Improve frequency scaling-related manual pages
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e9c04a6f 32.Dd October 10, 2014
231d9860 33.Dt POWERNOW 4
fb5b3747 34.Os
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35.Sh NAME
36.Nm powernow
37.Nd PowerNow! Technology support
38.Sh SYNOPSIS
39To compile this driver into the kernel, place the following line in your
40kernel configuration file:
41.Bd -ragged -offset indent
42.Cd "options CPU_ENABLE_POWERNOW"
43.Ed
44.Pp
45To load this driver as a module at boot time, place the following line in
46.Xr loader.conf 5 :
47.Bd -literal -offset indent
48powernow_load="YES"
49.Ed
50.Sh DESCRIPTION
51The
52.Nm
53driver provides support for the
54.Tn PowerNow! Technology
55present in AMD K8 CPUs.
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56Please note that
57.Xr powerd 8
58should be preferred if it is working properly on your system.
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59.Pp
60If the CPU is supported
61.Nm
62creates the following variables in the
63.Va machdep.powernow
64branch of the
65.Xr sysctl 3
66MIB.
67.Bl -tag -width ".Va frequency.available" -offset indent
68.It Va frequency.available
8e5e11bf 69The list of frequencies supported by
231d9860 70.Nm
8e5e11bf 71for the CPU (read only).
231d9860 72.It Va frequency.current
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73The current CPU frequency (read only).
74.It Va frequency.target
75The target CPU frequency (read/write).
231d9860 76.El
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77.Sh SEE ALSO
78.Xr est 4 ,
79.Xr powerd 8
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80.Sh HISTORY
81The
82.Nm
83driver first appeared in
84.Dx 2.3 .