setpci - configure PCI devices
] devices operations
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
for details on access rights.
- Tells setpci to be verbose and display detailed information about
configuration space accesses.
- 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.
- `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.
- Show detailed help on available options. This option should be used
- Show a list of all known PCI registers and capabilities. This option
should be used stand-alone.
PCI access options¶
The PCI utilities use the PCI library to talk to PCI devices (see
for details). You can use the following options to influence
- -A <method>
- 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.
- -O <param>=<value>
- 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.
- Use direct hardware access via Intel configuration mechanism 1. (This is a
shorthand for -A intel-conf1.)
- Use direct hardware access via Intel configuration mechanism 2. (This is a
shorthand for -A intel-conf2.)
- Increase debug level of the library.
Before each sequence of operations you need to select which devices you wish
that operation 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 hexadecimal. 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.
- -d [<vendor>]:[<device>]
- Select devices with specified vendor and device ID. Both ID's are given in
hexadecimal and may be omitted or given as "*", both meaning
are combined, only devices that match both criteria
are selected. When multiple 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
... where each value
is either a
hexadecimal number or an expression of type data
are hexadecimal numbers. In the latter case, only
the bits corresponding to binary ones in the mask
(technically, this is a read-modify-write operation).
There are several ways how to identity a register:
- Tell its address in hexadecimal.
- Spell its name. Setpci knows the names of all registers in the standard
configuration headers. Use ` setpci --dumpregs' to get the complete
list. See PCI bus specifications for the precise meaning of these
registers or consult header.h or /usr/include/pci/pci.h for
a brief sketch.
- 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.
- If the name of the capability is not known to setpci, you can refer
to it by its number in the form CAP id or ECAPid, where
id is the numeric identifier of the capability in hexadecimal.
- 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 living within a capability, or to modify parts of
- 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 referring to a register by its name and
the width of the register is well known.
All names of registers and width specifiers are case-insensitive.
- asks for the word-sized command register.
- 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
- 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 <email@example.com>.