Add apic(4) man page, now mostly to cover its event timer functionality.

This commit is contained in:
Alexander Motin 2011-12-20 13:49:52 +00:00
parent df6faa4c5c
commit 73889c808a
6 changed files with 88 additions and 4 deletions

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@ -38,6 +38,7 @@ MAN= aac.4 \
${_amdtemp.4} \
amr.4 \
an.4 \
${_apic.4} \
arcmsr.4 \
${_asmc.4} \
asr.4 \
@ -673,6 +674,7 @@ _acpi_sony.4= acpi_sony.4
_acpi_toshiba.4=acpi_toshiba.4
_acpi_wmi.4= acpi_wmi.4
_aesni.4= aesni.4
_apic.4= apic.4
_atrtc.4= atrtc.4
_attimer.4= attimer.4
_aibs.4= aibs.4

78
share/man/man4/apic.4 Normal file
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@ -0,0 +1,78 @@
.\" Copyright (c) 2011 Alexander Motin <mav@FreeBSD.org>
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" $FreeBSD$
.\"
.Dd December 20, 2011
.Dt APIC 4
.Os
.Sh NAME
.Nm apic
.Nd Advanced Programmable Interrupt Controller (APIC) driver
.Sh SYNOPSIS
This driver is a mandatory part of amd64 kernel.
To compile this driver into i386 or pc98 kernel,
place the following line in your
kernel configuration file:
.Bd -ragged -offset indent
.Cd "device apic"
.Ed
.Pp
The following tunable is settable from the
.Xr loader 8 :
.Bl -ohang
.It Va hint.apic. Ns Ar X Ns Va .clock
controls event timers functionality support. Setting to 0, disables it.
Default value is 1.
.It Va hint.apic. Ns Ar X Ns Va .disabled
Set this to 1 to disable APIC support, falling back to the legacy PIC.
.El
.Sh DESCRIPTION
There are two components in the Intel APIC system, the local APIC (LAPIC)
and the I/O APIC.
There is one LAPIC in each CPU in the system.
There is typically one I/O APIC for each peripheral bus in the system.
.Pp
LAPICs manage all external and interrupts for specific processor in an
SMP system.
In addition, they are able to accept and generate inter-processor interrupts
(IPIs).
.Pp
I/O APICs contain a redirection table, which is used to route the interrupts
they receive from peripheral buses to one or more local APICs.
.Pp
Each LAPIC includes one 32-bit programable timer.
This driver uses them to supply kernel with one event timer named "LAPIC".
Event timer provided by the driver supports both one-shot an periodic modes.
Because of LAPIC nature it is per-CPU.
The timer frequency is not reported by the platform and so automatically
measured by the driver on the first use.
Depending on CPU model this timer may stop in C3 and deeper CPU sleep states.
Driver automatically adjusts event timer priority and reports it to prevent
entering dangerous sleep states when it is used.
.Sh SEE ALSO
.Xr atrtc 4 ,
.Xr attimer 4 ,
.Xr eventtimers 4 ,
.Xr hpet 4

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@ -51,6 +51,7 @@ divisors.
.Pp
Event timer provided by the driver is irrelevant to CPU power states.
.Sh SEE ALSO
.Xr apic 4 ,
.Xr attimer 4 ,
.Xr hpet 4 ,
.Xr eventtimers 4
.Xr eventtimers 4 ,
.Xr hpet 4

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@ -70,6 +70,7 @@ functionality is disabled.
.Pp
Event timer provided by the driver is irrelevant to CPU power states.
.Sh SEE ALSO
.Xr apic 4 ,
.Xr atrtc 4 ,
.Xr hpet 4 ,
.Xr eventtimers 4
.Xr eventtimers 4 ,
.Xr hpet 4

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@ -145,6 +145,7 @@ and runs in periodic mode, this option has no effect - all interrupts are
always generating.
.El
.Sh SEE ALSO
.Xr apic 4 ,
.Xr atrtc 4 ,
.Xr attimer 4 ,
.Xr hpet 4 ,

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@ -94,6 +94,7 @@ group is bound to specific CPU core. This is possible only when each
of these comparators has own unsharable IRQ.
.Sh SEE ALSO
.Xr acpi 4 ,
.Xr apic 4 ,
.Xr atrtc 4 ,
.Xr attimer 4 ,
.Xr eventtimers 4