CNTCV, Counter Count Value register

The CNTCV characteristics are:

Purpose

Indicates the current count value.

Configuration

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

For more information, see 'Power and reset domains for the system level implementation of the Generic Timer'.

Attributes

CNTCV is a 64-bit register.

Field descriptions

CountValue, bits [63:0]

Accessing CNTCV

A write to CNTCV must be visible in the CNTPCT register of each running processor in a finite time.

For the instance of the register in the CNTControlBase frame:

• In a system that supports the Realm Management Extension, this register is implemented only in the Root physical address space.
• In a system that supports Secure and Non-secure physical address spaces, this register is implemented only in the Secure physical address space.
• If the counter is enabled, the effect of writing to the register is UNKNOWN.

For the instance of the register in the CNTReadBase frame, this register is accessible in all physical address spaces.

In an implementation that supports 64-bit atomic memory accesses, this register must be accessible using a 64-bit atomic access.

CNTCV can be accessed through the memory-mapped interfaces:

Accesses to this register are RW.

Accesses to this register are RO.

21/03/2025 17:53; 154105dd5041532b480d9ef0c018b8420cbe5c19

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