On Tue, Dec 22, 2015 at 11:50:41AM +0800, Peter Xu wrote: > Hi, > > I got a question related to how virtio pmd driver work without > UIO layer. > > I see that in virtio PMD driver, DPDK will first try to init the > device using UIO interfaces. If it fails, it will try to init by > manipulating IO ports directly (see virtio_resource_init()). > > For the ioport case, is it okay to do it like this? E.g., in > eth_virtio_dev_init(), we are resetting the virtio device, however, > this device should still be owned by virtio-pci driver in the > kernel. > > How is that working? Did I miss anything?
That's for configuration part: as far as we can read/write the right PCI port, virtio pmd configuration will work. Note that on this case, uio just provides another way to tell you where the port is. --yliu