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 $(obj)=" with a shorthand.) This means the current working directory is always the top of the output directory. Signed-off-by: Masahiro Yamada Tested-by: Gerhard Sittig --- arch/powerpc/lib/Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/lib/Makefile') diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile index a706d3cc70..ac780d4077 100644 --- a/arch/powerpc/lib/Makefile +++ b/arch/powerpc/lib/Makefile @@ -54,11 +54,11 @@ ifndef CONFIG_SPL_BUILD # Workaround for local bus unaligned access problems # on MPC512x and MPC5200 ifdef CONFIG_MPC512X -$(obj)ppcstring.o: AFLAGS += -Dmemcpy=__memcpy +$(obj)/ppcstring.o: AFLAGS += -Dmemcpy=__memcpy obj-y += memcpy_mpc5200.o endif ifdef CONFIG_MPC5200 -$(obj)ppcstring.o: AFLAGS += -Dmemcpy=__memcpy +$(obj)/ppcstring.o: AFLAGS += -Dmemcpy=__memcpy obj-y += memcpy_mpc5200.o endif endif -- cgit