While it’s not going to displace even a Raspberry Pi Model B+ in terms of performance, it’s a start. Things will only get better and faster from here.
At long last, after years and years of waiting, there’s an open source CPU chip already built onto a development board that you can buy and use. The $59 price is very affordable. This matters as the various main line CPU vendors have been pressured into putting ever more weaknesses ( i.e. what looks like potential back doors) into their hardware for various government TLAs (Three Letter Agencies).
So what’s the base project / CPU design group?
RISC-V (pronounced “risk-five”) is an open instruction set architecture (ISA) based on established reduced instruction set computing (RISC) principles.
In contrast to most ISAs, the RISC-V ISA can be freely used for any purpose, permitting anyone to design, manufacture and sell RISC-V chips and software. While not the first open ISA, it is significant because it is designed to be useful in modern computerized devices such as warehouse-scale cloud computers, high-end mobile phones and the smallest embedded systems. Such uses demand that the designers consider both performance and power efficiency. The instruction set also has a substantial body of supporting software, which fixes a usual weakness of new instruction sets.
The project began in 2010 at the University of California, Berkeley, but many contributors are volunteers and industry workers outside the university.
The RISC-V ISA has been designed with small, fast, and low-power real-world implementations in mind, but without over-architecting for a particular microarchitecture style.
The RISC-V authors aim to provide several CPU designs freely available under a BSD license. Such licenses allow derivative works, such as RISC-V chip designs, to be either open and free, like RISC-V itself, or closed and proprietary.
SiFive has developed an embedded system on chip, compatible with Arduino, for sale at $59 that began selling in May 2017.
Codasip and UltraSoC have developed fully supported intellectual property for RISC-V embedded SOCs that combine Codasip’s RISC-V cores and other IP with UltraSoC’s debug, optimization and analytics.
Imperas has developed a family of fast processor models for the different subsets of RV32G and RV64G ISA variants that are part of the OVPsim instruction accurate simulator distributions used for embedded software development.
The Indian Institute of Technology Madras is developing six RISC-V open-source CPU designs for six distinct uses, from a small 32-bit CPU for the internet of things (IoT) to large, 64-bit CPUs designed for warehouse-scale computers such as server farms based on RapidIO and Hybrid Memory Cube technologies.
Nvidia plans to use RISC-V to replace their Falcon processor on their GeForce graphics cards.
ASTC in Adelaide developed a RISC-V CPU for embedded ICs.
A founder of Adapteva plans to use RISC-V, in a successor to their manycore accelerator product
lowRISC is a non profit project that aims to implement a fully open-source system on a chip (SoC) based on the 64-bit RISC-V ISA.
The Computer Laboratory, University of Cambridge, in collaboration with the FreeBSD Project, has ported the FreeBSD operating system to 64-bit RISC-V to use as a hardware-software research platform.
ETH Zurich and the University of Bologna have cooperatively developed the PULPino processor as part of the PULP (Parallel Ultra-Low Power) project using RISC-V
So the “in development” is interesting in terms of a list of dreams. Server farms made of 64 bit CPUs, all provably non-buggered from the design stage. But what about NOW?
Well, that’s the first line. SiFive has a devo board you can buy today. The specs make it usable in small embedded systems and robotics, but a bit too light for even a command line only desktop. For now…
SiFive is a fabless semiconductor company that produces computer chips based on the RISC-V instruction set architecture (ISA) SiFive’s products include SoC’s and development boards.
SiFive is the first company to produce a chip that implements that RISC-V ISA.
SiFive was founded in 2015 by Krste Asanovic, Yunsup Lee, and Andrew Waterman, three researchers from the University of California Berkeley. On November 29, 2016, SiFive released the Freedom Everywhere 310 SoC and the HiFive development board, making SiFive the first company to produce a chip that implements that RISC-V ISA, although universities have produced earlier RISC-V processors.
In August 2017, SiFive hired Naveed Sherwani as CEO. In October, SiFive did a limited release of its U54-MC, reportedly the world’s first RISC-V based 64-bit quad-core CPU to support fully featured operating systems like Linux.
SiFive’s business model is based on designing custom computer chips for other businesses. SiFive also produces the FE310 microcontroller and the HiFive1 development board.
OK, so quad core 64 bit sounds good. What’s that full up board?
A RISC-V-based, Open-Source, Arduino-Compatible Development Kit
The HiFive1 is an Arduino-Compatible development kit featuring the Freedom E310, the industry’s first commercially available RISC-V SoC.
