mini6410 uboot makefile 注释
2012-12-03 21:19
239 查看
首先来看顶层目录 Makefile 文件
VERSION = 1
PATCHLEVEL = 1
SUBLEVEL = 6
EXTRAVERSION =
U_BOOT_VERSION = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)
VERSION_FILE = $(obj)include/version_autogenerated.h
#uboot 版本号 1.1.6
HOSTARCH := $(shell uname -m | /
sed -e s/i.86/i386/ /
-e s/sun4u/sparc64/ /
-e s/arm.*/arm/ /
-e s/sa110/arm/ /
-e s/powerpc/ppc/ /
-e s/macppc/ppc/)
#HOSTARCH :=i386
#sed 用法 uname -m 输出 i686 sed 将i686 替换为 i386
HOSTOS := $(shell uname -s | tr '[:upper:]' '[:lower:]' | /
sed -e 's//(cygwin/).*/cygwin/')
# tr '[:upper:]' '[:lower:]' 把大写改为小写 即 Linux 改为 linux
#HOSTOS := linux
exportHOSTARCH HOSTOS
# HOSTARCH := i386
# HOSTOS := linux
#########################################################################
#
# U-boot build supports producing a object files to the separate external
# directory. Two use cases are supported:
#
# 1) Add O= to the make command line
# 'make O=/tmp/build all'
#
# 2) Set environement variable BUILD_DIR to point to the desired location
# 'export BUILD_DIR=/tmp/build'
# 'make'
#
# The second approach can also be used with a MAKEALL script
# 'export BUILD_DIR=/tmp/build'
# './MAKEALL'
#
# Command line 'O=' setting overrides BUILD_DIR environent variable.
#
# When none of the above methods is used the local build is performed and
# the object files are placed in the source directory.
#
ifdef O
ifeq ("$(origin O)", "command line")
#origin函数用于查询变量的出处，此处期望他在命令行中定义
BUILD_DIR := $(O)
endif
endif
ifneq ($(BUILD_DIR),)
saved-output := $(BUILD_DIR)
#如果BUILD_DIR 不为空
# Attempt to create a output directory.
$(shell [ -d ${BUILD_DIR} ] || mkdir -p ${BUILD_DIR})
# Verify if it was successful.
BUILD_DIR := $(shell cd $(BUILD_DIR) && /bin/pwd)
$(if $(BUILD_DIR),,$(error output directory "$(saved-output)" does not exist))
endif # ifneq ($(BUILD_DIR),)
# BUILD_DIR
是否存在
OBJTREE:= $(if $(BUILD_DIR),$(BUILD_DIR),$(CURDIR))
#****当BUILD_DIR存在时则赋给OBJTREE，否则OBJTREE=CURDIR（它代表当前工作目录，应该是个环境变量）
SRCTREE:= $(CURDIR)
TOPDIR:= $(SRCTREE)
LNDIR:= $(OBJTREE)
exportTOPDIR SRCTREE OBJTREE
MKCONFIG:= $(SRCTREE)/mkconfig
export MKCONFIG
#MKCONFIG
：= mkconfig
#****这个脚本文件很重要
ifneq ($(OBJTREE),$(SRCTREE))
REMOTE_BUILD:= 1
export REMOTE_BUILD
endif
#****建立外部目录的部分就结束了
# $(obj) and (src) are defined in config.mk but here in main Makefile
# we also need them before config.mk is included which is the case for
# some targets like unconfig, clean, clobber, distclean, etc.
ifneq ($(OBJTREE),$(SRCTREE))
obj := $(OBJTREE)/
src := $(SRCTREE)/
else
obj :=
src :=
endif
export obj src
#########################################################################
#########################################################################
ifeq ($(OBJTREE)/include/config.mk,$(wildcard $(OBJTREE)/include/config.mk))
# load ARCH, BOARD, and CPU configuration
include $(OBJTREE)/include/config.mk
exportARCH CPU BOARD VENDOR SOC
#/include/config.mk 内容 在make *_config 时产生
#
# 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 = $6" >> config.mk
#ARCH = arm
#CPU = s3c64xx
#BOARD = mini6410
#VENDOR = samsung
#SOC = s3c6410
ifeq ($(ARCH),arm)
CROSS_COMPILE = arm-linux-
endif
CROSS_COMPILE = arm-linux-
exportCROSS_COMPILE
#指定交叉编译工具前缀
# load other configuration
include $(TOPDIR)/config.mk
****重要的配置脚本总结：
$(SRCTREE)/mkconfig
$(TOPDIR)/config.mk
$(obj)include/config.mk
注意前面两个是在源文件目录，而后两个在目标文件目录，当然他们也可能一样
#########################################################################
# U-Boot objects....order is important (i.e. start must be first)
OBJS = cpu/$(CPU)/start.o
OBJS := $(addprefix $(obj),$(OBJS))
#addprefix加前缀函数
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 fs/jffs2/libjffs2.a /
fs/reiserfs/libreiserfs.a fs/ext2/libext2fs.a
LIBS += net/libnet.a
LIBS += disk/libdisk.a
LIBS += rtc/librtc.a
LIBS += dtt/libdtt.a
LIBS += drivers/libdrivers.a
LIBS += drivers/nand/libnand.a
LIBS += drivers/nand_legacy/libnand_legacy.a
