EDLSR, External Debug Lock Status Register

The EDLSR characteristics are:

Purpose

Indicates the current status of the software lock for external debug registers.

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

Configuration

If FEAT_DoPD is implemented, Software Lock is not implemented by the architecturally-defined debug components of the PE in the Core power domain.

If FEAT_DoPD is not implemented, this register is in the Debug power domain.

Software uses EDLAR to set or clear the lock, and EDLSR to check the current status of the lock.

Attributes

EDLSR is a 32-bit register.

Field descriptions

313029282726252423222120191817161514131211109876543210
RES0nTTSLKSLI

Bits [31:3]

Reserved, RES0.

nTT, bit [2]

Not thirty-two bit access required. RAZ.

SLK, bit [1]
When Software Lock is implemented:

Software Lock status for this component. For an access to LSR that is not a memory-mapped access, or when Software Lock is not implemented, this field is RES0.

For memory-mapped accesses when Software Lock is implemented, possible values of this field are:

SLKMeaning
0b0

Lock clear. Writes are permitted to this component's registers.

0b1

Lock set. Writes to this component's registers are ignored, and reads have no side effects.

The reset behavior of this field is:


Otherwise:

Reserved, RAZ.

SLI, bit [0]

Software Lock implemented. For an access to LSR that is not a memory-mapped access, this field is RAZ. For memory-mapped accesses, the value of this field is IMPLEMENTATION DEFINED. Permitted values are:

SLIMeaning
0b0

Software Lock not implemented or not memory-mapped access.

0b1

Software Lock implemented and memory-mapped access.

Accessing EDLSR

EDLSR can be accessed through the memory-mapped interfaces:

ComponentOffsetInstance
Debug0xFB4EDLSR

This interface is accessible as follows:


05/07/2022 17:07; b0421fa9a8865165f9b91af9b4a566111f866305

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