Geological evolution times: Ubuntu for next RISC-V board

Computers and single-board computers with RISC-V-based system-on-a-chip (SoCs) are not only coveted by hobbyists. With the Milk-V Mars SBC, Ubuntu officially supports another RISC-V system.

The Milk-V Mars now appears on the Ubuntu download page for RISC-V machines. Two versions are available: Ubuntu Server 24.04 as a "preinstalled image" and an "Ubuntu Server live installer". Anyone expecting at least a rudimentary desktop system will be disappointed: the high performance promised by Ubuntu in a related blog post is not delivered, and Ubuntu Server for RISC-V is apparently currently intended for terminal operation (headless, i.e. without mouse and monitor).

Ubuntu: Support for new board with old processor

In fact, the now universally praised user experience is likely to be rather poor. The JH7110 processor is also used on the Starfive Visionfive-2 and has been supported by Ubuntu for almost exactly one year. Better speed is therefore not to be expected. The only significant difference is the form factor. The Visionfive-2 roughly fits the PicoITX format (10 cm × 7.2 cm) and is therefore 60 percent larger than the Raspberry Pi format followed by the Milk-V Mars (8.5 cm × 5.6 cm), which leads the manufacturer to say it is a "credit card-sized single-board computer".

The installation instructions clearly show that Ubuntu on the Milk-V Mars, like on the Visionfive-2, is aimed more at hard-boiled users. The U-Boot bootloader is not compatible ex works and cannot start Ubuntu without changes. For the SD card image, it is therefore necessary to at least change the boot switches. But according to the description, some other rework is also necessary to get the Ubuntu server up and running.

In addition, there are already known limitations: The GPU of the JH7110 is not supported, PCIe support is limited to NVMe drives and cannot address WLAN cards or external GPUs. The three USB3 ports work, but the Linux kernel 6.8 used in Ubuntu cannot address the USB 2.0 port. Some of this fiddling has been known for a year from Ubuntu on the Visionfive-2.

Development at a snail's pace

RISC-V systems with at least sufficient computing power and memory expansion for everyday desktop tasks have now been available for over a year in affordable and therefore interesting machines for end users. In contrast to the Raspberry Pi, for example, the development of usable Linux distributions seems to have come to a standstill. Support from the distributions themselves is still limited to headless systems and is considered experimental. Even the Linux distribution DietPi, which specializes in SBCs, no longer delivers. Only Debian, for example, which has been massively adapted to Visionfive-2 by Starfive, can offer a graphical desktop, but does not meet current security standards due to standard log-ins.

The processors are also rather slow by today's standards. New developments such as the SpacemiT Keystone K1 are intended to provide more speed. The Keystone K1 comes with additional peripherals, such as an AI accelerator or a 256-bit vector unit. An adapted version of Ubuntu is to be used as the operating system - although there is no information about this on the Ubuntu website - or the company's own operating system "Bianbu OS".

(dmk)