# add to support onenand. by scsuh
LIBS += drivers/onenand/libonenand.a
LIBS += drivers/sk98lin/libsk98lin.a
LIBS += post/libpost.a post/cpu/libcpu.a
LIBS += common/libcommon.a
LIBS += $(BOARDLIBS)
LIBS := $(addprefix $(obj),$(LIBS))
****LIBS,包含了后缀为.a的文件，这种文件是在进到到各个目录执行make产生的库文件，链接时需要这些文件。链接的文件涉及到了
lib_generic目录,cpu目录，lib_arm目录（以arm为例子），fs目录，net目录，disk目录，drivers目录。从上面这段代码就可以清楚的知道，整个u-boot究竟需要什么文件，由哪些文件组成。
.PHONY : $(LIBS)
****声明伪目标，在后面的编译中用
# Add GCC lib
PLATFORM_LIBS += -L $(shell dirname `$(CC) $(CFLAGS) -print-libgcc-file-name`) -lgcc
#dirname
去掉最后一层目录
#CC=
$(CROSS_COMPILE)gcc = arm-linux-gcc
CFLAGS
编译选项，也是在顶层目录的config.mk中定义
# The "tools" are needed early, so put this first
# Don't include stuff already done in $(LIBS)
SUBDIRS= tools /
examples /
post /
post/cpu
.PHONY : $(SUBDIRS)
#伪目标SUBDIRS:
执行tools ,examples ,post,post/cpu
子目录下面的make文件
ifeq ($(CONFIG_NAND_U_BOOT),y)
NAND_SPL = nand_spl
U_BOOT_NAND = $(obj)u-boot-nand.bin
endif
__OBJS := $(subst $(obj),,$(OBJS))
#去掉前缀，__OBJS=cpu/arm920t/start.o
__LIBS := $(subst $(obj),,$(LIBS))
#去掉前缀，__LIBS=$(LIBS)+$(LIBBOARD)
#########################################################################
ALL = $(obj)u-boot.srec $(obj)u-boot.bin $(obj)System.map $(U_BOOT_NAND)
all:$(ALL)
****当输入命令
make all,讲寻找到此次的伪目标all，all依赖于
$(ALL),ALL由4部分组成。那么接下去就分别对这4部分进行递归的处理。
$(obj)u-boot.hex:$(obj)u-boot
$(OBJCOPY) ${OBJCFLAGS} -O ihex $< $@
#arm-linux-objcopy被用来复制一个目标文件的内容到另一个文件中,
#可用于不同源文件的之间的格式转换
#OBJCOPY = $(CROSS_COMPILE)objcopy
$(obj)u-boot.srec:$(obj)u-boot
$(OBJCOPY) ${OBJCFLAGS} -O srec $< $@
$(obj)u-boot.bin:$(obj)u-boot
$(OBJCOPY) ${OBJCFLAGS} -O binary $< $@
$(OBJDUMP) -d $< > $<.dis
（1）目标文件u-boot.bin依赖于
$(obj)u-boot目标；
$(obj)u-boot:depend
version $(SUBDIRS) $(OBJS) $(LIBS) $(LDSCRIPT)
（1.1.1）depend：执行的操作为：进入到$(SUBDIRS)，生成各个子目录的.depend文件。通过调用各个子目录的make
_depend。
depend dep:
for dir in $(SUBDIRS) ; do $(MAKE) -C $$dir _depend ; done
（1.1.2）$(SUBDIRS)；执行操作为：对各个子目录执行makefile文件。
$(SUBDIRS):
$(MAKE) -C $@ all
(1.1.3) $(OBJS);执行：
$(MAKE) -C cpu/$(CPU) $(if $(REMOTE_BUILD),$@,$(notdir $@))
如果cpu为arm920t，编译文件cpu/arm920t。
(1.1.4) $(LIBS) ;依赖$(SUBDIRS).执行操作为：
$(MAKE) -C $(dir $(subst $(obj),,$@))，
dir为GNU内嵌函数为取目录操作，比如$(dir a/b/c)
结果为
a/b/;subst
也是GNU内嵌函数$(subst from,to,text)表示在text
中把form 字符串替换为字符串to。subst资料上面是这样讲的。但是
在此处，我认为是：$(subst text，
to，
from)。总之，这样理解
吧：在LIBS包含的n个路径下面执行make
$(obj)u-boot.img:$(obj)u-boot.bin
./tools/mkimage -A $(ARCH) -T firmware -C none /
-a $(TEXT_BASE) -e 0 /
-n $(shell sed -n -e 's/.*U_BOOT_VERSION//p' $(VERSION_FILE) | /
sed -e 's/"[ ]*$$/ 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) $$UNDEF_SYM $(__OBJS) /
--start-group $(__LIBS) --end-group $(PLATFORM_LIBS) /
-Map u-boot.map -o u-boot
#LNDIR:=
$(OBJTREE)
#LD=
$(CROSS_COMPILE)ld
$(OBJS):
$(MAKE) -C cpu/$(CPU) $(if $(REMOTE_BUILD),$@,$(notdir $@))
$(LIBS):
$(MAKE) -C $(dir $(subst $(obj),,$@))
$(SUBDIRS):
$(MAKE) -C $@ all
$(NAND_SPL):version
$(MAKE) -C nand_spl/board/$(BOARDDIR) all
$(U_BOOT_NAND):$(NAND_SPL) $(obj)u-boot.bin
cat $(obj)nand_spl/u-boot-spl-16k.bin $(obj)u-boot.bin > $(obj)u-boot-nand.bin
version:
@echo -n "#define U_BOOT_VERSION /"U-Boot " > $(VERSION_FILE); /
echo -n "$(U_BOOT_VERSION)" >> $(VERSION_FILE); /
echo -n $(shell $(CONFIG_SHELL) $(TOPDIR)/tools/setlocalversion /
$(TOPDIR)) >> $(VERSION_FILE); /
echo "/"" >> $(VERSION_FILE)
gdbtools:
$(MAKE) -C tools/gdb all || exit 1
updater:
$(MAKE) -C tools/updater all || exit 1
env:
$(MAKE) -C tools/env all || exit 1
depend dep:
for dir in $(SUBDIRS) ; do $(MAKE) -C $$dir _depend ; done
tags ctags:
ctags -w -o $(OBJTREE)/ctags `find $(SUBDIRS) include /
lib_generic board/$(BOARDDIR) cpu/$(CPU) lib_$(ARCH) /
fs/cramfs fs/fat fs/fdos fs/jffs2 /
net disk rtc dtt drivers drivers/sk98lin common /
/( -name CVS -prune /) -o /( -name '*.[ch]' -print /)`
etags:
etags -a -o $(OBJTREE)/etags `find $(SUBDIRS) include /
