POWER On-Chip Controller Driver Coming For Linux 4.21
The on-chip controller is embedded into POWER processors with P8/P9 processors. The newly-queued OCC driver exposes via sysfs temperatures, frequencies, power usage, power capacity/minimum/maximums, and other sensor data. The OCC driver documentation covers the information in more detail.
The POWER OCC code is currently queued in hwmon-next for introduction in the next cycle that will be Linux 4.21 unless Linus Torvalds decides to rename that next kernel release to Linux 5.0.