CNTV_CVAL, Counter-timer Virtual Timer CompareValue

The CNTV_CVAL characteristics are:

Purpose

Holds the 64-bit compare value for the virtual timer.

Configuration

The power domain of CNTV_CVAL is IMPLEMENTATION DEFINED.

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

Attributes

CNTV_CVAL is a 64-bit register.

Field descriptions

The CNTV_CVAL bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
CompareValue
CompareValue
313029282726252423222120191817161514131211109876543210

CompareValue, bits [63:0]

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.

Accessing the CNTV_CVAL

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' 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.

CNTV_CVAL can be accessed through the memory-mapped interfaces:

ComponentFrameOffsetInstanceRange
TimerCNTBaseN0x030CNTV_CVAL31:0

Accesses on this interface are RW.

ComponentFrameOffsetInstanceRange
TimerCNTBaseN0x034CNTV_CVAL63:32

Accesses on this interface are RW.

ComponentFrameOffsetInstanceRange
TimerCNTEL0BaseN0x030CNTV_CVAL31:0

Accesses on this interface are RW.

ComponentFrameOffsetInstanceRange
TimerCNTEL0BaseN0x034CNTV_CVAL63:32

Accesses on this interface are RW.




01/07/2020 15:57; 80324f0b9997bede489cc15ad1565345720bcd2a

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