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.\" Copyright 2021 Oxide Computer Company
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.Dd July 30, 2021
.Dt USMN 4D
.Os
.Sh NAME
.Nm usmn
.Nd AMD SMN user access driver
.Sh SYNOPSIS
.Pa /devices/pseudo/amdzen@0/usmn@2:usmn.*
.Sh DESCRIPTION
The
.Nm
driver provides the ability to read and write data from the AMD System
Management Network
.Pq SMN
on AMD Family 17h
.Pq Zen, Zen+, and Zen 2
and AMD Family 19h
.Pq Zen 3
processors.
.Pp
This driver is intended strictly for facilitating platform development
and is not recommended for systems that aren't doing kernel and platform
development on AMD Zen platforms.
Arbitrary writes to the SMN can severely damage and destabilize the system.
If you do not need access to the SMN, then this driver should not be
present on the system.
.Sh SEE ALSO
.Xr amdzen 4D ,
.Xr zen_udf 4D