From 9e4140329ee9a787d0f96ac2829d618d47f7973f Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 4 Feb 2014 17:24:24 +0900 Subject: kbuild: change out-of-tree build This commit changes the working directory where the build process occurs. Before this commit, build process occurred under the source tree for both in-tree and out-of-tree build. That's why we needed to add $(obj) prefix to all generated files in makefiles like follows: $(obj)u-boot.bin: $(obj)u-boot Here, $(obj) is empty for in-tree build, whereas it points to the output directory for out-of-tree build. And our old build system changes the current working directory with "make -C " syntax when descending into the sub-directories. On the other hand, Kbuild uses a different idea to handle out-of-tree build and directory descending. The build process of Kbuild always occurs under the output tree. When "O=dir/to/store/output/files" is given, the build system changes the current working directory to that directory and restarts the make. Kbuild uses "make -f $(srctree)/scripts/Makefile.build obj=" syntax for descending into sub-directories. (We can write it like "make $(obj)=" with a shorthand.) This means the current working directory is always the top of the output directory. Signed-off-by: Masahiro Yamada Tested-by: Gerhard Sittig --- common/Makefile | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'common') diff --git a/common/Makefile b/common/Makefile index 2fe14ccc41..2d75843628 100644 --- a/common/Makefile +++ b/common/Makefile @@ -238,11 +238,10 @@ obj-$(CONFIG_FIT_SIGNATURE) += image-sig.o obj-y += memsize.o obj-y += stdio.o -$(obj)env_embedded.o: $(src)env_embedded.c +$(obj)/env_embedded.o: $(src)/env_embedded.c $(CC) $(AFLAGS) -Wa,--no-warn \ - -DENV_CRC=$(shell $(obj)../tools/envcrc) \ - -c -o $@ $(src)env_embedded.c + -DENV_CRC=$(shell tools/envcrc) -c -o $@ $< # SEE README.arm-unaligned-accesses -$(obj)hush.o: CFLAGS += $(PLATFORM_NO_UNALIGNED) -$(obj)fdt_support.o: CFLAGS += $(PLATFORM_NO_UNALIGNED) +$(obj)/hush.o: CFLAGS += $(PLATFORM_NO_UNALIGNED) +$(obj)/fdt_support.o: CFLAGS += $(PLATFORM_NO_UNALIGNED) -- cgit v1.2.3