Makefile: support descending down to subdirectories
This patch tweaks scripts/Makefile.build to allow
the build system to descend into subdirectories like Kbuild.
To use this feature, use "obj-y += foo/" syntax.
Example:
obj-$(CONFIG_FOO) += foo/
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Simon Glass <sjg@chromium.org>
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index f969ec5..2ef7341 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -19,6 +19,11 @@
extra-y := $(sort $(extra-y))
lib-y := $(sort $(lib-y))
+subdir-y := $(patsubst %/,%,$(filter %/, $(obj-y)))
+obj-y := $(patsubst %/, %/built-in.o, $(obj-y))
+subdir-obj-y := $(filter %/built-in.o, $(obj-y))
+subdir-obj-y := $(addprefix $(obj),$(subdir-obj-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))
@@ -37,6 +42,14 @@
$(call cmd_link_o_target, $(LGOBJS))
endif
+ifneq ($(subdir-obj-y),)
+# Descending
+$(subdir-obj-y): $(subdir-y)
+
+$(subdir-y): FORCE
+ $(MAKE) -C $@ -f $(TOPDIR)/scripts/Makefile.build
+endif
+
#########################################################################
# defines $(obj).depend target
@@ -46,3 +59,5 @@
sinclude $(obj).depend
#########################################################################
+
+.PHONY: FORCE