Each APU core includes a virtual counter that indicates virtual time. The virtual counter contains the value of the physical counter minus a 64-bit virtual offset. When executing in a non-secure EL1 or EL0 mode, the virtual offset value relates to the current virtual machine.
The CNTVOFF register contains the virtual offset. CNTVOFF is only accessible from EL2 or EL3 when SCR.NS is set to 1. The CNTVCT register holds the current virtual counter value.