From: Masahiro Yamada Date: Thu, 17 Oct 2013 08:34:47 +0000 (+0900) Subject: Makefile: prepare for using Kbuild-style Makefile X-Git-Tag: v2014.01-rc1~178 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=ce28d7ac6d64c8a730334c8584742cf7255ad318;p=oweals%2Fu-boot.git Makefile: prepare for using Kbuild-style Makefile Every makefile in sub directories has common lines at the top and the bottom. This commit pushes the common parts into script/Makefile.build. Going forward sub-makefiles only need to describe this part: COBJS := ... COBJS += ... SOBJS := ... But using obj-y is preferable to prepare for switching to Kbuild. The conventional (non-Kbuild) Makefile style is still supported. This is achieved by greping the Makefile before entering into it. U-Boot conventional sub makefiles always include some other makefiles. So the build system searches a line beginning with "include" keyword in the makefile in order to distinguish which style it is. If the Makefile include a "include" line, we assume it is a conventional U-Boot style. Otherwise, it is treated as a Kbuild-style makefile. With this tweak, we can switch sub-makefiles from U-Boot style to Kbuild style little by little. obj-y := foo/ syntax (descending into the sub directory) is not supportd yet. It will be implemented in the upcomming commit. Signed-off-by: Masahiro Yamada Cc: Simon Glass Cc: Tom Rini --- diff --git a/Makefile b/Makefile index 2d18d27639..1840dac45a 100644 --- a/Makefile +++ b/Makefile @@ -595,14 +595,32 @@ ifeq ($(CONFIG_KALLSYMS),y) $(GEN_UBOOT) $(obj)common/system_map.o endif +# Tentative step for Kbuild-style makefiles coexist with conventional U-Boot style makefiles +# U-Boot conventional sub makefiles always include some other makefiles. +# So, the build system searches a line beginning with "include" before entering into the sub makefile +# in order to distinguish which style it is. +# If the Makefile include a "include" line, we assume it is an U-Boot style makefile. +# Otherwise, it is treated as a Kbuild-style makefile. +select_makefile = \ + +if grep -q "^include" $1/Makefile; then \ + $(MAKE) -C $1; \ + else \ + $(MAKE) -C $1 -f $(TOPDIR)/scripts/Makefile.build; \ + mv $(dir $@)built-in.o $@; \ + fi + +# We do not need to build $(OBJS) explicitly. +# It is built while we are at $(CPUDIR)/lib$(CPU).o build. $(OBJS): depend - $(MAKE) -C $(CPUDIR) $(if $(REMOTE_BUILD),$@,$(notdir $@)) + if grep -q "^include" $(CPUDIR)/Makefile; then \ + $(MAKE) -C $(CPUDIR) $(if $(REMOTE_BUILD),$@,$(notdir $@)); \ + fi $(LIBS): depend $(SUBDIR_TOOLS) - $(MAKE) -C $(dir $(subst $(obj),,$@)) + +$(call select_makefile, $(dir $(subst $(obj),,$@))) $(LIBBOARD): depend $(LIBS) - $(MAKE) -C $(dir $(subst $(obj),,$@)) + +$(call select_makefile, $(dir $(subst $(obj),,$@))) $(SUBDIRS): depend $(MAKE) -C $@ all @@ -630,6 +648,13 @@ $(obj)tpl/u-boot-tpl.bin: $(SUBDIR_TOOLS) depend updater: $(MAKE) -C tools/updater all +select_makefile2 = \ + if grep -q "^include" $1/Makefile; then \ + $(MAKE) -C $1 _depend; \ + else \ + $(MAKE) -C $1 -f $(TOPDIR)/scripts/Makefile.build _depend; \ + fi + # Explicitly make _depend in subdirs containing multiple targets to prevent # parallel sub-makes creating .depend files simultaneously. depend dep: $(TIMESTAMP_FILE) $(VERSION_FILE) \ @@ -638,8 +663,9 @@ depend dep: $(TIMESTAMP_FILE) $(VERSION_FILE) \ $(obj)include/autoconf.mk \ $(obj)include/generated/generic-asm-offsets.h \ $(obj)include/generated/asm-offsets.h - for dir in $(SUBDIRS) $(CPUDIR) $(LDSCRIPT_MAKEFILE_DIR) ; do \ - $(MAKE) -C $$dir _depend ; done + +for dir in $(SUBDIRS) $(CPUDIR) $(LDSCRIPT_MAKEFILE_DIR) ; do \ + $(call select_makefile2, $$dir); \ + done TAG_SUBDIRS = $(SUBDIRS) TAG_SUBDIRS += $(dir $(__LIBS)) diff --git a/scripts/Makefile.build b/scripts/Makefile.build new file mode 100644 index 0000000000..f969ec55bd --- /dev/null +++ b/scripts/Makefile.build @@ -0,0 +1,48 @@ +# our default target +.PHONY: all +all: + +include $(TOPDIR)/config.mk + +LIB := $(obj)built-in.o +LIBGCC = $(obj)libgcc.o +SRCS := + +include Makefile + +# Backward compatible: obj-y is preferable +COBJS := $(sort $(COBJS) $(COBJS-y)) +SOBJS := $(sort $(SOBJS) $(SOBJS-y)) + +# Going forward use the following +obj-y := $(sort $(obj-y)) +extra-y := $(sort $(extra-y)) +lib-y := $(sort $(lib-y)) + +SRCS += $(COBJS:.o=.c) $(SOBJS:.o=.S) \ + $(wildcard $(obj-y:.o=.c) $(obj-y:.o=.S) $(lib-y:.o=.c) $(lib-y:.o=.S) $(extra-y:.o=.c) $(extra-y:.o=.S)) +OBJS := $(addprefix $(obj),$(COBJS) $(SOBJS) $(obj-y)) + +LGOBJS := $(addprefix $(obj),$(sort $(GLSOBJS) $(GLCOBJS)) $(lib-y)) + +all: $(LIB) $(addprefix $(obj),$(extra-y)) + +$(LIB): $(obj).depend $(OBJS) + $(call cmd_link_o_target, $(OBJS)) + +ifneq ($(strip $(lib-y)),) +all: $(LIBGCC) + +$(LIBGCC): $(obj).depend $(LGOBJS) + $(call cmd_link_o_target, $(LGOBJS)) +endif + +######################################################################### + +# defines $(obj).depend target + +include $(TOPDIR)/rules.mk + +sinclude $(obj).depend + +######################################################################### diff --git a/spl/Makefile b/spl/Makefile index b366ac2bb7..64ebfb7090 100644 --- a/spl/Makefile +++ b/spl/Makefile @@ -200,11 +200,29 @@ GEN_UBOOT = \ $(obj)$(SPL_BIN): depend $(START) $(LIBS) $(obj)u-boot-spl.lds $(GEN_UBOOT) +# Tentative step for Kbuild-style makefiles coexist with conventional U-Boot style makefiles +# U-Boot conventional sub makefiles always include some other makefiles. +# So, the build system searches a line beginning with "include" before entering into the sub makefile +# in order to distinguish which style it is. +# If the Makefile include a "include" line, we assume it is an U-Boot style makefile. +# Otherwise, it is treated as a Kbuild-style makefile. +select_makefile = \ + if grep -q "^include" $1/Makefile; then \ + $(MAKE) -C $1; \ + else \ + $(MAKE) -C $1 -f $(TOPDIR)/scripts/Makefile.build; \ + mv $(dir $@)built-in.o $@; \ + fi + +# We do not need to build $(START) explicitly. +# It is built while we are at $(CPUDIR)/lib$(CPU).o build. $(START): depend - $(MAKE) -C $(SRCTREE)/$(START_PATH) $@ + if grep -q "^include" $(SRCTREE)$(dir $(subst $(SPLTREE),,$@))Makefile; then \ + $(MAKE) -C $(SRCTREE)/$(START_PATH) $@; \ + fi $(LIBS): depend - $(MAKE) -C $(SRCTREE)$(dir $(subst $(SPLTREE),,$@)) + +$(call select_makefile, $(SRCTREE)$(dir $(subst $(SPLTREE),,$@))) $(obj)u-boot-spl.lds: $(LDSCRIPT) depend $(CPP) $(CPPFLAGS) $(LDPPFLAGS) -I$(obj). -ansi -D__ASSEMBLY__ -P - < $< > $@