u-boot的配置、编译及链接

OBJTREE := $(if $(BUILD_DIR),$(BUILD_DIR),$(CURDIR))
SRCTREE := $(CURDIR)
TOPDIR := $(SRCTREE)
LNDIR := $(OBJTREE)
export TOPDIR SRCTREE OBJTREEMKCONFIG := $(SRCTREE)/mkconfig
export MKCONFIGCCJ_config : unconfig
@$(MKCONFIG) $(@:_config=) arm arm920t CCJ NULL s3c24x0

@$(MKCONFIG) $(@:_config=) arm arm920t CCJ NULL s3c24x0

./mkconfig CCJ arm arm920t CCJ NULL s3c24x0

APPEND=no # Default: Create new config file
BOARD_NAME="" # Name to print in make outputwhile [ $# -gt ] ; do
case "$1" in
--) shift ; break ;;
-a) shift ; APPEND=yes ;;
-n) shift ; BOARD_NAME="${1%%_config}" ; shift ;;
*) break ;;
esac
done[ "${BOARD_NAME}" ] || BOARD_NAME="$1"[ $# -lt ] && exit
[ $# -gt ] && exit echo "Configuring for ${BOARD_NAME} board..."

Makefile命令： ./mkconfig CCJ arm arm920t CCJ NULL s3c24x0
mkconfig对应符号表示： $ $ $ $ $ $ $

if [ "$SRCTREE" != "$OBJTREE" ] ; then
mkdir -p ${OBJTREE}/include
mkdir -p ${OBJTREE}/include2
cd ${OBJTREE}/include2
rm -f asm
ln -s ${SRCTREE}/include/asm-$ asm
LNPREFIX="../../include2/asm/"
cd ../include
rm -rf asm-$
rm -f asm
mkdir asm-$
ln -s asm-$ asm
else
cd ./include
rm -f asm
ln -s asm-$ asm
firm -f asm-$/arch

OBJTREE := $(if $(BUILD_DIR),$(BUILD_DIR),$(CURDIR))
SRCTREE := $(CURDIR)

if [ -z "$6" -o "$6" = "NULL" ] ; then
ln -s ${LNPREFIX}arch-$ asm-$/arch
else
ln -s ${LNPREFIX}arch-$ asm-$/arch
fiif [ "$2" = "arm" ] ; then
rm -f asm-$/proc
ln -s ${LNPREFIX}proc-armv asm-$/proc
fi

#
# Create include file for Make
#
echo "ARCH = $2" > config.mk
echo "CPU = $3" >> config.mk
echo "BOARD = $4" >> config.mk[ "$5" ] && [ "$5" != "NULL" ] && echo "VENDOR = $5" >> config.mk[ "$6" ] && [ "$6" != "NULL" ] && echo "SOC = $6" >> config.mk#
# Create board specific header file
#
if [ "$APPEND" = "yes" ] # Append to existing config file
then
echo >> config.h
else
> config.h # Create new config file
fi
echo "/* Automatically generated - do not edit */" >>config.h
echo "#include <configs/$1.h>" >>config.hexit

ARCH = arm
CPU = arm920t
BOARD = CCJ
SOC = s3c24x0

# load ARCH, BOARD, and CPU configuration
include $(OBJTREE)/include/config.mk
export ARCH CPU BOARD VENDOR SOCifndef CROSS_COMPILE
ifeq ($(HOSTARCH),ppc)
CROSS_COMPILE =
else
ifeq ($(ARCH),ppc)
CROSS_COMPILE = powerpc-linux-
endif
ifeq ($(ARCH),arm)
CROSS_COMPILE = arm-linux-
endif
ifeq ($(ARCH),i386)
ifeq ($(HOSTARCH),i386)
CROSS_COMPILE =
else
CROSS_COMPILE = i386-linux-
endif
endif

