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+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
+
+Author: Andreas Herrmann <herrmann.der.user@googlemail.com>
+
+Description
+-----------
+
+1) Processor TDP (Thermal design power)
+
+Given a fixed frequency and voltage, the power consumption of a
+processor varies based on the workload being executed. Derated power
+is the power consumed when running a specific application. Thermal
+design power (TDP) is an example of derated power.
+
+This driver permits reading of registers providing power information
+of AMD Family 15h and 16h processors via TDP algorithm.
+
+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
+    consumed by the processor for NB and logic external to the core.
+
+* ProcessorPwrWatts:
+    Specifies in watts the maximum amount of power
+    the processor can support.
+* 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)
+
+On multi-node processors the calculated value is for the entire
+package and not for a single node. Thus the driver creates sysfs
+attributes only for internal node0 of a multi-node processor.
+
+2) Accumulated Power Mechanism
+
+This driver also introduces an algorithm that should be used to
+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
+	PTSC period
+
+* Jmax:
+	max compute unit accumulated power which is indicated by
+	MaxCpuSwPwrAcc MSR C001007b
+
+* Jx/Jy:
+	compute unit accumulated power which is indicated by
+	CpuSwPwrAcc MSR C001007a
+* Tx/Ty:
+	the value of performance timestamp counter which is indicated
+	by CU_PTSC MSR C0010280
+
+* 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.
+
+iv. At time y, SW reads CpuSwPwrAcc MSR and samples the 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::
+
+	if (Jy < Jx) // Rollover has occurred
+		Jdelta = (Jy + Jmax) - Jx
+	else
+		Jdelta = Jy - Jx
+	PwrCPUave = N * Jdelta * 1000 / (Ty - Tx)
+
+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-*`
+	set power1_average_interval 0.01
+
+Then save it with "sensors -s".