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] .

This register is in the Warm reset domain. Some or all RW fields of this register have defined reset values. On a Warm or Cold reset these apply only if the PE resets into an Exception level that is using AArch32. Otherwise, on a Warm or Cold reset 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];




27/03/2019 21:59; e5e4db499bf9867a4b93324c4dbac985d3da9376

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