freebsd-skq/usr.sbin/pciconf/pciconf.8
jhb 4647004788 Add a new -B flag for use with list mode (-l) that lists details about
bridges.  Currently this includes information about what resources a
bridge decodes on the upstream side for use by downstream devices including
bus numbers, I/O port resources, and memory resources.  Windows and bus
ranges are enumerated for both PCI-PCI bridges and PCI-CardBus bridges.

To simplify the implementation, all enumeration is done by reading the
appropriate config space registers directly rather than querying the
bridge driver in the kernel via new ioctls.  This does result in a few
limitations.

First, an unimplemented window in a PCI-PCI bridge cannot be accurately
detected as accurate detection requires writing to the window base
register.  That is not safe for pciconf(8).  Instead, this assumes that
any window where both the base and limit read as all zeroes is
unimplemented.

Second, the PCI-PCI bridge driver in a tree has a few quirks for
PCI-PCI bridges that use subtractive decoding but do not indicate that
via the progif config register.  The list of quirks is duplicated in
pciconf's source.

Reviewed by:	imp
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D4171
2015-11-23 23:48:07 +00:00

371 lines
9.6 KiB
Groff

.\" Copyright (c) 1997
.\" Stefan Esser <se@FreeBSD.org>. All rights reserved.
.\"
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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.\" $FreeBSD$
.\"
.Dd November 23, 2015
.Dt PCICONF 8
.Os
.Sh NAME
.Nm pciconf
.Nd diagnostic utility for the PCI bus
.Sh SYNOPSIS
.Nm
.Fl l Oo Fl BbceVv Oc Op Ar device
.Nm
.Fl a Ar device
.Nm
.Fl r Oo Fl b | h Oc Ar device addr Ns Op : Ns Ar addr2
.Nm
.Fl w Oo Fl b | h Oc Ar device addr value
.Sh DESCRIPTION
The
.Nm
utility provides a command line interface to functionality provided by the
.Xr pci 4
.Xr ioctl 2
interface.
As such, some of the functions are only available to users with write
access to
.Pa /dev/pci ,
normally only the super-user.
.Pp
With the
.Fl l
option,
.Nm
lists PCI devices in the following format:
.Bd -literal
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
.Ed
.Pp
The first column gives the
driver name, unit number, and selector .
If there is no driver attached to the
.Tn PCI
device in question, the driver name will be
.Dq none .
Unit numbers for detached devices start at zero and are incremented for
each detached 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
.Tn 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.
.Pp
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
.Tn PCI
to
.Tn PCI
bridges, and 2 for
.Tn PCI
to
.Tn CardBus
bridges.
If the most significant bit
of the header type register is set for
function 0 of a
.Tn PCI
device, it is a
.Em multi-function
device, which contains several (similar or independent) functions on
one chip.
.Pp
If the
.Fl B
option is supplied,
.Nm
will list additional information for
.Tn PCI
to
.Tn PCI
and
.Tn PCI
to
.Tn CardBus
bridges,
specifically the resource ranges decoded by the bridge for use by devices
behind the bridge.
Each bridge lists a range of bus numbers handled by the bridge and its
downstream devices.
Memory and I/O port decoding windows are enumerated via a line in the
following format:
.Bd -literal
window[1c] = type I/O Port, range 16, addr 0x5000-0x8fff, enabled
.Ed
.Pp
The first value after the
.Dq Li window
prefix in the square brackets is the offset of the decoding window in
config space in hexadecimal.
The type of a window is one of
.Dq Memory ,
.Dq Prefetchable Memory ,
or
.Dq I/O Port .
The range indicates the binary log of the maximum address the window decodes.
The address field indicates the start and end addresses of the decoded range.
Finally, the last flag indicates if the window is enabled or disabled.
.Pp
If the
.Fl b
option is supplied,
.Nm
will list any base address registers
.Pq BARs
that are assigned resources for each device.
Each BAR will be enumerated via a line in the following format:
.Bd -literal
bar [10] = type Memory, range 32, base 0xda060000, size 131072, enabled