lib_generic board/$(BOARDDIR) cpu/$(CPU) lib_$(ARCH) /
fs/cramfs fs/fat fs/fdos fs/jffs2 /
net disk rtc dtt drivers drivers/sk98lin common /
/( -name CVS -prune /) -o /( -name '*.[ch]' -print /)`
$(obj)System.map:$(obj)u-boot
@$(NM) $< | /
grep -v '/(compiled/)/|/(/.o$$/)/|/( [aUw] /)/|/(/./.ng$$/)/|/(LASH[RL]DI/)' | /
sort > $(obj)System.map
#########################################################################
else
all $(obj)u-boot.hex $(obj)u-boot.srec $(obj)u-boot.bin /
$(obj)u-boot.img $(obj)u-boot.dis $(obj)u-boot /
$(SUBDIRS) version gdbtools updater env depend /
dep tags ctags etags $(obj)System.map:
@echo "System not configured - see README" >&2
@ exit 1
endif
.PHONY : CHANGELOG
CHANGELOG:
git log --no-merges U-Boot-1_1_5.. | /
unexpand -a | sed -e 's//s/s*$$//' > $@
#########################################################################
unconfig:
@rm -f $(obj)include/config.h $(obj)include/config.mk /
$(obj)board/*/config.tmp $(obj)board/*/*/config.tmp
#========================================================================
mini6410_nand_config-ram128 : unconfig
@$(MKCONFIG) mini6410 arm s3c64xx mini6410 samsung s3c6410 NAND ram128
unconfig:
@rm -f $(obj)include/config.h $(obj)include/config.mk /
$(obj)board/*/config.tmp $(obj)board/*/*/config.tmp
MKCONFIG:=
$(SRCTREE)/mkconfig
在执行make之前，我们先执行了make
*_config
例如我们执行
mini6410_nand_config-ram128 配置mini6410开发板 实际执行：
@$(MKCONFIG) mini6410 arm s3c64xx mini6410 samsung s3c6410 NAND ram128
$(MKCONFIG)
实际就是uboot顶层目录下的
mkconfig脚本文件，内容如下所示：
#!/bin/sh -e
# Script to create header files and links to configure
# U-Boot for a specific board.
#
# Parameters: Target Architecture CPU Board [VENDOR] [SOC]
#
# (C) 2002-2006 DENX Software Engineering, Wolfgang Denk <wd@denx.de>
#
APPEND=no# Default: Create new config file
BOARD_NAME=""# Name to print in make output
while [ $# -gt 0 ] ; 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 4 ] && exit 1
[ $# -gt 8 ] && exit 1
echo "Configuring for ${BOARD_NAME} board which boot from $7 $8..."
#
# Create link to architecture specific headers
#
if [ "$SRCTREE" != "$OBJTREE" ] ; then
mkdir -p ${OBJTREE}/include
mkdir -p ${OBJTREE}/include2
cd ${OBJTREE}/include2
rm -f asm
ln -s ${SRCTREE}/include/asm-$2 asm
LNPREFIX="../../include2/asm/"
cd ../include
rm -rf asm-$2
rm -f asm
mkdir asm-$2
ln -s asm-$2 asm
else
cd ./include
rm -f asm
ln -s asm-$2 asm //建立从asm-arm
到 asm的链接
fi
rm -f asm-$2/arch
if [ -z "$6" -o "$6" = "NULL" ] ; then
ln -s ${LNPREFIX}arch-$3 asm-$2/arch
else
ln -s ${LNPREFIX}arch-$6 asm-$2/arch
fi
@$(MKCONFIG)
$1、mini6410 $2、arm
$3、s3c64xx $4、mini6410 $5、samsung
$6、s3c6410 $7、NAND $8、ram128
# create link for s3c64xx SoC
if [ "$3" = "s3c64xx" ] ; then
rm -f regs.h
ln -s $6.h regs.h
rm -f asm-$2/arch
ln -s arch-$3 asm-$2/arch
fi
if [ "$2" = "arm" ] ; then
rm -f asm-$2/proc
ln -s ${LNPREFIX}proc-armv asm-$2/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
case $7 in
SD)
echo "#define FRIENDLYARM_BOOT_MEDIA_SD" >> config.h
;;
NAND)
echo "#define FRIENDLYARM_BOOT_MEDIA_NAND" >> config.h
;;
*)
;;
esac
case $8 in
ram128)
echo "#define FRIENDLYARM_BOOT_RAM128" >> config.h
;;
ram256)
echo "#define FRIENDLYARM_BOOT_RAM256" >> config.h
;;
*)
;;
esac
echo "#include <configs/$1.h>" >>config.h
exit 0
下面分析 config.mk 这个文件的作用等于 kernel 中的 .config ？
#
# (C) Copyright 2000-2006
# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
#
# See file CREDITS for list of people who contributed to this
# project.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of
# the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
# MA 02111-1307 USA
#
#########################################################################
ifneq ($(OBJTREE),$(SRCTREE))
ifeq ($(CURDIR),$(SRCTREE))
dir :=
else
dir := $(subst $(SRCTREE)/,,$(CURDIR))
endif
obj := $(if $(dir),$(OBJTREE)/$(dir)/,$(OBJTREE)/)
src := $(if $(dir),$(SRCTREE)/$(dir)/,$(SRCTREE)/)
$(shell mkdir -p $(obj))
