1 .. SPDX-License-Identifier: GPL-2.0+
2 .. Copyright (C) 2017, Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
7 QEMU for ARM supports a special 'virt' machine designed for emulation and
8 virtualization purposes. This document describes how to run U-Boot under it.
9 Both 32-bit ARM and AArch64 are supported.
11 The 'virt' platform provides the following as the basic functionality:
13 - A freely configurable amount of CPU cores
14 - U-Boot loaded and executing in the emulated flash at address 0x0
15 - A generated device tree blob placed at the start of RAM
16 - A freely configurable amount of RAM, described by the DTB
17 - A PL011 serial port, discoverable via the DTB
18 - An ARMv7/ARMv8 architected timer
19 - PSCI for rebooting the system
20 - A generic ECAM-based PCI host controller, discoverable via the DTB
22 Additionally, a number of optional peripherals can be added to the PCI bus.
26 Set the CROSS_COMPILE environment variable as usual, and run:
30 make qemu_arm_defconfig
35 make qemu_arm64_defconfig
40 The minimal QEMU command line to get U-Boot up and running is:
44 qemu-system-arm -machine virt -bios u-boot.bin
48 qemu-system-aarch64 -machine virt -cpu cortex-a57 -bios u-boot.bin
50 Note that for some odd reason qemu-system-aarch64 needs to be explicitly
51 told to use a 64-bit CPU or it will boot in 32-bit mode.
53 Additional persistent U-boot environment support can be added as follows:
55 - Create envstore.img using qemu-img::
57 qemu-img create -f raw envstore.img 64M
59 - Add a pflash drive parameter to the command line::
61 -drive if=pflash,format=raw,index=1,file=envstore.img
63 Additional peripherals that have been tested to work in both U-Boot and Linux
64 can be enabled with the following command line parameters:
66 - To add a Serial ATA disk via an Intel ICH9 AHCI controller, pass e.g.::
68 -drive if=none,file=disk.img,id=mydisk -device ich9-ahci,id=ahci -device ide-drive,drive=mydisk,bus=ahci.0
70 - To add an Intel E1000 network adapter, pass e.g.::
72 -netdev user,id=net0 -device e1000,netdev=net0
74 - To add an EHCI-compliant USB host controller, pass e.g.::
76 -device usb-ehci,id=ehci
78 - To add a NVMe disk, pass e.g.::
80 -drive if=none,file=disk.img,id=mydisk -device nvme,drive=mydisk,serial=foo
82 These have been tested in QEMU 2.9.0 but should work in at least 2.5.0 as well.