The CNTVOFF characteristics are:
Holds the 64-bit virtual offset for a CNTBaseN frame that has virtual timer capability. This is the offset between real time and virtual time.
This register is part of the Generic Timer registers functional group.
This register is accessible as follows:
Default |
---|
RO |
In the CNTCTLBase frame a CNTVOFF<n> register must be implemented, as a RW register, for each CNTBaseN frame that has virtual timer capability.
The value of <n> in an instance of CNTVOFF<n> specifies the value of N for the associated CNTBaseN frame.
In a system that recognizes two Security states, for any CNTVOFF<n> register in the CNTCTLBase frame:
The register location of any unimplemented CNTVOFF<n> register in the CNTCTLBase frame is RAZ/WI.
CNTVOFF is implemented, as a RO register, in any implemented CNTBaseN frame that has virtual timer capability.
'CNTCTLBase status and control fields for the CNTBaseN and CNTEL0BaseN frames' in Chapter I1 of the ARMv8 ARM describes the status fields that identify whether a CNTBaseN frame is implemented, and for an implemented frame:
For an implemented CNTBaseN frame that has virtual timer capability:
CNTVOFF is never visible in any CNTEL0BaseN frame. This means that the CNTVOFF address in any implemented CNTEL0BaseN frame is RAZ/WI.
In an implementation that supports 64-bit atomic accesses, a CNTVOFF{<n>} register must be accessible as an atomic 64-bit value.
The power domain of CNTVOFF 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.
CNTVOFF is a 64-bit register.
The CNTVOFF bit assignments are:
63 | 62 | 61 | 60 | 59 | 58 | 57 | 56 | 55 | 54 | 53 | 52 | 51 | 50 | 49 | 48 | 47 | 46 | 45 | 44 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32 |
Virtual offset | |||||||||||||||||||||||||||||||
Virtual offset | |||||||||||||||||||||||||||||||
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
Virtual offset.
CNTVOFF[31:0] can be accessed through its memory-mapped interface:
Component | Frame | Offset |
---|---|---|
Timer | CNTBaseN | 0x018 |
CNTVOFF[63:32] can be accessed through its memory-mapped interface:
Component | Frame | Offset |
---|---|---|
Timer | CNTBaseN | 0x01C |
18/04/2017 17:00
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