# Backward compatibilityasflags-y  += $(EXTRA_AFLAGS)ccflags-y  += $(EXTRA_CFLAGS)cppflags-y += $(EXTRA_CPPFLAGS)ldflags-y  += $(EXTRA_LDFLAGS) ## flags that take effect in sub directoriesexport KBUILD_SUBDIR_ASFLAGS := $(KBUILD_SUBDIR_ASFLAGS) $(subdir-asflags-y)export KBUILD_SUBDIR_CCFLAGS := $(KBUILD_SUBDIR_CCFLAGS) $(subdir-ccflags-y) # Figure out what we need to build from the various variables# =========================================================================== # When an object is listed to be built compiled-in and modular,# only build the compiled-in version obj-m := $(filter-out $(obj-y),$(obj-m)) # Libraries are always collected in one lib file.# Filter out objects already built-in lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))  # Handle objects in subdirs# ---------------------------------------------------------------------------# o if we encounter foo/ in $(obj-y), replace it by foo/built-in.o#   and add the directory to the list of dirs to descend into: $(subdir-y)# o if we encounter foo/ in $(obj-m), remove it from $(obj-m)#   and add the directory to the list of dirs to descend into: $(subdir-m) # Determine modorder.# Unfortunately, we don't have information about ordering between -y# and -m subdirs.  Just put -y's first.modorder	:= $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko)) __subdir-y	:= $(patsubst %/,%,$(filter %/, $(obj-y)))subdir-y	+= $(__subdir-y)__subdir-m	:= $(patsubst %/,%,$(filter %/, $(obj-m)))subdir-m	+= $(__subdir-m)obj-y		:= $(patsubst %/, %/built-in.o, $(obj-y))obj-m		:= $(filter-out %/, $(obj-m)) # Subdirectories we need to descend into subdir-ym	:= $(sort $(subdir-y) $(subdir-m)) # if $(foo-objs) exists, foo.o is a composite objectmulti-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m))))multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))), $(m))))multi-used   := $(multi-used-y) $(multi-used-m)single-used-m := $(sort $(filter-out $(multi-used-m),$(obj-m))) # Build list of the parts of our composite objects, our composite# objects depend on those (obviously)multi-objs-y := $(foreach m, $(multi-used-y), $($(m:.o=-objs)) $($(m:.o=-y)))multi-objs-m := $(foreach m, $(multi-used-m), $($(m:.o=-objs)) $($(m:.o=-y)))multi-objs   := $(multi-objs-y) $(multi-objs-m) # $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to# tell kbuild to descendsubdir-obj-y := $(filter %/built-in.o, $(obj-y)) # $(obj-dirs) is a list of directories that contain object filesobj-dirs := $(dir $(multi-objs) $(obj-y)) # Replace multi-part objects by their individual parts, look at local dir onlyreal-objs-y := $(foreach m, $(filter-out $(subdir-obj-y), $(obj-y)), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) $(extra-y)real-objs-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)),$(m))) # Add subdir path extra-y		:= $(addprefix $(obj)/,$(extra-y))always		:= $(addprefix $(obj)/,$(always))targets		:= $(addprefix $(obj)/,$(targets))modorder	:= $(addprefix $(obj)/,$(modorder))obj-y		:= $(addprefix $(obj)/,$(obj-y))obj-m		:= $(addprefix $(obj)/,$(obj-m))lib-y		:= $(addprefix $(obj)/,$(lib-y))subdir-obj-y	:= $(addprefix $(obj)/,$(subdir-obj-y))real-objs-y	:= $(addprefix $(obj)/,$(real-objs-y))real-objs-m	:= $(addprefix $(obj)/,$(real-objs-m))single-used-m	:= $(addprefix $(obj)/,$(single-used-m))multi-used-y	:= $(addprefix $(obj)/,$(multi-used-y))multi-used-m	:= $(addprefix $(obj)/,$(multi-used-m))multi-objs-y	:= $(addprefix $(obj)/,$(multi-objs-y))multi-objs-m	:= $(addprefix $(obj)/,$(multi-objs-m))subdir-ym	:= $(addprefix $(obj)/,$(subdir-ym))obj-dirs	:= $(addprefix $(obj)/,$(obj-dirs)) # These flags are needed for modversions and compiling, so we define them here# already# $(modname_flags) #defines KBUILD_MODNAME