xref: /illumos-gate/usr/src/man/man4d/usmn.4d (revision b02947bf393d39f68e6c7fa8ccb98688f7f9c407)
1.\"
2.\" This file and its contents are supplied under the terms of the
3.\" Common Development and Distribution License ("CDDL"), version 1.0.
4.\" You may only use this file in accordance with the terms of version
5.\" 1.0 of the CDDL.
6.\"
7.\" A full copy of the text of the CDDL should have accompanied this
8.\" source.  A copy of the CDDL is also available via the Internet at
9.\" http://www.illumos.org/license/CDDL.
10.\"
11.\"
12.\" Copyright 2021 Oxide Computer Company
13.\"
14.Dd July 30, 2021
15.Dt USMN 4D
16.Os
17.Sh NAME
18.Nm usmn
19.Nd AMD SMN user access driver
20.Sh SYNOPSIS
21.Pa /devices/pseudo/amdzen@0/usmn@2:usmn.*
22.Sh DESCRIPTION
23The
24.Nm
25driver provides the ability to read and write data from the AMD System
26Management Network
27.Pq SMN
28on AMD Family 17h
29.Pq Zen, Zen+, and Zen 2
30and AMD Family 19h
31.Pq Zen 3
32processors.
33.Pp
34This driver is intended strictly for facilitating platform development
35and is not recommended for systems that aren't doing kernel and platform
36development on AMD Zen platforms.
37Arbitrary writes to the SMN can severely damage and destabilize the system.
38If you do not need access to the SMN, then this driver should not be
39present on the system.
40.Sh SEE ALSO
41.Xr amdzen 4D ,
42.Xr zen_udf 4D
43