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. Warning:
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 plat-
forms. Requires root privileges. Warning: This method needs to be
properly configured via the mmio-conf1-ext.addrs parameter.
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 compatible
systems is ECAM mapping read from the MCFG table specified by the
ecam.acpimcfg parameter. On EFI compatible systems, ACPI MCFG ta-
ble can be located in physical memory via EFI system table speci-
fied 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 disabled. 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 mappings can be
specified by the ecam.addrs parameter which takes precedence over
ACPI MCFG table. This option is required on systems 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 Configuration
Manager via cfgmgr32.dll system library. This method does not re-
quire any special Administrator rights or privileges. Configura-
tion Manager provides only basic information about devices, as-
signed 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 provides read-
only virtual emulation based on information from Configuration
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 library 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 lo-
cal Administrators have by default. Not available on 64-bit sys-
tems 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 driver
has some restrictions. Process needs to have Debug privilege and
Windows system has to be booted with Debugging option. Debugging
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
aos-expansion
Access method used on PowerPC Amiga running OS4+. Access is made
through Expansion.library. It offers read and write access to
configuration space.
PARAMETERS
The library is controlled by several parameters. They should have sensi-
ble 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 differ-
ent 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 emu-
lated 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. An initial ~/
is expanded to the user's home directory.
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-3.13.0 30 May 2024 pcilib(7)
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