as the name of the module it will# end up in (or would, if it gets compiled in)# Note: Files that end up in two or more modules are compiled without the#       KBUILD_MODNAME definition. The reason is that any made-up name would#       differ in different configs.name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote)basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))modname_flags  = $(if $(filter 1,$(words $(modname))),\                 -DKBUILD_MODNAME=$(call name-fix,$(modname))) orig_c_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(KBUILD_SUBDIR_CCFLAGS) \                 $(ccflags-y) $(CFLAGS_$(basetarget).o)_c_flags       = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags))orig_a_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(KBUILD_SUBDIR_ASFLAGS) \                 $(asflags-y) $(AFLAGS_$(basetarget).o)_a_flags       = $(filter-out $(AFLAGS_REMOVE_$(basetarget).o), $(orig_a_flags))_cpp_flags     = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F)) ## Enable gcov profiling flags for a file, directory or for all files depending# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL# (in this order)#ifeq ($(CONFIG_GCOV_KERNEL),y)_c_flags += $(if $(patsubst n%,, \		$(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \		$(CFLAGS_GCOV))endif ## Enable address sanitizer flags for kernel except some files or directories# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE)#ifeq ($(CONFIG_KASAN),y)_c_flags += $(if $(patsubst n%,, \		$(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \		$(CFLAGS_KASAN))endif ifeq ($(CONFIG_UBSAN),y)_c_flags += $(if $(patsubst n%,, \		$(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \		$(CFLAGS_UBSAN))endif ifeq ($(CONFIG_KCOV),y)_c_flags += $(if $(patsubst n%,, \	$(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \	$(CFLAGS_KCOV))endif # If building the kernel in a separate objtree expand all occurrences# of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/'). ifeq ($(KBUILD_SRC),)__c_flags	= $(_c_flags)__a_flags	= $(_a_flags)__cpp_flags     = $(_cpp_flags)else # -I$(obj) locates generated .h files# $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files#   and locates generated .h files# FIXME: Replace both with specific CFLAGS* statements in the makefiles__c_flags	= $(if $(obj),$(call addtree,-I$(src)) -I$(obj)) \		  $(call flags,_c_flags)__a_flags	= $(call flags,_a_flags)__cpp_flags     = $(call flags,_cpp_flags)endif c_flags        = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \		 $(__c_flags) $(modkern_cflags)                           \		 $(basename_flags) $(modname_flags) a_flags        = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \		 $(__a_flags) $(modkern_aflags) cpp_flags      = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \		 $(__cpp_flags) ld_flags       = $(LDFLAGS) $(ldflags-y) DTC_INCLUDE    := $(srctree)/scripts/dtc/include-prefixes dtc_cpp_flags  = -Wp,-MD,$(depfile).pre.tmp -nostdinc                    \		 $(addprefix -I,$(DTC_INCLUDE))                          \		 -undef -D__DTS__ # Finds the multi-part object the current object will be linked intomodname-multi = $(sort $(foreach m,$(multi-used),\		$(if $(filter $(subst $(obj)/,,$*.o), $($(m:.o=-objs)) $($(m:.o=-y))),$(m:.o=)))) # Useful for describing the dependency of composite objects# Usage:#   $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)define multi_depend$(foreach m, $(notdir $1), \	$(eval $(obj)/$m: \	$(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s)))))))endef ifdef REGENERATE_PARSERS # LEX# ---------------------------------------------------------------------------LEX_PREFIX = $(if $(LEX_PREFIX_${baseprereq}),$(LEX_PREFIX_${baseprereq}),yy) quiet_cmd_flex = LEX     $@      cmd_flex = flex -o$@ -L -P $(LEX_PREFIX) $< .PRECIOUS: $(src)/%.lex.c_shipped$(src)/%.lex.c_shipped: $(src)/%.l	$(call cmd,flex) # YACC# ---------------------------------------------------------------------------YACC_PREFIX = $(if $(YACC_PREFIX_${baseprereq}),$(YACC_PREFIX_${baseprereq}),yy) quiet_cmd_bison = YACC    $@      cmd_bison = bison -o$@ -t -l -p $(YACC_PREFIX) $< .PRECIOUS: $(src)/%.tab.c_shipped$(src)/%.tab.c_shipped: $(src)/%.y	$(call cmd,bison) quiet_cmd_bison_h = YACC    $@      cmd_bison_h = bison -o/dev/null --defines=$@ -t -l -p $(YACC_PREFIX) $< .PRECIOUS: $(src)/%.tab.h_shipped$(src)/%.tab.h_shipped: $(src)/%.y	$(call cmd,bison_h) endif # Shipped files# =========================================================================== quiet_cmd_shipped = SHIPPED $@cmd_shipped = cat $< > $@ $(obj)/%: $(src)/%_shipped	$(call cmd,shipped) # Commands useful for building a boot image# ===========================================================================##	Use as following:##	target: source(s) FORCE#		$(if_changed,ld/objcopy/gzip)##	and add target to extra-y so that we know we have to#	read in the saved command line # Linking# --------------------------------------------------------------------------- quiet_cmd_ld = LD      $@cmd_ld = $(LD) $(LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) \	       $(filter-out FORCE,$^) -o $@ # Objcopy# --------------------------------------------------------------------------- quiet_cmd_objcopy = OBJCOPY $@cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ # Gzip# --------------------------------------------------------------------------- quiet_cmd_gzip = GZIP    $@cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@) || \	(rm -f $@ ; false) # DTC# ---------------------------------------------------------------------------DTC ?= $(objtree)/scripts/dtc/dtc # Disable noisy checks by defaultifeq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),)DTC_FLAGS += -Wno-unit_address_vs_reg \	-Wno-simple_bus_reg \	-Wno-unit_address_format \	-Wno-pci_bridge \	-Wno-pci_device_bus_num \	-Wno-pci_device_regendif ifeq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),2)DTC_FLAGS += -Wnode_name_chars_strict \	-Wproperty_name_chars_strictendif DTC_FLAGS += $(DTC_FLAGS_$(basetarget)) # Generate an assembly file to wrap the output of the device tree compilerquiet_cmd_dt_S_dtb= DTB     $@cmd_dt_S_dtb=						\(							\	echo '\#include <asm-generic/vmlinux.lds.h>'; 	\	echo '.section .dtb.init.rodata,"a"';		\	echo '.balign STRUCT_ALIGNMENT';		\	echo '.global __dtb_$(*F)_begin';		\	echo '__dtb_$(*F)_begin:';			\	echo '.incbin "$<" ';				\	echo '__dtb_$(*F)_end:';			\	echo '.global __dtb_$(*F)_end';			\	echo '.balign STRUCT_ALIGNMENT'; 		\) > $@ $(obj)/%.dtb.S: $(obj)/%.dtb	$(call cmd,dt_S_dtb) quiet_cmd_dtc = DTC     $@cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \	$(CPP) $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \	$(DTC) -O dtb -o $@ -b 0 \		$(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \		-d $(depfile).dtc.tmp $(dtc-tmp) ; \	cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile) $(obj)/%.dtb: $(src)/%.dts FORCE	$(call if_changed_dep,dtc) dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp) # Bzip2# --------------------------------------------------------------------------- # Bzip2 and LZMA do not include size in file... so we have to fake that;# append the size as a 32-bit littleendian number as gzip does.size_append = printf $(shell						\dec_size=0;								\for F in $1; do								\	fsize=$$(stat -c "%s" $$F);					\	dec_size=$$(expr $$dec_size + $$fsize);				\done;									\printf "%08x\n" $$dec_size |						\	sed 's/\(..