pi4 alpine-linux headless installation¶

准备¶

uart adapter
ethernet connection
sd card
- mmcblk0p1 fat32 256M
- mmcblk0p2 ext4/f2fs 200M+

下载解压到mmcblk0p1

https://dl-cdn.alpinelinux.org/alpine/v3.14/releases/aarch64/alpine-rpi-3.14.1-aarch64.tar.gz

修改cmdline.txt

modules=loop,squashfs,sd-mod,usb-storage earlycon=uart8250,mmio32,0xfe215040 loglevel=7 console=ttyS0,115200

创建usercfg.txt
```
enable_uart=1
gpu_mem=32
```

安装¶

联网
```
setup-interfaces
setup-ntp
```

挂载mmcblk0p2
```
mount /dev/mmcblk0p2 /mnt
```

安装基础包到mmcblk0p2

apk -X https://mirrors.bfsu.edu.cn/alpine/latest-stable/main/ -p /mnt/ --initdb -U --allow-untrusted \
add alpine-base linux-rpi4 e2fsprogs f2fs-tools util-linux dosfstools rng-tools

重新挂载mmcblk0p1
```
mount -o remount,rw /media/mmcblk0p1
```

复制基础包中的kernel和initramfs到mmcblk0p1
```
cp /mnt/boot/*-rpi4 /media/mmcblk0p1/
```

修改cmdline.txt

earlycon=uart8250,mmio32,0xfe215040 loglevel=7 console=ttyS0,115200 root=/dev/mmcblk0p2 rootwait fsck.repair=yes

修改usercfg.txt

enable_uart=1
gpu_mem=32
[pi4]
enable_gic=1
kernel=vmlinuz-rpi4
initramfs initramfs-rpi4

chroot
```
chroot /mnt /bin/sh
```

基础服务

for s in devfs procfs sysfs dmesg mdev hwdrivers; do rc-update add $s sysinit;done

for s in swclock hostname modules sysctl bootmisc syslog rfkill rngd networking;do rc-update add $s boot;done

for s in savecache killprocs mount-ro;do rc-update add $s shutdown;done

修改密码
```
passwd
```

启用ttyS0

#/etc/inittab
ttyS0::respawn:/sbin/getty -L ttyS0 115200 vt100

OR

#https://github.com/OpenRC/openrc/blob/master/agetty-guide.md
cd /etc/init.d && ln -s agetty agetty.ttyS0
rc-update add agetty.ttyS0 boot

退出chroot并重启
```
exit
reboot
```

post-install¶

/boot

# 清空mmcblk0p1只保留txt文件
# 移动/boot内文件到mmcblk0p1
# 之后将mmcblk0p1挂载为/boot
mkdir -p /media/mmcblk0p1
mount /dev/mmcblk0p1 /media/mmcblk0p1
cp /media/mmcblk0p1/*.txt /boot/
rm -rf /media/mmcblk0p1/*
rm /boot/boot
mv /boot/* /media/mmcblk0p1/
echo -e '/dev/mmcblk0p1 /boot vfat defaults 0 0\n' >/etc/fstab
reboot

开局

setup-interfaces
setup-ntp
setup-apkrepos
setup-timezone

疑似headless用不上的模块

blacklist videodev
blacklist videobuf2_common
blacklist videobuf2_v4l2
blacklist v4l2_mem2mem
blacklist bcm2835_v4l2
blacklist bcm2835_isp
blacklist bcm2835_codec
blacklist videobuf2_vmalloc
blacklist videobuf2_dma_contig
blacklist videobuf2_memops
blacklist rpivid_mem
blacklist bcm2835_mmal_vchiq
blacklist mc
blacklist vc_sm_cma

backup/restore rootfs¶

sudo tar --acls --xattrs --xattrs-include='*' -cpf root.tar -C /mntpoint . #<--there's a dot
sudo tar --acls --xattrs --xattrs-include='*' -xpf root.tar -C /mntpoint/