setpci(8) The PCI Utilities setpci(8)
setpci - configure PCI devices
setpci [options] devices operations...
setpci is a utility for querying and configuring PCI devices.
All numbers are entered in hexadecimal notation.
Root privileges are necessary for almost all operations, excluding reads of the standard
header of the configuration space on some operating systems. Please see lspci(8) for
details on access rights.
-v Tells setpci to be verbose and display detailed information about configuration
-f Tells setpci not to complain when there's nothing to do (when no devices are
selected). This option is intended for use in widely-distributed configuration
scripts where it's uncertain whether the device in question is present in the
machine or not.
-D `Demo mode' -- don't write anything to the configuration registers. It's useful to
try setpci -vD to verify that your complex sequence of setpci operations does what
you think it should do.
Show setpci version. This option should be used stand-alone.
--help Show detailed help on available options. This option should be used stand-alone.
Show a list of all known PCI registers and capabilities. This option should be used
PCI access options
The PCI utilities use the PCI library to talk to PCI devices (see pcilib(7) for details).
You can use the following options to influence its behavior:
The library supports a variety of methods to access the PCI hardware. By default,
it uses the first access method available, but you can use this option to override
this decision. See -A help for a list of available methods and their descriptions.
The behavior of the library is controlled by several named parameters. This option
allows to set the value of any of the parameters. Use -O help for a list of known
parameters and their default values.
-H1 Use direct hardware access via Intel configuration mechanism 1. (This is a short-
hand for -A intel-conf1.)
-H2 Use direct hardware access via Intel configuration mechanism 2. (This is a short-
hand for -A intel-conf2.)
-G Increase debug level of the library.
Before each sequence of operations you need to select which devices you wish that opera-
tion to affect.
Consider only devices in the specified domain (in case your machine has several
host bridges, they can either share a common bus number space or each of them can
address a PCI domain of its own; domains are numbered from 0 to ffff), bus (0 to
ff), slot (0 to 1f) and function (0 to 7). Each component of the device address
can be omitted or set to "*", both meaning "any value". All numbers are hexadeci-
mal. E.g., "0:" means all devices on bus 0, "0" means all functions of device 0 on
any bus, "0.3" selects third function of device 0 on all buses and ".4" matches
only the fourth function of each device.
Select devices with specified vendor and device ID. Both ID's are given in hexadec-
imal and may be omitted or given as "*", both meaning "any value".
When -s and -d are combined, only devices that match both criteria are selected. When mul-
tiple options of the same kind are specified, the rightmost one overrides the others.
There are two kinds of operations: reads and writes. To read a register, just specify its
name. Writes have the form name=value,value... where each value is either a hexadecimal
number or an expression of type data:mask where both data and mask are hexadecimal num-
bers. In the latter case, only the bits corresponding to binary ones in the mask are
changed (technically, this is a read-modify-write operation).
There are several ways how to identity a register:
o Tell its address in hexadecimal.
o Spell its name. Setpci knows the names of all registers in the standard configura-
tion headers. Use `setpci --dumpregs' to get the complete list. See PCI bus speci-
fications for the precise meaning of these registers or consult header.h or
/usr/include/pci/pci.h for a brief sketch.
o If the register is a part of a PCI capability, you can specify the name of the
capability to get the address of its first register. See the names starting with
`CAP_' or `ECAP_' in the --dumpregs output.
o If the name of the capability is not known to setpci, you can refer to it by its
number in the form CAPid or ECAPid, where id is the numeric identifier of the capa-
bility in hexadecimal.
o Each of the previous formats can be followed by +offset to add an offset (a hex
number) to the address. This feature can be useful for addressing of registers liv-
ing within a capability, or to modify parts of standard registers. IP o Finally,
you should append a width specifier .B, .W, or .L to choose how many bytes (1, 2,
or 4) should be transferred. The width can be omitted if you are accessing a named
register whose width is well known.
All names of registers and width specifiers are case-insensitive.
asks for the word-sized command register.
4.w is a numeric address of the same register.
asks for a 32-bit word starting at the location of the command register, i.e., the
command and status registers together.
specifies the upper byte of the vendor ID register (remember, PCI is little-
corresponds to the second word of the power management capability.
asks for the first 32-bit word of the extended capability with ID 0x108.
The PCI Utilities are maintained by Martin Mares <firstname.lastname@example.org>.
pciutils-3.1.7 31 January 2010 setpci(8)