一.下载ubuntu-base
https://cdimage.ubuntu.com/ubuntu-base/releases/20.04.5/release/
下载固件：buntu-base-20.04.5-base-arm64.tar.gz
根文件系统创建目录ubuntu_rootfs，并解压到该目录：
mkdir ubuntu_rootfs tar -zxvf ubuntu-base-20.04.5-base-arm64.tar.gz -C ubuntu_rootfs
二.构建根文件系统
2.1、配置网络配置
cp /etc/resolv.conf ubuntu_rootfs/etc/
2.2、配置仿真开发环境
sudo apt install qemu-user-static sudo cp /usr/bin/qemu-aarch64-static ubuntu_rootfs/usr/bin/
2.3、更换软件源
1 sudo vim ubuntu_rootfs/etc/apt/sources.list
deb http://mirrors.aliyun.com/ubuntu-ports/ focal main restricted deb http://mirrors.aliyun.com/ubuntu-ports/ focal-updates main restricted deb http://mirrors.aliyun.com/ubuntu-ports/ focal universe deb http://mirrors.aliyun.com/ubuntu-ports/ focal-updates universe deb http://mirrors.aliyun.com/ubuntu-ports/ focal multiverse deb http://mirrors.aliyun.com/ubuntu-ports/ focal-updates multiverse deb http://mirrors.aliyun.com/ubuntu-ports/ focal-backports main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu-ports/ focal-security main restricted deb http://mirrors.aliyun.com/ubuntu-ports/ focal-security universe deb http://mirrors.aliyun.com/ubuntu-ports/ focal-security multiverse
2.4、挂载根文件系统
2.4.1、编写mount.sh脚本
vim mount.h
#!/bin/bash function mnt() { echo "MOUNTING" sudo mount -t proc /proc ${2}proc sudo mount -t sysfs /sys ${2}sys sudo mount -o bind /dev ${2}dev #sudo mount -t devpts -o gid=5,mode=620 devpts ${2}dev/pts sudo mount -o bind /dev/pts ${2}dev/pts sudo chroot ${2} } function umnt() { echo "UNMOUNTING" sudo umount ${2}proc sudo umount ${2}sys sudo umount ${2}dev/pts sudo umount ${2}dev } if [ "$1" == "-m" ] && [ -n "$2" ]; then mnt $1 $2 elif [ "$1" == "-u" ] && [ -n "$2" ]; then umnt $1 $2 else echo "" echo "Either 1'st, 2'nd or both parameters were missing" echo "" echo "1'st parameter can be one of these: -m(mount) OR -u(umount)" echo "2'nd parameter is the full path of rootfs directory(with tralling '/')" echo "" echo "For example: ch-mount -m /media/sdcard" echo "" echo 1st parameter : ${1} echo 2nd parameter : $[2] fi
2.4.2、增加权限、挂载、卸载
#增加脚本执行权限 sudo chmod +x mount.sh #挂载根文件系统 ./mount.sh -m ubuntu_rootfs/ #退出根文件系统 exit #卸载根文件系统 ./mount.sh -u ubuntu_rootfs/
2.5、安装一些必要软件
先apt-get update，发现有以下报错：
root@m5280:/# apt-get update Get:1 http://mirrors.aliyun.com/ubuntu-ports focal InRelease [265 kB] Get:2 http://mirrors.aliyun.com/ubuntu-ports focal-updates InRelease [114 kB] Err:1 http://mirrors.aliyun.com/ubuntu-ports focal InRelease Couldn't create temporary file /tmp/apt.conf.wxDXeG for passing config to apt-key Err:2 http://mirrors.aliyun.com/ubuntu-ports focal-updates InRelease Couldn't create temporary file /tmp/apt.conf.IPDhqR for passing config to apt-key Get:3 http://mirrors.aliyun.com/ubuntu-ports focal-backports InRelease [108 kB] Err:3 http://mirrors.aliyun.com/ubuntu-ports focal-backports