Visible to Intel only — GUID: pxg1685725291528
Ixiasoft
Visible to Intel only — GUID: pxg1685725291528
Ixiasoft
3.1.8. 1214720: VFP_SPEC PMU event might count incorrectly
Description
The Cortex-A55 core implements several architectural and IMPLEMENTATION DEFINED performance monitor events. Because of this erratum, the VFP_SPEC event might not count correctly.
Conditions
One of the PMU event counters is configured to count the 0x075, VFP_SPEC event.
Impact
The PMU counts SIMD floating-point instructions as well as scalar floating-point instructions.
Workaround
In some situations, where integer SIMD instructions are known not to be used, the ASE_SPEC count can be subtracted from the VFP_SPEC count to give the number of scalar VFP instructions.
Category
Category C