OPAL_IMC_COUNTERS_INIT

OPAL call interface to initialize In-memory collection infrastructure. Call does multiple scom writes on each invocation for Core/Trace IMC initialization. And for the Nest IMC, at this point, call is a no-op and returns OPAL_SUCCESS. Incase of kexec, OS driver should first stop the engine via OPAL_IMC_COUNTER_STOP(and then free the memory if allocated, for nest memory is mmapped). Incase of kdump, OS driver should stop the engine via OPAL_IMC_COUNTER_STOP.

OPAL does sanity checks to detect unknown or unsupported IMC device type and nest units. check_imc_device_type() function removes unsupported IMC device type. disable_unavailable_units() removes unsupported nest units by the microcode. This way OPAL can lock down and advertise only supported device type and nest units.

Parameters

uint32_t type
This parameter specifies the imc counter domain. The value can be ‘OPAL_IMC_COUNTERS_NEST’, ‘OPAL_IMC_COUNTERS_CORE’ or ‘OPAL_IMC_COUNTERS_TRACE’.
uint64_t addr
This parameter must have a non-zero value. This value must be a physical address of the core.
uint64_t cpu_pir
This parameter specifices target cpu pir

Returns

OPAL_PARAMETER
In case of unsupported type
OPAL_HARDWARE
If any error in setting up the hardware.
OPAL_SUCCESS
On succesfully initialized or even if init operation is a no-op.

OPAL_IMC_COUNTERS_START

OPAL call interface for starting the In-Memory Collection counters for a specified domain (NEST/CORE/TRACE).

Parameters

uint32_t type
This parameter specifies the imc counter domain. The value can be ‘OPAL_IMC_COUNTERS_NEST’, ‘OPAL_IMC_COUNTERS_CORE’ or ‘OPAL_IMC_COUNTERS_TRACE’.
uint64_t cpu_pir
This parameter specifices target cpu pir

Returns

OPAL_PARAMETER
In case of Unsupported type
OPAL_HARDWARE
If any error in setting up the hardware.
OPAL_SUCCESS
On successful execution of the operation for the given type.

OPAL_IMC_COUNTERS_STOP

OPAL call interface for stoping In-Memory Collection counters for a specified domain (NEST/CORE/TRACE). STOP should always be called after a related START. While STOP may run successfully without an associated START call, this is not gaurenteed.

Parameters

uint32_t type
This parameter specifies the imc counter domain. The value can be ‘OPAL_IMC_COUNTERS_NEST’, ‘OPAL_IMC_COUNTERS_CORE’ or ‘OPAL_IMC_COUNTERS_TRACE’
uint64_t cpu_pir
This parameter specifices target cpu pir

Returns

OPAL_PARAMETER
In case of Unsupported type
OPAL_HARDWARE
If any error in setting up the hardware.
OPAL_SUCCESS
On successful execution of the operation for the given type.