# =========================================================================== # kbuild: Generic definitions # =========================================================================== # Standard vars comma := , empty := space := $(empty) $(empty) # Backward compatibility - to be removed... extra-y += $(EXTRA_TARGETS) # 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) __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 object multi-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)))) 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 do not live # in the local directory subdir-obj-y := $(foreach o,$(obj-y),$(if $(filter-out $(o),$(notdir $(o))),$(o))) # $(obj-dirs) is a list of directories that contain object files obj-dirs := $(dir $(multi-objs) $(subdir-obj-y)) # Replace multi-part objects by their individual parts, look at local dir only real-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=-objs)) $($(m:.o=-y)),$(m))) # Add subdir path extra-y := $(addprefix $(obj)/,$(extra-y)) always := $(addprefix $(obj)/,$(always)) targets := $(addprefix $(obj)/,$(targets)) 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)) # The temporary file to save gcc -MD generated dependencies must not # contain a comma depfile = $(subst $(comma),_,$(@D)/.$(@F).d) # These flags are needed for modversions and compiling, so we define them here # already # $(modname_flags) #defines KBUILD_MODNAME as the name of the module it will # end up in (or would, if it gets compiled in) # Note: It's possible that one object gets potentially linked into more # than one module. In that case KBUILD_MODNAME will be set to foo_bar, # where foo and bar are the name of the modules. basename_flags = -DKBUILD_BASENAME=$(subst $(comma),_,$(subst -,_,$(*F))) modname_flags = $(if $(filter 1,$(words $(modname))),-DKBUILD_MODNAME=$(subst $(comma),_,$(subst -,_,$(modname)))) _c_flags = $(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$(*F).o) _a_flags = $(AFLAGS) $(EXTRA_AFLAGS) $(AFLAGS_$(*F).o) _cpp_flags = $(CPPFLAGS) $(EXTRA_CPPFLAGS) $(CPPFLAGS_$(@F)) # 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 # Prefix -I with $(srctree) if it is not an absolute path addtree = $(if $(filter-out -I/%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1))) $(1) # Find all -I options and call addtree flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o))) # -I$(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 = $(call addtree,-I$(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) $(CPPFLAGS) \ $(__c_flags) $(modkern_cflags) \ $(basename_flags) $(modname_flags) a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(CPPFLAGS) \ $(__a_flags) $(modkern_aflags) cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(__cpp_flags) ld_flags = $(LDFLAGS) $(EXTRA_LDFLAGS) # Finds the multi-part object the current object will be linked into modname-multi = $(sort $(foreach m,$(multi-used),\ $(if $(filter $(subst $(obj)/,,$*.o), $($(m:.o=-objs)) $($(m:.o=-y))),$(m:.o=)))) # 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_TARGETS so that we know we have to # read in the saved command line # Linking # --------------------------------------------------------------------------- quiet_cmd_ld = LD $@ cmd_ld = $(LD) $(LDFLAGS) $(EXTRA_LDFLAGS) $(LDFLAGS_$(@F)) \ $(filter-out FORCE,$^) -o $@ # Objcopy # --------------------------------------------------------------------------- quiet_cmd_objcopy = OBJCOPY $@ cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ # Gzip # --------------------------------------------------------------------------- quiet_cmd_gzip = GZIP $@ cmd_gzip = gzip -f -9 < $< > $@ # =========================================================================== # Generic stuff # =========================================================================== ifneq ($(KBUILD_NOCMDDEP),1) # Check if both arguments has same arguments. Result in empty string if equal # User may override this check using make KBUILD_NOCMDDEP=1 arg-check = $(strip $(filter-out $(1), $(2)) $(filter-out $(2), $(1)) ) endif # echo command. Short version is $(quiet) equals quiet, otherwise full command echo-cmd = $(if $($(quiet)cmd_$(1)), \ echo ' $(subst ','\'',$($(quiet)cmd_$(1)))';) # function to only execute the passed command if necessary # >'< substitution is for echo to work, >$< substitution to preserve $ when reloading .cmd file # note: when using inline perl scripts [perl -e '...$$t=1;...'] in $(cmd_xxx) double $$ your perl vars # if_changed = $(if $(strip $? $(call arg-check, $(cmd_$(1)), $(cmd_$@)) ), \ @set -e; \ $(echo-cmd) \ $(cmd_$(1)); \ echo 'cmd_$@ := $(subst $$,$$$$,$(subst ','\'',$(cmd_$(1))))' > $(@D)/.$(@F).cmd) # execute the command and also postprocess generated .d dependencies # file if_changed_dep = $(if $(strip $? $(filter-out FORCE $(wildcard $^),$^)\ $(call arg-check, $(cmd_$(1)), $(cmd_$@)) ), \ @set -e; \ $(echo-cmd) \ $(cmd_$(1)); \ scripts/basic/fixdep $(depfile) $@ '$(subst $$,$$$$,$(subst ','\'',$(cmd_$(1))))' > $(@D)/.$(@F).tmp; \ rm -f $(depfile); \ mv -f $(@D)/.$(@F).tmp $(@D)/.$(@F).cmd) # Usage: $(call if_changed_rule,foo) # will check if $(cmd_foo) changed, or any of the prequisites changed, # and if so will execute $(rule_foo) if_changed_rule = $(if $(strip $? $(call arg-check, $(cmd_$(1)), $(cmd_$@)) ),\ @set -e; \ $(rule_$(1))) # If quiet is set, only print short version of command cmd = @$(if $($(quiet)cmd_$(1)),echo ' $(subst ','\'',$($(quiet)cmd_$(1)))' &&) $(cmd_$(1)) # $(call descend,<dir>,<target>) # Recursively call a sub-make in <dir> with target <target> # Usage is deprecated, because make do not see this as an invocation of make. descend =$(Q)$(MAKE) -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj=$(1) $(2) # Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj= # Usage: # $(Q)$(MAKE) $(build)=dir build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj # filechk is used to check if the content of a generated file is updated. # Sample usage: # define filechk_sample # echo $KERNELRELEASE # endef # version.h : Makefile # $(call filechk,sample) # The rule defined shall write to stdout the content of the new file. # The existing file will be compared with the new one. # - If no file exist it is created # - If the content differ the new file is used # - If they are equal no change, and no timestamp update define filechk $(Q)set -e; \ echo ' CHK $@'; \ mkdir -p $(dir $@); \ $(filechk_$(1)) $(2) > $@.tmp; \ if [ -r $@ ] && cmp -s $@ $@.tmp; then \ rm -f $@.tmp; \ else \ echo ' UPD $@'; \ mv -f $@.tmp $@; \ fi endef