RISC-V+GPU，SiFive重磅宣布

Core Viewpoint - SiFive, a leading company in the RISC-V space, is now supporting NVIDIA's proprietary NVLink Fusion interconnect technology, raising questions about the viability of its competitor UALink technology [1][2]. Group 1: SiFive and NVLink Fusion - SiFive designs CPU cores and processors based on the RISC-V instruction set architecture (ISA), applicable in various scenarios from edge computing to data centers, and licenses its designs to customers [1]. - The announcement indicates that SiFive's designs will now include support for NVLink, which allows NVIDIA's customers to abstract an entire CPU and GPU as a unified accelerator, providing up to 3.6 TB/s of inter-chip bandwidth [1][2]. - SiFive's CEO, Patrick Little, stated that the adoption of NVLink Fusion reflects a shift in the industry towards heterogeneous, collaborative design systems, where open CPU architectures and advanced interconnect technologies define the future of AI data center computing [2]. Group 2: Industry Support and Developments - Major companies such as Intel, Arm, and Qualcomm are fully supporting NVLink Fusion, with Intel planning to release client systems that connect its CPU chips with NVIDIA's GPU chips using this technology [2]. - NVIDIA supports two configurations of NVLink Fusion: one that combines partner CPUs with NVIDIA GPUs, and another that allows customers to integrate NVIDIA's Grace or Vera CPUs with their custom XPU or AI accelerators [2]. - SiFive is focused on helping its customers build custom CPUs using its cores and reference designs for SoCs integrated with NVIDIA CPUs [3]. Group 3: UALink Technology Challenges - UALink was initially envisioned as an open alternative to NVLink, supported by numerous companies including Intel, AMD, Amazon, Meta, Microsoft, and Arm; however, establishing the standard has proven difficult [4]. - The lack of UALink switches has forced AMD to transmit the protocol through standard Ethernet tunnels, complicating the implementation [4]. - Broadcom, once a strong supporter of UALink, is now promoting its own interconnect architecture called Scale Up Ethernet (SUE) [4].