pcilib(7) The PCI Utilities pcilib(7)
NAME
pcilib - a library for accessing PCI devices
DESCRIPTION
The PCI library (also known as pcilib and libpci) is a portable library
for accessing PCI devices and their configuration space.
ACCESS METHODS
The library supports a variety of methods to access the configuration
space on different operating systems. By default, the first matching
method in this list is used, but you can specify override the decision
(see the -A switch of lspci).
linux-sysfs
The /sys filesystem on Linux 2.6 and newer. The standard header
of the config space is available to all users, the rest only to
root. Supports extended configuration space, PCI domains, VPD
(from Linux 2.6.26), physical slots (also since Linux 2.6.26)
and information on attached kernel drivers.
linux-proc
The /proc/bus/pci interface supported by Linux 2.1 and newer.
The standard header of the config space is available to all
users, the rest only to root.
intel-conf1
Direct hardware access via Intel configuration mechanism 1.
Available on i386 and compatibles on Linux, Solaris/x86, GNU
Hurd, Windows, BeOS and Haiku. Requires root privileges.
intel-conf2
Direct hardware access via Intel configuration mechanism 2.
Available on i386 and compatibles on Linux, Solaris/x86, GNU
Hurd, Windows, BeOS and Haiku. Requires root privileges. Warn-
ing: This method is able to address only the first 16 devices on
any bus and it seems to be very unreliable in many cases.
mmio-conf1
Direct hardware access via Intel configuration mechanism 1 via
memory-mapped I/O. Mostly used on non-i386 platforms. Requires
root privileges. Warning: This method needs to be properly con-
figured via the mmio-conf1.addrs parameter.
mmio-conf1-ext
Direct hardware access via Extended PCIe Intel configuration
mechanism 1 via memory-mapped I/O. Mostly used on non-i386
platforms. Requires root privileges. Warning: This method needs
to be properly configured via the mmio-conf1-ext.addrs parame-
ter.
ecam Direct hardware access via PCIe ECAM (Enhanced Configuration Ac-
cess Mechanism). Available on all PCIe-compliant hardware. Re-
quires root privileges and access to physical memory (on Linux
systems disabled CONFIG_STRICT_DEVMEM option). On ACPI compati-
ble systems is ECAM mapping read from the MCFG table specified
by the ecam.acpimcfg parameter. On EFI compatible systems, ACPI
MCFG table can be located in physical memory via EFI system ta-
ble specified by the ecam.efisystab parameter. On FreeBSD/NetBSD
systems, physical address of ACPI MCFG table can be located by
kenv or sysctl interface when the ecam.bsd parameter is not dis-
abled. On x86 BIOS compatible systems, ACPI MCFG table can be
located in physical memory by scanning x86 BIOS memory when the
ecam.x86bios parameter is not disabled. Alternatively ECAM map-
pings can be specified by the ecam.addrs parameter which takes
precedence over ACPI MCFG table. This option is required on sys-
tems without ACPI and also on systems without EFI or x86 BIOS.
fbsd-device
The /dev/pci device on FreeBSD. Requires root privileges.
aix-device
Access method used on AIX. Requires root privileges.
nbsd-libpci
The /dev/pci0 device on NetBSD accessed using the local libpci
library.
obsd-device
The /dev/pci device on OpenBSD. Requires root privileges.
dump Read the contents of configuration registers from a file speci-
fied in the dump.name parameter. The format corresponds to the
output of lspci -x.
darwin Access method used on Mac OS X / Darwin. Must be run as root and
the system must have been booted with debug=0x144.
win32-cfgmgr32
Device listing on Windows systems using the Windows Configura-
tion Manager via cfgmgr32.dll system library. This method does
not require any special Administrator rights or privileges. Con-
figuration Manager provides only basic information about de-
vices, assigned resources and device tree structure. There is no
access to the PCI configuration space but libpci either tries to
use other access method to access configuration space or it pro-
vides read-only virtual emulation based on information from Con-
figuration Manager. Other access method can be chosen by the
win32.cfgmethod parameter. By default the first working one is
selected (if any). Starting with Windows 8 (NT 6.2) it is not
possible to retrieve resources from 32-bit application or li-
brary on 64-bit system.
win32-sysdbg
Access to the PCI configuration space via NT SysDbg interface on
Windows systems. Process needs to have Debug privilege, which
local Administrators have by default. Not available on 64-bit
systems and neither on recent 32-bit systems. Only devices from
the first domain are accessible and only first 256 bytes of the
PCI configuration space is accessible via this method.
