Introduction of Technologies and People Supporting RISC-V Ecosystem RISC-Vエコシステムを構成する技術と立役者たち IEEE Micro51 RISC-V Day 2018 Fukuoka Saturday, October 20th 2018 09:45 - 10:00 FPGA Development Diary Author @msyksphinz_dev http://msyksphinz.hatenablog.com

Self Introduction “FPGA Development Diary” www.msyksphinz.hatenablog.com “RISC-V Blogger” @msyksphinz_dev Writing about technical topics such as RISC-V, FPGA, CPU- architecture, Deep Learning, Quantum Computing... on my blog. My work: Hardware Development Engineer Designing processors, and debugging chips and so on... I am employed even though I write blog posts everyday. CQ publishing, “Interface” Magazine “Research of RISC-V, open-source instruction set architecture” series I don’t know how to pronounce that... APS-web.jp RISC-V for Beginners

Introduction of technologies supporting RISC-V Eco-system • There are many technologies that support RISC-V • Software ecosystem • Hardware ecosystem • I will introduce various technologies, communities and tools.

Goal of Open-Hardware including RISC-V • Building communities where hardware design and CPU architecture can be openly discussed. • Example: Meltdown / Spectre • Example: Memory Consistency Model of RISC-V • A RISC-V memory consistency model problem has been found by university researchers. • Security topics are mainly discussed in RISC-V community today. • Keystone: open security platform based on RISC-V. More people can join to develop More people can join to discuss hardware development entry barrier goes down. More people become hardware developers Expands the range of Hardware developers

RISC-V open-source hardware / software is a chance for semiconductor industries • Mainstream CPU is x86 / Arm • But license fees are a problem while ever more money is required to use the latest process technology. • IP, EDA, Wafer manufacturing, packaging... • It is good to increase choices • We want to concentrate our “original” technologies, and reduce the effort for other parts (SoC, control CPU ...) • RISC-V is a good choice • Your own CPU core is hard to maintain only by yourself • GCC, Linux, toolchains, ... • Cutting costs by introducing RISC-V, including software ecosystem. • And RISC-V can solve the patent worries for your in-house developed CPU architecture. • Minimizing development cost of center of your SoC, the CPU • There are many other areas that require attention, not only the CPU. • We want to focus on the original and valuable parts in chips.

People and technologies that support “RISC-V Instruction Set Architecture” RISC-V Foundation Working Group GCC Binutils LLVM Linux QEMU ISS BOOM Rocket- Chip Freedom SoC HiFive1 HiFive Unleashed Board and platform SIMD Extension Privileged Spec Security Memory model Software toolchain Board of directors mainly leads RISC-V ISA, and there are many Working groups for each sub-topic … Linux Package maintainer OS import by volunteer Maintenance by Foundation Member Maintenance by Foundation Member Board of Directors RISC-V ISA Manual

Software Ecosystem ◼Almost all toolchains are finished to import ◼ GCC 7.1 merged RISC-V into mainstream. ◼ LLVM/Clang RISC-V support is progressing, lead by the lowRISC project ◼ Linux Kernel merged from version 4.15 ◼ Linux Distributions RISC-V support progress ◼ RedHat / Debian ◼ FreeBSD : RISC-V support progress ◼ QEMU v2.12 supports build for RISC-V32/64 ◼ RISC-V test pattern identifies “what is RISC-V” ◼ We have to pass these test patterns. • riscv-tests (https://github.com/riscv/riscv-tests) • riscv-torture (https://github.com/ucb-bar/riscv-torture)

Engineer communities supporting RISC-V • Anyone can join the RISC-V community • Google Groups(Mailing List) • You can get answers to various questions. Announcements Academic Community Software Developers Hardware Developers ISA Developers Debug • RISC-V Tags are prepared in Stack Overflow • SiFive Forum • Community for SiFive products and specifications. https://stackoverflow.com/questions/tagged/riscv https://forums.sifive.com https://riscv.org/mailing-lists/

GitHub Repositories support RISC-V • Software Toolchains / Hardware Toolchains Note: SW/HW status is summarized at https://riscv.org/software-status, https://riscv.org/risc-v-cores/ riscv-tools riscv-openocd riscv-fesvr riscv-gnu-toolchain riscv-isa-sim riscv-opcodes riscv-tests riscv-pk OpenOCD for RISC-V Front-end server for RISC-V Simulation Compiler and Libraries Instruction Set Simulator RISC-V Test patterns RISC-V Proxy Kernel https://github.com/riscv/riscv-tools https://github.com/esperantotech/boom-template https://github.com/ucb-bar/project-template

Hardware Ecosystem : Rocket-Chip/BOOM ZC706 ZedBoard Rocket-Chip BOOM Freedom-SoC HiFive1 HiFive Unleashed ASIC 4+1Core RV64 1GHz Arduino RV32 320MHz FPGA AWS

Power of RISC-V Open Ecosystem: Making RISC-V Simulator from scratch that can boot Linux • I want to understand RISC-V specification well. • I can’t understand by reading ISA manual only. Making RISC-V Simulator Target 1. Passing all test patterns Target 2. Boot Linux RISC-V Linux : Linux binary published at Freedom-U-SDK repository single Linux image built by buildroot. Kernel v4.15 Repository is at https://github.com/sifive/freedom-u-sdk Note: There are many open Linux distributions for RISC-V RedHat, Debian, ... This time, I’m using a single image version for simplicity.

Power of RISC-V Open Ecosystem: Making RISC-V Simulator from scratch that can boot Linux pk (proxy kernel) RISC-V Instruction Set Simulator dtb Device Tree Blob Target Program Elf Log Files x86 Host Linux Reference materials Note: pk(proxy kernel) Structures to handle system calls in place of the actual RISC-V It can pass on system calls such as printf() and file-system access on to the x86 host machine Note: PK is not used for booting Linux RISC-V ISA Spec Manual RISC-V Privileged Manual Implementation of riscv-isa-sim It is recommended to look into the simulator when you can't understand by only reading the manual. It faithfully reproduces the RISC-V spec by C++. GitHub address : http://github.com/msyksphinz/swimmer_riscv RISC-V Implementation reads device tree at initial phase of RISC-V boot

RISC-V's great aspects I learned while booting Linux ◼ All tools are open, easy debugging ◼ https://github.com/riscv/riscv-tools ◼ Simple Instruction Set! ◼ All test patterns are open: ◼ ISA test pattern riscv-tests / riscv-torture ◼ I want to implement some functions → Anyway I can run regression test using riscv-tests to validate my implementation. ◼Test patterns for RISC-V ◼ RISC-V implementations should pass these tests. ◼ riscv-tests (https://github.com/riscv/riscv-tests) ◼ riscv-torture (https://github.com/ucb-bar/riscv-torture)

• Try RISC-V by checking out an open source RISC-V core • You can start RISC-V even if you don’t have much money • Support for RISC-V ISA in hardware / software is steadily progressing. • Many ways to try RISC-V • Using FPGA Board : customize a design and run it on a FPGA. • Buy an evaluation board: evaluate your application easily. • Everyone has a chance! • If you can't find what you want, you and make it yourself and publish it on the internet. • Your contribution makes RISC-V community bigger. Summary: Everyone can join RISC-V communities If you are interested in RISC-V, You can join now. If more people join the effort, RISC-V will become more interesting.