1=head1 NAME 2 3xen-pci-device-reservations - Xen PCI device ID registry 4 5=head1 Description 6 7PCI vendor ID 0x5853 has been reserved for use by Xen systems in order to 8advertise certain virtual hardware to guest virtual machines. The primary 9use of this is with device ID 0x0001 to advertise the Xen Platform PCI 10device - the presence of this virtual device enables a guest Operating 11System (subject to the availability of suitable drivers) to make use of 12paravirtualisation features such as disk and network devices etc. 13 14Some Xen vendors wish to provide alternative and/or additional guest drivers 15that can bind to virtual devices[1]. This may be done using the Xen PCI 16vendor ID of 0x5853 and Xen-vendor/device specific PCI device IDs. This file 17records reservations made within the device ID range in order to avoid 18multiple Xen vendors using conflicting IDs. 19 20=head1 Guidelines 21 22=over 4 23 24=item 1. A vendor may request a range of device IDs by submitting a patch to 25 this file. 26 27=item 2. Vendor allocations should be in the range 0xc000-0xfffe to reduce the 28 possibility of clashes with community IDs assigned from the bottom up. 29 30=item 3. The vendor is responsible for allocations within the range and should 31 try to record specific device IDs in PCI ID databases such as 32 https://pci-ids.ucw.cz and https://devicehunt.com 33 34=back 35 36=head1 Reservations 37 38 range | vendor/product 39 --------------+-------------------------------------------------------------- 40 0x0001 | (Xen Platform PCI device) 41 0x0002 | Citrix XenServer (grandfathered allocation for XenServer 6.1) 42 0xc000-0xc0ff | Citrix XenServer 43 0xc100-0xc1ff | Citrix XenClient 44 0xc200-0xc2ff | XCP-ng Project (https://xcp-ng.org) 45 46=head1 Notes 47 48=over 4 49 50=item 1. 51 52Upstream QEMU provides a parameterized device called xen-pvdevice that 53can be used to host guest drivers. Execute: 54 55 qemu-system-i386 -device xen-pvdevice,help 56 57for a list of all parameters. The following parameters are relevant to 58driver binding: 59 60=over 4 61 62=item vendor-id (default 0x5853) 63 64The PCI vendor ID and subsystem vendor ID of the device. 65 66=item device-id (must be specified) 67 68The PCI device ID and subsystem device ID of the device. 69 70=item revision (default 0x01) 71 72The PCI revision of the device 73 74=back 75 76Also the size parameter (default 0x400000) can be used to specify the 77size of the single MMIO BAR that the device exposes. This area may be 78used by drivers for mapping grant tables, etc. 79 80Note that the presence of the Xen Platform PCI device is generally a 81pre-requisite for an additional xen-pvdevice as it is the platform 82device that provides that IO ports necessary for unplugging emulated 83devices. See hvm-emulated-unplug.markdown for details of the IO ports 84and unplug protocol. 85 86libxl provides support for creation of a single additional xen-pvdevice. 87See the vendor_device parameter in xl.cfg(5). 88 89=back 90