pciconf(8)

NAME

pciconf - diagnostic utility for the PCI bus

SYNOPSIS

pciconf -l [-v]
pciconf -a selector
pciconf -r [-b | -h] selector addr[:addr2]
pciconf -w [-b | -h] selector addr value

DESCRIPTION

The pciconf utility provides a command line interface to

functionality
provided by the pci(4) ioctl(2) interface. As such, some of

the functions are only available to users with write access to

/dev/pci, normally
only the super-user.

With the -l option, it lists all devices found by the boot

probe in the
following format:

foo0@pci0:4:0: class=0x010000 card=0x00000000

chip=0x000f1000 rev=0x01 hdr=0x00
bar0@pci0:5:0: class=0x000100 card=0x00000000

chip=0x88c15333 rev=0x00 hdr=0x00
none0@pci0:6:0: class=0x020000 card=0x00000000

chip=0x802910ec rev=0x00 hdr=0x00

If the -v option is supplied, pciconf will attempt to load

the vendor/device information database, and print vendor, device,

class and subclass identification strings for each device.

The first column gives the device name, unit number, and

selector. If
there is no device configured in the kernel for the PCI de

vice in question, the device name will be ``none''. Unit numbers for

unconfigured
devices start at zero and are incremented for each unconfig

ured device
that is encountered. The selector is in a form which may

directly be
used for the other forms of the command. The second column

is the class
code, with the class byte printed as two hex digits, fol

lowed by the subclass and the interface bytes. The third column gives the

contents of
the subvendorid register, introduced in revision 2.1 of the

PCI standard.
It is 0 for most current (2.0) PCI cards, but is supposed to

be loaded
with a unique card identification code in newly developed

PCI cards. The
field consists of the card ID in the upper half and the card

vendor ID in
the lower half of the value.

The fourth column contains the chip device ID, which identi

fies the chip
this card is based on. It consists of two fields, identify

ing the chip
and its vendor, as above. The fifth column prints the

chip's revision.
The sixth column describes the header type. Currently as

signed header
types are 0 for all devices except PCI to PCI bridges, and 1

for such
bridge chips. If the most significant bit of the header

type register is
set for function 0 of a PCI device, it is a multi-function

device, which
contains several (similar or independent) functions on one

chip.

All invocations of pciconf except for -l require a selector

of the form
pcibus:device (optionally followed by :function). A final

colon may be
appended and will be ignored; this is so that the first col

umn in the
output of pciconf -l can be used without modification. All

numbers are
base 10.

With the -a flag, pciconf determines whether any driver has

been assigned
to the device identified by selector. An exit status of ze

ro indicates
that the device has a driver; non-zero indicates that it

does not.

The -r option reads a configuration space register at byte

offset addr of
device selector and prints out its value in hexadecimal.

The optional
second address addr2 specifies a range to read. The -w op

tion writes the
value into a configuration space register at byte offset

addr of device
selector. For both operations, the flags -b and -h select

the width of
the operation; -b indicates a byte operation, and -h indi

cates a halfword
(two-byte) operation. The default is to read or write a

longword (four
bytes).

ENVIRONMENT

The PCI vendor/device information database is normally read

from
/usr/share/misc/pci_vendors. This path can be overridden by

setting the
environment variable PCICONF_VENDOR_DATABASE.

SEE ALSO

ioctl(2), kldload(8)

HISTORY

The pciconf utility appeared first in FreeBSD 2.2. The -a

option was
added for PCI KLD support in FreeBSD 3.0.

AUTHORS

The pciconf utility was written by Stefan Esser and Garrett

Wollman.

BUGS

The -b and -h options are implemented in pciconf, but not in

the underlying ioctl(2).

It might be useful to give non-root users access to the -a

and -r
options. But only root will be able to execute a kldload to

provide the
device with a driver KLD, and reading of configuration space

registers
may cause a failure in badly designed PCI chips.

BSD February 7, 1997

BSD