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author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-06 19:56:51 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-06 19:56:51 -0700 |
commit | 7aefd944f038c7469571adb37769cb6f3924ecfa (patch) | |
tree | f0a8dc23633b6bbbc4f0bff932f332e847fb6c1b /Documentation/hwmon/fam15h_power.rst | |
parent | Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip (diff) | |
parent | hwmon: (lm75) Add support for TMP75B (diff) | |
download | linux-dev-7aefd944f038c7469571adb37769cb6f3924ecfa.tar.xz linux-dev-7aefd944f038c7469571adb37769cb6f3924ecfa.zip |
Merge tag 'hwmon-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon updates from Guenter Roeck:
- Add driver for Intersil ISL68137 PWM Controller
- Add driver for Lochnagar 2
- Add driver for Infineon IR38064 Voltage Regulator
- Add support for TMP75B to lm75 driver
- Convert documentation to ReST format
- Use request_muxed_region for Super-IO accesses in several drivers
- Add 'samples' attribute to ABI, and start using it
- Add support for custom sysfs attributes to pmbus drivers (used in
ISL68137 driver)
- Introduce HWMON_CHANNEL_INFO macro
- Automated changes:
- Use permission specific [SENSOR_][DEVICE_]ATTR variants
- Fix build warnings due to unused of_device_id structures
- Use HWMON_CHANNEL_INFO macro
- Various minor improvements and fixes
* tag 'hwmon-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: (125 commits)
hwmon: (lm75) Add support for TMP75B
dt-bindings: hwmon: Add tmp75b to lm75.txt
hwmon: (s3c) Use dev_get_drvdata()
hwmon: (max6650) Drop call to thermal_cdev_update
docs: hwmon: remove the extension from .rst files
docs: hwmon: convert three docs to ReST format
hwmon: (max6650) add thermal cooling device capability
hwmon: (ina3221) Add voltage conversion time settings
hwmon: (ina3221) Do not read-back to cache reg_config
docs: hwmon: Add an index file and rename docs to *.rst
docs: hwmon: convert remaining files to ReST format
docs: hwmon: misc files: convert to ReST format
docs: hwmon: pmbus files: convert to ReST format
docs: hwmon: k8temp, w83793: convert to ReST format
docs: hwmon: da9052, da9055: convert to ReST format
docs: hwmon: wm831x, wm8350: convert to ReST format
docs: hwmon: dme1737, vt1211: convert to ReST format
docs: hwmon: ads1015: convert to ReST format
docs: hwmon: asc7621: convert to ReST format
docs: hwmon: ibmpowernv: convert to ReST format
...
Diffstat (limited to 'Documentation/hwmon/fam15h_power.rst')
-rw-r--r-- | Documentation/hwmon/fam15h_power.rst | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/Documentation/hwmon/fam15h_power.rst b/Documentation/hwmon/fam15h_power.rst new file mode 100644 index 000000000000..fdde632c93a3 --- /dev/null +++ b/Documentation/hwmon/fam15h_power.rst @@ -0,0 +1,131 @@ +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". |