U-BOOT分析與移植之mkconfig分析篇

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#命令列參數  make smdk2410_config 就是執行./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建立連結

asm-arm<--asm
arch-s3c24x0<--asm-arm/arch
proc-armv<--asm-smdk2410/proc
3 建立include/config.mk
ARCH＝arm
CPU=arm920t
BOARD=smdk2410
SOC=s3c24x0
4 建立include/config.h
/* Automatically generated - do not edit */
#include <configs/$1.h>

#確定開發板的名稱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="$1"  #在BOARD_NAME不空的情況下，BOARD_NAME即為第一個參數 smdk2410
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#產生連結指向特定架構標頭檔
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if [ "$SRCTREE" != "$OBJTREE" ] ; then    ＃判斷原始碼目錄和目標目錄是否一樣
    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連結到asm-arm
fi
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#
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if [ -z "$6" -o "$6" = "NULL" ] ; then           #如果位置參數$6字串長度為0或者為空白NULL的話
    ln -s ${LNPREFIX}arch-$3 asm-$2/arch  #若LNPREFIX為空白，等價於ln -s arch-$3 asm-$2/arch
else
    ln -s ${LNPREFIX}arch-$6 asm-$2/arch  #建立軟連結：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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#為MAKE產生include檔案，include/config.mk
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echo "ARCH   = $2" >  config.mk   #將 “ARCH＝arm“重新導向到config.mk檔案
echo "CPU    = $3" >> config.mk   #將"CPU=arm920t"追加到config.mk檔案的尾部
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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#建立開發板相關標頭檔 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