1.\" Copyright (c) 2003 Takanori Watanabe. 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD: head/share/man/man4/acpi_thermal.4 167670 2007-03-18 00:57:07Z njl $ 26.\" 27.Dd May 16, 2015 28.Dt ACPI_THERMAL 4 29.Os 30.Sh NAME 31.Nm acpi_thermal 32.Nd ACPI thermal management subsystem 33.Sh SYNOPSIS 34.Cd "device acpi" 35.Sh DESCRIPTION 36The 37.Nm 38driver provides the thermal management features of the ACPI module. 39This driver has a 40.Xr sysctl 8 41interface and a 42.Xr devd 8 43notification interface. 44The sysctls export properties of each ACPI thermal zone object. 45.Pp 46There can be multiple thermal zones in a system. 47For example, each CPU and the enclosure could all be separate thermal 48zones, each with its own setpoints and cooling devices. 49Thermal zones are numbered sequentially in the order they appear in 50the AML. 51.Pp 52The 53.Nm 54driver also activates the active cooling system according to 55each thermal zone's setpoints. 56.Sh SYSCTL VARIABLES 57.Bl -tag -width indent 58.It Va hw.acpi.thermal.min_runtime 59Number of seconds to continue active cooling once started. 60A new active cooling level will not be selected until this interval expires. 61.It Va hw.acpi.thermal.polling_rate 62Number of seconds between polling the current temperature. 63If set to 0, temperature polling is deactivated. 64Use with care, strange hardware-specific issues can occur when a wrong 65value is set. 66Some systems will always report the same temperature when the polling 67period is too low. 68Also ACPI based fan control can stop working when the wrong value is 69set here. 70.It Va hw.acpi.thermal.user_override 71If set to 1, allow user override of various setpoints (below). 72The original values for these settings are obtained from the BIOS and 73system overheating and possible damage could occur if changed. 74Default is 0 (no override). 75.It Va hw.acpi.thermal.tz%d.active 76Current active cooling system state. 77If this is non-negative, the appropriate _AC%d object is running. 78Set this value to the desired active cooling level to force 79the corresponding fan object to the appropriate level. 80.It Va hw.acpi.thermal.tz%d.passive_cooling 81If set to 1, passive cooling is enabled. 82.\"It does cooling without fans using 83.\".Xr cpufreq 4 84.\"as the mechanism for controlling CPU speed. 85Default is enabled for tz0 where it is available. 86.It Va hw.acpi.thermal.tz%d.thermal_flags 87Current thermal zone status. 88These are bit-masked values. 89.It Va hw.acpi.thermal.tz%d.temperature 90Current temperature for this zone. 91.It Va hw.acpi.thermal.tz%d._PSV 92Temperature to start passive cooling by throttling down CPU, etc. 93This value can be overridden by the user. 94.It Va hw.acpi.thermal.tz%d._HOT 95Temperature to start critical suspend to disk (S4). 96This value can be overridden by the user. 97.It Va hw.acpi.thermal.tz%d._CRT 98Temperature to start critical shutdown (S5). 99This value can be overridden by the user. 100.It Va hw.acpi.thermal.tz%d._ACx 101Temperatures at which to switch to the corresponding active cooling 102level. 103The lower the _ACx value, the higher the cooling power. 104.El 105.Pp 106All temperatures are printed in Celsius. 107Values can be set in Celsius (by providing a trailing 108.Qq C ) 109or Kelvin (by leaving off any trailing letter). 110When setting a value by 111.Xr sysctl 8 , 112do not specify a trailing decimal (i.e., 90C instead of 90.0C). 113.Sh NOTIFIES 114Notifies are passed to userland via 115.Xr devd 8 . 116See 117.Pa /etc/devd.conf 118and 119.Xr devd.conf 5 120for examples. 121The 122.Nm 123driver sends events with the following attributes: 124.Pp 125.Bl -tag -width "subsystem" -compact 126.It system 127.Li ACPI 128.It subsystem 129.Li Thermal 130.It type 131The fully qualified thermal zone object path as in the ASL. 132.It notify 133An integer designating the event: 134.Pp 135.Bl -tag -width indent -compact 136.It Li 0x80 137Current temperature has changed. 138.It Li 0x81 139One or more trip points (_ACx, _PSV) have changed. 140.It Li 0x82 141One or more device lists (_ALx, _PSL, _TZD) have changed. 142.It Li 0xcc 143Non-standard notify that the system will shutdown if the temperature 144stays above _CRT or _HOT for one more poll cycle. 145.El 146.El 147.Sh SEE ALSO 148.Xr acpi 4 , 149.\".Xr cpufreq 4 , 150.Xr acpidump 8 151.Sh AUTHORS 152.An -nosplit 153.An Michael Smith 154.Pp 155This manual page was written by 156.An Takanori Watanabe . 157