending into subdirectories listed in $(busybox-dirs)
# Preset locale variables to speed up the build process. Limit locale
# tweaks to this spot to avoid wrong language settings when running
# make menuconfig etc.
# Error messages still appears in the original language
PHONY += $(busybox-dirs)
$(busybox-dirs): prepare scripts
$(Q)$(MAKE) $(build)=$@
# Build the kernel release string
# The KERNELRELEASE is stored in a file named .kernelrelease
# to be used when executing for example make install or make modules_install
#
# Take the contents of any files called localversion* and the config
# variable CONFIG_LOCALVERSION and append them to KERNELRELEASE.
# LOCALVERSION from the command line override all of this
nullstring :=
space := $(nullstring) # end of line
___localver = $(objtree)/localversion* $(srctree)/localversion*
__localver = $(sort $(wildcard $(___localver)))
# skip backup files (containing '~')
_localver = $(foreach f, $(__localver), $(if $(findstring ~, $(f)),,$(f)))
localver = $(subst $(space),, \
$(shell cat /dev/null $(_localver)) \
$(patsubst "%",%,$(CONFIG_LOCALVERSION)))
# If CONFIG_LOCALVERSION_AUTO is set scripts/setlocalversion is called
# and if the SCM is know a tag from the SCM is appended.
# The appended tag is determinded by the SCM used.
#
# Currently, only git is supported.
# Other SCMs can edit scripts/setlocalversion and add the appropriate
# checks as needed.
ifdef _BB_DISABLED_CONFIG_LOCALVERSION_AUTO
_localver-auto = $(shell $(CONFIG_SHELL) \
$(srctree)/scripts/setlocalversion $(srctree))
localver-auto = $(LOCALVERSION)$(_localver-auto)
endif
localver-full = $(localver)$(localver-auto)
# Store (new) KERNELRELASE string in .kernelrelease
kernelrelease = $(KERNELVERSION)$(localver-full)
.kernelrelease: FORCE
$(Q)rm -f $@
$(Q)echo $(kernelrelease) > $@
# Things we need to do before we recursively start building the kernel
# or the modules are listed in "prepare".
# A multi level approach is used. prepareN is processed before prepareN-1.
# archprepare is used in arch Makefiles and when processed asm symlink,
# version.h and scripts_basic is processed / created.
# Listed in dependency order
PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3
# prepare-all is deprecated, use prepare as valid replacement
PHONY += prepare-all
# prepare3 is used to check if we are building in a separate output directory,
# and if so do:
# 1) Check that make has not been executed in the kernel src $(srctree)
# 2) Create the include2 directory, used for the second asm symlink
prepare3: .kernelrelease
ifneq ($(KBUILD_SRC),)
@echo ' Using $(srctree) as source for busybox'
$(Q)if [ -f $(srctree)/.config ]; then \
echo " $(srctree) is not clean, please run 'make mrproper'";\
echo " in the '$(srctree)' directory.";\
/bin/false; \
fi;
$(Q)if [ ! -d include2 ]; then mkdir -p include2; fi;
$(Q)ln -fsn $(srctree)/include/asm-$(ARCH) include2/asm
endif
# prepare2 creates a makefile if using a separate output directory
prepare2: prepare3 outputmakefile
prepare1: prepare2 include/config/MARKER
ifneq ($(KBUILD_MODULES),)
$(Q)mkdir -p $(MODVERDIR)
$(Q)rm -f $(MODVERDIR)/*
endif
archprepare: prepare1 scripts_basic applets_dir
prepare0: archprepare FORCE
$(Q)$(MAKE) $(build)=.
# All the preparing..
prepare prepare-all: prepare0
# Leave this as default for preprocessing busybox.lds.S, which is now
# done in arch/$(ARCH)/kernel/Makefile
export CPPFLAGS_busybox.lds += -P -C -U$(ARCH)
