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power-management.rst
changeset 2228 837f1337c59b
parent 1912 8b81a8f0f692 
--- a/power-management.rst	Sat Feb 10 01:28:53 2018 +0200
+++ b/power-management.rst	Sat Feb 10 01:30:24 2018 +0200
@@ -6,88 +6,91 @@
 .. contents::
    :local:
 
-* ACPI power states.
+ACPI power states
+=================
 
-  http://en.wikipedia.org/wiki/Advanced_Configuration_and_Power_Interface
+* http://en.wikipedia.org/wiki/Advanced_Configuration_and_Power_Interface
 
-** Global states.
+Global states:
 
- * G0 (S0) Working
- * G1 Sleeping (subdivides into the four states S1 through S4)
+* G0 (S0) Working
+* G1 Sleeping (subdivides into the four states S1 through S4)
 
-   * S1: All processor caches are flushed, and the CPU(s) stop executing
-     instructions. Power to the CPU(s) and RAM is maintained; devices that do
-     not indicate they must remain on may be powered down.
-   * S2: CPU powered off.
-   * S3: Commonly referred to as Standby, Sleep, or Suspend to RAM. RAM
-     remains powered.
-   * S4: Hibernation or Suspend to Disk. All content of main memory is saved
-     to non-volatile memory such as a hard drive, and is powered down.
- * G2 (S5) Soft Off. G2, S5, and Soft Off are synonyms. G2 is almost the same
-   as G3 Mechanical Off, but some components remain powered so the computer
-   can "wake" from input from the keyboard, clock, modem, LAN, or USB device.
- * G3 Mechanical Off: The computer's power consumption approaches close to
-   zero, to the point that the power cord can be removed and the system is
-   safe for dis-assembly (typically, only the real-time clock is running off
-   its own small battery).
+  * S1: All processor caches are flushed, and the CPU(s) stop executing
+    instructions. Power to the CPU(s) and RAM is maintained; devices that do
+    not indicate they must remain on may be powered down.
+  * S2: CPU powered off.
+  * S3: Commonly referred to as Standby, Sleep, or Suspend to RAM. RAM
+    remains powered.
+  * S4: Hibernation or Suspend to Disk. All content of main memory is saved
+    to non-volatile memory such as a hard drive, and is powered down.
+* G2 (S5) Soft Off. G2, S5, and Soft Off are synonyms. G2 is almost the same
+  as G3 Mechanical Off, but some components remain powered so the computer
+  can "wake" from input from the keyboard, clock, modem, LAN, or USB device.
+* G3 Mechanical Off: The computer's power consumption approaches close to
+  zero, to the point that the power cord can be removed and the system is
+  safe for dis-assembly (typically, only the real-time clock is running off
+  its own small battery).
 
-** System states.
+System states:
 
- * S0 Working (G0), Processor in C0-C3, full context save RAM maintained
- * S1 Sleeping with processor context maintained, RAM maintained
- * S2 Sleeping with processor content not necessarily maintained, RAM
-   maintained, most devices in D3
- * S3 Sleeping, lower than S2, RAM maintained, most devices in D3
- * S4 Sleeping, lower than S3, RAM not maintained, most devices in D3
- * S5 Sleeping, lower than S4, no context saved, reboot necessary
+* S0 Working (G0), Processor in C0-C3, full context save RAM maintained
+* S1 Sleeping with processor context maintained, RAM maintained
+* S2 Sleeping with processor content not necessarily maintained, RAM
+  maintained, most devices in D3
+* S3 Sleeping, lower than S2, RAM maintained, most devices in D3
+* S4 Sleeping, lower than S3, RAM not maintained, most devices in D3
+* S5 Sleeping, lower than S4, no context saved, reboot necessary
 
-** Device states.
+Device states:
 
- * D0 Fully-On is the operating state.
- * D1 and D2 are intermediate power-states whose definition varies by device.
- * D3 Off has the device powered off and unresponsive to its bus.
+* D0 Fully-On is the operating state.
+* D1 and D2 are intermediate power-states whose definition varies by device.
+* D3 Off has the device powered off and unresponsive to its bus.
 
-** Processor states.
+Processor states:
 
- * C0 is the operating state.
- * C1 (often known as Halt) is a state where the processor is not executing
-   instructions, but can return to an executing state essentially
-   instantaneously. All ACPI-conformant processors must support this power state.
- * C2 (often known as Stop-Clock) is a state where the processor maintains all
-   software-visible state, but may take longer to wake up. This processor
-   state is optional.
- * C3 (often known as Sleep) is a state where the processor does not need to
-   keep its cache coherent, but maintains other state. Some processors have
-   variations on the C3 state (Deep Sleep, Deeper Sleep, etc.) that differ in
-   how long it takes to wake the processor. This processor state is optional.
+* C0 is the operating state.
+* C1 (often known as Halt) is a state where the processor is not executing
+  instructions, but can return to an executing state essentially
+  instantaneously. All ACPI-conformant processors must support this power state.
+* C2 (often known as Stop-Clock) is a state where the processor maintains all
+  software-visible state, but may take longer to wake up. This processor
+  state is optional.
+* C3 (often known as Sleep) is a state where the processor does not need to
+  keep its cache coherent, but maintains other state. Some processors have
+  variations on the C3 state (Deep Sleep, Deeper Sleep, etc.) that differ in
+  how long it takes to wake the processor. This processor state is optional.
 
-** Performance states.
+Performance states:
 
- * P0 max power and frequency.
- * P1 less than P0, voltage/frequency scaled.
- * Pn less than P(n-1), voltage/frequency scaled.
+* P0 max power and frequency.
+* P1 less than P0, voltage/frequency scaled.
+* Pn less than P(n-1), voltage/frequency scaled.
 
-* Control power schema under Windows.
+Control power schema under Windows
+==================================
 
-Use powercfg utility. To se current state:
+Use ``powercfg`` utility. To se current state::
 
   cmd> powercfg /QUERY
 
-To see all available states:
+To see all available states::
 
   cmd> powercfg /LIST
 
-To restore power configurtion:
+To restore power configurtion::
 
   cmd> powercfg /RestoreDefaultPolicies
 
-* Intel.
+Intel
+=====
 
-** Intel Speedstep® Technology.
+Intel Speedstep® Technology:
 
-  http://www.intel.com/support/processors/sb/CS-028855.htm
-                Frequently asked questions for Intel Speedstep® Technology
-  http://www.intel.com/p/en_US/support/highlights/processors/frequencyid
-                Intel® Processor Frequency ID Utility
-  http://software.intel.com/en-us/articles/enhanced-intel-speedstepr-technology-and-demand-based-switching-on-linux
-                Enhanced Intel SpeedStep® Technology and Demand-Based Switching on Linux
+http://www.intel.com/support/processors/sb/CS-028855.htm
+  Frequently asked questions for Intel Speedstep® Technology
+http://www.intel.com/p/en_US/support/highlights/processors/frequencyid
+  Intel® Processor Frequency ID Utility
+http://software.intel.com/en-us/articles/enhanced-intel-speedstepr-technology-and-demand-based-switching-on-linux
+  Enhanced Intel SpeedStep® Technology and Demand-Based Switching on Linux
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