CNTCV, Counter Count Value register

The CNTCV characteristics are:

Purpose

Indicates the current count value.

This register is part of the Generic Timer registers functional group.

Usage constraints

This register is accessible as follows:

Default
RW in CNTControlBase, RO in CNTReadBase
Frame Accessibility
CNTControlBase RW
CNTReadBase RO

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

Configuration

The power domain of CNTCV is IMPLEMENTATION DEFINED.

On a reset of the reset domain in which an RW instance of this register is implemented, RW fields in the register reset to UNKNOWN values. The register is not affected by a reset of any other reset domain. For more information see 'Power and reset domains for the system level implementation of the Generic Timer' in Chapter I1 of the ARMv8 ARM.

Attributes

CNTCV is a 64-bit register.

Field descriptions

The CNTCV bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
CountValue
CountValue
313029282726252423222120191817161514131211109876543210

CountValue, bits [63:0]

Indicates the counter value.

Accessing the CNTCV

CNTCV[31:0] can be accessed through its memory-mapped interface:

ComponentFrameOffset
TimerCNTControlBase 0x008
TimerCNTReadBase 0x000

CNTCV[63:32] can be accessed through its memory-mapped interface:

ComponentFrameOffset
TimerCNTControlBase 0x00C
TimerCNTReadBase 0x004



28/09/2017 08:24

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