Alpine Linux Milk-V Duo Test Report

Test Environment

Operating System Information

• System Version: 3.21.3
• Download Link:
  • Alpine minirootfs: https://alpinelinux.org/downloads/
  • Official Buildroot image: https://github.com/milkv-duo/duo-buildroot-sdk/releases
• Reference Installation Document:
  • Alpine Wiki (Installation)
  • Alpine Wiki (How to make a cross architecture chroot)
  • Milk-V forum thread

Hardware Information

• Milk-V Duo
• A USB-A to C or USB-C to C cable
• A microSD card
• A microSD card reader
• A USB to UART debugger (e.g., CH340, CH341, FT2232, etc.)
• Optional: Milk-V Duo IOB (Baseboard)

Installation Steps

Download Alpine minirootfs and Buildroot image

wget https://dl-cdn.alpinelinux.org/alpine/v3.21/releases/riscv64/alpine-minirootfs-3.21.3-riscv64.tar.gz
tar -xvf alpine-minirootfs-3.21.3-riscv64.tar.gz --one-top-level
wget https://github.com/milkv-duo/duo-buildroot-sdk/releases/download/v1.1.4/milkv-duo-sd-v1.1.4.img.zip
unzip milkv-duo-sd-v1.1.4.img.zip

Prepare rootfs

Note that the obtained Alpine system is only a “minirootfs” without system packages such as OpenRC. We need to install Alpine’s base packages using apk inside the rootfs in order to make it bootable.

Install Alpine’s package manager apk

Skip this step if using Alpine-based distributions on host.

wget https://gitlab.alpinelinux.org/api/v4/projects/5/packages/generic/v2.14.10/x86_64/apk.static
chmod +x apk.static
mv apk.static /usr/bin/apk

Install Alpine’s base package alpine-base inside minirootfs

(chroot is NOT required)

cd alpine-minirootfs-3.20.3-riscv64
sudo apk add -p . --initdb -U --arch riscv64 --allow-untrusted alpine-base

Extra setups

1. Edit ./etc/inittab and add the following line (or uncomment) to enable serial access on /dev/ttyS0:

   ttyS0::respawn:/sbin/getty -L 115200 ttyS0 vt100

   And comment out the six lines starting with tty1 - tty6.

2. Edit ./etc/passwd:

   Remove the x in root:x:0:0:root:/root:/bin/sh.

   (Alternatively, edit /etc/shadow and remove the * in root:*::0:::::).

3. Enable the OpenRC hostname service (for setting up the hostname correctly)：

   ln -s ./etc/init.d/hostname ./etc/runlevels/boot

   You may enable other OpenRC system services of interest likewise.

Flash Buildroot image

cd ..
sudo dd if=milkv-duo-sd-v1.1.3-2024-0930.img of=/dev/your/device bs=4M status=progress

Your device should now be able to detect the rootfs and boot partitions on the SD card. Mount only the rootfs partition.

Replace root on SD card with Alpine rootfs

rm -rf /path/to/your/mnt/root/*
cp -r /path/to/your/alpine-minirootfs-3.20.3-riscv64/* /path/to/your/mnt/root/

Booting and Logging into the System

Insert SD card onto the board and boot. Login into the system via serial port at /dev/ttyUSB0, baudrate 115200.

Default username: root Default password: none

Optional post-installation setups

Setup the password and hostname with passwd and hostname after login.

Setup the system time with date -s, then install cronyd:

apk add cronyd
rc-update add chronyd default

It is recommended to enable the following system OpenRC services (though test results show that the system will still be able to boot nevertheless):

rc-update add bootmisc boot
rc-update add networking boot # make sure /etc/network/interfaces is present
rc-update add devfs sysinit
rc-update add mdev sysinit
rc-update add acpid default
rc-update add killprocs shutdown
rc-update add mount-ro shutdown
rc-update add savecache shutdown

Expected Results

The system should boot normally and allow login through the onboard serial port.

Actual Results

The system booted successfully, and login through the onboard serial port was also successful.

Boot Log

   OpenRC 0.55.1 is starting up Linux 5.10.4-tag- (riscv64)

 * Mounting /proc ... [ ok ]
 * Mounting /run ... [ ok ]
 * /run/openrc: creating directory
 * /run/lock: creating directory
 * /run/lock: correcting owner
 * Caching service dependencies ... [ ok ]
 * Clock skew detected with `/etc/init.d'
 * Adjusting mtime of `/run/openrc/deptree' to Wed Apr 30 19:42:03 2025

 * WARNING: clock skew detected!
 * WARNING: clock skew detected!
 * WARNING: clock skew detected!

Welcome to Alpine Linux 3.21
Kernel 5.10.4-tag- on an riscv64 (/dev/ttyS0)

(none) login: root
Welcome to Alpine!

The Alpine Wiki contains a large amount of how-to guides and general
information about administrating Alpine systems.
See <https://wiki.alpinelinux.org/>.

You can setup the system with the command: setup-alpine

You may change this message by editing /etc/motd.

login[206]: root login on 'ttyS0'
(none):~# uname -a
Linux (none) 5.10.4-tag- #1 PREEMPT Fri Nov 22 11:31:04 CST 2024 riscv64 Linux
(none):~# cat /etc/os-release 
NAME="Alpine Linux"
ID=alpine
VERSION_ID=3.21.3
PRETTY_NAME="Alpine Linux v3.21"
HOME_URL="https://alpinelinux.org/"
BUG_REPORT_URL="https://gitlab.alpinelinux.org/alpine/aports/-/issues"
(none):~# 

Test Criteria

Successful: The actual result matches the expected result.

Failed: The actual result does not match the expected result.

Test Conclusion

Test successful.