Difference between revisions of "CPU Freq"

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(Add Category Power Management)
 
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   Clock scaling allows you to change the clock speed of the running CPU on the fly.
 
   Clock scaling allows you to change the clock speed of the running CPU on the fly.
 
   This is a nice method to save battery power, because the lower the clock speed, the less
 
   This is a nice method to save battery power, because the lower the clock speed, the less
   power the CPU consumes. [[CPU Freq]] is a generic framework to make architecture implementation
+
   power the CPU consumes. CPU Freq is a generic framework to make architecture implementation
   specifics transparent to a user. Currently, [[CPU Freq]] supports various ARM CPUs (Integrator,
+
   specifics transparent to a user. Currently, CPU Freq supports various ARM CPUs (Integrator,
   SA1100, SA1110), various x86's (AMD [[Power NOW]], VIA Cyrix Longhaul), and various Super H CPUs
+
   SA1100, SA1110), various x86's (AMD Power NOW, VIA Cyrix Longhaul), and various Super H CPUs
 
   (SH-4 7750/7751, SH-3, and so forth). This project also incorporates some work at reverse
 
   (SH-4 7750/7751, SH-3, and so forth). This project also incorporates some work at reverse
 
   engineering support for Intel Speedstep technology.
 
   engineering support for Intel Speedstep technology.
  
 
== Resources ==
 
== Resources ==
* [[CPU Freq]] home page: http://www.advogato.org/proj/CPUFreq/ (it looks a little out-of-date)
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* CPU Freq home page: http://www.advogato.org/proj/CPUFreq/ (it looks a little out-of-date)
 
* Source Forge project for cpufreqd: http://sourceforge.net/projects/cpufreqd/
 
* Source Forge project for cpufreqd: http://sourceforge.net/projects/cpufreqd/
 
* LWN.net article pointing to Documentation post for 2.5.32 kernel: http://lwn.net/Articles/8642/
 
* LWN.net article pointing to Documentation post for 2.5.32 kernel: http://lwn.net/Articles/8642/
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The code in the CELF tree doesn't bear much resemblance to the current patches.
 
The code in the CELF tree doesn't bear much resemblance to the current patches.
 
Note that this whole system appears to be a backport of this feature from the
 
Note that this whole system appears to be a backport of this feature from the
2.5/6 kernel version.
+
2.5/2.6 kernel version.
 +
[[Category:Power Management]]

Latest revision as of 22:01, 6 May 2011

Information about CPU Frequency Scaling.

From the CPUFreq home page:

 Clock scaling allows you to change the clock speed of the running CPU on the fly.
 This is a nice method to save battery power, because the lower the clock speed, the less
 power the CPU consumes. CPU Freq is a generic framework to make architecture implementation
 specifics transparent to a user. Currently, CPU Freq supports various ARM CPUs (Integrator,
 SA1100, SA1110), various x86's (AMD Power NOW, VIA Cyrix Longhaul), and various Super H CPUs
 (SH-4 7750/7751, SH-3, and so forth). This project also incorporates some work at reverse
 engineering support for Intel Speedstep technology.

Resources

Code Status

The code in the CELF tree doesn't bear much resemblance to the current patches. Note that this whole system appears to be a backport of this feature from the 2.5/2.6 kernel version.