From 510e379c49ba8e0d90960d8cbc2ffb91091e229a Mon Sep 17 00:00:00 2001 From: Bin Meng Date: Wed, 26 Sep 2018 06:55:21 -0700 Subject: riscv: Add QEMU virt board support This adds QEMU RISC-V 'virt' board target support, with the hope of helping people easily test U-Boot on RISC-V. The QEMU virt machine models a generic RISC-V virtual machine with support for the VirtIO standard networking and block storage devices. It has CLINT, PLIC, 16550A UART devices in addition to VirtIO and it also uses device-tree to pass configuration information to guest software. It implements RISC-V privileged architecture spec v1.10. Both 32-bit and 64-bit builds are supported. Support is pretty much preliminary, only booting to U-Boot shell with the UART driver on a single core. Booting Linux is not supported yet. Signed-off-by: Bin Meng Reviewed-by: Lukas Auer --- doc/README.qemu-riscv | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 doc/README.qemu-riscv (limited to 'doc') diff --git a/doc/README.qemu-riscv b/doc/README.qemu-riscv new file mode 100644 index 0000000..e2e4804 --- /dev/null +++ b/doc/README.qemu-riscv @@ -0,0 +1,46 @@ +# SPDX-License-Identifier: GPL-2.0+ +# +# Copyright (C) 2018, Bin Meng + +U-Boot on QEMU's 'virt' machine on RISC-V +========================================= + +QEMU for RISC-V supports a special 'virt' machine designed for emulation and +virtualization purposes. This document describes how to run U-Boot under it. +Both 32-bit 64-bit targets are supported. + +The QEMU virt machine models a generic RISC-V virtual machine with support for +the VirtIO standard networking and block storage devices. It has CLINT, PLIC, +16550A UART devices in addition to VirtIO and it also uses device-tree to pass +configuration information to guest software. It implements RISC-V privileged +architecture spec v1.10. + +Building U-Boot +--------------- +Set the CROSS_COMPILE environment variable as usual, and run: + +- For 32-bit RISC-V: + make qemu-riscv32_defconfig + make + +- For 64-bit RISC-V: + make qemu-riscv64_defconfig + make + +Running U-Boot +-------------- +The minimal QEMU command line to get U-Boot up and running is: + +- For 32-bit RISC-V: + qemu-system-riscv32 -nographic -machine virt -kernel u-boot + +- For 64-bit RISC-V: + qemu-system-riscv64 -nographic -machine virt -kernel u-boot + +The commands above create targets with 128MiB memory by default. +A freely configurable amount of RAM can be created via the '-m' +parameter. For example, '-m 2G' creates 2GiB memory for the target, +and the memory node in the embedded DTB created by QEMU reflects +the new setting. + +These have been tested in QEMU 3.0.0. -- cgit v1.1