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+# SPDX-License-Identifier: GPL-2.0+
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+#
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+# Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
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+
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+U-Boot on QEMU's 'virt' machine on RISC-V
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+=========================================
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+
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+QEMU for RISC-V supports a special 'virt' machine designed for emulation and
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+virtualization purposes. This document describes how to run U-Boot under it.
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+Both 32-bit 64-bit targets are supported.
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+
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+The QEMU virt machine models a generic RISC-V virtual machine with support for
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+the VirtIO standard networking and block storage devices. It has CLINT, PLIC,
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+16550A UART devices in addition to VirtIO and it also uses device-tree to pass
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+configuration information to guest software. It implements RISC-V privileged
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+architecture spec v1.10.
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+
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+Building U-Boot
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+---------------
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+Set the CROSS_COMPILE environment variable as usual, and run:
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+
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+- For 32-bit RISC-V:
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+ make qemu-riscv32_defconfig
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+ make
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+
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+- For 64-bit RISC-V:
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+ make qemu-riscv64_defconfig
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+ make
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+
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+Running U-Boot
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+--------------
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+The minimal QEMU command line to get U-Boot up and running is:
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+
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+- For 32-bit RISC-V:
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+ qemu-system-riscv32 -nographic -machine virt -kernel u-boot
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+
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+- For 64-bit RISC-V:
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+ qemu-system-riscv64 -nographic -machine virt -kernel u-boot
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+
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+The commands above create targets with 128MiB memory by default.
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+A freely configurable amount of RAM can be created via the '-m'
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+parameter. For example, '-m 2G' creates 2GiB memory for the target,
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+and the memory node in the embedded DTB created by QEMU reflects
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+the new setting.
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+
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+These have been tested in QEMU 3.0.0.
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