OSLAR_EL1, OS Lock Access Register

The OSLAR_EL1 characteristics are:

Purpose

Used to lock or unlock the OS lock.

This register is part of the Debug registers functional group.

Configuration

AArch64 System register OSLAR_EL1 is architecturally mapped to AArch32 System register DBGOSLAR.

AArch64 System register OSLAR_EL1 is architecturally mapped to External register OSLAR_EL1.

Attributes

OSLAR_EL1 is a 32-bit register.

Field descriptions

The OSLAR_EL1 bit assignments are:

313029282726252423222120191817161514131211109876543210
0000000000000000000000000000000OSLK

Bits [31:1]

Reserved, RES0.

OSLK, bit [0]

On writes to OSLAR_EL1, bit[0] is copied to the OS lock.

Use OSLSR_EL1.OSLK to check the current status of the lock.

Accessing the OSLAR_EL1

This register can be written using MSR (register) with the following syntax:

MSR <systemreg>, <Xt>

This syntax uses the following encoding in the System instruction encoding space:

<systemreg> op0op1CRnCRmop2
OSLAR_EL11000000010000100

Accessibility

The register is accessible as follows:

Control Accessibility
E2HTGENSEL0EL1EL2EL3
xx0 - WO n/a WO
x01 - WOWOWO
x11 - n/a WOWO

This table applies to all instructions that can access this register.

Traps and enables

For a description of the prioritization of any generated exceptions, see section D1.13.2 (Synchronous exception prioritization) in the ARM® Architecture Reference Manual, ARMv8, for ARMv8-A architecture profile. Subject to the prioritization rules, the following traps and enables are applicable when accessing this register.

When EL2 is implemented and is using AArch64 and SCR_EL3.NS==1 :

When EL3 is implemented and is using AArch64 :




18/04/2017 17:00

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