InRelease Couldn't create temporary file /tmp/apt.conf.6tYJ0X for passing config to apt-key Get:4 http://mirrors.aliyun.com/ubuntu-ports focal-security InRelease [114 kB] Err:4 http://mirrors.aliyun.com/ubuntu-ports focal-security InRelease Couldn't create temporary file /tmp/apt.conf.TLSc47 for passing config to apt-key Reading package lists... Done W: GPG error: http://mirrors.aliyun.com/ubuntu-ports focal InRelease: Couldn't create temporary file /tmp/apt.conf.wxDXeG for passing config to apt-key E: The repository 'http://mirrors.aliyun.com/ubuntu-ports focal InRelease' is not signed. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. W: GPG error: http://mirrors.aliyun.com/ubuntu-ports focal-updates InRelease: Couldn't create temporary file /tmp/apt.conf.IPDhqR for passing config to apt-key E: The repository 'http://mirrors.aliyun.com/ubuntu-ports focal-updates InRelease' is not signed. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. W: GPG error: http://mirrors.aliyun.com/ubuntu-ports focal-backports InRelease: Couldn't create temporary file /tmp/apt.conf.6tYJ0X for passing config to apt-key E: The repository 'http://mirrors.aliyun.com/ubuntu-ports focal-backports InRelease' is not signed. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. W: GPG error: http://mirrors.aliyun.com/ubuntu-ports focal-security InRelease: Couldn't create temporary file /tmp/apt.conf.TLSc47 for passing config to apt-key E: The repository 'http://mirrors.aliyun.com/ubuntu-ports focal-security InRelease' is not signed. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.
借鉴网友的经验：https://blog.csdn.net/yinfang1252/article/details/105342449，需要改下tmp的权限：
chmod 777 /tmp
工具安装：
apt update
apt upgrade
apt install sudo vim udev net-tools ethtool udhcpc netplan.io language-pack-en-base language-pack-zh-han* iputils-ping openssh-sftp-server ntp usbutils alsa-utils libmtp9
2.6、卸载一些不必要的软件
apt-get remove --purge lubuntu-update-notifier
apt-get remove --purge libreoffice*
2.7、安装轻量级的桌面lubuntu-desktop
apt-get install ubuntu-desktop
2.8、添加用户：
adduser ubuntu
密码：123456
2.9、sudo权限：
chmod u+w /etc/sudoers
vim /etc/sudoers
然后在root的下一行添加新的用户【developer】，注意中间的间隔是一个TAB键：
# User privilege specification root ALL=(ALL:ALL) ALL ubuntu ALL=(ALL:ALL) ALL
2.10、启用ssh的root帐号登录
vi /etc/ssh/sshd_config
# 将下面这项设置成yes
PermitRootLogin yes
2.11、设置主机名称和IP
echo "rk3568" > /etc/hostname echo "127.0.0.1 localhost" >> /etc/hosts echo "127.0.0.1 rk3568" >> /etc/hosts
2.12、配置DHCP和网卡白名单
RK3568有两个网络端口，相应的在配置的时候我们要将两个网口都配置上
#修改网络配置文件
vim /etc/network/interfaces
以下是该文件具体内容
# interfaces(5) file used by ifup(8) and ifdown(8) # Include files from /etc/network/interfaces.d: auto eth0 iface eth0 inet dhcp auto eth1 iface eth1 inet dhcp source-directory /etc/network/interfaces.d
配置网卡：Network-Manager服务会自动配置网卡，但是其默认配置文件将Ethernet加入了黑名单，以至于以太网不能用，找不到网卡
