The CNTV_CVAL characteristics are:
Holds the 64-bit compare value for the virtual timer.
The power domain of CNTV_CVAL 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 Arm® Architecture Reference Manual, Armv8, for Armv8-A architecture profile.
CNTV_CVAL is a 64-bit register.
The CNTV_CVAL 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 |
CompareValue | |||||||||||||||||||||||||||||||
CompareValue | |||||||||||||||||||||||||||||||
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 |
Holds the virtual timer CompareValue.
When CNTV_CTL.ENABLE is 1, the timer condition is met when (CNTVCT - CompareValue) is greater than or equal to zero. This means that CompareValue acts like a 64-bit upcounter timer. When the timer condition is met:
When CNTV_CTL.ENABLE is 0, the timer condition is not met, but CNTVCT continues to count.
This field resets to an architecturally UNKNOWN value.
CNTV_CVAL can be implemented in any implemented CNTBaseN frame that has virtual timer capability, and in the corresponding CNTEL0BaseN frame.
'CNTCTLBase status and control fields for the CNTBaseN and CNTEL0BaseN frames' in Chapter I1 of the Arm® Architecture Reference Manual, Armv8, for Armv8-A architecture profile 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:
For an implemented CNTEL0BaseN frame:
If the implementation supports 64-bit atomic accesses, then the CNTV_CVAL register must be accessible as an atomic 64-bit value.
Component | Frame | Offset | Instance | Range |
---|---|---|---|---|
Timer | CNTBaseN | 0x030 | CNTV_CVAL | 31:0 |
Access on this interface is RW.
Component | Frame | Offset | Instance | Range |
---|---|---|---|---|
Timer | CNTBaseN | 0x034 | CNTV_CVAL | 63:32 |
Access on this interface is RW.
Component | Frame | Offset | Instance | Range |
---|---|---|---|---|
Timer | CNTEL0BaseN | 0x030 | CNTV_CVAL | 31:0 |
Access on this interface is RW.
Component | Frame | Offset | Instance | Range |
---|---|---|---|---|
Timer | CNTEL0BaseN | 0x034 | CNTV_CVAL | 63:32 |
Access on this interface is RW.
27/03/2019 21:59; e5e4db499bf9867a4b93324c4dbac985d3da9376
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