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CNTID, Counter Identification Register

The CNTID characteristics are:

Purpose

Indicates whether counter scaling is implemented.

Configuration

It is IMPLEMENTATION DEFINED whether CNTID is implemented in the Core power domain or in the Debug power domain.

This register is present only when FEAT_CNTSC is implemented. Otherwise, direct accesses to CNTID are RES0.

Attributes

CNTID is a 32-bit register.

Field descriptions

Bits [31:4]

CNTSC, bits [3:0]

Accessing CNTID

In a system that supports the Realm Management Extension, the CNTControlBase frame, which includes this register, is implemented only in the Root physical address space.

In a system that supports Secure and Non-secure physical address spaces, the CNTControlBase frame, which includes this register, is implemented only in the Secure physical address space.

CNTID can be accessed through the memory-mapped interfaces:

Accesses to this register are RO.

2026-03-12 12:23:09, 2025-09_rel_asl1

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