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xen-pci-device-reservations(7)	      Xen	xen-pci-device-reservations(7)

NAME
       xen-pci-device-reservations - Xen PCI device ID registry

Description
       PCI vendor ID 0x5853 has	been reserved for use by Xen systems in	order
       to advertise certain virtual hardware to	guest virtual machines.	The
       primary use of this is with device ID 0x0001 to advertise the Xen
       Platform	PCI device - the presence of this virtual device enables a
       guest Operating System (subject to the availability of suitable
       drivers)	to make	use of paravirtualisation features such	as disk	and
       network devices etc.

       Some Xen	vendors	wish to	provide	alternative and/or additional guest
       drivers that can	bind to	virtual	devices[1]. This may be	done using the
       Xen PCI vendor ID of 0x5853 and Xen-vendor/device specific PCI device
       IDs. This file records reservations made	within the device ID range in
       order to	avoid multiple Xen vendors using conflicting IDs.

Guidelines
       1. A vendor may request a range of device IDs by	submitting a patch to
       this file.
       2. Vendor allocations should be in the range 0xc000-0xfffe to reduce
       the possibility of clashes with community IDs assigned from the bottom
       up.
       3. The vendor is	responsible for	allocations within the range and
       should try to record specific device IDs	in PCI ID databases such as
       https://pci-ids.ucw.cz and https://devicehunt.com

Reservations
	       range	 | vendor/product
	   --------------+--------------------------------------------------------------
	   0x0001	 | (Xen	Platform PCI device)
	   0x0002	 | Citrix XenServer (grandfathered allocation for XenServer 6.1)
	   0xc000-0xc0ff | Citrix XenServer
	   0xc100-0xc1ff | Citrix XenClient
	   0xc200-0xc2ff | XCP-ng Project (https://xcp-ng.org)

Notes
       1.  Upstream  QEMU  provides a parameterized device called xen-pvdevice
	   that	can be used to host guest drivers. Execute:

	       qemu-system-i386	-device	xen-pvdevice,help

	   for a list of all parameters. The following parameters are relevant
	   to driver binding:

	   vendor-id (default 0x5853)
	       The PCI vendor ID and subsystem vendor ID of the	device.

	   device-id (must be specified)
	       The PCI device ID and subsystem device ID of the	device.

	   revision (default 0x01)
	       The PCI revision	of the device

	   Also	the size parameter (default 0x400000) can be used  to  specify
	   the	size of	the single MMIO	BAR that the device exposes. This area
	   may be used by drivers for mapping grant tables, etc.

	   Note	that the presence of the Xen Platform PCI device is  generally
	   a  pre-requisite  for  an  additional  xen-pvdevice	as  it	is the
	   platform  device  that  provides  that  IO  ports   necessary   for
	   unplugging  emulated	 devices. See hvm-emulated-unplug.markdown for
	   details of the IO ports and unplug protocol.

	   libxl provides support for creation of  a  single  additional  xen-
	   pvdevice.  See the vendor_device parameter in xl.cfg(5).

4.19.2-pre			  2025-02-17	xen-pci-device-reservations(7)

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