u-boot/arch/x86/lib/Makefile
Masahiro Yamada 9e4140329e 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 <sub-dir>" 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=<sub-dir>"
syntax for descending into sub-directories.
(We can write it like "make $(obj)=<sub-dir>" with a shorthand.)
This means the current working directory is always the top
of the output directory.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Tested-by: Gerhard Sittig <gsi@denx.de>
2014-02-19 11:07:50 -05:00

27 lines
689 B
Makefile

#
# (C) Copyright 2002-2006
# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
#
# SPDX-License-Identifier: GPL-2.0+
#
obj-$(CONFIG_CMD_BOOTM) += bootm.o
obj-y += cmd_boot.o
obj-y += gcc.o
obj-y += init_helpers.o
obj-y += interrupts.o
obj-$(CONFIG_SYS_PCAT_INTERRUPTS) += pcat_interrupts.o
obj-$(CONFIG_SYS_PCAT_TIMER) += pcat_timer.o
obj-$(CONFIG_PCI) += pci_type1.o
obj-y += relocate.o
obj-y += physmem.o
obj-y += string.o
obj-$(CONFIG_SYS_X86_TSC_TIMER) += tsc_timer.o
obj-$(CONFIG_VIDEO_VGA) += video.o
obj-$(CONFIG_CMD_ZBOOT) += zimage.o
LIBGCC := $(notdir $(NORMAL_LIBGCC))
extra-y := $(LIBGCC)
$(obj)/$(LIBGCC): $(NORMAL_LIBGCC)
$(OBJCOPY) $< $@ --prefix-symbols=__normal_