buildroot 编译

无USB支持的

$ git clone http://github.com/buildroot/buildroot
$ cd buildroot
$ make BR2_EXTERNAL=../linux-on-litex-vexriscv/buildroot/ litex_vexriscv_defconfig
$ make

有USB host支持的

$ git clone http://github.com/buildroot/buildroot
$ cd buildroot
$ make BR2_EXTERNAL=../linux-on-litex-vexriscv/buildroot/ litex_vexriscv_usbhost_defconfig
$ make

单独配置内核

make linux-menuconfig