1xen-pci-device-reservations(7) Xen xen-pci-device-reservations(7)
2
6 PCI vendor ID 0x5853 has been reserved for use by Xen systems in order
7 to advertise certain virtual hardware to guest virtual machines. The
8 primary use of this is with device ID 0x0001 to advertise the Xen
9 Platform PCI device - the presence of this virtual device enables a
10 guest Operating System (subject to the availability of suitable
11 drivers) to make use of paravirtualisation features such as disk and
12 network devices etc.
13 Some Xen vendors wish to provide alternative and/or additional guest
15 drivers that can bind to virtual devices[1]. This may be done using the
16 Xen PCI vendor ID of 0x5853 and Xen-vendor/device specific PCI device
17 IDs. This file records reservations made within the device ID range in
18 order to avoid multiple Xen vendors using conflicting IDs.
19
21 1. A vendor may request a range of device IDs by submitting a patch to
22 this file.
23 2. Vendor allocations should be in the range 0xc000-0xfffe to reduce
24 the possibility of clashes with community IDs assigned from the bottom
25 up.
26 3. The vendor is responsible for allocations within the range and
27 should try to record specific device IDs in PCI ID databases such as
28 http://pciids.sourceforge.net and http//www.pcidatabase.com
29
31 range | vendor/product
32 --------------+--------------------------------------------------------------
33 0x0001 | (Xen Platform PCI device)
34 0x0002 | Citrix XenServer (grandfathered allocation for XenServer 6.1)
35 0xc000-0xc0ff | Citrix XenServer
36 0xc100-0xc1ff | Citrix XenClient
37
39 1. Upstream QEMU provides a parameterized device called xen-pvdevice
40 that can be used to host guest drivers. Execute:
41 qemu-system-i386 -device xen-pvdevice,help
43 for a list of all parameters. The following parameters are relevant
45 to driver binding:
46 vendor-id (default 0x5853)
48 The PCI vendor ID and subsystem vendor ID of the device.
49 device-id (must be specified)
51 The PCI device ID and subsystem device ID of the device.
52 revision (default 0x01)
54 The PCI revision of the device
55 Also the size parameter (default 0x400000) can be used to specify
57 the size of the single MMIO BAR that the device exposes. This area
58 may be used by drivers for mapping grant tables, etc.
59 Note that the presence of the Xen Platform PCI device is generally
61 a pre-requisite for an additional xen-pvdevice as it is the
62 platform device that provides that IO ports necessary for
63 unplugging emulated devices. See hvm-emulated-unplug.markdown for
64 details of the IO ports and unplug protocol.
65 libxl provides support for creation of a single additional xen-
67 pvdevice. See the vendor_device parameter in xl.cfg(5).
684.11.1 2018-11-29 xen-pci-device-reservations(7)