Nordic Semiconductor CTO Svein-Egil Nielsen has penned a piece detailing the company's thinking on jumping on the RISC-V bandwagon — something which it argues complements, rather than competes with, its existing relationship with proprietary chip IP giant Arm.
"At first glance, Nordic announcing that it is putting its full technological and commercial weight behind the development and adoption of an open source chip architecture might raise questions about how strong the company's on-going relationship with Arm is," Nielsen admits in the article. "After all, Arm provides a commercial chip architecture that is anything but open source, and has been used on Nordic's semiconductor wireless connectivity products since the 2012 launch of Nordic's nRF51 Series Systems-on-Chip (SoCs)."
Nordic announced its interest in the free and open source RISC-V instruction set architecture (ISA) back in August, jumping in with both feet by announcing the formation of a joint venture with Bosch, Infineon, NXP Semiconductors, and Qualcomm Technologies. The quintet of industry heavyweights are in the process of forming a German company which aims to accelerate the commercialization of the platform and its software ecosystem — beginning with its use in the automotive market and expanding to the Internet of Things (IoT) and mobile in due course.
Scaling from low-power microcontrollers all the way to many-core supercomputers, the RISC-V instruction set architecture is free and open source — nobody has to sign any non-disclosure agreements, pay large sums in licensing or royalties, or even obtain permission to begin building around it. While all of that would seem to spell trouble for industry giant Arm, whose income is driven solely by licensing and royalty payments on its processor cores and other intellectual properties (IPs), Nielsen says there's room for both.
"I see RISC-V in a similar way to how I see the proliferation of wireless IoT connectivity standards: no one technology can be all things to (solve) all application problems. So does Bluetooth LE really compete with Thread or cellular IoT? Of course not. Each is designed to do different things well, but not everything," Nielsen argues. "What RISC-V is in reality, therefore, is a complimentary alternative to Arm, and not a threat. And this is particularly true in power consumption-critical mobile and IoT applications where Arm has traditionally been dominant."
Nielsen claims Nordic's interest in RISC-V is primarily in offering customers' "freedom and flexibility" in paring down the features of the modular ISA in order to get as low a power draw as possible — but that it will be limited to "certain specific and highly specialized applications." This stance is the opposite of that taken by rival Espressif, which announced two years ago that it would be moving to RISC-V as standard for all future parts "unless," as chief executive officer and president Teo Swee Ann said at the time, "we have some special needs."
"So where might the ability to develop an ultra lowest power instruction set really come into its own? To me it's at the edge in, for example, simpler embedded chips for sensors that require a small bit of processing power in order to deliver localized machine learning," Nielsen says. "In such applications having an Arm core would be complete overkill. But that sensor may still need to communicate with and work alongside an Arm core-based Nordic device.
"What RISC-V will not do is conflict with Nordic's long-established use of Arm cores in its wireless IoT connectivity devices."
Nielsen's full argument is laid out over on the Nordic blog.