1# Backward compatibility 2asflags-y += $(EXTRA_AFLAGS) 3ccflags-y += $(EXTRA_CFLAGS) 4cppflags-y += $(EXTRA_CPPFLAGS) 5ldflags-y += $(EXTRA_LDFLAGS) 6 7# Figure out what we need to build from the various variables 8# =========================================================================== 9 10# When an object is listed to be built compiled-in and modular, 11# only build the compiled-in version 12 13obj-m := $(filter-out $(obj-y),$(obj-m)) 14 15# Libraries are always collected in one lib file. 16# Filter out objects already built-in 17 18lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m))) 19 20 21# Handle objects in subdirs 22# --------------------------------------------------------------------------- 23# o if we encounter foo/ in $(obj-y), replace it by foo/built-in.o 24# and add the directory to the list of dirs to descend into: $(subdir-y) 25# o if we encounter foo/ in $(obj-m), remove it from $(obj-m) 26# and add the directory to the list of dirs to descend into: $(subdir-m) 27 28__subdir-y := $(patsubst %/,%,$(filter %/, $(obj-y))) 29subdir-y += $(__subdir-y) 30__subdir-m := $(patsubst %/,%,$(filter %/, $(obj-m))) 31subdir-m += $(__subdir-m) 32obj-y := $(patsubst %/, %/built-in.o, $(obj-y)) 33obj-m := $(filter-out %/, $(obj-m)) 34 35# Subdirectories we need to descend into 36 37subdir-ym := $(sort $(subdir-y) $(subdir-m)) 38 39# if $(foo-objs) exists, foo.o is a composite object 40multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m)))) 41multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m)))) 42multi-used := $(multi-used-y) $(multi-used-m) 43single-used-m := $(sort $(filter-out $(multi-used-m),$(obj-m))) 44 45# Build list of the parts of our composite objects, our composite 46# objects depend on those (obviously) 47multi-objs-y := $(foreach m, $(multi-used-y), $($(m:.o=-objs)) $($(m:.o=-y))) 48multi-objs-m := $(foreach m, $(multi-used-m), $($(m:.o=-objs)) $($(m:.o=-y))) 49multi-objs := $(multi-objs-y) $(multi-objs-m) 50 51# $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to 52# tell kbuild to descend 53subdir-obj-y := $(filter %/built-in.o, $(obj-y)) 54 55# $(obj-dirs) is a list of directories that contain object files 56obj-dirs := $(dir $(multi-objs) $(subdir-obj-y)) 57 58# Replace multi-part objects by their individual parts, look at local dir only 59real-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) 60real-objs-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) 61 62# Add subdir path 63 64extra-y := $(addprefix $(obj)/,$(extra-y)) 65always := $(addprefix $(obj)/,$(always)) 66targets := $(addprefix $(obj)/,$(targets)) 67obj-y := $(addprefix $(obj)/,$(obj-y)) 68obj-m := $(addprefix $(obj)/,$(obj-m)) 69lib-y := $(addprefix $(obj)/,$(lib-y)) 70subdir-obj-y := $(addprefix $(obj)/,$(subdir-obj-y)) 71real-objs-y := $(addprefix $(obj)/,$(real-objs-y)) 72real-objs-m := $(addprefix $(obj)/,$(real-objs-m)) 73single-used-m := $(addprefix $(obj)/,$(single-used-m)) 74multi-used-y := $(addprefix $(obj)/,$(multi-used-y)) 75multi-used-m := $(addprefix $(obj)/,$(multi-used-m)) 76multi-objs-y := $(addprefix $(obj)/,$(multi-objs-y)) 77multi-objs-m := $(addprefix $(obj)/,$(multi-objs-m)) 78subdir-ym := $(addprefix $(obj)/,$(subdir-ym)) 79obj-dirs := $(addprefix $(obj)/,$(obj-dirs)) 80 81# These flags are needed for modversions and compiling, so we define them here 82# already 83# $(modname_flags) #defines KBUILD_MODNAME as the name of the module it will 84# end up in (or would, if it gets compiled in) 85# Note: It's possible that one object gets potentially linked into more 86# than one module. In that case KBUILD_MODNAME will be set to foo_bar, 87# where foo and bar are the name of the modules. 88name-fix = $(subst $(comma),_,$(subst -,_,$1)) 89basename_flags = -D"KBUILD_BASENAME=KBUILD_STR($(call name-fix,$(basetarget)))" 90modname_flags = $(if $(filter 1,$(words $(modname))),\ 91 -D"KBUILD_MODNAME=KBUILD_STR($(call name-fix,$(modname)))") 92 93_c_flags = $(KBUILD_CFLAGS) $(ccflags-y) $(CFLAGS_$(basetarget).o) 94_a_flags = $(KBUILD_AFLAGS) $(asflags-y) $(AFLAGS_$(basetarget).o) 95_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F)) 96 97# If building the kernel in a separate objtree expand all occurrences 98# of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/'). 99 100ifeq ($(KBUILD_SRC),) 101__c_flags = $(_c_flags) 102__a_flags = $(_a_flags) 103__cpp_flags = $(_cpp_flags) 104else 105 106# -I$(obj) locates generated .h files 107# $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files 108# and locates generated .h files 109# FIXME: Replace both with specific CFLAGS* statements in the makefiles 110__c_flags = $(call addtree,-I$(obj)) $(call flags,_c_flags) 111__a_flags = $(call flags,_a_flags) 112__cpp_flags = $(call flags,_cpp_flags) 113endif 114 115c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(KBUILD_CPPFLAGS) \ 116 $(__c_flags) $(modkern_cflags) \ 117 -D"KBUILD_STR(s)=\#s" $(basename_flags) $(modname_flags) 118 119a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(KBUILD_CPPFLAGS) \ 120 $(__a_flags) $(modkern_aflags) 121 122cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(__cpp_flags) 123 124ld_flags = $(LDFLAGS) $(ldflags-y) 125 126# Finds the multi-part object the current object will be linked into 127modname-multi = $(sort $(foreach m,$(multi-used),\ 128 $(if $(filter $(subst $(obj)/,,$*.o), $($(m:.o=-objs)) $($(m:.o=-y))),$(m:.o=)))) 129 130# Shipped files 131# =========================================================================== 132 133quiet_cmd_shipped = SHIPPED $@ 134cmd_shipped = cat $< > $@ 135 136$(obj)/%:: $(src)/%_shipped 137 $(call cmd,shipped) 138 139# Commands useful for building a boot image 140# =========================================================================== 141# 142# Use as following: 143# 144# target: source(s) FORCE 145# $(if_changed,ld/objcopy/gzip) 146# 147# and add target to extra-y so that we know we have to 148# read in the saved command line 149 150# Linking 151# --------------------------------------------------------------------------- 152 153quiet_cmd_ld = LD $@ 154cmd_ld = $(LD) $(LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) \ 155 $(filter-out FORCE,$^) -o $@ 156 157# Objcopy 158# --------------------------------------------------------------------------- 159 160quiet_cmd_objcopy = OBJCOPY $@ 161cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ 162 163# Gzip 164# --------------------------------------------------------------------------- 165 166quiet_cmd_gzip = GZIP $@ 167cmd_gzip = gzip -f -9 < $< > $@ 168 169 170