11.7.5. Performance Monitors Snapshot Status Register

The PMSSR characteristics are:

Purpose

Provides status information on whether the PMU counters have been captured.

Usage constraints

The external accessibility to the PMSSR by condition code is:

OffDLKOSLKEPMADSLKDefault
ErrorErrorRORORORO

Table 11.1 describes the condition codes.

A security violation prevents the capture of the event counters.

The external monitor must keep track of whether the snapshot registers were captured by the processor.

To prevent loss of data, software must save and restore the PMU state, including the PMSCR and PMSRR registers, when capturing over a reset or power down.

Configurations

There is no configuration information for PMSSR.

Attributes

See the register summary in Table 11.7.

Figure 11.5 shows the PMSSR bit assignments.

Figure 11.5. PMSSR bit assignments

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Table 11.9 shows the PMSSR bit assignments.

Table 11.9. PMSSR bit assignments

BitsNameFunction
[31:1]-Reserved, res0.
[0]NC

No capture. The possible values are:

0

PMU counters captured.

1

PMU counters not captured.

The NC bit:

  • Is reset to 1 by a Warm reset but overwritten at the first capture.

  • Does not reflect the status of the captured Program Counter Sample registers.


PMSSR can be accessed through the internal memory-mapped interface and the external debug interface, offset 0x610.

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