| Tuomas Tynkkynen | d5587fa | 2017-10-09 19:42:41 +0300 | [diff] [blame^] | 1 | # |
| 2 | # Copyright (C) 2017, Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi> |
| 3 | # |
| 4 | # SPDX-License-Identifier: GPL-2.0+ |
| 5 | # |
| 6 | |
| 7 | U-Boot on QEMU's 'virt' machine on ARM |
| 8 | ====================================== |
| 9 | |
| 10 | QEMU for ARM supports a special 'virt' machine designed for emulation and |
| 11 | virtualization purposes. This document describes how to run U-Boot under it. |
| 12 | |
| 13 | The 'virt' platform provides the following as the basic functionality: |
| 14 | |
| 15 | - A freely configurable amount of CPU cores |
| 16 | - U-Boot loaded and executing in the emulated flash at address 0x0 |
| 17 | - A generated device tree blob placed at the start of RAM |
| 18 | - A freely configurable amount of RAM, described by the DTB |
| 19 | - A PL011 serial port, discoverable via the DTB |
| 20 | - An ARMv7 architected timer |
| 21 | - PSCI for rebooting the system |
| 22 | - A generic ECAM-based PCI host controller, discoverable via the DTB |
| 23 | |
| 24 | Additionally, a number of optional peripherals can be added to the PCI bus. |
| 25 | |
| 26 | Building U-Boot |
| 27 | --------------- |
| 28 | Set the CROSS_COMPILE and ARCH=arm environment variables as usual, and run: |
| 29 | |
| 30 | make qemu_arm_defconfig |
| 31 | make |
| 32 | |
| 33 | Running U-Boot |
| 34 | -------------- |
| 35 | The minimal QEMU command line to get U-Boot up and running is: |
| 36 | |
| 37 | qemu-system-arm -machine virt,highmem=off -bios u-boot.bin |
| 38 | |
| 39 | The 'highmem=off' parameter to the 'virt' machine is required for PCI to work |
| 40 | in U-Boot. |
| 41 | |
| 42 | Additional peripherals that have been tested to work in both U-Boot and Linux |
| 43 | can be enabled with the following command line parameters: |
| 44 | |
| 45 | - To add a Serial ATA disk via an Intel ICH9 AHCI controller, pass e.g.: |
| 46 | -drive if=none,file=disk.img,id=mydisk -device ich9-ahci,id=ahci -device ide-drive,drive=mydisk,bus=ahci.0 |
| 47 | - To add an Intel E1000 network adapter, pass e.g.: |
| 48 | -netdev user,id=net0 -device e1000,netdev=net0 |
| 49 | - To add an EHCI-compliant USB host controller, pass e.g.: |
| 50 | -device usb-ehci,id=ehci |
| 51 | - To add a NVMe disk, pass e.g.: |
| 52 | -drive if=none,file=disk.img,id=mydisk -device nvme,drive=mydisk,serial=foo |
| 53 | |
| 54 | These have been tested in QEMU 2.9.0 but should work in at least 2.5.0 as well. |