CNTVOFF<n>, Counter-timer Virtual Offsets, n = 0 - 7

The CNTVOFF<n> characteristics are:

Purpose

Holds the 64-bit virtual offset for frame CNTBase<n>. This is the offset between real time and virtual time.

Configuration

The power domain of CNTVOFF<n> is IMPLEMENTATION DEFINED.

Implementation of this register is OPTIONAL.

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

Attributes

CNTVOFF<n> is a 64-bit register.

Field descriptions

The CNTVOFF<n> bit assignments are:

Bits [63:0]

Virtual offset.

On a Warm reset, this field resets to an architecturally UNKNOWN value.

Accessing the CNTVOFF<n>

In the CNTCTLBase frame a CNTVOFF<n> register must be implemented, as a RW register, for each CNTBaseN frame that has virtual timer capability. For more information, see 'CNTCTLBase status and control fields for the CNTBaseN and CNTEL0BaseN frames'.

In a system that recognizes two Security states, for any CNTVOFF<n> register in the CNTCTLBase frame:

• CNTVOFF<n> is always accessible by Secure accesses.
• CNTNSAR.NS<n> determines whether CNTVOFF<n> is accessible by Non-secure accesses.

The register location of any unimplemented CNTVOFF<n> register in the CNTCTLBase frame is RAZ/WI.

The CNTVOFF<n> register is accessible in the CNTBaseN frame using CNTVOFF.

In an implementation that supports 64-bit atomic accesses, then the CNTVOFF<n> registers must be accessible as atomic 64-bit values.

CNTVOFF<n> can be accessed through the memory-mapped interfaces:

Accesses on this interface are RW.

Accesses on this interface are RW.