DBGOSDLR, Debug OS Double Lock Register

The DBGOSDLR characteristics are:

Purpose

Locks out the external debug interface.

Configuration

AArch32 System register DBGOSDLR bits [31:0] are architecturally mapped to AArch64 System register OSDLR_EL1[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 AArch32. Otherwise, RW fields in this register reset to architecturally UNKNOWN values.

Attributes

DBGOSDLR is a 32-bit register.

Field descriptions

The DBGOSDLR bit assignments are:

313029282726252423222120191817161514131211109876543210
RES0DLK

Bits [31:1]

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.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 DBGOSDLR

Accesses to this register use the following encodings:

MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}

coprocopc1CRnCRmopc2
0b11100b0000b00010b00110b100

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.<TDE,TDOSA> != '00' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by MDCR_EL2.TDOSA") then AArch64.AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.<TDE,TDOSA> != '00' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by HDCR.TDOSA") then AArch32.TakeHypTrapException(0x05); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDOSA == '1' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by MDCR_EL3.TDOSA") then AArch64.AArch32SystemAccessTrap(EL3, 0x05); else return DBGOSDLR; 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.AArch32SystemAccessTrap(EL3, 0x05); else return DBGOSDLR; elsif PSTATE.EL == EL3 then return DBGOSDLR;

MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}

coprocopc1CRnCRmopc2
0b11100b0000b00010b00110b100

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.<TDE,TDOSA> != '00' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by MDCR_EL2.TDOSA") then AArch64.AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.<TDE,TDOSA> != '00' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by HDCR.TDOSA") then AArch32.TakeHypTrapException(0x05); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TDOSA == '1' && (IsFeatureImplemented("ARMv8.0-DoubleLock") || boolean IMPLEMENTATION_DEFINED "Trapped by MDCR_EL3.TDOSA") then AArch64.AArch32SystemAccessTrap(EL3, 0x05); else DBGOSDLR = R[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.AArch32SystemAccessTrap(EL3, 0x05); else DBGOSDLR = R[t]; elsif PSTATE.EL == EL3 then DBGOSDLR = R[t];




27/09/2019 18:48; 6134483bd14dc8c12a99c984cbfe3431cc1c9707

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