给树莓派增加一个Linux系统调用
Lab 4: Add a system call to raspberry Pi1.下载编译工具、Kernel源文件、固件 Firmware$ mkdir rpi$ cd rpi$ git clone git://github.com/raspberrypi/firmware.git PRiFirmware$ git clone git://github.com/raspberrypi/linux.git RpiLinux$ git clone git:/...