HiFive1 Features & Specifications
Microcontroller: SiFive Freedom E310 (FE310)
SiFive E31 RISC-V Core
Architecture: 32-bit RV32IMAC
Speed: 320+ MHz
Performance: 1.61 DMIPs/MHz, 2.73 Coremark/MHz
Memory: 16 KB Instruction Cache, 16 KB Data Scratchpad
Other Features: Hardware Multiply/Divide, Debug Module, Flexible Clock Generation with on-chip oscillators and PLLs
Operating Voltage: 3.3 V and 1.8 V
Input Voltage: 5 V USB or 7-12 VDC Jack
IO Voltages: Both 3.3 V or 5 V supported
Digital I/O Pins: 19
PWM Pins: 9
SPI Controllers/HW CS Pins: 1/3
External Interrupt Pins: 19
External Wakeup Pins: 1
Flash Memory: 128 Mbit Off-Chip (ISSI SPI Flash)
Host Interface (microUSB): Program, Debug, and Serial Communication
Dimensions: 68 mm x 51 mm
Weight: 22 g
OK, so they have two chips with similar “Freedom” names, but one is 32 bit on the board and the other is a quad core 64 bit… The board runs at 320 MHz, so not a barn burner. Figure it’s about 1/2 of a Pi B+ as a first guess. (Comparing actual benchmarks would be better, so a Dig Here! is to look up DMIPs and Coremark numbers for the Pi.)
Interface is via microUSB, so not going to plug in your HDMI monitor and go… Clearly the market for this is things like small routers, home WiFi hotspots, and DIY cellphones. Oh, and things like robotics and process / device controllers. Not desktops…
Lists there SOC products. The fastest one looks very interesting to me:
The Freedom Unleashed family features a series of customizable Unix-capable SoC platforms, based on SiFive’s U5 Core IP Series, the world’s most advanced multicore RISC-V CPUs. The first member of the Freedom Unleashed family, the U500 platform targets initial customers in diverse markets such as machine learning, storage, and networking.
Freedom U500 Platform
U5 Core IP Series at 1.6GHz+
Multicore, Cache Coherency Support
High Speed Peripherals: PCIe 3.0, USB3.0, GbE, DDR3/4
Multicore at 1.6 GHz we’re getting somewhere very interesting. GbE and USB 3.0 are nice too.
Unfortunately, the dev kit for it is a FPGA (Field Programmable Gate Array) and not a real CPU chip, so speed is not going to be the same, nor costs:
Freedom U500 VC707 FPGA Dev Kit
The Freedom U500 VC707 FPGA Dev Kit is the most powerful way to prototype and develop for RISC-V. Featuring SiFive’s U5 Core IP Series, the world’s most advanced RISC-V CPU, this kit is the ideal way to start developing advanced OS capabilities and software applications. This development kit also features high speed serial interfaces allowing for system prototyping with PCIe, USB, or GbE interfaces.
The VC707 FPGA Dev Kit consists of the Xilinx Virtex-7 FPGA VC707 Evaluation Kit plus many optional components.
Clicking their “BUY” link takes you to Avnet where you can buy one for a “mere” $3500…
Your Price: USD $3,495.00
Lead time: 2 weeks
The Virtex®-7 FPGA VC707 Evaluation Kit is a full-featured, highly-flexible, high-speed serial base platform using the Virtex-7 XC7VX485T-2FFG1761C and includes basic components of hardware, design tools, IP, and pre-verified reference designs for system designs that demand high-performance, serial connectivity and advanced memory interfacing. The included pre-verified reference designs and industry-standard FPGA Mezzanine Connectors (FMC) allow scaling and customization with daughter cards.
VC707 evaluation board featuring the Virtex-7 XC7VX485T-2FFG1761C FPGA
Full seat Vivado® Design Suite: Design Edition
Node locked & Device-locked to the Virtex-7 XC7VX485T FPGA, with 1 year of updates and support
Getting Started Guide (Web)
Board Design Files (DxDesigner 2005, Allegro 16.3 – 16.5)
AMS 101 evaluation board
Cables & Power Supply
90-day limited warranty
40Gb/s Connectivity platform for high-bandwidth and high-performance applications using Virtex-7 VX485T FPGAs
Hardware, design tools, IP, and pre-verified reference designs
Advanced memory interface with 1GB DDR3 SODIM Memory up to 800MHz / 1600Mbps
Enabling serial connectivity with PCIe Gen2x8, SFP+ and SMA Pairs, UART, IIC
Supports embedded processing with MicroBlaze, soft 32bit RISC
Develop networking applications with 10-100-1000 Mbps Ethernet (GMII, RGMII and SGMII)
Expand I/O with the FPGA Mezzanine Card (FMC) interface
Well, at that price I guess I’m going to wait for that motivation to set up a Kickstarter Campaign to kick in ;-)
At least it’s a start. Somewhere someone will be getting one of these and launching a Kickstarter to make a Pi Like Board but without the licenses and opaque binary blobs. It will sell. (I’ll buy one up to $100, maybe more…)
I’d guess the ‘lead time’ is about 2 years from now to first product. Faster if well funded.
At that point, you have Free and Open Source from hardware to desktop. Major remaining risks would just be who does the actual fab and do they stick in something unexpected / clandestine. As these are boards going to low level developers, I’d expect “oddities” to stand out “right quick”. Someone, somewhere, will dump and disassemble any firmware. Someone in QA somewhere will SEM (Scanning Electron Microscope) some die and see what’s really been fabbed. Even if it’s just a grad student doing it as a project for extra credit.
So I’m marking my calendar. Sometime around 2019 I’ll be expecting to put one of these, as a SOC (System On Chip) based SBC (Single Board Computer), on my desktop, and boot Devuan.
I have a friend who teaches robotics. I might buy him the $59 board as a Christmas present… then get him to teach me how to use it in robots ;-)