export CROSS_COMPILE# load other configuration
include $(TOPDIR)/config.mk

ifeq ($(ARCH),arm)
ifeq ($(CROSS_COMPILE),powerpc-netbsd-)
PLATFORM_CPPFLAGS+= -D__ARM__
endif
ifeq ($(CROSS_COMPILE),powerpc-openbsd-)
PLATFORM_CPPFLAGS+= -D__ARM__
endif
endififeq ($(ARCH),blackfin)
PLATFORM_CPPFLAGS+= -D__BLACKFIN__ -mno-underscore
endififdef ARCH
sinclude $(TOPDIR)/$(ARCH)_config.mk # include architecture dependend rules
endif
ifdef CPU
sinclude $(TOPDIR)/cpu/$(CPU)/config.mk # include CPU specific rules
endif
ifdef SOC
sinclude $(TOPDIR)/cpu/$(CPU)/$(SOC)/config.mk # include SoC specific rules
endif

# U-Boot objects....order is important (i.e. start must be first)OBJS = cpu/$(CPU)/start.o
OBJS := $(addprefix $(obj),$(OBJS))LIBS = lib_generic/libgeneric.a
LIBS += board/$(BOARDDIR)/lib$(BOARD).a
LIBS += cpu/$(CPU)/lib$(CPU).a
ifdef SOC
LIBS += cpu/$(CPU)/$(SOC)/lib$(SOC).a
endif
LIBS += lib_$(ARCH)/lib$(ARCH).a
LIBS += fs/cramfs/libcramfs.a fs/fat/libfat.a fs/fdos/libfdos.a

$(OBJS):
echo $(OBJS)
$(MAKE) -C cpu/$(CPU) $(if $(REMOTE_BUILD),$@,$(notdir $@))$(LIBS):
$(MAKE) -C $(dir $(subst $(obj),,$@))usb:
$(MAKE) -C drivers/usb$(SUBDIRS):
$(MAKE) -C $@ all

ALL = $(obj)u-boot.srec $(obj)u-boot.bin $(obj)System.map $(U_BOOT_NAND)all: $(ALL)$(obj)u-boot.hex: $(obj)u-boot
$(OBJCOPY) ${OBJCFLAGS} -O ihex $< $@$(obj)u-boot.srec: $(obj)u-boot
$(OBJCOPY) ${OBJCFLAGS} -O srec $< $@$(obj)u-boot.bin: $(obj)u-boot
$(OBJCOPY) ${OBJCFLAGS} -O binary $< $@$(obj)u-boot.img: $(obj)u-boot.bin
./tools/mkimage -A $(ARCH) -T firmware -C none \
-a $(TEXT_BASE) -e \
-n $(shell sed -n -e 's/.*U_BOOT_VERSION//p' $(VERSION_FILE) | \
sed -e 's/"[ ]*$$/ for $(BOARD) board"/') \
-d $< $@$(obj)u-boot.dis: $(obj)u-boot
$(OBJDUMP) -d $< > $@$(obj)u-boot: depend version $(SUBDIRS) $(OBJS) $(LIBS) $(LDSCRIPT)
UNDEF_SYM=`$(OBJDUMP) -x $(LIBS) |sed -n -e 's/.*\(__u_boot_cmd_.*\)/-u\1/p'|sort|uniq`;\
cd $(LNDIR) && $(LD) $(LDFLAGS) $$UNDEF_SYM $(__OBJS) \
--start-group $(__LIBS) --end-group $(PLATFORM_LIBS) \
-Map u-boot.map -o u-boot

SECTIONS
{
. = 0x00000000; . = ALIGN();
.text :
{
cpu/arm920t/start.o (.text)
board/CCJ/boot_init.o (.text)
*(.text)
} . = ALIGN();
.rodata : { *(.rodata) } . = ALIGN();
.data : { *(.data) } . = ALIGN();
.got : { *(.got) } . = .;
__u_boot_cmd_start = .;
.u_boot_cmd : { *(.u_boot_cmd) }
__u_boot_cmd_end = .; . = ALIGN();
__bss_start = .;
.bss : { *(.bss) }
_end = .;
}