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PCICONF(8)		  BSD System Manager's Manual		    PCICONF(8)

     pciconf --	diagnostic utility for the PCI bus

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

     The pciconf utility provides a command line interface to functionality
     provided by the pci(4) ioctl(2) interface.	 As such, some of the func-
     tions 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 ques-
     tion, the device name will	be "none".  Unit numbers for unconfigured de-
     vices 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 sub-
     vendorid 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 reg-
     ister is set for function 0 of a PCI device, it is	a multi-function de-
     vice, which contains several (similar or independent) functions on	one

     If	the -b option is supplied, pciconf will	list any base address regis-
     ters (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 off-
     set 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 sup-
     ported by each device.  Each capability will be 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 hexadeci-
     mal.  The second value in the square brackets is the offset of the	capa-
     bility in config space in hexadecimal.  The format	of the text after the
     equals sign is capability-specific.

     If	the -e option is supplied, pciconf will	list any errors	reported for
     this device in standard PCI error registers.  Errors are checked for in
     the PCI status register, the PCI-express device status register, and the
     Advanced Error Reporting status registers.

     If	the -v option is supplied, pciconf will	attempt	to load	the vendor/de-
     vice 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
     pcidomain:bus:device:function, pcibus:device:function, or pcibus:device.
     In	case of	an abrigded form, omitted selector components are assumed to
     be	0.  An optional	leading	device name followed by	@ and an optional fi-
     nal 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

     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.

     ioctl(2), devinfo(8), kldload(8)

     The pciconf utility appeared first	in FreeBSD 2.2.	 The -a	option was
     added for PCI KLD support in FreeBSD 3.0.

     The pciconf utility was written by	Stefan Esser and Garrett Wollman.

     The -b and	-h options are implemented in pciconf, but not in the underly-
     ing ioctl(2).

     It	might be useful	to give	non-root users access to the -a	and -r op-
     tions.  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				 June 1, 2012				   BSD


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