The lowRISC blog

An update on Ibex, our microcontroller-class CPU core

At the beginning of many chips projects, there’s a dream. Could we create a more future-proof chip by embedding an FPGA fabric into it? Could we measure glucose levels more accurately by integrating a small bio lab onto a chip? Could we more reliably recognize kittens in a set of pictures by implementing neural network inference in hardware? In implementation, this dream becomes a piece of hardware, with digital or analog logic, sensors, actuators, and much more.

Introducing Pirmin & Laura

Pirmin Vogel and Laura James both joined lowRISC on May 1st this year. A few weeks in to their new roles, they each share thoughts on what attracted them to work at lowRISC. Pirmin: “After having traveled around the world for 6 months, I finally started my new position as hardware/software engineer at lowRISC C.I.C. in Cambridge at the beginning of May. At lowRISC, we are working on open-source hardware/software ecosystems with a fully open-sourced, Linux-capable, RISC-V-based SoC being the ultimate goal.

Onwards and upwards at lowRISC

If you haven’t checked it out yet, be sure to take a look at our press release and the corresponding Google blog post. This industry support and growth of our board is a huge step forwards for lowRISC. As Royal Hansen, vice president of Security, Google, said: "Google believes that open source is good for everyone. To further our commitment, we are investing both capital and engineering resources to create a sustainable open source hardware ecosystem.

lowRISC Expands and Appoints New Members to the Board of Directors from Google and ETH Zurich

London, England - lowRISC C.I.C., the open source system on a chip (SoC) organisation, today announced that Prof. Luca Benini (ETH Zurich), Dominic Rizzo (Google) and Ron Minnich (Google) have joined its board of directors. The announcement coincides with a new phase of hiring by lowRISC with the goal of significantly increasing the size of its Cambridge-based engineering team during 2019. lowRISC is a not-for-profit, community-driven organisation working to provide a high quality, security-enabling, open SoC base for derivative designs.

lowRISC at the SiFive Symposium in Cambridge

Several lowRISC team members attended the SiFive Symposium in our home town of Cambridge on May 13th 2019, a lovely sunny day. Imagination Technologies were co-hosting with SiFive, and we heard from both companies. Krste Asanovic, chairman of the board at the RISC-V Foundation, gave a great introduction to RISC-V and progress so far. Naveed Sherwani, CEO of SiFive, talked us through their silicon design platform and future services. We also heard from SecureRF and IAR Systems.

lowRISC 0-6 milestone release

The lowRISC 0.6 milestone release is now available. This release includes an updated version of the Rocket RISC-V core, a higher core clock frequency, JTAG debugging support, Ethernet improvements, and more. See the release notes, for full details. We’ve also taken the opportunity to re-organise our documentation, adding an easy to follow quick-start guide. Our next development focus is to add support for dropping in the Ariane RISC-V design (from ETH Zurich) as an alternative to Rocket.

Barcelona RISC-V Workshop: Day Two

The eighth RISC-V workshop is continuing today in Barcleona. As usual, I’ll be keeping a semi-live blog of talks and announcements throughout the day. Look back here for the day one live blog. Note that slides from most presentations are now available at riscv.org. Fast interrupts for RISC-V: Krste Asanovic Embedded is a major use for RISC-V. There is a desire for faster interrupt handling with support for nested preempted interrupts.

Barcelona RISC-V Workshop: Day One

The eighth RISC-V workshop is going on today in Barcleona. As usual, I’ll be keeping a semi-live blog of talks and announcements throughout the day. Follow here for the day two live blog. Note that slides from most presentations are now available at riscv.org. Introduction: Rick O’Connor This workshop has 325 attendees representing 101 companies and 25 universties. Largest outside of Silicon Valley. Rick gives the usual overview of the RISC-V Foundation structure.

lowRISC 0-5 milestone release

The lowRISC 0.5 milestone release is now available. The various changes are best described in our accompanying documentation, but the main focus is the integration of open-source Ethernet IP. The tutorial demonstrates how to use Ethernet support to boot with an NFS root, as well as with a rootfs on SD card. Our main development focus currently is migrating to a newer version of the upstream Rocket chip design and reintegrating our changes on top of that, but we felt that the integration of Ethernet support merits a release before that change.

Seventh RISC-V Workshop: Day Two

The seventh RISC-V workshop is concluding today at Western Digital in Milpitas. I’ll be keeping a semi-live blog of talks and announcements throughout the day. Celerity: An Open Source 511-core RISC-V Tiered Accelerator Fabric: Michael Taylor Built in only 9 months. Celerity is an accelerator-centric SoC with a tiered accelertor fabric. Implemented in TSMC 16nm FFC. 25mm2 die area, 385M transistors Why 511 RISC-V cores? 5 Linux-capable RV64G Rocket cores, 496-core RV32IM mesh tiled area “manycore”, 10-core RV32IM mesh tiled array (low voltage).