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| author | Andre Przywara <andre.przywara@amd.com> | 2012-09-04 10:28:07 +0200 |
|---|---|---|
| committer | Rafael J. Wysocki <rjw@sisk.pl> | 2012-09-09 22:05:12 +0200 |
| commit | 615b7300717b9ad5c23d1f391843484fe30f6c12 (patch) | |
| tree | a9773a2bb6ce4d411485402af45dcadf7fbefe28 /Documentation/ABI | |
| parent | ACPI: Add fixups for AMD P-state figures (diff) | |
| download | linux-615b7300717b9ad5c23d1f391843484fe30f6c12.tar.xz linux-615b7300717b9ad5c23d1f391843484fe30f6c12.zip | |
acpi-cpufreq: Add support for disabling dynamic overclocking
One feature present in powernow-k8 that isn't present in acpi-cpufreq
is support for enabling or disabling AMD's core performance boost
technology. This patch adds support to acpi-cpufreq, but also
includes support for Intel's dynamic acceleration.
The original boost disabling sysfs file was per CPU, but acted
globally. Also the naming (cpb) was at least not intuitive.
So lets introduce a single file simply called "boost", which sits
once in /sys/devices/system/cpu/cpufreq.
This should be the only way of using this feature, so add
documentation about the rationale and the usage.
A following patch will re-introduce the cpb knob for compatibility
reasons on AMD CPUs.
Per-CPU boost switching is possible, but not trivial and is thus
postponed to a later patch series.
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Diffstat (limited to 'Documentation/ABI')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-system-cpu | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index 5dab36448b44..6943133afcb8 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -176,3 +176,14 @@ Description: Disable L3 cache indices All AMD processors with L3 caches provide this functionality. For details, see BKDGs at http://developer.amd.com/documentation/guides/Pages/default.aspx + + +What: /sys/devices/system/cpu/cpufreq/boost +Date: August 2012 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: Processor frequency boosting control + + This switch controls the boost setting for the whole system. + Boosting allows the CPU and the firmware to run at a frequency + beyound it's nominal limit. + More details can be found in Documentation/cpu-freq/boost.txt |