else
obj :=
src :=
endif
# clean the slate ...
PLATFORM_RELFLAGS =
PLATFORM_CPPFLAGS =
PLATFORM_LDFLAGS =
#
# When cross-compiling on NetBSD, we have to define __PPC__ or else we
# will pick up a va_list declaration that is incompatible with the
# actual argument lists emitted by the compiler.
#
# [Tested on NetBSD/i386 1.5 + cross-powerpc-netbsd-1.3]
ifdefARCH
sinclude $(TOPDIR)/$(ARCH)_config.mk# include
architecture dependend rules
endif
ifdefCPU
sinclude $(TOPDIR)/cpu/$(CPU)/config.mk#
include CPUspecific rules
endif
ifdefSOC
sinclude $(TOPDIR)/cpu/$(CPU)/$(SOC)/config.mk#
include SoCspecific rules
endif
ifdefVENDOR
BOARDDIR = $(VENDOR)/$(BOARD)
else
BOARDDIR = $(BOARD)
endif
ifdefBOARD
sinclude $(TOPDIR)/board/$(BOARDDIR)/config.mk#
include board specific rules
endif
#config.mk 内容
#ifndef TEXT_BASE
#TEXT_BASE = 0xc7e00000
#endif
#########################################################################
CONFIG_SHELL:= $(shell if [ -x "$$BASH"
]; then echo $$BASH; /
else if [ -x /bin/bash ]; then echo /bin/bash; /
else echo sh; fi ; fi)
ifeq ($(HOSTOS)-$(HOSTARCH),darwin-ppc)
HOSTCC= cc
else
HOSTCC= gcc
endif
HOSTCFLAGS= -Wall -Wstrict-prototypes -O2
-fomit-frame-pointer
HOSTSTRIP= strip
#########################################################################
#
# Option checker (courtesy linux kernel) to ensure
# only supported compiler options are used
#
cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null /
> /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
#
# Include the make variables (CC, etc...)
#
AS= $(CROSS_COMPILE)as
LD= $(CROSS_COMPILE)ld
CC= $(CROSS_COMPILE)gcc
CPP= $(CC) -E
AR= $(CROSS_COMPILE)ar
NM= $(CROSS_COMPILE)nm
STRIP= $(CROSS_COMPILE)strip
OBJCOPY = $(CROSS_COMPILE)objcopy
OBJDUMP = $(CROSS_COMPILE)objdump
RANLIB= $(CROSS_COMPILE)RANLIB
＠定义AR选项ARFLAGS，调试选项DBGFLAGS，优化选项OPTFLAGS
预处理选项CPPFLAGS，C编译器选项CFLAGS，连接选项LDFLAGS
ifneq (,$(findstring s,$(MAKEFLAGS)))
ARFLAGS = cr
else
ARFLAGS = crv
endif
RELFLAGS= $(PLATFORM_RELFLAGS)
DBGFLAGS= -g # -DDEBUG
OPTFLAGS= -Os #-fomit-frame-pointer
ifndef LDSCRIPT
#LDSCRIPT := $(TOPDIR)/board/$(BOARDDIR)/u-boot.lds.debug
ifeq ($(CONFIG_NAND_U_BOOT),y)
LDSCRIPT := $(TOPDIR)/board/$(BOARDDIR)/u-boot-nand.lds
else
LDSCRIPT := $(TOPDIR)/board/$(BOARDDIR)/u-boot.lds
endif
endif
OBJCFLAGS += --gap-fill=0xff
gccincdir := $(shell $(CC) -print-file-name=include)
CPPFLAGS := $(DBGFLAGS) $(OPTFLAGS) $(RELFLAGS)/
-D__KERNEL__ -DTEXT_BASE=$(TEXT_BASE)/
ifneq ($(OBJTREE),$(SRCTREE))
CPPFLAGS += -I$(OBJTREE)/include2 -I$(OBJTREE)/include
endif
CPPFLAGS += -I$(TOPDIR)/include
CPPFLAGS += -fno-builtin -ffreestanding -nostdinc
/
-isystem $(gccincdir) -pipe $(PLATFORM_CPPFLAGS)
ifdef BUILD_TAG
CFLAGS := $(CPPFLAGS) -Wall -Wstrict-prototypes /
-DBUILD_TAG='"$(BUILD_TAG)"'
else
CFLAGS := $(CPPFLAGS) -Wall -Wstrict-prototypes
endif
# $(CPPFLAGS) sets -g, which causes gcc to pass a suitable -g<format>
# option to the assembler.
AFLAGS_DEBUG :=
AFLAGS := $(AFLAGS_DEBUG) -D__ASSEMBLY__ $(CPPFLAGS)
LDFLAGS += -Bstatic -T $(LDSCRIPT) -Ttext $(TEXT_BASE) $(PLATFORM_LDFLAGS)
