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arXiv · 2110.10857

Vortex: Extending the RISC-V ISA for GPGPU and 3D-GraphicsResearch

Blaise Tine·Fares Elsabbagh·Krishna Yalamarthy·Hyesoon Kim
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Abstract

The importance of open-source hardware and software has been increasing. However, despite GPUs being one of the more popular accelerators across various applications, there is very little open-source GPU infrastructure in the public domain. We argue that one of the reasons for the lack of open-source infrastructure for GPUs is rooted in the complexity of their ISA and software stacks.In this work, we first propose an ISA extension to RISC-V that supports GPGPUs and graphics. The main goal of the ISA extension proposal is to minimize the ISA changes so that the corresponding changes to the open-source ecosystem are also minimal, which makes for a sustainable development ecosystem. To demonstrate the feasibility of the minimally extended RISC-V ISA, we implemented the complete software and hardware stacks of Vortex on FPGA. Vortex is a PCIe-based soft GPU that supports OpenCL and OpenGL.Vortex can be used in a variety of applications, including machine learning, graph analytics, and graphics rendering. Vortex can scale up to 32 cores on an Altera Stratix 10 FPGA, delivering a peak performance of 25.6 GFlops at 200 Mhz.

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Blaise Tine, Fares Elsabbagh, Krishna Yalamarthy, Hyesoon Kim. 2021-10-21. Vortex: Extending the RISC-V ISA for GPGPU and 3D-GraphicsResearch. https://arxiv.org/abs/2110.10857

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