This commit is contained in:
jruoho 2010-12-30 12:06:53 +00:00
parent a5a73b2a05
commit 704b4b5b77
1 changed files with 30 additions and 18 deletions

View File

@ -1,4 +1,4 @@
.\" $NetBSD: acpicpu.4,v 1.20 2010/12/20 09:11:37 wiz Exp $
.\" $NetBSD: acpicpu.4,v 1.21 2010/12/30 12:06:53 jruoho Exp $
.\"
.\" Copyright (c) 2010 Jukka Ruohonen <jruohonen@iki.fi>
.\" All rights reserved.
@ -24,7 +24,7 @@
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.Dd December 20, 2010
.Dd December 30, 2010
.Dt ACPICPU 4
.Os
.Sh NAME
@ -185,11 +185,11 @@ dynamically scale the presently supported maximum or minimum clock frequency.
For example, if
.Xr acpiacad 4
is disconnected, the maximum available frequency may be lowered.
Currently the
By default,
the
.Nx
implementation reacts to these events by imposing the dynamic maximum, but
.Nm
does not take any actions to manipulate the frequencies by itself.
implementation may manipulate the frequencies
according to the notifications from the firmware.
.Ss T-states
Processor T-states, or
.Dq throttling states ,
@ -250,17 +250,6 @@ the system is in the highest-power P-state and
a high temperature situation exists.
After the temperatures have returned to non-critical levels,
the modulation ceases.
.Ss Statistics
The
.Nm
driver uses event counters to track the times
a processor has entered a given state.
It is possible to view the statistics by using
.Xr vmstat 1
(with the
.Fl e
flag).
Note that valid per-CPU data is available only for C-states.
.Ss System Control Variables
The
.Nm
@ -277,7 +266,30 @@ or
.Ic machdep.powernow .
Please note that future versions of
.Nm
may however remove the system control variables without further notice.
may however remove these system control variables without further notice.
.Pp
In addition, the following two variables are available.
.Bl -tag -width "hw.acpi.cpu.dynamic" -offset indent
.It Ic hw.acpi.cpu.dynamic
A boolean that controls whether the states are allowed to change dynamically.
When enabled, C-, P-, and T-states may all change at runtime, and
.Nm
may also take actions based on requests from the firmware.
.It Ic hw.acpi.cpu.passive
A boolean that enables or disables automatic processor thermal management via
.Xr acpitz 4 .
.El
.Ss Statistics
The
.Nm
driver uses event counters to track the times
a processor has entered a given state.
It is possible to view the statistics by using
.Xr vmstat 1
(with the
.Fl e
flag).
Note that valid per-CPU data is available only for C-states.
.Sh COMPATIBILITY
The
.Nm