win32-kldbg
Access to the PCI configuration space via Kernel Local Debugging
Driver kldbgdrv.sys. This driver is not part of the Windows sys-
tem but is part of the Microsoft WinDbg tool. It is required to
have kldbgdrv.sys driver installed in the system32 directory or
to have windbg.exe or kd.exe binary in PATH. kldbgdrv.sys dri-
ver has some restrictions. Process needs to have Debug privilege
and Windows system has to be booted with Debugging option. De-
bugging option can be enabled by calling (takes effect after
next boot): bcdedit /debug on
Download links for WinDbg 6.12.2.633 standalone installer from
Microsoft Windows SDK for Windows 7 and .NET Framework 4:
amd64: https://download.microsoft.com/download/A/6/A/A6AC035D-
DA3F-4F0C-ADA4-37C8E5D34E3D/setup/WinSDKDebugging-
Tools_amd64/dbg_amd64.msi
ia64: https://download.microsoft.com/download/A/6/A/A6AC035D-
DA3F-4F0C-ADA4-37C8E5D34E3D/setup/WinSDKDebugging-
Tools_ia64/dbg_ia64.msi
x86: https://download.microsoft.com/download/A/6/A/A6AC035D-
DA3F-4F0C-ADA4-37C8E5D34E3D/setup/WinSDKDebugging-
Tools/dbg_x86.msi
Archived download links of previous WinDbg versions:
https://web.archive.org/web/20110221133326/https://www.mi-
crosoft.com/whdc/devtools/debugging/installx86.mspx
https://web.archive.org/web/20110214012715/https://www.mi-
crosoft.com/whdc/devtools/debugging/install64bit.mspx
PARAMETERS
The library is controlled by several parameters. They should have sen-
sible default values, but in case you want to do something unusual (or
even something weird), you can override them (see the -O switch of
lspci).
Parameters of specific access methods
dump.name
Name of the bus dump file to read from.
fbsd.path
Path to the FreeBSD PCI device.
nbsd.path
Path to the NetBSD PCI device.
obsd.path
Path to the OpenBSD PCI device.
proc.path
Path to the procfs bus tree.
sysfs.path
Path to the sysfs device tree.
devmem.path
Path to the /dev/mem device.
mmio-conf1.addrs
Physical addresses of memory-mapped I/O ports for Intel configu-
ration mechanism 1. CF8 (address) and CFC (data) I/O port ad-
dresses are separated by slash and multiple addresses for dif-
ferent PCI domains are separated by commas. Format:
0xaddr1/0xdata1,0xaddr2/0xdata2,...
mmio-conf1-ext.addrs
Physical addresses of memory-mapped I/O ports for Extended PCIe
Intel configuration mechanism 1. It has same format as mmio-
conf1.addrs parameter.
ecam.addrs
Physical addresses of PCIe ECAM mappings. Each mapping must con-
tains first PCI bus number and physical address where mapping
starts. And then it may contain the length of the mapping, the
last PCI bus number and PCI domain number. When the last PCI bus
number is not provided then it is calculated from the length of
the mapping or it is assumed 0xff. When length of the mapping is
provided then it is calculated from the last PCI bus number. And
when PCI domain is not provided then 0x0 is assumed. All numbers
must be supplied in hexadecimal form (leading prefix 0x is not
required). Multiple mappings are separated by commas. Format:
[domain:]start_bus[-end_bus]:start_addr[+length],...
ecam.acpimcfg
Path to the ACPI MCFG table. Processed by the glob(3) function,
so it may contain wildcards (*).
ecam.efisystab
Path to the EFI system table.
ecam.bsd
When not set to 0 then use BSD kenv or sysctl to find ACPI MCFG
table. Default value is 1 on BSD systems.
ecam.x86bios
When not set to 0 then scan x86 BIOS memory for ACPI MCFG table.
Default value is 1 on x86 systems.
win32.cfgmethod
Config space access method to use with win32-cfgmgr32 on Windows
systems. Value auto or an empty string selects the first access
method which supports access to the config space on Windows.
Value win32-cfgmgr32 or none only builds a read-only virtual em-
ulated config space with information from the Configuration Man-
ager.
Parameters for resolving of ID's via DNS
net.domain
DNS domain containing the ID database.
net.cache_name
Name of the file used for caching of resolved ID's.
Parameters for resolving of ID's via UDEV's HWDB
hwdb.disable
Disable use of HWDB if set to a non-zero value.
SEE ALSO
lspci(8), setpci(8), pci.ids(5), update-pciids(8)
AUTHOR
The PCI Utilities are maintained by Martin Mares <mj@ucw.cz>.
pciutils-3.10.0 01 May 2023 pcilib(7)
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