vi /usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf
# 文件内容改为如下内容
[keyfile]
unmanaged-devices=*,except:type:ethernet,except:type:wifi,except:type:gsm,except:type:cdma
在实际测试中网口必须接入网线系统才能正常启动，就是在不联网的情况下，每次开机都要等待很久，
卡在网络连接上5分钟，这里我们可以修改下面这个文件：
vim /lib/systemd/system/networking.service //将里面的TimeoutStartSec=5min修改为 TimeoutStartSec=5sec
2.13、修改系统重启默认等待时间
vim /etc/systemd/system.conf 解除注释并将 DefaultTimeoutStopSec=90s 改为： DefaultTimeoutStopSec=3s
2.14、禁用系统休眠：
sudo systemctl mask sleep.target suspend.target hibernate.target hybrid-sleep.target
实测加了这条指令，系统也会进入休眠。why？
2.15、设置开机串口免密登录到图形界面
2.15.1
vim /etc/gdm3/custom.conf 添加 [daemon] AutomaticLoginEnable=true AutomaticLogin=ubuntu TimedLoginEnable=true TimedLogin=root TimedLoginDelay=10
2.15.2
vim /etc/pam.d/gdm-password
注释：#auth required pam_succeed_if.so user != root quiet_success
2.15.3
vim /usr/share/lightdm/lightdm.conf.d/50-ubuntu.conf
末行添加： greeter-show-manual-login=true all-guest=false
2.15.4
vim /etc/pam.d/gdm-autologin
注释：#auth required pam_succeed_if.so user != root quiet_success
2.15.5、
vi /root/.profile 将文件最后一行mesg n 2> /dev/null || true改为以下内容： tty -s && mesg n || true
2.15.6、串口自动登录
vim /lib/systemd/system/serial-getty\@.service 注释：ExecStart=-/sbin/agetty -o ‘-p – \u’ --keep-baud 115200,38400,9600 %I $TERM 修改：ExecStart=-/sbin/agetty --autologin root --noclear %I $TERM
2.16、添加分区释放的系统服务（非常重要）
2.16.1、默认是对/dev/mmcblk0p6分区进行扩充，创建一个脚本firstboot.sh和服务来扩充分区：
vim etc/init.d/firstboot.sh #!/bin/bash -e # first boot configure # resize filesystem mmcblk0p6 if [ ! -e "/usr/local/first_boot_flag" ] ; then echo "Resizing /dev/mmcblk0p6..." resize2fs /dev/mmcblk0p6 touch /usr/local/first_boot_flag fi
添加权限：
chmod +x etc/init.d/firstboot.sh
2.16.2、创建服务firstboot.service去运行脚本
vim lib/systemd/system/firstboot.service #start [Unit] Description=Setup wmc-rockchip platform environment Before=lightdm.service After=resize-helper.service [Service] Type=simple ExecStart=/etc/init.d/firstboot.sh [Install] WantedBy=multi-user.target #end
启动服务：systemctl enable firstboot.service
查看服务状态： systemctl status firstboot
一开始，由于服务service写的有问题，导致脚本没有运行到，扩容没有成功，由于/目录没有磁盘空间了，也就进不了ubuntu桌面环境的，一直卡在开机logo画面，但通过串口实际已经进入到系统了。可以手动执行resize2fs /dev/mmcblk0p6，然后重启就正常进入到桌面了。
三.打包根文件系统镜像
3.1、创建空镜像文件，大小为6144MB
dd if=/dev/zero of=ubuntu_rootfs.img bs=1M count=6144
3.2、将该文件格式化成ext4文件系统
mkfs.ext4 ubuntu_rootfs.img
3.3、将该镜像文件挂载到一个空的文件夹ubuntu_base_rootfs上，然后将ubuntu_rootfs的文件复制到该空文件夹中
mkdir ubuntu_base_rootfs chmod 777 ubuntu_base_rootfs sudo mount ubuntu_rootfs.img ubuntu_base_rootfs sudo cp -rfp ubuntu_rootfs/* ubuntu_base_rootfs/
3.4、复制完后用e2fsck修复及检测镜像文件系统，resize2fs 减小镜像文件的大小
sudo umount ubuntu_base_rootfs/ e2fsck -p -f ubuntu_rootfs.img resize2fs -M ubuntu_rootfs.img
至此，文件系统镜像制作完成。
四、将文件系统烧录到主板
为了简便，先在主板上烧录调试好的debian系统，然后再单独烧录Ubuntu文件系统
