2.7 Virtio P9 device component

The VirtioP9Device component is included in Base, BaseR, and A-profile VE platforms. It implements a subset of the Plan 9 file protocol over a virtio transport. It enables accessing a directory on the host's filesystem within Linux, or another operating system that implements the protocol, running on a platform model.

Take the following steps to use this component:

  • Use a version of Linux that supports v9fs over virtio and virtio-mmio devices.
  • Update the device tree to include the VirtioP9Device component, or specify it on the kernel command-line, as shown below. The address range for both VE and Base platforms is 0x1C140000-0x1C14FFFF.

    The interrupt number is 43, or IRQ 75, for both VE and Base platforms.

  • Set the following parameter to the directory on the host that you want to mount in the model:

  • On Linux, mount the host directory by using the following command in the model:
    $ mount -t 9p -o trans=virtio,version=9p2000.L FM <mount point>

Example kernel command-line argument:


Example entries for DTS files:

  • Add this entry next to the corresponding virtio_block entry:

    virtio_p9@0140000 { 
           compatible = "virtio,mmio"; 
           reg = <0x140000 0x1000>; 
           interrupts = <0x2b>; 
  • Add this entry to the interrupt map:

    <0 0 43 &gic 0 43 4>;
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