手把手搭建ARM交叉编译环境

http://blog.csdn.net/goodwillyang/article/details/39779183

这篇文章主要讲搭建基于ARM(BBB)的交叉编译环境，开发环境 BBB+ubuntu14 照惯例，先贴上参考链接

1. 创建工作目录

sudo mkdir -p /usr/local/arm >/dev/null 
sudo chmod 777 /usr/local/arm
cd /usr/local/arm

*mkdir -p 创建多层目录

2.下载toolchain

法一. 对于UbuntuTrusty Tahr (14.04LTS)

Linaro maintains cross compilers that run on Ubuntu.With current releases, the method for adding a foreign architecture isslightly more complicated than for Debian. Please note — thisworks on Ubuntu 14 and later.

sudo apt-get install python-software-properties
sudo add-apt-repository universe
sudo apt-get update
sudo apt-get install gcc-arm-linux-gnueabi
sudo apt-get install qemu-system-arm qemu-system-x86

法二. 从 linaro官网下载bin文件 点击打开链接

cd /usr/local/arm
wget -c https://releases.linaro.org/14.09/components/toolchain/binaries/gcc-linaro-arm-linux-gnueabihf-4.9-2014.09_linux.tar.xz
tar -xvJf gcc-linaro-arm-linux-gnueabihf-4.9-2014.09_linux.tar.xz
ln -s gcc-linaro-arm-linux-gnueabihf-4.9-2014.09_linux  /usr/local/arm/toolchain

*ln -s src dest, 删除软连接, rm -rf symbolic_name(目标文件) 注意不是rm -rf symbolic_name/ see ln

3. 安装c-compile cache ccache

cd /usr/local/arm/toolchain
mkdir bin-ccache
cd bin-ccache
sudo apt-get install ccache
ln -s $(which ccache) arm-linux-gnueabihf-gcc
ln -s $(which ccache) arm-linux-gnueabihf-g++
ln -s $(which ccache) arm-linux-gnueabihf-cpp
ln -s $(which ccache) arm-linux-gnueabihf-c++

* ccache -s 显示状态  ccache -c means clean up ccache -C means clear all

4.设置环境变量

export PATH=/usr/local/arm/toolchain/bin-ccache:/usr/local/arm/toolchain/bin:$PATH
export CROSS_COMPILE=arm-linux-gnueabihf-
export ARCH=arm

编译uboot时出现的问题

lib/asm-offsets.c:1: error: bad value (armv5) for -march= switch

原因是没有指定交叉编译工具链。设置环境变量，或者make时带上CROSS_COMPILE参数。如make CROSS_COMPILE=arm-none-linux-gnueabi-,注意compile不是compiler

修改环境变量，把交叉编译器的路径加入到PATH。
方法一：修改/etc/bash.bashrc文件（此文件只对当前用户适用）
在最后加上export PATH＝

$sudo gedit /etc/bash.bashrc
export PATH=/usr/local/arm/toolchain/bin-ccache:/usr/local/arm/toolchain/bin:$PATH

方法二：修改/etc/profile文件（此文件属于系统级别的环境变量，设置在里面的东西对所有用户适用

$sudo gedit /etc/profile
export PATH=/usr/local/arm/toolchain/bin-ccache:/usr/local/arm/toolchain/bin:$PATH

方法三：修改/etc/environment文件

$sudo gedit /etc/environment
export PATH=...............

http://blog.csdn.net/goodwillyang/article/details/39779183