NAME
pciconf
—
diagnostic utility for the PCI
bus
SYNOPSIS
pciconf |
-l [-bcv ] |
pciconf |
-a selector |
pciconf |
-r [-b |
-h ] selector
addr[:addr2] |
pciconf |
-w [-b |
-h ] selector addr value |
DESCRIPTION
Thepciconf
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@pci0:0:4:0: class=0x010000 card=0x00000000 chip=0x000f1000 rev=0x01 hdr=0x00 bar0@pci0:0:5:0: class=0x000100 card=0x00000000 chip=0x88c15333 rev=0x00 hdr=0x00 none0@pci0:0:6:0: class=0x020000 card=0x00000000 chip=0x802910ec rev=0x00 hdr=0x00
The first column gives the device name, unit number, and selector. If there is no device configured in the kernel for the PCI device in question, the device name will be “none”. Unit numbers for unconfigured devices start at zero and are incremented for each unconfigured 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, followed by the sub-class and the interface bytes. The third column gives the contents of the subvendorid register, introduced in revision 2.1 of the PCI standard. Note that it will be 0 for older 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 identifies the chip this card is based on. It consists of two fields, identifying the chip and its vendor, as above. The fifth column prints the chip's revision. The sixth column describes the header type. Currently assigned header types include 0 for most devices, 1 for PCI to PCI bridges, and 2 for PCI to CardBus bridges. 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.
If the -b
option is supplied,
pciconf
will list any base address registers (BARs)
that are assigned resources for each device. Each BAR will be enumerated via
a line in the following format:
bar [10] = type Memory, range 32, base 0xda060000, size 131072, enabled
The first value after the
“bar
” prefix in the square brackets is
the offset of the BAR in config space in hexadecimal. The type of a BAR is
one of “Memory”, “Prefetchable Memory”, or
“I/O Port”. The range indicates the maximum address the BAR
decodes. The base and size indicate the start and length of the BAR's
address window, respectively. Finally, the last flag indicates if the BAR is
enabled or disabled.
If the -c
option is supplied,
pciconf
will list any capabilities supported by each
device. Each capability is enumerated via a line in the following
format:
cap 10[40] = PCI-Express 1 root port
The first value after the
“cap
” prefix is the capability ID in
hexadecimal. The second value in the square brackets is the offset of the
capability in config space in hexadecimal. The format of the text after the
equals sign is capability-specific.
Each extended capability is enumerated via a line in a similar format:
ecap 0002[100] = VC 1 max VC0
The first value after the
“ecap
” prefix is the extended
capability ID in hexadecimal. The second value in the square brackets is the
offset of the extended capability in config space in hexadecimal. The format
of the text after the equals sign is capability-specific.
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.
All invocations of pciconf
except for
-l
require a selector of the
form
pci
domain:bus:device:function,
pci
bus:device:function,
or
pci
bus:device.
In case of an abridged form, omitted selector components are assumed to be
0. An optional leading device name followed by @ and an optional final colon
will be ignored; this is so that the first column 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 zero 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
option 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
indicates 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
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.