# Location of a usable BFD library, where we define "usable" as
# "built for ${HOST}, supports ${TARGET}". Sensible values are
# - When cross-compiling: the root of the cross-environment
# - Linux/ppc (native): /usr
# - NetBSD/ppc (native): you lose ... (must extract these from the
# binutils build directory, plus the native and U-Boot include
# files don't like each other)
#
# So far, this is used only by tools/gdb/Makefile.
ifeq ($(HOSTOS)-$(HOSTARCH),darwin-ppc)
BFD_ROOT_DIR =/usr/local/tools
else
ifeq ($(HOSTARCH),$(ARCH))
# native
BFD_ROOT_DIR =/usr
else
#BFD_ROOT_DIR =/LinuxPPC/CDK#
Linux/i386
#BFD_ROOT_DIR =/usr/pkg/cross#
NetBSD/i386
BFD_ROOT_DIR =/opt/powerpc
endif
endif
ifeq ($(PCI_CLOCK),PCI_66M)
CFLAGS := $(CFLAGS) -DPCI_66M
endif
#########################################################################
exportCONFIG_SHELL HPATH HOSTCC HOSTCFLAGS
CROSS_COMPILE /
AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP /
MAKE
exportTEXT_BASE PLATFORM_CPPFLAGS PLATFORM_RELFLAGS
CPPFLAGS CFLAGS AFLAGS
#########################################################################
ifndef REMOTE_BUILD
%.s:%.S
$(CPP) $(AFLAGS) -o $@ $<
%.o:%.S
$(CC) $(AFLAGS) -c -o $@ $<
%.o:%.c
$(CC) $(CFLAGS) -c -o $@ $<
else
$(obj)%.s:%.S
$(CPP) $(AFLAGS) -o $@ $<
$(obj)%.o:%.S
$(CC) $(AFLAGS) -c -o $@ $<
$(obj)%.o:%.c
$(CC) $(CFLAGS) -c -o $@ $<
endif
#########################################################################
VERSION = 1
PATCHLEVEL = 1
SUBLEVEL = 6
EXTRAVERSION =
U_BOOT_VERSION = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)
VERSION_FILE = $(obj)include/version_autogenerated.h
#uboot 版本号 1.1.6
HOSTARCH := $(shell uname -m | /
sed -e s/i.86/i386/ /
-e s/sun4u/sparc64/ /
-e s/arm.*/arm/ /
-e s/sa110/arm/ /
-e s/powerpc/ppc/ /
-e s/macppc/ppc/)
#HOSTARCH :=i386
#sed 用法 uname -m 输出 i686 sed 将i686 替换为 i386
HOSTOS := $(shell uname -s | tr '[:upper:]' '[:lower:]' | /
sed -e 's//(cygwin/).*/cygwin/')
# tr '[:upper:]' '[:lower:]' 把大写改为小写 即 Linux 改为 linux
#HOSTOS := linux
exportHOSTARCH HOSTOS
# HOSTARCH := i386
# HOSTOS := linux
#########################################################################
#
# U-boot build supports producing a object files to the separate external
# directory. Two use cases are supported:
#
# 1) Add O= to the make command line
# 'make O=/tmp/build all'
#
# 2) Set environement variable BUILD_DIR to point to the desired location
# 'export BUILD_DIR=/tmp/build'
# 'make'
#
# The second approach can also be used with a MAKEALL script
# 'export BUILD_DIR=/tmp/build'
# './MAKEALL'
#
# Command line 'O=' setting overrides BUILD_DIR environent variable.
#
# When none of the above methods is used the local build is performed and
# the object files are placed in the source directory.
#
ifdef O
ifeq ("$(origin O)", "command line")
#origin函数用于查询变量的出处，此处期望他在命令行中定义
BUILD_DIR := $(O)
endif
endif
ifneq ($(BUILD_DIR),)
saved-output := $(BUILD_DIR)
#如果BUILD_DIR 不为空
# Attempt to create a output directory.
$(shell [ -d ${BUILD_DIR} ] || mkdir -p ${BUILD_DIR})
# Verify if it was successful.
BUILD_DIR := $(shell cd $(BUILD_DIR) && /bin/pwd)
$(if $(BUILD_DIR),,$(error output directory "$(saved-output)" does not exist))
endif # ifneq ($(BUILD_DIR),)
# BUILD_DIR
是否存在
OBJTREE:= $(if $(BUILD_DIR),$(BUILD_DIR),$(CURDIR))
#****当BUILD_DIR存在时则赋给OBJTREE，否则OBJTREE=CURDIR（它代表当前工作目录，应该是个环境变量）
SRCTREE:= $(CURDIR)
TOPDIR:= $(SRCTREE)
LNDIR:= $(OBJTREE)
exportTOPDIR SRCTREE OBJTREE
MKCONFIG:= $(SRCTREE)/mkconfig
export MKCONFIG
#MKCONFIG
：= mkconfig
#****这个脚本文件很重要
ifneq ($(OBJTREE),$(SRCTREE))
REMOTE_BUILD:= 1
export REMOTE_BUILD
endif
#****建立外部目录的部分就结束了
# $(obj) and (src) are defined in config.mk but here in main Makefile
# we also need them before config.mk is included which is the case for
# some targets like unconfig, clean, clobber, distclean, etc.
ifneq ($(OBJTREE),$(SRCTREE))
obj := $(OBJTREE)/
src := $(SRCTREE)/
else
obj :=
src :=
endif
export obj src
#########################################################################
#########################################################################
ifeq ($(OBJTREE)/include/config.mk,$(wildcard $(OBJTREE)/include/config.mk))
# load ARCH, BOARD, and CPU configuration
include $(OBJTREE)/include/config.mk
exportARCH CPU BOARD VENDOR SOC
