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39 .Nd Enhanced SpeedStep Technology support
41 To compile this driver into the kernel, place the following line in your
42 kernel configuration file:
43 .Bd -ragged -offset indent
44 .Cd "options CPU_ENABLE_EST"
47 To load this driver as a module at boot time, place the following line in
49 .Bd -literal -offset indent
55 driver provides support for the
56 .Tn Enhanced SpeedStep Technology
57 present in newer CPUs.
59 If the CPU is supported
61 creates the following variables in the
66 .Bl -tag -width ".Va frequency.available" -offset indent
67 .It Va frequency.available
68 (read only) The list of frequencies supported by
71 .It Va frequency.current
72 (read only) The currect CPU frequency.
73 .It Va frequency.target
74 (read/write) The target CPU frequency.
77 An associated userland daemon which is part of the
81 can be used to dynamically set the CPU frequency depending on utilization.
85 driver first appeared in