Documentation/ABI/testing/sysfs-class-powercap

   1 What:           /sys/class/powercap/
   2 Date:           September 2013
   3 KernelVersion:  3.13
   4 Contact:        linux-pm@vger.kernel.org
   5 Description:
   6                 The powercap/ class sub directory belongs to the power cap
   7                 subsystem. Refer to
   8                 Documentation/power/powercap/powercap.txt for details.
   9
  10 What:           /sys/class/powercap/<control type>
  11 Date:           September 2013
  12 KernelVersion:  3.13
  13 Contact:        linux-pm@vger.kernel.org
  14 Description:
  15                 A <control type> is a unique name under /sys/class/powercap.
  16                 Here <control type> determines how the power is going to be
  17                 controlled. A <control type> can contain multiple power zones.
  18
  19 What:           /sys/class/powercap/<control type>/enabled
  20 Date:           September 2013
  21 KernelVersion:  3.13
  22 Contact:        linux-pm@vger.kernel.org
  23 Description:
  24                 This allows to enable/disable power capping for a "control type".
  25                 This status affects every power zone using this "control_type.
  26
  27 What:           /sys/class/powercap/<control type>/<power zone>
  28 Date:           September 2013
  29 KernelVersion:  3.13
  30 Contact:        linux-pm@vger.kernel.org
  31 Description:
  32                 A power zone is a single or a collection of devices, which can
  33                 be independently monitored and controlled. A power zone sysfs
  34                 entry is qualified with the name of the <control type>.
  35                 E.g. intel-rapl:0:1:1.
  36
  37 What:           /sys/class/powercap/<control type>/<power zone>/<child power zone>
  38 Date:           September 2013
  39 KernelVersion:  3.13
  40 Contact:        linux-pm@vger.kernel.org
  41 Description:
  42                 Power zones may be organized in a hierarchy in which child
  43                 power zones provide monitoring and control for a subset of
  44                 devices under the parent. For example, if there is a parent
  45                 power zone for a whole CPU package, each CPU core in it can
  46                 be a child power zone.
  47
  48 What:           /sys/class/powercap/.../<power zone>/name
  49 Date:           September 2013
  50 KernelVersion:  3.13
  51 Contact:        linux-pm@vger.kernel.org
  52 Description:
  53                 Specifies the name of this power zone.
  54
  55 What:           /sys/class/powercap/.../<power zone>/energy_uj
  56 Date:           September 2013
  57 KernelVersion:  3.13
  58 Contact:        linux-pm@vger.kernel.org
  59 Description:
  60                 Current energy counter in micro-joules. Write "0" to reset.
  61                 If the counter can not be reset, then this attribute is
  62                 read-only.
  63
  64 What:           /sys/class/powercap/.../<power zone>/max_energy_range_uj
  65 Date:           September 2013
  66 KernelVersion:  3.13
  67 Contact:        linux-pm@vger.kernel.org
  68 Description:
  69                 Range of the above energy counter in micro-joules.
  70
  71
  72 What:           /sys/class/powercap/.../<power zone>/power_uw
  73 Date:           September 2013
  74 KernelVersion:  3.13
  75 Contact:        linux-pm@vger.kernel.org
  76 Description:
  77                 Current power in micro-watts.
  78
  79 What:           /sys/class/powercap/.../<power zone>/max_power_range_uw
  80 Date:           September 2013
  81 KernelVersion:  3.13
  82 Contact:        linux-pm@vger.kernel.org
  83 Description:
  84                 Range of the above power value in micro-watts.
  85
  86 What:           /sys/class/powercap/.../<power zone>/constraint_X_name
  87 Date:           September 2013
  88 KernelVersion:  3.13
  89 Contact:        linux-pm@vger.kernel.org
  90 Description:
  91                 Each power zone can define one or more constraints. Each
  92                 constraint can have an optional name. Here "X" can have values
  93                 from 0 to max integer.
  94
  95 What:           /sys/class/powercap/.../<power zone>/constraint_X_power_limit_uw
  96 Date:           September 2013
  97 KernelVersion:  3.13
  98 Contact:        linux-pm@vger.kernel.org
  99 Description:
 100                 Power limit in micro-watts should be applicable for
 101                 the time window specified by "constraint_X_time_window_us".
 102                 Here "X" can have values from 0 to max integer.
 103
 104 What:           /sys/class/powercap/.../<power zone>/constraint_X_time_window_us
 105 Date:           September 2013
 106 KernelVersion:  3.13
 107 Contact:        linux-pm@vger.kernel.org
 108 Description:
 109                 Time window in micro seconds. This is used along with
 110                 constraint_X_power_limit_uw to define a power constraint.
 111                 Here "X" can have values from 0 to max integer.
 112
 113
 114 What:           /sys/class/powercap/<control type>/.../constraint_X_max_power_uw
 115 Date:           September 2013
 116 KernelVersion:  3.13
 117 Contact:        linux-pm@vger.kernel.org
 118 Description:
 119                 Maximum allowed power in micro watts for this constraint.
 120                 Here "X" can have values from 0 to max integer.
 121
 122 What:           /sys/class/powercap/<control type>/.../constraint_X_min_power_uw
 123 Date:           September 2013
 124 KernelVersion:  3.13
 125 Contact:        linux-pm@vger.kernel.org
 126 Description:
 127                 Minimum allowed power in micro watts for this constraint.
 128                 Here "X" can have values from 0 to max integer.
 129
 130 What:           /sys/class/powercap/.../<power zone>/constraint_X_max_time_window_us
 131 Date:           September 2013
 132 KernelVersion:  3.13
 133 Contact:        linux-pm@vger.kernel.org
 134 Description:
 135                 Maximum allowed time window in micro seconds for this
 136                 constraint. Here "X" can have values from 0 to max integer.
 137
 138 What:           /sys/class/powercap/.../<power zone>/constraint_X_min_time_window_us
 139 Date:           September 2013
 140 KernelVersion:  3.13
 141 Contact:        linux-pm@vger.kernel.org
 142 Description:
 143                 Minimum allowed time window in micro seconds for this
 144                 constraint. Here "X" can have values from 0 to max integer.
 145
 146 What:           /sys/class/powercap/.../<power zone>/enabled
 147 Date:           September 2013
 148 KernelVersion:  3.13
 149 Contact:        linux-pm@vger.kernel.org
 150 Description
 151                 This allows to enable/disable power capping at power zone level.
 152                 This applies to current power zone and its children.