CNTFID0, Counter Frequency ID

The CNTFID0 characteristics are:

Purpose

Indicates the base frequency of the system counter.

Configuration

The power domain of CNTFID0 is IMPLEMENTATION DEFINED.

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

The possible frequencies for the system counter are stored in the Frequency modes table as 32-bit words starting with the base frequency, CNTFID0. For more information, see 'The Frequency modes table'.

The final entry in the Frequency modes table must be followed by a 32-bit word of zero value, to mark the end of the table.

Typically, the Frequency modes table will be in read-only memory. However, a system implementation might use read/write memory for the table, and initialize the table entries as part of its start-up sequence.

If the Frequency modes table is in read/write memory, Arm strongly recommends that the table is not updated once the system is running.

Attributes

CNTFID0 is a 32-bit register.

Field descriptions

313029282726252423222120191817161514131211109876543210
Frequency

Frequency, bits [31:0]

The base frequency of the system counter, in Hz.

The reset behavior of this field is:

Accessing CNTFID0

It is IMPLEMENTATION DEFINED whether this register is RO or RW

In a system that supports Secure and Non-secure memory maps the CNTControlBase frame, that includes this register, is implemented only in the Secure memory map.

CNTFID0 can be accessed through the memory-mapped interfaces:

ComponentFrameOffsetInstance
TimerCNTControlBase0x020CNTFID0

Accesses to this interface are RO or RW.


05/07/2022 17:07; b0421fa9a8865165f9b91af9b4a566111f866305

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