**QEMU/RISCV64 VIRT Board Support Package User Guide** English | [中文](./README_cn.md) - [1. Introduction](#1-introduction) - [2. Building](#2-building) - [2.1. Installing the toolchain](#21-installing-the-toolchain) - [2.2. Setting RT-Thread toolchain environment variables](#22-setting-rt-thread-toolchain-environment-variables) - [2.3. Downloading the kernel](#23-downloading-the-kernel) - [2.4. Configuring the kernel](#24-configuring-the-kernel) - [2.5. Compiling the kernel](#25-compiling-the-kernel) - [3. Running](#3-running) - [3.1. Installing QEMU](#31-installing-qemu) - [3.2. Running QEMU](#32-running-qemu) - [4. How to use rv64ilp32 toolchain](#4-how-to-use-rv64ilp32-toolchain) - [5. Contact information](#5-contact-information) # 1. Introduction RISC-V is an open and free instruction set architecture (ISA). This project is a port on the RISCV64 VIRT version of QEMU. This project supports the world's first rv64ilp32 product-level open source toolchain jointly launched by the Xuantie team and the Institute of Software of the Chinese Academy of Sciences. # 2. Building Working system: take Ubuntu 22.04 as an example: ```shell $ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 22.04.2 LTS Release: 22.04 Codename: jammy ``` ## 2.1. Installing the toolchain The specific toolchain used is consistent with the official RT-Thread. For the specific toolchain version, please refer to the file in the RT-Thread repository. ```yaml - name: Install RISC-V ToolChains if: ${{ matrix.legs.QEMU_ARCH == 'riscv64' && matrix.legs.UTEST != 'rtsmart/riscv64' && success() }} run: | wget -q https://github.com/RT-Thread/toolchains-ci/releases/download/v1.4/riscv64-unknown-elf-toolchain-10.2.0-2020.12.8-x86_64-linux-ubuntu14.tar.gz sudo tar zxvf riscv64-unknown-elf-toolchain-10.2.0-2020.12.8-x86_64-linux-ubuntu14.tar.gz -C /opt /opt/riscv64-unknown-elf-toolchain-10.2.0-2020.12.8-x86_64-linux-ubuntu14/bin/riscv64-unknown-elf-gcc --version echo "RTT_EXEC_PATH=/opt/riscv64-unknown-elf-toolchain-10.2.0-2020.12.8-x86_64-linux-ubuntu14/bin" >> $GITHUB_ENV - name: Install RISC-V Musl ToolChains if: ${{ matrix.legs.QEMU_ARCH == 'riscv64' && matrix.legs.UTEST == 'rtsmart/riscv64' && success() }} shell: bash run: | wget -q https://github.com/RT-Thread/toolchains-ci/releases/download/v1.7/riscv64-linux-musleabi_for_x86_64-pc-linux-gnu_latest.tar.bz2 sudo tar xjf riscv64-linux-musleabi_for_x86_64-pc-linux-gnu_latest.tar.bz2 -C /opt /opt/riscv64-linux-musleabi_for_x86_64-pc-linux-gnu/bin/riscv64-unknown-linux-musl-gcc --version echo "RTT_EXEC_PATH=/opt/riscv64-linux-musleabi_for_x86_64-pc-linux-gnu/bin" >> $GITHUB_ENV echo "RTT_CC_PREFIX=riscv64-unknown-linux-musl-" >> $GITHUB_ENV ``` Among them, `riscv64-unknown-elf-gcc` is used to build the RT-Thread Standard version, and `riscv64-unknown-linux-musl-gcc` is used to build the RT-Thread Smart version. Download them to your local computer according to the links shown above and decompress them. ## 2.2. Setting RT-Thread toolchain environment variables There are three environment variables related to the RT-Thread toolchain - `RTT_CC` is the toolchain name, which is `"gcc"` here - `RTT_CC_PREFIX`: is the toolchain prefix, which is `"riscv64-unknown-elf-"` for the Standard version and `"riscv64-unknown-linux-musl-"` for the Smart version. - `RTT_EXEC_PATH`: the