NASA has chosen the technology to help it land future spacecraft on unmapped planets. Meta uses the technology for artificial intelligence. Chinese engineers have turned to it to encrypt data.
And it could represent the next front in the semiconductor trade war between the United States and China.
The technology is RISC-V, pronounced “risk five.” It evolved from a university computer lab in California to a foundation for myriad chips that handle computing chores. RISC-V essentially provides a kind of common language for designing processors that are found in devices like smartphones, disk drives, Wi-Fi routers and tablets.
RISC-V has ignited a new debate in Washington in recent months about how far the United States can or should go as it steadily expands restrictions on exporting technology to China that could help advance its military. That’s because RISC-V, which can be downloaded from the internet for free, has become a central tool for Chinese companies and government institutions hoping to match U.S. prowess in designing semiconductors.
Last month, the House Select Committee on the Chinese Communist Party — in an effort spearheaded by Representative Mike Gallagher, Republican of Wisconsin — recommended that an interagency government committee study potential risks of RISC-V. Congressional aides have met with members of the Biden administration about the technology, and lawmakers and their aides have discussed extending restrictions to stop U.S. citizens from aiding China on RISC-V, according to congressional staff members.
The Chinese Communist Party is “already attempting to use RISC-V’s design architecture to undermine our export controls,” Representative Raja Krishnamoorthi of Illinois, the ranking Democrat on the House select committee, said in a statement. He added that RISC-V’s participants should be focused on advancing technology and “not the geopolitical interests of the Chinese Communist Party.”
Arm Holdings, a British company that sells competing chip technology, has also lobbied officials to consider restrictions on RISC-V, three people with knowledge of the situation said. Biden administration officials have concerns about China’s use of RISC-V but are wary about potential complications with trying to regulate the technology, according to a person familiar with the discussions. The Department of Commerce and the National Security Council declined to comment.
The debate over RISC-V is complicated because the technology was patterned after open-source software, the free programs like Linux that allow any developer to view and modify the original code used to make them. Such programs have prompted multiple competitors to innovate and reduce the market power of any single vendor.
But RISC-V is not code that can directly be used to make anything. It is a set of basic computing instructions that determine the calculations a chip can perform. Engineers can download these instructions and incorporate them in the much more complex task of creating design blueprints for parts of a semiconductor. Many companies sell RISC-V chip designs, and some universities and other institutions distribute them free.
As with Linux — but not technologies from companies like Arm and Intel — engineers around the world can make suggestions to enhance the underlying instructions. That process is overseen by RISC-V International, a nonprofit with more than 4,000 members — including the Chinese Academy of Sciences and Chinese firms like Huawei and Alibaba, as well as Google and Qualcomm — in 70 countries.
The group changed its incorporation from the United States to Switzerland in 2020 to calm “concerns of political disruption” and control by any single country. Its leaders said their model mirrored that of other international groups that govern standard technologies like Ethernet and Wi-Fi.
“Open standards have been around for 100 years,” Calista Redmond, chief executive of RISC-V International, said in an interview. “This is no different.”
Open-source technologies have generally been granted exceptions to U.S. export controls. Any change to that treatment “is certainly going to raise thorny legal issues and important public policy concerns,” said Daniel Pickard, a lawyer specializing in trade and national security at Buchanan Ingersoll & Rooney.
U.S. regulations limit Arm and RISC-V companies from exporting chip designs to China based on certain performance limits. But trying to restrict the underlying instructions is like trying to control words or letters, Silicon Valley executives said.
“It is absolutely silly,” said Dave Ditzel, the chief technology officer of Esperanto Technologies, a chip start-up that uses RISC-V. “It’s like saying, ‘Well, the Chinese can read a book on nuclear weapons that’s written in English, so let’s solve the problem by banning the English alphabet.’”
As RISC-V helps Chinese firms including Huawei design more of the world’s semiconductors, some U.S. officials have raised concerns that Beijing could use Chinese foundries to insert cyber vulnerabilities into chips that may be used to cripple American electrical grids and other critical infrastructure.
RISC-V backers counter that technologies with inner details that can be openly studied are much more secure. Any new restrictions, RISC-V backers said, would weaken U.S. influence over the technology while doing little to hold China back because the instruction set is already widely distributed.
The original inspiration for RISC-V was saving money. Starting in 2010, a professor and two graduate students began developing a new instruction set based on technology pioneered by David Patterson, a computer science professor at the University of California, Berkeley, who had helped invent reduced instruction set computing, or RISC. The aim was to help study the inner workings of computing without having to pay Arm, which charges royalties for every chip that uses its technology.
“I just wanted to learn how to build computers,” said Yunsup Lee, one of the graduate students, who now works at SiFive, a start-up that sells RISC-V designs. Then the goal evolved “to benefit everybody in the world,” he said.
The RISC-V variant swiftly attracted interest among engineers. Having a standard set of instructions can allow software programs to work on all chips that use them.
In China, engineers and officials were also quick to see the potential, viewing open-source technology as a way to become self-sufficient and counter risks like embargoes and supply interruptions, Ni Guangnan, a researcher at the Chinese Academy of Sciences, wrote in an article about RISC-V in June.
In 2019, Mr. Patterson, who now works at Google, helped establish a RISC-V lab in Shenzhen, China, which was supported by an institute set up earlier by Berkeley and Tsinghua University in China. Representative Gallagher, in a video his committee released in November, expressed concerns about the professor’s work and collaboration between the institute and organizations with links to Chinese military and intelligence activities.
Mr. Patterson declined to comment through a Google spokeswoman.
A U.C. Berkeley spokesman said that the university’s work with the institute had been basic research that was unrestricted, and that the university was responding to requests for information from Congress.
More than 100 “significant” Chinese companies are designing chips with RISC-V today, as are at least 100 more start-ups, said Handel Jones, an analyst at International Business Strategies. Many of the applications are in fairly mundane consumer products, but engineers believe the technology will eventually take over some of the most demanding tasks.
Chinese aerospace scientists have proposed using RISC-V to develop high-performance spaceborne computers. Other Chinese companies and institutions are aiming to string together RISC-V processors to run bigger jobs in data centers, including A.I. applications.
At a RISC-V conference in Silicon Valley in November, T-Head, Alibaba’s semiconductor subsidiary, discussed RISC-V designs that Sophgo, another Chinese company, used in a chip powering a large server deployed at Shandong University in China. It’s the first instance of RISC-V technology’s running a cloud-style computing service, the companies said.
“We just made a small step, but we put RISC-V on the starting line,” David Chen, ecosystem director at Alibaba, said at the event.