#/include/config.mk 内容 在make *_config 时产生
#
# 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
#ARCH = arm
#CPU = s3c64xx
#BOARD = mini6410
#VENDOR = samsung
#SOC = s3c6410
ifeq ($(ARCH),arm)
CROSS_COMPILE = arm-linux-
endif
CROSS_COMPILE = arm-linux-
exportCROSS_COMPILE
#指定交叉编译工具前缀
# load other configuration
include $(TOPDIR)/config.mk
****重要的配置脚本总结：
$(SRCTREE)/mkconfig
$(TOPDIR)/config.mk
$(obj)include/config.mk
注意前面两个是在源文件目录，而后两个在目标文件目录，当然他们也可能一样
#########################################################################
# U-Boot objects....order is important (i.e. start must be first)
OBJS = cpu/$(CPU)/start.o
OBJS := $(addprefix $(obj),$(OBJS))
#addprefix加前缀函数
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 fs/jffs2/libjffs2.a /
fs/reiserfs/libreiserfs.a fs/ext2/libext2fs.a
LIBS += net/libnet.a
LIBS += disk/libdisk.a
LIBS += rtc/librtc.a
LIBS += dtt/libdtt.a
LIBS += drivers/libdrivers.a
LIBS += drivers/nand/libnand.a
LIBS += drivers/nand_legacy/libnand_legacy.a
# add to support onenand. by scsuh
LIBS += drivers/onenand/libonenand.a
LIBS += drivers/sk98lin/libsk98lin.a
LIBS += post/libpost.a post/cpu/libcpu.a
LIBS += common/libcommon.a
LIBS += $(BOARDLIBS)
LIBS := $(addprefix $(obj),$(LIBS))
****LIBS,包含了后缀为.a的文件，这种文件是在进到到各个目录执行make产生的库文件，链接时需要这些文件。链接的文件涉及到了
lib_generic目录,cpu目录，lib_arm目录（以arm为例子），fs目录，net目录，disk目录，drivers目录。从上面这段代码就可以清楚的知道，整个u-boot究竟需要什么文件，由哪些文件组成。
.PHONY : $(LIBS)
****声明伪目标，在后面的编译中用
# Add GCC lib
PLATFORM_LIBS += -L $(shell dirname `$(CC) $(CFLAGS) -print-libgcc-file-name`) -lgcc
#dirname
去掉最后一层目录
#CC=
$(CROSS_COMPILE)gcc = arm-linux-gcc
CFLAGS
编译选项，也是在顶层目录的config.mk中定义
# The "tools" are needed early, so put this first
# Don't include stuff already done in $(LIBS)
SUBDIRS= tools /
examples /
post /
post/cpu
.PHONY : $(SUBDIRS)
#伪目标SUBDIRS:
执行tools ,examples ,post,post/cpu
子目录下面的make文件
ifeq ($(CONFIG_NAND_U_BOOT),y)
NAND_SPL = nand_spl
U_BOOT_NAND = $(obj)u-boot-nand.bin
endif
__OBJS := $(subst $(obj),,$(OBJS))
#去掉前缀，__OBJS=cpu/arm920t/start.o
__LIBS := $(subst $(obj),,$(LIBS))
#去掉前缀，__LIBS=$(LIBS)+$(LIBBOARD)
#########################################################################
ALL = $(obj)u-boot.srec $(obj)u-boot.bin $(obj)System.map $(U_BOOT_NAND)
all:$(ALL)
****当输入命令
make all,讲寻找到此次的伪目标all，all依赖于
$(ALL),ALL由4部分组成。那么接下去就分别对这4部分进行递归的处理。
$(obj)u-boot.hex:$(obj)u-boot
$(OBJCOPY) ${OBJCFLAGS} -O ihex $< $@
#arm-linux-objcopy被用来复制一个目标文件的内容到另一个文件中,
#可用于不同源文件的之间的格式转换
#OBJCOPY = $(CROSS_COMPILE)objcopy
$(obj)u-boot.srec:$(obj)u-boot
$(OBJCOPY) ${OBJCFLAGS} -O srec $< $@
$(obj)u-boot.bin:$(obj)u-boot
$(OBJCOPY) ${OBJCFLAGS} -O binary $< $@
$(OBJDUMP) -d $< > $<.dis
（1）目标文件u-boot.bin依赖于
$(obj)u-boot目标；
$(obj)u-boot:depend
version $(SUBDIRS) $(OBJS) $(LIBS) $(LDSCRIPT)
（1.1.1）depend：执行的操作为：进入到$(SUBDIRS)，生成各个子目录的.depend文件。通过调用各个子目录的make
_depend。
depend dep:
for dir in $(SUBDIRS) ; do $(MAKE) -C $$dir _depend ; done
（1.1.2）$(SUBDIRS)；执行操作为：对各个子目录执行makefile文件。
$(SUBDIRS):
$(MAKE) -C $@ all
(1.1.3) $(OBJS);执行：
$(MAKE) -C cpu/$(CPU) $(if $(REMOTE_BUILD),$@,$(notdir $@))
如果cpu为arm920t，编译文件cpu/arm920t。
(1.1.4) $(LIBS) ;依赖$(SUBDIRS).执行操作为：
$(MAKE) -C $(dir $(subst $(obj),,$@))，
dir为GNU内嵌函数为取目录操作，比如$(dir a/b/c)
结果为
a/b/;subst
也是GNU内嵌函数$(subst from,to,text)表示在text
中把form 字符串替换为字符串to。subst资料上面是这样讲的。但是
在此处，我认为是：$(subst text，
to，
from)。总之，这样理解
吧：在LIBS包含的n个路径下面执行make
$(obj)u-boot.img:$(obj)u-boot.bin
./tools/mkimage -A $(ARCH) -T firmware -C none /
-a $(TEXT_BASE) -e 0 /
-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
#LNDIR:=
$(OBJTREE)
#LD=
$(CROSS_COMPILE)ld
$(OBJS):
$(MAKE) -C cpu/$(CPU) $(if $(REMOTE_BUILD),$@,$(notdir $@))
$(LIBS):
$(MAKE) -C $(dir $(subst $(obj),,$@))
$(SUBDIRS):
$(MAKE) -C $@ all
$(NAND_SPL):version
$(MAKE) -C nand_spl/board/$(BOARDDIR) all
$(U_BOOT_NAND):$(NAND_SPL) $(obj)u-boot.bin
cat $(obj)nand_spl/u-boot-spl-16k.bin $(obj)u-boot.bin > $(obj)u-boot-nand.bin
version:
@echo -n "#define U_BOOT_VERSION /"U-Boot " > $(VERSION_FILE); /
echo -n "$(U_BOOT_VERSION)" >> $(VERSION_FILE); /
echo -n $(shell $(CONFIG_SHELL) $(TOPDIR)/tools/setlocalversion /
$(TOPDIR)) >> $(VERSION_FILE); /
echo "/"" >> $(VERSION_FILE)
gdbtools:
$(MAKE) -C tools/gdb all || exit 1
updater:
$(MAKE) -C tools/updater all || exit 1
env:
$(MAKE) -C tools/env all || exit 1
depend dep:
