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  • Rafael J. Wysocki's avatar
    cpufreq: intel_pstate: Operation mode control from sysfs · fb1fe104
    Rafael J. Wysocki authored
    
    
    Make it possible to change the operation mode of intel_pstate with
    the help of a new sysfs attribute called "status".
    
    There are three possible configurations that can be selected using
    this attribute:
    
     "off"     - The driver is not in use at this time.
     "active"  - The driver works as a P-state governor (default).
     "passive" - The driver works as a regular cpufreq one and collaborates
                 with the generic cpufreq governors (it sets P-states as
                 requested by those governors).  [This is the same mode
                 the driver can be started in by passing intel_pstate=passive
                 in the kernel command line.]
    
    The current setting is returned by reads from this attribute.  Writing
    one of the above strings to it changes the operation mode as indicated
    by that string, if possible.
    
    If HW-managed P-states (HWP) feature is enabled, it is not possible
    to change the driver's operation mode and attempts to write to this
    attribute will fail.
    
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    fb1fe104