\)/\1 /g' | {					\		read ch0 ch1 ch2 ch3;					\		for ch in $$ch3 $$ch2 $$ch1 $$ch0; do			\			printf '%s%03o' '\\' $$((0x$$ch)); 		\		done;							\	}								\) quiet_cmd_bzip2 = BZIP2   $@cmd_bzip2 = (cat $(filter-out FORCE,$^) | \	bzip2 -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \	(rm -f $@ ; false) # Lzma# --------------------------------------------------------------------------- quiet_cmd_lzma = LZMA    $@cmd_lzma = (cat $(filter-out FORCE,$^) | \	lzma -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \	(rm -f $@ ; false) quiet_cmd_lzo = LZO     $@cmd_lzo = (cat $(filter-out FORCE,$^) | \	lzop -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \	(rm -f $@ ; false) quiet_cmd_lz4 = LZ4     $@cmd_lz4 = (cat $(filter-out FORCE,$^) | \	lz4c -l -c1 stdin stdout && $(call size_append, $(filter-out FORCE,$^))) > $@ || \	(rm -f $@ ; false) # U-Boot mkimage# --------------------------------------------------------------------------- MKIMAGE := $(srctree)/scripts/mkuboot.sh # SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces# the number of overrides in arch makefilesUIMAGE_ARCH ?= $(SRCARCH)UIMAGE_COMPRESSION ?= $(if $(2),$(2),none)UIMAGE_OPTS-y ?=UIMAGE_TYPE ?= kernelUIMAGE_LOADADDR ?= arch_must_set_thisUIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)'UIMAGE_IN ?= $<UIMAGE_OUT ?= $@ quiet_cmd_uimage = UIMAGE  $(UIMAGE_OUT)      cmd_uimage = $(CONFIG_SHELL) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \			-C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \			-T $(UIMAGE_TYPE) \			-a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \			-n $(UIMAGE_NAME) -d $(UIMAGE_IN) $(UIMAGE_OUT) # XZ# ---------------------------------------------------------------------------# Use xzkern to compress the kernel image and xzmisc to compress other things.## xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage# of the kernel decompressor. A BCJ filter is used if it is available for# the target architecture. xzkern also appends uncompressed size of the data# using size_append. The .xz format has the size information available at# the end of the file too, but it's in more complex format and it's good to# avoid changing the part of the boot code that reads the uncompressed size.# Note that the bytes added by size_append will make the xz tool think that# the file is corrupt. This is expected.## xzmisc doesn't use size_append, so it can be used to create normal .xz# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very# big dictionary would increase the memory usage too much in the multi-call# decompression mode. A BCJ filter isn't used either.quiet_cmd_xzkern = XZKERN  $@cmd_xzkern = (cat $(filter-out FORCE,$^) | \	sh $(srctree)/scripts/xz_wrap.sh && \	$(call size_append, $(filter-out FORCE,$^))) > $@ || \	(rm -f $@ ; false) quiet_cmd_xzmisc = XZMISC  $@cmd_xzmisc = (cat $(filter-out FORCE,$^) | \	xz --check=crc32 --lzma2=dict=1MiB) > $@ || \	(rm -f $@ ; false) # ASM offsets# --------------------------------------------------------------------------- # Default sed regexp - multiline due to syntax constraints## Use [:space:] because LLVM's integrated assembler inserts <tab> around# the .ascii directive whereas GCC keeps the <space> as-is.define sed-offsets	's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \	/^->/{s:->#\(.*\):/* \1 */:; \	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \	s:->::; p;}'endef # Use filechk to avoid rebuilds when a header changes, but the resulting file# does notdefine filechk_offsets	(set -e; \	 echo "#ifndef $2"; \	 echo "#define $2"; \	 echo "/*"; \	 echo " * DO NOT MODIFY."; \	 echo " *"; \	 echo " * This file was generated by Kbuild"; \	 echo " */"; \	 echo ""; \	 sed -ne $(sed-offsets); \	 echo ""; \	 echo "#endif" )endef