Install Ubuntu on the Milk-V Mars CM and CM Lite

The Milk-V Mars CM is a RISC-V based SBC.

Using the pre-installed server image

  1. Download one of the supported images:

  2. Flash the pre-installed server image to a USB drive.

  3. Attach the USB drive.

  4. Connect a USB UART adapter to the UART on the GPIO header (see UART console and Connect to a UART console)

  5. Power on the board

  6. When “Hit any key to stop autoboot” is displayed, press Enter

  7. Reset the U-Boot environment with the following command:

    env erase

  8. Power cycle the board

  9. Wait for an output line confirming that cloud-init has finished running; this service is responsible for generating SSH keys, and creating the default user:

    [   35.682018] cloud-init[909]: Cloud-init v. 24.1.3-0ubuntu3 finished at Tue, 23 Apr 2024 07:44:59 +0000. Datasource DataSourceNoCloud [seed=/var/lib/cloud/seed/nocloud-net][dsmode=net].  Up 35.65 seconds

  10. Login with the user ubuntu and the default password ubuntu; you will be asked to choose a new password

Using the live server image

The live installer image is used to install Ubuntu to an eMMC, USB, or NVMe drive. To boot the live image, U-Boot must be installed on the SPI flash.

Warning

The vendor U-Boot is not compatible with EBBR and cannot boot Ubuntu without manual changes.

Install U-Boot to the SPI flash

  1. Download package package u-boot-starfive from https://launchpad.net/ubuntu/+source/u-boot/

  2. Unpack the debian package with

    dpkg -x u-boot-starfive*.deb u-boot-starfive

  3. Copy the following files from package u-boot-starfive to a USB drive:

    • u-boot-starfive/usr/lib/u-boot/starfive_visionfive2/u-boot.bin

    • u-boot-starfive/usr/lib/u-boot/starfive_visionfive2/u-boot-spl.bin.normal.out

  4. Connect a USB UART adapter to the UART on the GPIO header (see UART console and Connect to a UART console)

  5. Power on the board

  6. When “Hit any key to stop autoboot” is displayed, press Enter

  7. Enter the following commands to flash U-Boot to SPI:

    sf probe
load usb 0:1 $kernel_addr_r u-boot-spl.bin.normal.out
sf update $kernel_addr_r 0 $filesize
load usb 0:1 $kernel_addr_r u-boot.itb
sf update $kernel_addr_r 0x100000 $filesize

  8. Switch the board off

  9. Power on the board

  10. When “Hit any key to stop autoboot” is displayed, press Enter

  11. Enter the following commands to reset the U-Boot environment:

    env default -f -a
env save

  12. Switch the board off

Boot the live server image

  1. Download one of the supported images.

  2. Flash the live server image to a USB drive.

  3. Attach the USB drive.

  4. Connect a USB UART adapter to the UART on the GPIO header (see UART console and Connect to a UART console)

  5. Power on the board

  6. If no prior operating system installation exists, U-Boot will start up GRUB on the USB drive. In this case you can skip the next step.

  7. If a prior operating system exists, press Enter when “Hit any key to stop autoboot” is displayed, and enter:

    load mmc 1:1 $fdt_addr_r dtb/starfive/jh7110-starfive-visionfive-2-v1.3b.dtb
# for the 1.2a version of the board:
# load mmc 1:1 $fdt_addr_r dtb/starfive/jh7110-starfive-visionfive-2-v1.2a.dtb
load mmc 1:1 $kernel_addr_r EFI/boot/bootriscv64.efi
bootefi $kernel_addr_r $fdt_addr_r

  8. From the GRUB menu, select “Try or Install Ubuntu Server”

  9. Loading the installer takes some time. Once it is loaded, follow the Ubuntu Server installation tutorial

Note

U-Boot does not allow the operating system to write UEFI variables. You can do this manually using U-Boot’s eficonfig command.

NVMe support

For attaching an NVMe drive the Waveshare CM4-IO-BASE-A board can be used.

Warning

On the Raspberry Pi Compute Module 5 IO Board NVMe drives do not work.

The Milk-V Mars CM does not drive the line PCIE_PWR_EN to enable power to the m.2 connector.

Boot source selection

The Milk-V Mars CM board can boot firmware from SPI flash or UART. The boot source is selected via the nRPIBOOT line. When connected to ground, booting from UART is selected.

On the Waveshare CM4-IO-BASE-A board a switch labeled “BOOT” is connected to the nRPIBOOT line. Switch it to to “OFF” to boot from SPI flash and to “ON” to boot from UART.

Boot select

UART console

The UART is available on the Waveshare CM4-IO-BASE-A board via the GPIO connector. Assuming the typical coloring of USB to TTL serial adapters the following connections have to be made:

Board

Adapter

GND, pin 6

GND, black

TX, pin 8

RX, white

RX, pin 10

TX, green

Do not connect the red 3.3 V wire.

UART

Connect with the following settings (see Connect to a UART console):

  • 115200 baud

  • 8 data bits

  • no parity

  • 1 stop bit

  • no flow control

Limitations

  • The on-board GPU is not supported

  • PCIe support is incomplete: an NVMe drive can be used, but Wi-Fi cards and external GPUs don’t work

  • While the 3 USB 3.0 ports are working, the USB 2.0 port is not supported by the 6.8 kernel