201106rc3uboot的mkconfig注释
201106rc3uboot的mkconfig注释
#make smdk2410_config 在Makefile中实际调用了$(CURDIR)/mkconfig -A smdk2410
#两个参数 $1为-A $2为smdk2410
#!/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) 2002-2010 DENX Software Engineering, Wolfgang Denk <[email protected]>
#
APPEND=no # Default: Create new config file
BOARD_NAME="" # Name to print in make output
TARGETS=""
arch=""
cpu=""
board=""
vendor=""
soc=""
options=""
#参数数量==2 并且 参数1==-A 所以make smdk2410_config进入
if [ \( $# -eq 2 \) -a \( "$1" = "-A" \) ] ; then
# Automatic mode
#在boards.cfg不区分大小写，查找smdk2410开头的行，赋值给line
#line==smdk2410 arm arm920t - samsung s3c24x0
line=`egrep -i "^[[:space:]]*${2}[[:space:]]" boards.cfg` || {
echo "make: *** No rule to make target \`$2_config''. Stop." >&2
exit 1
}
#设置$1=smdk2410 $2=arm $3=arm920t $4=- $5=samsung $6=s3c24x0 and $#=6
set ${line}
# add default board name if needed
#[ $# = 3 ]不成立，不执行set ${line} ${1}
[ $# = 3 ] && set ${line} ${1}
fi
#$#=6>0,进入循环 实际上命令make smdk2410_config变成$(CURDIR)/mkconfig smdk2410 arm arm920t - samsung s3c24x0
#$1=smdk2410 所以直接break
while [ $# -gt 0 ] ; do
case "$1" in
--) shift ; break ;;
-a) shift ; APPEND=yes ;;
-n) shift ; BOARD_NAME="${1%_config}" ; shift ;;
-t) shift ; TARGETS="`echo $1 | sed ''s:_: :g''` ${TARGETS}" ; shift ;;
*) break ;;
esac
done
#以下两行都不成立，不退出
[ $# -lt 4 ] && exit 1
[ $# -gt 7 ] && exit 1
# Strip all options and/or _config suffixes
#smdk2410没有匹配_config的字符串，不用去掉，所以CONFIG_NAME="smdk2410"
CONFIG_NAME="${1%_config}"
#BOARD_NAME="smdk2410"
[ "${BOARD_NAME}" ] || BOARD_NAME="${1%_config}"
#arch="arm"
arch="$2"
#cpu="arm920t"
cpu="$3"
#board="smdk2410"
if [ "$4" = "-" ] ; then
board=${BOARD_NAME}
else
board="$4"
fi
#vendor="samsung"
[ $# -gt 4 ] && [ "$5" != "-" ] && vendor="$5"
#soc="s3c24x0"
[ $# -gt 5 ] && [ "$6" != "-" ] && soc="$6"
#[ $# -gt 6 ]不成立，不运行下面的
[ $# -gt 6 ] && [ "$7" != "-" ] && {
# check if we have a board config name in the options field
# the options field mave have a board config name and a list
# of options, both separated by a colon ('':''); the options are
# separated by commas ('','').
#
# Check for board name
tmp="${7%:*}"
if [ "$tmp" ] ; then
CONFIG_NAME="$tmp"
fi
# Check if we only have a colon...
if [ "${tmp}" != "$7" ] ; then
options=${7#*:}
TARGETS="`echo ${options} | sed ''s:,: :g''` ${TARGETS}"
fi
}
#${ARCH}不存在，不进入
if [ "${ARCH}" -a "${ARCH}" != "${arch}" ]; then
echo "Failed: \$ARCH=${ARCH}, should be ''${arch}'' for ${BOARD_NAME}" 1>&2
exit 1
fi
#options为空，不进入，echo "Configuring for smdk2410 board..."
if [ "$options" ] ; then
echo "Configuring for ${BOARD_NAME} - Board: ${CONFIG_NAME}, Options: ${options}"
else
echo "Configuring for ${BOARD_NAME} board..."
fi
#
# Create link to architecture specific headers
#
#因为没有加入 O= ,所以$SRCTREE=$OBJTREE=$(CURDIR) $(CURDIR)是GNU MAKE的环境变量，值为当前文件夹绝对路径
if [ "$SRCTREE" != "$OBJTREE" ] ; then
mkdir -p ${OBJTREE}/include
mkdir -p ${OBJTREE}/include2
cd ${OBJTREE}/include2
rm -f asm
ln -s ${SRCTREE}/arch/${arch}/include/asm asm
LNPREFIX=${SRCTREE}/arch/${arch}/include/asm/
cd ../include
mkdir -p asm
else
#连接到目标平台的include/asm目录
cd ./include
rm -f asm #删除上次编译产生的asm软连接
ln -s ../arch/${arch}/include/asm asm
fi
#删除上次编译产生的asm/arch软连接
rm -f asm/arch
#${soc}="s3c24x0" 不为null，不进入
if [ -z "${soc}" ] ; then
ln -s ${LNPREFIX}arch-${cpu} asm/arch
else
#建立软连接include/asm/arch，连接到 arch/arm/include/asm/arch-s3c24x0 ${LNPREFIX}为空 注意连接的目标所在目录
ln -s ${LNPREFIX}arch-${soc} asm/arch
fi
#进入
if [ "${arch}" = "arm" ] ; then
#删除上次编译产生的asm/proc软连接
rm -f asm/proc
#建立软连接include/asm/proc，连接到 arch/arm/include/asm/proc-armv
ln -s ${LNPREFIX}proc-armv asm/proc
fi
#
# Create include file for Make
#
#在include/config.mk文件中加入5个变量
echo "ARCH = ${arch}" > config.mk
echo "CPU = ${cpu}" >> config.mk
echo "BOARD = ${board}" >> config.mk
[ "${vendor}" ] && echo "VENDOR = ${vendor}" >> config.mk
[ "${soc}" ] && echo "SOC = ${soc}" >> config.mk
# Assign board directory to BOARDIR variable
#${vendor}不为null，不进入
if [ -z "${vendor}" ] ; then
BOARDDIR=${board}
else
#BOARDDIR=samsung/smdk2410
BOARDDIR=${vendor}/${board}
fi
#
# Create board specific header file
#
//$APPEND = no ，不进入
if [ "$APPEND" = "yes" ] # Append to existing config file
then
echo >> config.h
else
#新建，以前内容删除
> config.h # Create new config file
fi
echo "/* Automatically generated - do not edit */" >>config.h
#${TARGETS}为空，for循环没执行
for i in ${TARGETS} ; do
i="`echo ${i} | sed ''/=/ {s/=/\t/;q } ; { s/$/\t1/ }''`"
echo "#define CONFIG_${i}" >>config.h ;
done
#cat追加内容进config.h
cat << EOF >> config.h
#define CONFIG_BOARDDIR board/$BOARDDIR
#include
#include
#include
#include
EOF