.Ed
.Pp
The first value after the
.Dq Li 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
.Dq Memory ,
.Dq Prefetchable Memory ,
or
.Dq I/O Port .
The range indicates the binary log of 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.
.Pp
If the
.Fl c
option is supplied,
.Nm
will list any capabilities supported by each device.
Each capability is enumerated via a line in the following format:
.Bd -literal
cap 10[40] = PCI-Express 1 root port
.Ed
.Pp
The first value after the
.Dq Li 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.
.Pp
Each extended capability is enumerated via a line in a similar format:
.Bd -literal
ecap 0002[100] = VC 1 max VC0
.Ed
.Pp
The first value after the
.Dq Li 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.
.Pp
If the
.Fl e
option is supplied,
.Nm
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.
.Pp
If the
.Fl v
option is supplied,
.Nm
will attempt to load the vendor/device information database, and print
vendor, device, class and subclass identification strings for each device.
.Pp
If the
.Fl V
option is supplied,
.Nm
will list any vital product data
.Pq VPD
provided by each device.
Each VPD keyword is enumerated via a line in the following format:
.Bd -literal
VPD ro PN = '110114640C0 '
.Ed
.Pp
The first string after the
.Dq Li VPD
prefix indicates if the keyword is read-only
.Dq ro
or read-write
.Dq rw .
The second string provides the keyword name.
The text after the the equals sign lists the value of the keyword which is
usually an ASCII string.
.Pp
If the optional
.Ar device
argument is given with the
.Fl l
flag,
.Nm
will only list details about a single device instead of all devices.
.Pp
All invocations of
.Nm
except for
.Fl l
require a
.Ar device .
The device can be identified either by a device name if the device is
attached to a driver or by a selector.
Selectors identify a PCI device by its address in PCI config space and
can take one of the following forms:
.Pp
.Bl -bullet -offset indent -compact
.It
.Li pci Ns Va domain Ns \&: Ns Va bus Ns \&: Ns Va device Ns \&: \
Ns Va function Ns
.It
.Li pci Ns Va bus Ns \&: Ns Va device Ns \&: Ns Va function Ns
.It
.Li pci Ns Va bus Ns \&: Ns Va device Ns
.El
.Pp
In the 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
.Nm
.Fl l
can be used without modification.
All numbers are base 10.
.Pp
With the
.Fl a
flag,
.Nm
determines whether any driver has been assigned to the device
identified by
.Ar selector .
An exit status of zero indicates that the device has a driver;
non-zero indicates that it does not.
.Pp
The
.Fl r
option reads a configuration space register at byte offset
.Ar addr
of device
.Ar selector
and prints out its value in hexadecimal.
The optional second address
.Ar addr2
specifies a range to read.
The
.Fl w
option writes the
.Ar value
into a configuration space register at byte offset
.Ar addr
of device
.Ar selector .
For both operations, the flags
.Fl b
and
.Fl h
select the width of the operation;
.Fl b
indicates a byte operation, and
.Fl h
indicates a halfword (two-byte) operation.
The default is to read or
write a longword (four bytes).
.Sh ENVIRONMENT
PCI vendor and device information is read from
.Pa /usr/local/share/pciids/pci.ids .
If that file is not present, it is read from
.Pa /usr/share/misc/pci_vendors .
This path can be overridden by setting the environment variable
.Ev PCICONF_VENDOR_DATABASE .
.Sh SEE ALSO
.Xr ioctl 2 ,
.\" .Xr pci 4 ,
.Xr devinfo 8 ,
.Xr kldload 8
.Sh HISTORY
The
.Nm
utility appeared first in
.Fx 2.2 .
The
.Fl a
option was added for
.Tn PCI
KLD support in
.Fx 3.0 .
.Sh AUTHORS
.An -nosplit
The
.Nm
utility was written by
.An Stefan Esser
and
.An Garrett Wollman .
.Sh BUGS
The
.Fl b
and
.Fl h
options are implemented in
.Nm ,
but not in the underlying
.Xr ioctl 2 .
.Pp
It might be useful to give non-root users access to the
.Fl a
and
.Fl r
options.
But only root will be able to execute a
.Nm kldload
to provide the device with a driver KLD, and reading of configuration space
registers may cause a failure in badly designed
.Tn PCI
chips.