[Qemu-devel] Adds virtio_net as the default netcard for mips boston board

[Tommy Jin]

Hi,

This is a patch for Mips Boston board.
Boston didn't bring up any netcard by default, this is not so convenient for 
users who are verifying network related functionalities on this board.
As the linux kernel has already supported virtio_net, now add a virtio netcard 
for boston, to make virtio work properly, please:
1. set virtio net options in linux kernel, saying CONFIG_VIRTIO && 
CONFIG_VIRTIO_PCI && CONFIG_VIRTIO_NET
2. specify model=virtio when you start boston in qemu.

Best regards,
Tommy