Is RISC-V Finally Taking Off?

Alasdair Allan
3 min readFeb 19, 2018

Created by researchers at Berkeley, the RISC-V architecture has been around since 2010, but had remained mostly theoretically until very recently. So the arrival of the first commercially-available open source system-on-chip (SoC) based on the architecture—the 32-bit Freedom Everywhere 310—along with the first Arduino-compatible development board called the HiFive1, from the Bay Area startup SiFive, was seen as a real milestone for the open hardware community.

However just over a year since the first commercial silicon arrived, the new SiFive 64-bit Linux-capable SoC platform—called the HiFive Unleashed—may well turn out to be a lot more important in the long run.

The HiFive Unleashed. (📷: SiFive)

Announced at FOSDEM 2018 at the beginning of the month—in the wake of the completion of the RISC-V ports of binutils, GCC, Linux, and glibc—the new HiFive Unleashed board is the world’s first RISC-V-based, Linux-capable development board.

Based around SiFive’s Freedom U500 platform, the 64-bit quad-core Freedom U540 chip at the heart of the board runs at 1.5GHz. The board, measuring 120 mm x 90 mm in size, has a Gigabit Ethernet port, 8GB of DDR4 memory, and 32 MB quad SPI flash, along with a micro-SD card slot for removable storage, and an FMC connector for future expansion.

In the lead up to the release of the new board there is a beta programme going on where early-access developers can get their hands on an FPGA-based version of the board which will be replaced by a real board after they ship. Aimed at kernel developers, distribution maintainers, bootloader and firmware hackers, the beta programme is to try and get the community ready for the new board release and if you’re interested in getting involved you need to email SiFive.

Yet even with that run up, it’s likely the main use cases for the new HiFive Unleashed board will be to add features to the RISC-V Linux port, and begin porting packages to the new architecture. More mainstream adoption will likely have to wait until the Linux distributions running on the are more mature.

While it’s unclear at the moment how well received the new board will be, we can take a look at the reception of SiFive’s previous 32-bit offering to gauge the community’s response, and there signs are promising.

A year or so from its initial release, the Freedom E310 silicon is starting to show up in third-party boards. So if you want a board built around a RISC-V SoC, the boards from SiFive are now not your only option. Along with that ports of languages like MicroPython are starting to appear.

The community support we’re seeing for the current generation of 32-bit RISC-V is a hopeful sign that the new 64-bit processor might also see good support.

If you’re interested in getting your hands on the new HiFive Unleased the board is expected to ship early adopters at the end of next month, and in volume towards the middle of year. Early access boards will cost $1,250, while production boards will cost $999. The high cost presumably down to the fact that these are the very first processors off the fab, and the very first boards off the line, so hopefully the cost of Freedom U500 boards will drop over time.