path where the bin folder of the toolchain is located, such as `"$HOME/tools/riscv64-unknown-elf-toolchain-10.2.0-2020.12.8-x86_64-linux-ubuntu14/bin"`. This is set according to the actual path after personal download and decompression. Note that the toolchains of the RT-Thread standard version and the Smart version are two different versions, and the path name of `RTT_EXEC_PATH` must be set to `bin`. If you use them all the time, it is recommended to export these three environment variables in the `.bashrc` file. ## 2.3. Downloading the kernel Assume that the working path is `$WORKSPACE`. ```shell $ cd $WORKSPACE $ git clone git@github.com:RT-Thread/rt-thread.git ``` **Note: This document is based on the kernel version git commit ID: ebe2926cd6.** Enter the BSP directory where qemu-virt64-riscv is located. The following operations will not be introduced separately. By default, it is in this directory. ```shell $ cd $WORKSPACE/rt-thread/bsp/qemu-virt64-riscv ``` ## 2.4. Configuring the kernel Refresh the configuration file before compiling for the first time. ```shell $ scons --menuconfig ``` The default configuration is the RT-Thread standard version, so if you don't have any special requirements, don't change anything, just save and exit. If you want to use the RT-Thread Smart version, at least turn on the `RT_USING_SMART` option after entering the configuration menu (see the figure below), and the rest depends on your needs. ``` (Top) → RT-Thread Kernel RT-Thread Project Configuration (24) The maximal size of kernel object name [ ] Use the data types defined in ARCH_CPU [*] Enable RT-Thread Smart (microkernel on kernel/userland) [ ] Enable RT-Thread Nano ... ``` Save and exit after modification. ## 2.5. Compiling the kernel If you have compiled before, you can clean it up: ```shell $ scons --clean ``` Or compile directly: ```shell $ scons -j$(nproc) ``` The kernel binary file `rtthread.bin` will be generated in the `$WORKSPACE/rt-thread/bsp/qemu-virt64-riscv`. # 3. Running ## 3.1. Installing QEMU ```shell $ sudo apt update $ sudo apt install qemu-system-misc ``` After the installation is complete, you can check the version. ```shell $ qemu-system-riscv64 --version QEMU emulator version 6.2.0 (Debian 1:6.2+dfsg-2ubuntu6.24) Copyright (c) 2003-2021 Fabrice Bellard and the QEMU Project developers ``` ## 3.2. Running QEMU The repository has provided a ready-made execution script, which can be executed directly: ```shell $ ./qemu-nographic.sh ``` The running results of the RT-Thread Standard version are as follows: ```shell $ ./qemu-nographic.sh OpenSBI v0.9 ____ _____ ____ _____ / __ \ / ____| _ \_ _| | | | |_ __ ___ _ __ | (___ | |_) || | | | | | '_ \ / _ \ '_ \ \___ \| _ < | | | |__| | |_) | __/ | | |____) | |_) || |_ \____/| .__/ \___|_| |_|_____/|____/_____| | | |_| Platform Name : riscv-virtio,qemu Platform Features : timer,mfdeleg Platform HART Count : 1 Firmware Base : 0x80000000 Firmware Size : 100 KB Runtime SBI Version : 0.2 Domain0 Name : root Domain0 Boot HART : 0 Domain0 HARTs : 0* Domain0 Region00 : 0x0000000080000000-0x000000008001ffff () Domain0 Region01 : 0x0000000000000000-0xffffffffffffffff (R,W,X) Domain0 Next Address : 0x0000000080200000 Domain0 Next Arg1 : 0x000000008f000000 Domain0 Next Mode : S-mode Domain0 SysReset : yes Boot HART ID : 0 Boot HART