Commit b413e3fa authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab Committed by Guenter Roeck
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docs: hwmon: fam15h_power: convert to ReST format 



Convert fam15h_power to ReST format, in order to allow it to
be parsed by Sphinx.

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent a9fc881b

Documentation/hwmon/fam15h_power

+57 −28
Original line number Diff line number Diff line
@@ -2,15 +2,20 @@ Kernel driver fam15h_power 
==========================



Supported chips:



* AMD Family 15h Processors



* AMD Family 16h Processors



  Prefix: 'fam15h_power'



  Addresses scanned: PCI space



  Datasheets:

  BIOS and Kernel Developer's Guide (BKDG) For AMD Family 15h Processors

  BIOS and Kernel Developer's Guide (BKDG) For AMD Family 16h Processors

  AMD64 Architecture Programmer's Manual Volume 2: System Programming



  - BIOS and Kernel Developer's Guide (BKDG) For AMD Family 15h Processors

  - BIOS and Kernel Developer's Guide (BKDG) For AMD Family 16h Processors

  - AMD64 Architecture Programmer's Manual Volume 2: System Programming



Author: Andreas Herrmann <herrmann.der.user@googlemail.com>
@@ -31,14 +36,19 @@ For AMD Family 15h and 16h processors the following power values can 
be calculated using different processor northbridge function

registers:



* BasePwrWatts: Specifies in watts the maximum amount of power

* BasePwrWatts:

    Specifies in watts the maximum amount of power

    consumed by the processor for NB and logic external to the core.

* ProcessorPwrWatts: Specifies in watts the maximum amount of power



* ProcessorPwrWatts:

    Specifies in watts the maximum amount of power

    the processor can support.

* CurrPwrWatts: Specifies in watts the current amount of power being

* CurrPwrWatts:

    Specifies in watts the current amount of power being

    consumed by the processor.



This driver provides ProcessorPwrWatts and CurrPwrWatts:



* power1_crit (ProcessorPwrWatts)

* power1_input (CurrPwrWatts)
@@ -53,35 +63,53 @@ calculate the average power consumed by a processor during a 
measurement interval Tm. The feature of accumulated power mechanism is

indicated by CPUID Fn8000_0007_EDX[12].



* Tsample: compute unit power accumulator sample period

* Tref: the PTSC counter period

* PTSC: performance timestamp counter

* N: the ratio of compute unit power accumulator sample period to the

* Tsample:

	compute unit power accumulator sample period



* Tref:

	the PTSC counter period



* PTSC:

	performance timestamp counter



* N:

	the ratio of compute unit power accumulator sample period to the

	PTSC period

* Jmax: max compute unit accumulated power which is indicated by



* Jmax:

	max compute unit accumulated power which is indicated by

	MaxCpuSwPwrAcc MSR C001007b

* Jx/Jy: compute unit accumulated power which is indicated by



* Jx/Jy:

	compute unit accumulated power which is indicated by

	CpuSwPwrAcc MSR C001007a

* Tx/Ty: the value of performance timestamp counter which is indicated

* Tx/Ty:

	the value of performance timestamp counter which is indicated

	by CU_PTSC MSR C0010280

* PwrCPUave: CPU average power



* PwrCPUave:

	CPU average power



i. Determine the ratio of Tsample to Tref by executing CPUID Fn8000_0007.



	N = value of CPUID Fn8000_0007_ECX[CpuPwrSampleTimeRatio[15:0]].



ii. Read the full range of the cumulative energy value from the new

    MSR MaxCpuSwPwrAcc.



	Jmax = value returned.



iii. At time x, SW reads CpuSwPwrAcc MSR and samples the PTSC.

	Jx = value read from CpuSwPwrAcc and Tx = value read from

PTSC.



	Jx = value read from CpuSwPwrAcc and Tx = value read from PTSC.



iv. At time y, SW reads CpuSwPwrAcc MSR and samples the PTSC.

	Jy = value read from CpuSwPwrAcc and Ty = value read from

PTSC.



	Jy = value read from CpuSwPwrAcc and Ty = value read from PTSC.



v. Calculate the average power consumption for a compute unit over

time period (y-x). Unit of result is uWatt.

   time period (y-x). Unit of result is uWatt::



	if (Jy < Jx) // Rollover has occurred

		Jdelta = (Jy + Jmax) - Jx

	else
@@ -90,13 +118,14 @@ time period (y-x). Unit of result is uWatt. 


This driver provides PwrCPUave and interval(default is 10 millisecond

and maximum is 1 second):



* power1_average (PwrCPUave)

* power1_average_interval (Interval)



The power1_average_interval can be updated at /etc/sensors3.conf file

as below:



chip "fam15h_power-*"

chip `fam15h_power-*`

	set power1_average_interval 0.01



Then save it with "sensors -s".