AMD pulled the plug on developing its own Arm cores after he left the company, according to chip designer Jim Keller. He calls it a stupid decision. Around 2014 AMD had plans for server processors based on Arm cores and the plan to make its own Arm cores.
Keller worked at AMD on the first, second, and third generation Zen cores. He recently told a conference that he noted at the time that the cache design for Arm and x86 CPUs is largely the same, as are many other parts. The difference in the processor architectures is mainly in the decoder unit.
Because of the similarities, Keller’s team began work on its own Arm core codenamed K12. AMD had bought a license for this from Arm. “They stupidly canceled that project,” Keller said in his Future of Compute presentation. According to Keller, “certain executives” at AMD scrapped the project after his departure, because they were “afraid of change.”
AMD planned to use Arm cores for server processors, also in combination with x86 processors. In 2014, the processor maker presented plans for server processors based on existing Arm cores. The own Arm cores were also put on the roadmap for 2016. That was later postponed to 2017, but it never came to that. A year after the presentation, AMD canceled the Arm plans.
Instead of Arm cores, AMD now uses x86 cores based on the Zen architecture in its EPYC server processors. The manufacturer is currently having great success with this. EPYC processors are currently found in the fastest supercomputer in the world. Five out of ten fastest systems in the top 500 supercomputers list are equipped with EPYC processors.
AMD’s K12 Project
Keller worked at AMD, Intel, Apple, Tesla and more
Jim Keller has a long track record and is considered one of the foremost designers of processor microarchitectures. He worked at DEC on Alpha processors in the 1980s and moved to AMD in 1998 to work on the Athlon processors. A year later, he moved to SiByte to work on MIPS processors. That company was acquired by Broadcom. Beginning in 2004, Keller held a top position at PA Semi, the company that Apple hired in 2008 to make its own socs for iPhones.
Keller worked at Apple until 2012 and then returned to AMD, where he worked on the Zen architecture and the K12 project for Arm processors. In 2016, he joined Tesla to work on AI chips for the Autopilot hardware. In 2018 he made the switch to Intel, where he left again in 2020. Keller is currently the CTO of Tenstorrent, a start-up working on AI chips.