ACPI: thermal: create "thermal.nocrt" to disable critical actions
thermal.nocrt=1 disables actions on _CRT and _HOT
ACPI thermal zone trip-points. They will be marked
as <disabled> in /proc/acpi/thermal_zone/*/trip_points.
There are two cases where this option is used:
1. Debugging a hot system crossing valid trip point.
If your system fan is spinning at full speed,
be sure that the vent is not clogged with dust.
Many laptops have very fine thermal fins that are easily blocked.
Check that the processor fan-sink is properly seated,
has the proper thermal grease, and is really spinning.
Check for fan related options in BIOS SETUP.
Sometimes there is a performance vs quiet option.
Defaults are generally the most conservative.
If your fan is not spinning, yet /proc/acpi/fan/
has files in it, please file a Linux/ACPI bug.
WARNING: you risk shortening the lifetime of your
hardware if you use this parameter on a hot system.
Note that this refers to all system components,
including the disk drive.
2. Working around a cool system crossing critical
trip point due to erroneous temperature reading.
Try again with CONFIG_HWMON=n
There is known potential for conflict between the
the hwmon sub-system and the ACPI BIOS.
If this fixes it, notify lm-sensors@lm-sensors.org
and linux-acpi@vger.kernel.org
Otherwise, file a Linux/ACPI bug, or notify
just linux-acpi@vger.kernel.org.
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 52e1c2d..4c7d277 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1820,6 +1820,10 @@
thash_entries= [KNL,NET]
Set number of hash buckets for TCP connection
+ thermal.nocrt= [HW,ACPI]
+ Set to disable actions on ACPI thermal zone
+ critical and hot trip points.
+
thermal.off= [HW,ACPI]
1: disable ACPI thermal control