# FIXME: The asm symlink changes when $(ARCH) changes. That's
# hard to detect, but I suppose "make mrproper" is a good idea
# before switching between archs anyway.
#bbox# include/asm:
#bbox# @echo ' SYMLINK $@ -> include/asm-$(ARCH)'
#bbox# $(Q)if [ ! -d include ]; then mkdir -p include; fi;
#bbox# @ln -fsn asm-$(ARCH) $@
# Split autoconf.h into include/linux/config/*
quiet_cmd_gen_bbconfigopts = GEN include/bbconfigopts.h
cmd_gen_bbconfigopts = $(srctree)/scripts/mkconfigs include/bbconfigopts.h include/bbconfigopts_bz2.h
quiet_cmd_gen_common_bufsiz = GEN include/common_bufsiz.h
cmd_gen_common_bufsiz = $(srctree)/scripts/generate_BUFSIZ.sh include/common_bufsiz.h
quiet_cmd_split_autoconf = SPLIT include/autoconf.h -> include/config/*
cmd_split_autoconf = scripts/basic/split-include include/autoconf.h include/config
#bbox# piggybacked generation of few .h files
include/config/MARKER: scripts/basic/split-include include/autoconf.h
$(call cmd,split_autoconf)
$(call cmd,gen_bbconfigopts)
$(call cmd,gen_common_bufsiz)
@touch $@
# Generate some files
# ---------------------------------------------------------------------------
# KERNELRELEASE can change from a few different places, meaning version.h
# needs to be updated, so this check is forced on all builds
uts_len := 64
define filechk_version.h
if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2; \
exit 1; \
fi; \
(echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"; \
echo \#define LINUX_VERSION_CODE `expr $(VERSION) \\* 65536 + $(PATCHLEVEL) \\* 256 + $(SUBLEVEL)`; \
echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))'; \
)
endef
# ---------------------------------------------------------------------------
PHONY += depend dep
depend dep:
@echo '*** Warning: make $@ is unnecessary now.'
# ---------------------------------------------------------------------------
# Modules
ifdef _BB_DISABLED_CONFIG_MODULES
# By default, build modules as well
all: modules
# Build modules
PHONY += modules
modules: $(busybox-dirs) $(if $(KBUILD_BUILTIN),busybox)
@echo ' Building modules, stage 2.';
$(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modpost
# Target to prepare building external modules
PHONY += modules_prepare
modules_prepare: prepare scripts
# Target to install modules
PHONY += modules_install
modules_install: _modinst_ _modinst_post
PHONY += _modinst_
_modinst_:
@if [ -z "`$(DEPMOD) -V 2>/dev/null | grep module-init-tools`" ]; then \
echo "Warning: you may need to install module-init-tools"; \
echo "See http://www.codemonkey.org.uk/docs/post-halloween-2.6.txt";\
sleep 1; \
fi
@rm -rf $(MODLIB)/kernel
@rm -f $(MODLIB)/source
@mkdir -p $(MODLIB)/kernel
@ln -s $(srctree) $(MODLIB)/source
@if [ ! $(objtree) -ef $(MODLIB)/build ]; then \
rm -f $(MODLIB)/build ; \
ln -s $(objtree) $(MODLIB)/build ; \
fi
$(Q)$(MAKE) -rR -f $(srctree)/scripts/Makefile.modinst
# If System.map exists, run depmod. This deliberately does not have a
# dependency on System.map since that would run the dependency tree on
# busybox. This depmod is only for convenience to give the initial
# boot a modules.dep even before / is mounted read-write. However the
# boot script depmod is the master version.
ifeq "$(strip $(INSTALL_MOD_PATH))" ""
depmod_opts :=
else
depmod_opts := -b $(INSTALL_MOD_PATH) -r
endif
PHONY += _modinst_post
_modinst_post: _modinst_
if [ -r System.map -a -x $(DEPMOD) ]; then $(DEPMOD) -ae -F System.map $(depmod_opts) $(KERNELRELEASE); fi
else # CONFIG_MODULES
# Modules not configured
# ---------------------------------------------------------------------------
modules modules_install: FORCE
@echo
@echo "The present busybox configuration has modules disabled."
@echo "Type 'make config' and enable loadable module support."
@echo "Then build a kernel with module support enabled."
@echo
@exit 1
endif # CONFIG_MODULES
###
# Cleaning is done on three levels.
# make clean Delete most generated files
# Leave enough to build external modules
# make mrproper Delete the current configuration, and all generated files
# make distclean Remove editor backup files, patch leftover files and the like
# Directories & files removed with 'make clean'
CLEAN_DIRS += $(MODVERDIR) _install 0_lib
CLEAN_FILES += busybox busybox_unstripped* busybox.links \
System.map .kernelrelease \
.tmp_kallsyms* .tmp_version .tmp_busybox* .tmp_System.map
# Directories & files removed with 'make mrproper'
MRPROPER_DIRS += include/config include2
MRPROPER_FILES += .config .config.old include/asm .version .old_version \
include/NUM_APPLETS.h \
include/common_bufsiz.h \
include/autoconf.h \
include/bbconfigopts.h \
include/bbconfigopts_bz2.h \
include/usage_compressed.h \
include/applet_tables.h \
include/applets.h \
include/usage.h \
applets/usage \
.kernelrelease Module.symvers tags TAGS cscope* \
busybox_old
# clean - Delete most, but leave enough to build external modules
#
clean: rm-dirs := $(CLEAN_DIRS)
clean: rm-files := $(CLEAN_FILES)
clean-dirs := $(addprefix _clean_,$(srctree) $(busybox-alldirs))