Domain : root Boot HART ISA : rv64imafdcsu Boot HART Features : scounteren,mcounteren,time Boot HART PMP Count : 16 Boot HART PMP Granularity : 4 Boot HART PMP Address Bits: 54 Boot HART MHPM Count : 0 Boot HART MHPM Count : 0 Boot HART MIDELEG : 0x0000000000000222 Boot HART MEDELEG : 0x000000000000b109 heap: [0x8028d8a8 - 0x8428d8a8] \ | / - RT - Thread Operating System / | \ 5.2.0 build Nov 14 2024 15:41:57 2006 - 2024 Copyright by RT-Thread team lwIP-2.0.3 initialized! [I/sal.skt] Socket Abstraction Layer initialize success. [I/utest] utest is initialize success. [I/utest] total utest testcase num: (0) file system initialization done! Hello RISC-V msh /> ``` The running results of RT-Thread Smart version are as follows: ```shell $ ./qemu-nographic.sh OpenSBI v0.9 ____ _____ ____ _____ / __ \ / ____| _ \_ _| | | | |_ __ ___ _ __ | (___ | |_) || | | | | | '_ \ / _ \ '_ \ \___ \| _ < | | | |__| | |_) | __/ | | |____) | |_) || |_ \____/| .__/ \___|_| |_|_____/|____/_____| | | |_| Platform Name : riscv-virtio,qemu Platform Features : timer,mfdeleg Platform HART Count : 1 Firmware Base : 0x80000000 Firmware Size : 100 KB Runtime SBI Version : 0.2 Domain0 Name : root Domain0 Boot HART : 0 Domain0 HARTs : 0* Domain0 Region00 : 0x0000000080000000-0x000000008001ffff () Domain0 Region01 : 0x0000000000000000-0xffffffffffffffff (R,W,X) Domain0 Next Address : 0x0000000080200000 Domain0 Next Arg1 : 0x000000008f000000 Domain0 Next Mode : S-mode Domain0 SysReset : yes Boot HART ID : 0 Boot HART Domain : root Boot HART ISA : rv64imafdcsu Boot HART Features : scounteren,mcounteren,time Boot HART PMP Count : 16 Boot HART PMP Granularity : 4 Boot HART PMP Address Bits: 54 Boot HART MHPM Count : 0 Boot HART MHPM Count : 0 Boot HART MIDELEG : 0x0000000000000222 Boot HART MEDELEG : 0x000000000000b109 heap: [0x002ef030 - 0x042ef030] \ | / - RT - Thread Smart Operating System / | \ 5.2.0 build Nov 14 2024 15:48:43 2006 - 2024 Copyright by RT-Thread team lwIP-2.0.3 initialized! [I/sal.skt] Socket Abstraction Layer initialize success. [I/utest] utest is initialize success. [I/utest] total utest testcase num: (0) [I/drivers.serial] Using /dev/ttyS0 as default console file system initialization done! Hello RISC-V msh /> ``` # 4. How to use rv64ilp32 toolchain - Toolchain address: - Usage: - Configure toolchain path - Modify ABI parameter to: `-mabi=ilp32d` - Then perform regular compilation - Use [script](./qemu-rv64ilp32-nographic.sh) to start QEMU (INFO: QEMU binary is also in the toolchain directory) - Compare the firmware size of the same project compiled using the traditional 64-bit toolchain and the new 32-bit toolchain: Traditional 64-bit toolchain firmware size: ```bash Memory region Used Size Region Size %age Used SRAM: 225856 B 16 MB 1.35% riscv64-unknown-elf-objcopy -O binary rtthread.elf rtthread.bin riscv64-unknown-elf-size rtthread.elf text data bss dec hex filename 150907 3664 71268 225839 3722f rtthread.elf ``` New 32-bit toolchain firmware size: ```bash Memory region Used Size Region Size %age Used SRAM: 209376 B 16 MB 1.25% riscv64-unknown-elf-objcopy -O binary rtthread.elf rtthread.bin riscv64-unknown-elf-size rtthread.elf text data bss dec hex filename 138739 1356 69276 209371 331db rtthread.elf ``` # 5. Contact information Maintainer: [bernard][1] [1]: https://github.com/BernardXiong