U-BOOT分析与移植之mkconfig分析篇

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#命令行参数 make smdk2410_config 就是执行./mkconfig smdk2410 arm arm920t smdk2410 NULL s3c24x0

原因就是makefile中的

smdk2410_config : unconfig

@$(MKCONFIG) $(@:_config=) arm arm920t smdk2410 NULL s3c24x0

#mkconfig的作用：

1 BOARD_NAME=smdk2410

2建立链接

asm-arm<--asm

arch-s3c24x0<--asm-arm/arch

proc-armv<--asm-smdk2410/proc

3 创建include/config.mk

ARCH＝arm

CPU=arm920t

BOARD=smdk2410

SOC=s3c24x0

4 创建include/config.h

/* Automatically generated - do not edit */

#include <configs/$1.h>

#确定开发板的名称BOARD_NAME

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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" #在BOARD_NAME不空的情况下，BOARD_NAME即为第一个参数 smdk2410

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#生成链接指向特定架构头文件

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if [ "$SRCTREE" != "$OBJTREE" ] ; then ＃判断源代码目录和目标目录是否一样

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 #使得asm链接到asm-arm

fi

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#

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if [ -z "$6" -o "$6" = "NULL" ] ; then #如果位置参数$6字符串长度为0或者为空NULL的话

ln -s ${LNPREFIX}arch-$3 asm-$2/arch #若LNPREFIX为空，等价于ln -s arch-$3 asm-$2/arch

else

ln -s ${LNPREFIX}arch-$6 asm-$2/arch #建立软链接：ln -s arch-s3c24x0 asm-arm/arch

fi

if [ "$2" = "arm" ] ; then

rm -f asm-$2/proc

ln -s ${LNPREFIX}proc-armv asm-$2/proc

fi

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#为MAKE生成include文件，include/config.mk

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echo "ARCH = $2" > config.mk #将 “ARCH＝arm“重定向到config.mk文件

echo "CPU = $3" >> config.mk #将"CPU=arm920t"追加到config.mk文件的尾部

echo "BOARD = $4" >> config.mk

[ "$5" ] && [ "$5" != "NULL" ] && echo "VENDOR = $5" >> config.mk

[ "$6" ] && [ "$6" != "NULL" ] && echo "SOC = $6" >> config.mk

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#创建开发板相关头文件 include/config.h

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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.h