setpci

setpci(8)                      The PCI Utilities                     setpci(8)

NAME
       setpci - configure PCI devices

SYNOPSIS
       setpci [options] devices operations...

DESCRIPTION
       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 operat-
       ing systems.  Please see lspci(8) for details on access rights.

OPTIONS
   General options
       -v     Tells  setpci  to  be  verbose  and display detailed information
              about configuration space accesses.

       -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 regis-
              ters.  It's useful to try setpci -vD to verify that your complex
              sequence of setpci operations does what you think it should do.

       --version
              Show setpci version. This option should be used stand-alone.

       --help Show  detailed  help on available options. This option should be
              used stand-alone.

       --dumpregs
              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
       pcilib(7) for details). You can use the following options to  influence
       its behavior:

       -A <method>
              The  library  supports  a  variety  of methods to access the PCI
              hardware.  By default, it uses the first  access  method  avail-
              able, 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  pa-
              rameters.  This option allows one 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 shorthand for -A intel-conf1.)

       -H2    Use direct hardware access via Intel configuration mechanism  2.
              (This is a shorthand for -A intel-conf2.)

       -G     Increase debug level of the library.

DEVICE SELECTION
       Before each sequence of operations you need to select which devices you
       wish that operation to affect.

       -s [[[[<domain>]:]<bus>]:][<slot>][.[<func>]]
              Consider only devices in the specified domain (in case your  ma-
              chine  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" se-
              lects 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 "any value".

       When  -s and -d 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.

OPERATIONS
       There  are  two kinds of operations: reads and writes. To read a regis-
       ter, 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 numbers. 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  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/in-
              clude/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 reg-
              ister. 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 capability 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 living within a capability,
              or to modify parts of standard registers.

       o      To choose how many bytes (1, 2, or 4) should be transferred, you
              should  append a width specifier .B, .W, or .L. The width can be
              omitted if you are referring to a register by its name  and  the
              width of the register is well known.

       o      Finally,  if  a  capability exists multiple times you can choose
              which one to target using @number. Indexing starts at 0.

       All names of registers and width specifiers are case-insensitive.

EXAMPLES
       COMMAND
              asks for the word-sized command register.

       4.w    is a numeric address of the same register.

       COMMAND.l
              asks for a 32-bit word starting at the location of  the  command
              register, i.e., the command and status registers together.

       VENDOR_ID+1.b
              specifies  the  upper  byte of the vendor ID register (remember,
              PCI is little-endian).

       CAP_PM+2.w
              corresponds to the second word of the power management  capabil-
              ity.

       ECAP108.l
              asks  for  the first 32-bit word of the extended capability with
              ID 0x108.

SEE ALSO
       lspci(8), pcilib(7)

AUTHOR
       The PCI Utilities are maintained by Martin Mares <mj@ucw.cz>.

pciutils-3.6.4                  25 January 2020                      setpci(8)