#!/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
在这里case中的break是退出while循环的，shell脚本中的case不需要break。
shift是循环将参数左移，先是移$1, 下次循环$2变为$1,$3变为$2
[ "${BOARD_NAME}" ] || BOARD_NAME="$1" //这是个简略的if语句，如果||前面的为true则不执行后面的，如果前面的为false，则会执行后面的
//上面定义的BOARD_NAME变量为空，所以BOARD_NAME变量就等于$1
[ $# -lt 4 ] && exit 1
[ $# -gt 6 ] && exit 1
echo "Configuring for ${BOARD_NAME} board..." //这句就是我们执行make x210_sd_config之后看到的那句话
#
# Create link to architecture specific headers
#
if [ "$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 //创建asm链接文件 asm -> asm-arm
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
# create link for s5pc11x SoC
if [ "$3" = "s5pc11x" ] ; 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 //一个>是创建文件并写入
echo "CPU = $3" >> config.mk //两个>>是向其后的文件中追加内容
echo "BOARD = $4" >> config.mk
[ "$5" ] && [ "$5" != "NULL" ] && echo "VENDOR = $5" >> config.mk
[ "$6" ] && [ "$6" != "NULL" ] && echo "SOC = $6" >> config.mk
上面这五行就是创建include目录下的那个config.mk文件的，就是在主Makefile的133行包含的那个文件include $(obj)include/config.mk
并将这五个变量导出为环境变量export ARCH CPU BOARD VENDOR SOC
#
# Create board specific header file
#
if [ "$APPEND" = "yes" ] # Append to existing config file
then
echo >> config.h
else //最上面的APPEND变量等于no,故走else分支
> config.h # Create new config file //在include目录下新建一个config.h
fi
echo "/* Automatically generated - do not edit */" >>config.h //因为该文件是自动生成的,所以不要在里面编辑
echo "#include <configs/$1.h>" >>config.h //并将这两句话输入到include/config.h文件中
exit 0