CTILAR, CTI Lock Access Register

The CTILAR characteristics are:

Purpose

Allows or disallows access to the CTI registers through a memory-mapped interface.

This register is part of the Cross-Trigger Interface registers functional group.

Usage constraints

This register is accessible as follows:

Default
WO

Configuration

CTILAR is in the Debug power domain.

If OPTIONAL memory-mapped access to the external debug interface is supported then an OPTIONAL Software Lock can be implemented as part of CoreSight compliance.

CTILAR ignores writes if the Software lock is not implemented and ignores writes for other accesses to the external debug interface.

The Software Lock provides a lock to prevent memory-mapped writes to the Cross-Trigger Interface registers. Use of this lock mechanism reduces the risk of accidental damage to the contents of the Cross-Trigger Interface registers. It does not, and cannot, prevent all accidental or malicious damage.

Software uses CTILAR to set or clear the lock, and CTILSR to check the current status of the lock.

Attributes

CTILAR is a 32-bit register.

Field descriptions

The CTILAR bit assignments are:

313029282726252423222120191817161514131211109876543210
KEY

KEY, bits [31:0]

Lock Access control. Writing the key value 0xC5ACCE55 to this field unlocks the lock, enabling write accesses to this component's registers through a memory-mapped interface.

Writing any other value to this register locks the lock, disabling write accesses to this component's registers through a memory mapped interface.

Accessing the CTILAR

CTILAR can be accessed through a memory-mapped access to the external debug interface:

ComponentOffset
CTI 0xFB0



02/05/2017 15:43

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