for dir in $(SUBDIRS) ; do $(MAKE) -C $$dir _depend ; done
tags ctags:
ctags -w -o $(OBJTREE)/ctags `find $(SUBDIRS) include /
lib_generic board/$(BOARDDIR) cpu/$(CPU) lib_$(ARCH) /
fs/cramfs fs/fat fs/fdos fs/jffs2 /
net disk rtc dtt drivers drivers/sk98lin common /
/( -name CVS -prune /) -o /( -name '*.[ch]' -print /)`
etags:
etags -a -o $(OBJTREE)/etags `find $(SUBDIRS) include /
lib_generic board/$(BOARDDIR) cpu/$(CPU) lib_$(ARCH) /
fs/cramfs fs/fat fs/fdos fs/jffs2 /
net disk rtc dtt drivers drivers/sk98lin common /
/( -name CVS -prune /) -o /( -name '*.[ch]' -print /)`
$(obj)System.map:$(obj)u-boot
@$(NM) $< | /
grep -v '/(compiled/)/|/(/.o$$/)/|/( [aUw] /)/|/(/./.ng$$/)/|/(LASH[RL]DI/)' | /
sort > $(obj)System.map
#########################################################################
else
all $(obj)u-boot.hex $(obj)u-boot.srec $(obj)u-boot.bin /
$(obj)u-boot.img $(obj)u-boot.dis $(obj)u-boot /
$(SUBDIRS) version gdbtools updater env depend /
dep tags ctags etags $(obj)System.map:
@echo "System not configured - see README" >&2
@ exit 1
endif
.PHONY : CHANGELOG
CHANGELOG:
git log --no-merges U-Boot-1_1_5.. | /
unexpand -a | sed -e 's//s/s*$$//' > $@
#########################################################################
unconfig:
@rm -f $(obj)include/config.h $(obj)include/config.mk /
$(obj)board/*/config.tmp $(obj)board/*/*/config.tmp
#========================================================================
mini6410_nand_config-ram128 : unconfig
@$(MKCONFIG) mini6410 arm s3c64xx mini6410 samsung s3c6410 NAND ram128
unconfig:
@rm -f $(obj)include/config.h $(obj)include/config.mk /
$(obj)board/*/config.tmp $(obj)board/*/*/config.tmp
MKCONFIG:=
$(SRCTREE)/mkconfig
在执行make之前，我们先执行了make
*_config
例如我们执行
mini6410_nand_config-ram128 配置mini6410开发板 实际执行：
@$(MKCONFIG) mini6410 arm s3c64xx mini6410 samsung s3c6410 NAND ram128
$(MKCONFIG)
实际就是uboot顶层目录下的
mkconfig脚本文件，内容如下所示：
#!/bin/sh -e
# Script to create header files and links to configure
# U-Boot for a specific board.
#
# Parameters: Target Architecture CPU Board [VENDOR] [SOC]
#
# (C) 2002-2006 DENX Software Engineering, Wolfgang Denk <wd@denx.de>
#
APPEND=no# Default: Create new config file
BOARD_NAME=""# Name to print in make output
while [ $# -gt 0 ] ; 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 4 ] && exit 1
[ $# -gt 8 ] && exit 1
echo "Configuring for ${BOARD_NAME} board which boot from $7 $8..."
#
# Create link to architecture specific headers
#
if [ "$SRCTREE" != "$OBJTREE" ] ; then
mkdir -p ${OBJTREE}/include
mkdir -p ${OBJTREE}/include2
cd ${OBJTREE}/include2
rm -f asm
ln -s ${SRCTREE}/include/asm-$2 asm
LNPREFIX="../../include2/asm/"
cd ../include
rm -rf asm-$2
rm -f asm
mkdir asm-$2
ln -s asm-$2 asm
else
cd ./include
rm -f asm
ln -s asm-$2 asm //建立从asm-arm
到 asm的链接
fi
rm -f asm-$2/arch
if [ -z "$6" -o "$6" = "NULL" ] ; then
ln -s ${LNPREFIX}arch-$3 asm-$2/arch
else
ln -s ${LNPREFIX}arch-$6 asm-$2/arch
fi
@$(MKCONFIG)
$1、mini6410 $2、arm
$3、s3c64xx $4、mini6410 $5、samsung
$6、s3c6410 $7、NAND $8、ram128
# create link for s3c64xx SoC
if [ "$3" = "s3c64xx" ] ; then
rm -f regs.h
ln -s $6.h regs.h
rm -f asm-$2/arch
ln -s arch-$3 asm-$2/arch
fi
if [ "$2" = "arm" ] ; then
rm -f asm-$2/proc
ln -s ${LNPREFIX}proc-armv asm-$2/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
case $7 in
SD)
echo "#define FRIENDLYARM_BOOT_MEDIA_SD" >> config.h
;;
NAND)
echo "#define FRIENDLYARM_BOOT_MEDIA_NAND" >> config.h
;;
*)
;;
esac
case $8 in
ram128)
echo "#define FRIENDLYARM_BOOT_RAM128" >> config.h
;;
ram256)
echo "#define FRIENDLYARM_BOOT_RAM256" >> config.h
;;
*)
;;
esac
echo "#include <configs/$1.h>" >>config.h
exit 0
下面分析 config.mk 这个文件的作用等于 kernel 中的 .config ？
#
# (C) Copyright 2000-2006
# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
#
# See file CREDITS for list of people who contributed to this
# project.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of
# the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
# MA 02111-1307 USA
#
#########################################################################
ifneq ($(OBJTREE),$(SRCTREE))
ifeq ($(CURDIR),$(SRCTREE))
dir :=
else
dir := $(subst $(SRCTREE)/,,$(CURDIR))
endif
obj := $(if $(dir),$(OBJTREE)/$(dir)/,$(OBJTREE)/)
src := $(if $(dir),$(SRCTREE)/$(dir)/,$(SRCTREE)/)
$(shell mkdir -p $(obj))
