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TRCOSLSR, Trace OS Lock Status Register

The TRCOSLSR characteristics are:

Purpose

Returns the status of the Trace OS Lock.

Configuration

External register TRCOSLSR bits [31:0] are architecturally mapped to AArch64 System register TRCOSLSR[31:0].

This register is present only when FEAT_ETE is implemented and FEAT_TRC_EXT is implemented. Otherwise, direct accesses to TRCOSLSR are RES0.

Attributes

TRCOSLSR is a 32-bit register.

Field descriptions

Bits [31:5]

OSLM, bits [4:3, 0]

Bit [2]

OSLK, bit [1]

Accessing TRCOSLSR

External debugger accesses to this register are unaffected by the OS Lock.

TRCOSLSR can be accessed through the external debug interface:

Accessible as follows:

• When !AllowExternalTraceAccess(addrdesc) or !IsTraceCorePowered(), accesses to this register generate an error response.
• Otherwise, accesses to this register are RO.

2026-03-12 12:23:09, 2025-09_rel_asl1

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