xref: /freebsd/share/man/man4/ntb_transport.4 (revision d8a0fe102c0cfdfcd5b818f850eff09d8536c9bc)
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26.\" $FreeBSD$
27.\"
28.Dd September 2, 2017
29.Dt NTB_TRANSPORT 4
30.Os
31.Sh NAME
32.Nm ntb_transport
33.Nd Packet-oriented transport for Non-Transparent Bridges
34.Sh SYNOPSIS
35To compile this driver into your kernel,
36place the following lines in your kernel configuration file:
37.Bd -ragged -offset indent
38.Cd "device ntb"
39.Cd "device ntb_transport"
40.Ed
41.Pp
42Or, to load the driver as a module at boot, place the following line in
43.Xr loader.conf 5 :
44.Bd -literal -offset indent
45ntb_transport_load="YES"
46.Ed
47.Pp
48The following tunables are settable from the
49.Xr loader 8 :
50.Bl -ohang
51.It Va hw.ntb_transport.debug_level
52Driver debug level.
53The default value is 0, higher means more verbose.
54.It Va hint.ntb_transport. Ns Ar X Ns Va .config
55Configures a set of the transport consumers, separated by commas.
56Each consumer can be configured as: "[<name>][:<queues>]", where:
57.Va name
58is a name of the driver to attach (empty means any),
59.Va queues
60is a number of queues to allocate (empty means automatic).
61The default configuration is empty string, which means single consumer
62with one queue per memory window, allowing any driver to attach.
63.El
64.Sh DESCRIPTION
65The
66.Nm
67driver attaches on top of the
68.Nm ntb
69driver to utilize its resources to create a set of bidirectional queues,
70delivering packets between the systems.
71The primary purpose of this driver is to be used by
72.Nm if_ntb
73network interface, but other consumers may also be developed using KPI.
74.Pp
75Each
76.Nm
77require from underlying
78.Nm ntb
79instance:
80.Bl -bullet -compact
81.It
821 or more memory windows;
83.It
846 scratchpads, plus 2 more for each additional memory window;
85.It
861 doorbell for each memory window or configured queue.
87.El
88.Sh SEE ALSO
89.Xr if_ntb 4 ,
90.Xr ntb 4 ,
91.Xr ntb_hw_intel 4 ,
92.Xr ntb_hw_plx 4
93.Sh AUTHORS
94.An -nosplit
95The
96.Nm
97driver was developed by Intel and originally written by
98.An Carl Delsey Aq Mt carl@FreeBSD.org .
99Later improvements were done by
100.An Conrad E. Meyer Aq Mt cem@FreeBSD.org
101and
102.An Alexander Motin Aq Mt mav@FreeBSD.org .
103