else
obj :=
src :=
endif
# clean the slate ...
PLATFORM_RELFLAGS =
PLATFORM_CPPFLAGS =
PLATFORM_LDFLAGS =
#
# When cross-compiling on NetBSD, we have to define __PPC__ or else we
# will pick up a va_list declaration that is incompatible with the
# actual argument lists emitted by the compiler.
#
# [Tested on NetBSD/i386 1.5 + cross-powerpc-netbsd-1.3]
ifdefARCH
sinclude $(TOPDIR)/$(ARCH)_config.mk# include
architecture dependend rules
endif
ifdefCPU
sinclude $(TOPDIR)/cpu/$(CPU)/config.mk#
include CPUspecific rules
endif
ifdefSOC
sinclude $(TOPDIR)/cpu/$(CPU)/$(SOC)/config.mk#
include SoCspecific rules
endif
ifdefVENDOR
BOARDDIR = $(VENDOR)/$(BOARD)
else
BOARDDIR = $(BOARD)
endif
ifdefBOARD
sinclude $(TOPDIR)/board/$(BOARDDIR)/config.mk#
include board specific rules
endif
#config.mk 内容
#ifndef TEXT_BASE
#TEXT_BASE = 0xc7e00000
#endif
#########################################################################
CONFIG_SHELL:= $(shell if [ -x "$$BASH"
]; then echo $$BASH; /
else if [ -x /bin/bash ]; then echo /bin/bash; /
else echo sh; fi ; fi)
ifeq ($(HOSTOS)-$(HOSTARCH),darwin-ppc)
HOSTCC= cc
else
HOSTCC= gcc
endif
HOSTCFLAGS= -Wall -Wstrict-prototypes -O2
-fomit-frame-pointer
HOSTSTRIP= strip
#########################################################################
#
# Option checker (courtesy linux kernel) to ensure
# only supported compiler options are used
#
cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null /
> /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
#
# Include the make variables (CC, etc...)
#
AS= $(CROSS_COMPILE)as
LD= $(CROSS_COMPILE)ld
CC= $(CROSS_COMPILE)gcc
CPP= $(CC) -E
AR= $(CROSS_COMPILE)ar
NM= $(CROSS_COMPILE)nm
STRIP= $(CROSS_COMPILE)strip
OBJCOPY = $(CROSS_COMPILE)objcopy
OBJDUMP = $(CROSS_COMPILE)objdump
RANLIB= $(CROSS_COMPILE)RANLIB
＠定义AR选项ARFLAGS，调试选项DBGFLAGS，优化选项OPTFLAGS
预处理选项CPPFLAGS，C编译器选项CFLAGS，连接选项LDFLAGS
ifneq (,$(findstring s,$(MAKEFLAGS)))
ARFLAGS = cr
else
ARFLAGS = crv
endif
RELFLAGS= $(PLATFORM_RELFLAGS)
DBGFLAGS= -g # -DDEBUG
OPTFLAGS= -Os #-fomit-frame-pointer
ifndef LDSCRIPT
#LDSCRIPT := $(TOPDIR)/board/$(BOARDDIR)/u-boot.lds.debug
ifeq ($(CONFIG_NAND_U_BOOT),y)
LDSCRIPT := $(TOPDIR)/board/$(BOARDDIR)/u-boot-nand.lds
else
LDSCRIPT := $(TOPDIR)/board/$(BOARDDIR)/u-boot.lds
endif
endif
OBJCFLAGS += --gap-fill=0xff
gccincdir := $(shell $(CC) -print-file-name=include)
CPPFLAGS := $(DBGFLAGS) $(OPTFLAGS) $(RELFLAGS)/
-D__KERNEL__ -DTEXT_BASE=$(TEXT_BASE)/
ifneq ($(OBJTREE),$(SRCTREE))
CPPFLAGS += -I$(OBJTREE)/include2 -I$(OBJTREE)/include
endif
CPPFLAGS += -I$(TOPDIR)/include
CPPFLAGS += -fno-builtin -ffreestanding -nostdinc
/
-isystem $(gccincdir) -pipe $(PLATFORM_CPPFLAGS)
ifdef BUILD_TAG
CFLAGS := $(CPPFLAGS) -Wall -Wstrict-prototypes /
-DBUILD_TAG='"$(BUILD_TAG)"'
else
CFLAGS := $(CPPFLAGS) -Wall -Wstrict-prototypes
endif
# $(CPPFLAGS) sets -g, which causes gcc to pass a suitable -g<format>
# option to the assembler.
AFLAGS_DEBUG :=
AFLAGS := $(AFLAGS_DEBUG) -D__ASSEMBLY__ $(CPPFLAGS)
LDFLAGS += -Bstatic -T $(LDSCRIPT) -Ttext $(TEXT_BASE) $(PLATFORM_LDFLAGS)
# Location of a usable BFD library, where we define "usable" as
# "built for ${HOST}, supports ${TARGET}". Sensible values are
# - When cross-compiling: the root of the cross-environment
# - Linux/ppc (native): /usr
# - NetBSD/ppc (native): you lose ... (must extract these from the
# binutils build directory, plus the native and U-Boot include
# files don't like each other)
#
# So far, this is used only by tools/gdb/Makefile.
ifeq ($(HOSTOS)-$(HOSTARCH),darwin-ppc)
BFD_ROOT_DIR =/usr/local/tools
else
ifeq ($(HOSTARCH),$(ARCH))
# native
BFD_ROOT_DIR =/usr
else
#BFD_ROOT_DIR =/LinuxPPC/CDK#
Linux/i386
#BFD_ROOT_DIR =/usr/pkg/cross#
NetBSD/i386
BFD_ROOT_DIR =/opt/powerpc
endif
endif
ifeq ($(PCI_CLOCK),PCI_66M)
CFLAGS := $(CFLAGS) -DPCI_66M
endif
#########################################################################
exportCONFIG_SHELL HPATH HOSTCC HOSTCFLAGS
CROSS_COMPILE /
AS LD CC CPP AR NM STRIP OBJCOPY OBJDUMP /
MAKE
exportTEXT_BASE PLATFORM_CPPFLAGS PLATFORM_RELFLAGS
CPPFLAGS CFLAGS AFLAGS
#########################################################################
ifndef REMOTE_BUILD
%.s:%.S
$(CPP) $(AFLAGS) -o $@ $<
%.o:%.S
$(CC) $(AFLAGS) -c -o $@ $<
%.o:%.c
$(CC) $(CFLAGS) -c -o $@ $<
else
$(obj)%.s:%.S
$(CPP) $(AFLAGS) -o $@ $<
$(obj)%.o:%.S
$(CC) $(AFLAGS) -c -o $@ $<
$(obj)%.o:%.c
$(CC) $(CFLAGS) -c -o $@ $<
endif
#########################################################################
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