1 'virt' generic virtual platform
2 ===============================
4 The ``virt`` board is a platform which does not correspond to any
5 real hardware; it is designed for use in virtual machines.
6 It is the recommended board type if you simply want to run
7 a guest such as Linux and do not care about reproducing the
8 idiosyncrasies and limitations of a particular bit of real-world
15 * 8 virtio-mmio transport devices
18 * SiFive Test device for poweroff and reboot
19 * SMP (OpenRISC multicore using ompic)
24 The virt machine can be started using the ``-kernel`` and ``-initrd`` options
25 to load a Linux kernel and optional disk image. For example:
29 $ qemu-system-or1k -cpu or1220 -M or1k-sim -nographic \
30 -device virtio-net-device,netdev=user -netdev user,id=user,net=10.9.0.1/24,host=10.9.0.100 \
31 -device virtio-blk-device,drive=d0 -drive file=virt.qcow2,id=d0,if=none,format=qcow2 \
33 -initrd initramfs.cpio.gz \
36 Linux guest kernel configuration
37 """"""""""""""""""""""""""""""""
39 The 'virt_defconfig' for Linux openrisc kernels includes the right drivers for
42 Hardware configuration information
43 """"""""""""""""""""""""""""""""""
45 The ``virt`` board automatically generates a device tree blob ("dtb") which it
46 passes to the guest. This provides information about the addresses, interrupt
47 lines and other configuration of the various devices in the system.
49 The location of the DTB will be passed in register ``r3`` to the guest operating