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authorJiri Kosina <jkosina@suse.cz>2010-08-10 13:22:08 +0200
committerJiri Kosina <jkosina@suse.cz>2010-08-10 13:22:08 +0200
commitfb8231a8b139035476f2a8aaac837d0099b66dad (patch)
tree2875806beb96ea0cdab292146767a5085721dc6a /Documentation/hwmon/pkgtemp
parent426d31071ac476ea62c62656b242930c17b58c00 (diff)
parentf6cec0ae58c17522a7bc4e2f39dae19f199ab534 (diff)
Merge branch 'master' into for-next
Conflicts: arch/arm/mach-omap1/board-nokia770.c
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+Kernel driver pkgtemp
+======================
+
+Supported chips:
+ * Intel family
+ Prefix: 'pkgtemp'
+ CPUID:
+ Datasheet: Intel 64 and IA-32 Architectures Software Developer's Manual
+ Volume 3A: System Programming Guide
+
+Author: Fenghua Yu
+
+Description
+-----------
+
+This driver permits reading package level temperature sensor embedded inside
+Intel CPU package. The sensors can be in core, uncore, memory controller, or
+other components in a package. The feature is first implemented in Intel Sandy
+Bridge platform.
+
+Temperature is measured in degrees Celsius and measurement resolution is
+1 degree C. Valid temperatures are from 0 to TjMax degrees C, because the actual
+value of temperature register is in fact a delta from TjMax.
+
+Temperature known as TjMax is the maximum junction temperature of package.
+We get this from MSR_IA32_TEMPERATURE_TARGET. If the MSR is not accessible,
+we define TjMax as 100 degrees Celsius. At this temperature, protection
+mechanism will perform actions to forcibly cool down the package. Alarm
+may be raised, if the temperature grows enough (more than TjMax) to trigger
+the Out-Of-Spec bit. Following table summarizes the exported sysfs files:
+
+temp1_input - Package temperature (in millidegrees Celsius).
+temp1_max - All cooling devices should be turned on.
+temp1_crit - Maximum junction temperature (in millidegrees Celsius).
+temp1_crit_alarm - Set when Out-of-spec bit is set, never clears.
+ Correct CPU operation is no longer guaranteed.