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CTILAR

CTILAR, CTI Lock Access Register

The CTILAR characteristics are:

Purpose

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

The optional 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.

Configuration

CTILAR is in the Debug power domain.

If FEAT_Debugv8p4 is implemented, the Software Lock is not implemented.

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

When CTI Software Lock is implemented:

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.

Otherwise:

313029282726252423222120191817161514131211109876543210
RES0

Otherwise

Bits [31:0]

Reserved, RES0.

Accessing CTILAR

CTILAR can be accessed through the memory-mapped interfaces:

ComponentOffsetInstance
CTI0xFB0CTILAR

Accesses to this register are WO.


2026-03-26 20:27:25, 2026-03_rel

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