Description¶

This driver supports hardware monitoring for the On-Chip Controller (OCC)embedded on POWER processors. The OCC is a device that collects and aggregatessensor data from the processor and the system. The OCC can provide the rawsensor data as well as perform thermal and power management on the system.

The P8 version of this driver is a client driver of I2C. It may be probedmanually if an “ibm,p8-occ-hwmon” compatible device is found under theappropriate I2C bus node in the device-tree.

The P9 version of this driver is a client driver of the FSI-based OCC driver.It will be probed automatically by the FSI-based OCC driver.

Sysfs entries¶

The following attributes are supported. All attributes are read-only unlessspecified.

The OCC sensor ID is an integer that represents the unique identifier of thesensor with respect to the OCC. For example, a temperature sensor for the thirdDIMM slot in the system may have a sensor ID of 7. This mapping is unavailableto the device driver, which must therefore export the sensor ID as-is.

Some entries are only present with certain OCC sensor versions or only oncertain OCCs in the system. The version number is not exported to the userbut can be inferred.

temp[1-n]_label

OCC sensor ID.

[with temperature sensor version 1]

temp[1-n]_input

Measured temperature of the component in millidegreesCelsius.

[with temperature sensor version >= 2]

temp[1-n]_type

The FRU (Field Replaceable Unit) type(represented by an integer) for the componentthat this sensor measures.

temp[1-n]_fault

Temperature sensor fault boolean; 1 to indicatethat a fault is present or 0 to indicate thatno fault is present.

[with type == 3 (FRU type is VRM)]

temp[1-n]_alarm

VRM temperature alarm boolean; 1 to indicatealarm, 0 to indicate no alarm

[else]

temp[1-n]_input

Measured temperature of the component inmillidegrees Celsius.

freq[1-n]_label

OCC sensor ID.

freq[1-n]_input

Measured frequency of the component in MHz.

power[1-n]_input

Latest measured power reading of the component inmicrowatts.

power[1-n]_average

Average power of the component in microwatts.

power[1-n]_average_interval

The amount of time over which the power averagewas taken in microseconds.

[with power sensor version < 2]

power[1-n]_label

OCC sensor ID.

[with power sensor version >= 2]

power[1-n]_label

OCC sensor ID + function ID + channel in the formof a string, delimited by underscores, i.e. “0_15_1”.Both the function ID and channel are integers thatfurther identify the power sensor.

[with power sensor version 0xa0]

power[1-n]_label

OCC sensor ID + sensor type in the form of a string,delimited by an underscore, i.e. “0_system”. Sensortype will be one of “system”, “proc”, “vdd” or “vdn”.For this sensor version, OCC sensor ID will be the samefor all power sensors.

[present only on “master” OCC; represents the whole system power; only one ofthis type of power sensor will be present]

power[1-n]_label

“system”

power[1-n]_input

Latest system output power in microwatts.

power[1-n]_cap

Current system power cap in microwatts.

power[1-n]_cap_not_redundant

System power cap in microwatts whenthere is not redundant power.

power[1-n]_cap_max

Maximum power cap that the OCC can enforce inmicrowatts.

power[1-n]_cap_min Minimum power cap that the OCC can enforce in

microwatts.

power[1-n]_cap_user The power cap set by the user, in microwatts.

This attribute will return 0 if no user powercap has been set. This attribute is read-write,but writing any precision below watts will beignored, i.e. requesting a power cap of500900000 microwatts will result in a power caprequest of 500 watts.

[with caps sensor version > 1]

power[1-n]_cap_user_source

Indicates how the user power cap wasset. This is an integer that maps tosystem or firmware components that canset the user power cap.

The following “extn” sensors are exported as a way for the OCC to provide datathat doesn’t fit anywhere else. The meaning of these sensors is entirelydependent on their data, and cannot be statically defined.

extn[1-n]_label

ASCII ID or OCC sensor ID.

extn[1-n]_flags

This is one byte hexadecimal value. Bit 7 indicates thetype of the label attribute; 1 for sensor ID, 0 forASCII ID. Other bits are reserved.

extn[1-n]_input

6 bytes of hexadecimal data, with a meaning defined bythe sensor ID.