est(4) man page update to document the exposed sysctl r/o variables

available to the user.  Should be applicable to all branches and versions
where est(4) exists.

thanks to gjb for reviewing and suggesting nits

Reviewed by:	gjb@
MFC after:	2 weeks

1 files changed, 25 insertions, 2 deletions

diff --git a/share/man/man4/est.4 b/share/man/man4/est.4
index f1b5832..98c0504 100644
--- a/share/man/man4/est.4
+++ b/share/man/man4/est.4
@@ -25,7 +25,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd June 12, 2012
+.Dd October 18 , 2012
 .Dt EST 4
 .Os
 .Sh NAME
@@ -63,13 +63,36 @@ behavior.
 .Bl -tag -width indent
 .It hw.est.msr_info
 Attempt to infer information from direct probing of the msr.
-Should only be used in diagnostic cases
+Should only be used in diagnostic cases.
 .Pq default 0
 .It hw.est.strict
 Validate frequency requested is accepted by the cpu when set.
 It appears that this will only work on single core cpus.
 .Pq default 0
 .El
+.Sh SYSCTL VARIABLES
+The following
+.Xr sysctl 8
+values are available
+.Bl -tag -width indent
+.It Va dev.est.%d.\%desc
+Description of support, almost always Enhanced SpeedStep Frequency Control.
+.It dev.est.0.%desc: Enhanced SpeedStep Frequency Control
+.It Va dev.est.%d.\%driver
+Driver in use, always est.
+.It dev.est.0.%driver: est
+.It Va dev.est.%d.\%parent
+.It dev.est.0.%parent: cpu0
+The cpu that is exposing these frequencies.
+For example
+.Va cpu0 .
+.It Va dev.est.%d.freq_settings .
+The valid frequencies that are allowed by this CPU and their step values.
+.It dev.est.0.freq_settings: 2201/45000 2200/45000 2000/39581 1900/37387 
+1800/34806 1700/32703 1600/30227 1500/28212 1400/25828 1300/23900 1200/21613 
+1100/19775 1000/17582 900/15437 800/13723
+.Pp
+.El
 .Sh DIAGNOSTICS
 .Bl -diag
 .It "est%d: <Enhanced SpeedStep Frequency Control> on cpu%d"