comment As Qualcomm tries to fend off a lawsuit from Arm demanding that Qualcomm destroy its custom cores, the Snapdragon giant has signaled it could have a brighter future with RISC-V.
And all while Qualcomm criticized an “existing legacy architecture” for having useless features and not meeting certain requirements.
At this week’s RISC-V Summit, Manju Varma, Qualcomm director of product management, said that RISC-V, an emerging alternative to the proprietary ARM instruction set architecture, offers opportunities for a range of devices that Qualcomm is developing chips for, from wearables and Smartphones to laptops and connected cars.
Qualcomm launches the latest Arm-powered Snapdragon chip amid a bitter licensing battle
While Qualcomm continues to use Arm’s instruction set architecture (ISA) and off-the-shelf CPU designs as the basis for the application processing cores in its system-on-chips (SoC), the US giant turned to RISC-V within its chips for microcontroller cores, starting with the Snapdragon 865 SoC in 2019, according to Varma, which is helping drive Qualcomm’s CPU strategy and roadmap across the company’s entire portfolio.
According to Varma, the Snapdragon giant is now using RISC-V microcontrollers in SoCs in PCs, mobile devices, wearables, connected cars, and augmented reality and virtual reality headsets. These microcontrollers perform low-level work in the background, e.g. B. managing hardware.
This has led to Qualcomm appearing to have shipped more than 650 million RISC-V cores to date, making the ISA “one of the core technologies for Qualcomm” and Qualcomm “one of the leading providers of RISC-V implementations”.
We note that Qualcomm is a founding member of RISC-V International, the body that oversees the open-source, royalty-free ISA, so its support and enthusiasm for RISC-V comes as no surprise.
The Qualcomm executive added that RISC-V offers opportunities for higher-value use cases than microcontrollers.
“With a common base instruction set architecture that scales from low-end microcontrollers to high-performance computing and everything in between, it truly enables efficiencies across the industry,” Varma said in her keynote.
The Claimed Benefits of RISC-V Over “Legacy Architecture”
Qualcomm first turned to RISC-V for a microcontroller in the Snapdragon 865 because they “needed something that was customizable, met our unique needs, and had a small footprint,” says Varma. One thing about RISC-V is that it can be extended by CPU core implementers with custom instructions and functions.
“The solutions from the existing legacy architecture did not meet these requirements,” she added.
According to Varma, the main advantage of RISC-V is that it receives feature contributions from different companies and organizations at all layers of the “value chain”, from ISA and CPU to system software, operating system and end-user applications. This is in contrast to legacy architecture, which is “owned by an entity in the value chain,” she added.
The contribution structure for RISC-V, enabled by its open-source nature and managed by the non-profit organization RISC-V International, creates an “opportunity to add features that provide value to end users [and] be defined together with everyone in this value chain,” says Varma.
This is another area where legacy architecture has fallen short, she added.
“Now, a lot of times in the past we’ve seen legacy architecture introduce features that didn’t seem to bring any real value to end users,” Varma said.
With RISC-V there is an opportunity to define chip designs that have “best-in-class performance, power efficiency and value-added features,” she said.
So wait, is Arm the “legacy architecture”?
In the three times that Varma referred to this “ancient architecture,” she did not refer to it by name. While we can’t definitively say she’s talking about Arm, there are some good reasons to believe she is:
- Qualcomm has historically been a major licensee of Arms ISA and off-the-shelf chip designs.
- Arm has claimed that it is a dominant player in the microcontroller space, with its Cortex-M designs accounting for nearly three-quarters of Arm-based chip shipments each year.
- Varma compared RISC-V to legacy architecture in the context of an ISA that can scale from microcontrollers to high-performance computers, demonstrating Arm’s breadth of capabilities. So we don’t think she was talking about the many other ISAs that exist for microcontrollers. And we didn’t get the impression she was talking about x86.
Then there’s the fact that Arm is suing Qualcomm to try and destroy the latter’s custom Nuvia cores, which are designed to be compatible with the former’s ISA.
Arm believes Qualcomm’s custom cores should be destroyed because Arm believes the Snapdragon giant failed to negotiate a new architecture license agreement after acquiring startup Nuvia, where development of the cores began, in 2021.
Qualcomm, on the other hand, argues that it can continue developing the custom cores because it has an existing architecture license with Arm that “broadly overlaps” with the one Nuvia had.
While Qualcomm hasn’t said what it will do if it loses the lawsuit, several analysts have said the lawsuit gives companies more reason to consider RISC-V as an alternative to Arm, regardless of whether Arm wins or not .
However, as noted, Qualcomm’s interest in RISC-V isn’t new. The company began using RISC-V for microcontrollers in products in 2019, and in the same year invested in SiFive, a RISC-V chip designer that competes with Arm.
According to Varma, RISC-V needs improvement
While Varma spent much of her keynote advocating the benefits of RISC-V, she issued a call to the developer community surrounding the ISA, saying that contributors needed to work on standardizing features and reducing fragmentation, a known issue among developers.
Arm Qualcomm’s Snapdragon launch party with the latest salvo in the license war
“As a silicon vendor, we see a need for standardized, RISC-V compliant system IPs. We see many innovations in the area of application processors. We see a lot of diversity, competition, differentiation, and that’s great. But we need to make sure we standardize system IPs to reduce ecosystem fragmentation,” Varma said.
The Qualcomm executive said the RISC-V community needs to ensure they don’t fall back on features marketed for the ISA.
Varma added more wishlist items for RISC-V:
If the RISC-V community developed a “best-in-class architecture specification” for security, machine learning, and AI, and introduced new features faster, the ISA ecosystem would have “a tremendous time-to-market advantage,” concluded Varma. ®
https://www.theregister.com/2022/12/15/qualcomm_talks_up_riscv_roasts/ Qualcomm Talks RISC-V, Toasts “Legacy Architecture” • The Register