devc-virtio

Updated: May 06, 2022

Driver for VirtIO console device, which provides data input and output

Syntax:

devc-virtio [generic_options] [ [-l | -L] -m -n num_entries] [location,irq]

Runs on:

QNX Neutrino

Options:

generic_options
The devc-virtio driver supports all generic serial driver options, except for -b and -o. For information about the generic options, see the devc-ser* reference.
-l
Assume version 0.95 (legacy) VirtIO specification compatibility only. By default, compatibility with versions 0.95 and 1.0 is assumed.
-L
Assume version 1.0 (non-legacy) VirtIO specification compatibility only. By default, compatibility with versions 0.95 and 1.0 is assumed.
-m
Disable MSI vector support. By default, this is enabled.
-n num_entries
VirtIO queue size, as the number of entries to allow in the virtqueues. The default is 16. If you specify 0, the virtqueues are made the maximum size allowed by the device implementation.
location
Use the MMIO VirtIO device found at location, which is the starting address of the device's representation in the guest's VM. This option must be immediately followed by the irq option.

If you don't specify the location, a PCI VirtIO device implementation is assumed. The device implementation you indicate here must match the virtual device's configuration in the underlying VM.

irq
Interrupt request (IRQ) number of the MMIO VirtIO device. This option must immediately follow the location option.

Description:

The devc-virtio driver is the interface for the VirtIO device that emulates console devices and hence, supports data input and output.

Examples:

The options given to the driver must reflect its VM configuration. So if you don't specify options for it in your VM configuration:
vdev virtio-console

...
you can launch the driver without any options:
devc-virtio
If you specify the MMIO VirtIO device options for the driver in your VM:
vdev virtio-console
        loc 0x20000000
        intr gic:38

...
you must provide the same location and IRQ when launching the driver:
devc-virtio 0x20000000,38

For information about configuring virtual devices (vdevs) for QNX hypervisors, see the User's Guide for your hypervisor release.