xref: /illumos-gate/usr/src/man/man4d/usmn.4d (revision 9174bfaa08ca3aa4c0a12e840c4bd4f2570237a0)
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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