You copied the Doc URL to your clipboard.

OSDLR_EL1, OS Double Lock Register

The OSDLR_EL1 characteristics are:

Purpose

Used to control the OS Double Lock.

Configuration

AArch64 System register OSDLR_EL1 bits [31:0] are architecturally mapped to AArch32 System register DBGOSDLR[31:0] .

Some or all RW fields of this register have defined reset values. These apply only if the PE resets into an Exception level that is using AArch64. Otherwise, RW fields in this register reset to architecturally UNKNOWN values.

Attributes

OSDLR_EL1 is a 64-bit register.

Field descriptions

The OSDLR_EL1 bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
RES0
RES0DLK
313029282726252423222120191817161514131211109876543210

Bits [63:1]

Reserved, RES0.

DLK, bit [0]

When ARMv8.0-DoubleLock is implemented:

OS Double Lock control bit.

DLKMeaning
0b0

OS Double Lock unlocked.

0b1

OS Double Lock locked, if DBGPRCR_EL1.CORENPDRQ (Core no powerdown request) bit is set to 0 and the PE is in Non-debug state.

On a Warm reset, this field resets to 0.


Otherwise:

Reserved, RAZ/WI.

Accessing the OSDLR_EL1

Accesses to this register use the following encodings:

MRS <Xt>, OSDLR_EL1

op0op1CRnCRmop2
0b100b0000b00010b00110b100
if PSTATE.EL == EL0 then
    UNDEFINED;
elsif PSTATE.EL == EL1 then
    if EL2Enabled() && !ELUsingAArch32(EL2) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && IsFeatureImplemented("ARMv8.0-DoubleLock") && HDFGRTR_EL2.OSDLR_EL1 == '1' then
        AArch64.SystemAccessTrap(EL2, 0x18);
    elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.<TDE,TDOSA> != '00' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by MDCR_EL2.TDOSA") then
        AArch64.SystemAccessTrap(EL2, 0x18);
    elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDOSA == '1' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by MDCR_EL3.TDOSA") then
        AArch64.SystemAccessTrap(EL3, 0x18);
    else
        return OSDLR_EL1;
elsif PSTATE.EL == EL2 then
    if HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDOSA == '1' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by MDCR_EL3.TDOSA") then
        AArch64.SystemAccessTrap(EL3, 0x18);
    else
        return OSDLR_EL1;
elsif PSTATE.EL == EL3 then
    return OSDLR_EL1;
              

MSR OSDLR_EL1, <Xt>

op0op1CRnCRmop2
0b100b0000b00010b00110b100
if PSTATE.EL == EL0 then
    UNDEFINED;
elsif PSTATE.EL == EL1 then
    if EL2Enabled() && !ELUsingAArch32(EL2) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && IsFeatureImplemented("ARMv8.0-DoubleLock") && HDFGWTR_EL2.OSDLR_EL1 == '1' then
        AArch64.SystemAccessTrap(EL2, 0x18);
    elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.<TDE,TDOSA> != '00' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by MDCR_EL2.TDOSA") then
        AArch64.SystemAccessTrap(EL2, 0x18);
    elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDOSA == '1' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by MDCR_EL3.TDOSA") then
        AArch64.SystemAccessTrap(EL3, 0x18);
    else
        OSDLR_EL1 = X[t];
elsif PSTATE.EL == EL2 then
    if HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDOSA == '1' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by MDCR_EL3.TDOSA") then
        AArch64.SystemAccessTrap(EL3, 0x18);
    else
        OSDLR_EL1 = X[t];
elsif PSTATE.EL == EL3 then
    OSDLR_EL1 = X[t];
              


Was this page helpful? Yes No