@@ -594,14 +594,32 @@ 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
@@ -629,6 +647,13 @@ $(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) \
@@ -637,8 +662,9 @@ 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))
new file mode 100644
@@ -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
+
+#########################################################################
@@ -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 - < $< > $@
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 <yamada.m@jp.panasonic.com> Cc: Simon Glass <sjg@chromium.org> Cc: Tom Rini <trini@ti.com> --- Changes for v3: - Re-write complicated parts with $(call select_makefile, ...) - Add indents - Shorten commit log and move verbose explanation below '---' Changes for v2: - fix commit log (purely cosmetic) Note1: (At first, I tried to grep "rules.mk" keyword instead of "^include", but I found it does not work. Almost all sub makefiles include "rules.mk", but there exist three exception: - board/avnet/fx12mm/Makefile - board/avnet/v5fx30teval/Makefile - board/xilinx/ml507/Makefile These three makefiles include "rules.mk" indirectly. Anyway, they look weird, so they should be fixed lator.) Note2: Note that this refactoring breaks nothing because it just moves the common parts into scripts/Makefile.build. Note3: Of course, scripts/Makefile.build added by this commit is temporary. It shall be replaced with the one of Linux Kernel in future. Note4: For v3, I pushed dirty stuff into select_makefile function. But this has a side effect. When invoking $(call select_makefile,...) , GNU make reports the warning make[1]: warning: jobserver unavailable: using -j1. Add `+' to parent make rule. To suppress this, I added '+' lile: +$(call select_makefile, $(dir $(subst $(obj),,$@))) Makefile | 36 +++++++++++++++++++++++++++++++----- scripts/Makefile.build | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ spl/Makefile | 22 ++++++++++++++++++++-- 3 files changed, 99 insertions(+), 7 deletions(-) create mode 100644 scripts/Makefile.build