DCC Interrupt Enable Register
Enables interrupt requests to be signaled based on the DCC status flags.
AArch32 System register DBGDCCINT bits [31:0] are architecturally mapped to AArch64 System register MDCCINT_EL1[31:0].
This register is present only when FEAT_AA32EL1 is implemented. Otherwise, direct accesses to DBGDCCINT are UNDEFINED.
DBGDCCINT is a 32-bit register.
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| RES0 | RX | TX | RES0 | ||||||||||||||||||||||||||||
Reserved, RES0.
DCC interrupt request enable control for DTRRX. Enables a common COMMIRQ interrupt request to be signaled based on the DCC status flags.
| RX | Meaning |
|---|---|
| 0b0 |
No interrupt request generated by DTRRX. |
| 0b1 |
Interrupt request will be generated on RXfull == 1. |
If legacy COMMRX and COMMTX signals are implemented, then these are not affected by the value of this bit.
The reset behavior of this field is:
DCC interrupt request enable control for DTRTX. Enables a common COMMIRQ interrupt request to be signaled based on the DCC status flags.
| TX | Meaning |
|---|---|
| 0b0 |
No interrupt request generated by DTRTX. |
| 0b1 |
Interrupt request will be generated on TXfull == 0. |
If legacy COMMRX and COMMTX signals are implemented, then these are not affected by the value of this bit.
The reset behavior of this field is:
Reserved, RES0.
Accesses to this register use the following encodings in the System register encoding space:
MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
(coproc = 0b1110, opc1 = 0b000, CRn = 0b0000, CRm = 0b0010, opc2 = 0b000)
if !IsFeatureImplemented(FEAT_AA32EL1) then Undefined(); elsif Halted() && PSTATE.EL != EL0 && ConstrainUnpredictableBool(Unpredictable_IGNORETRAPINDEBUG) then R(t) = DBGDCCINT(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL2().TDCC == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR().TDCC == '1' then AArch32_TakeHypTrapException(0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && MDCR_EL2().[TDE,TDA] != '00' then AArch64_AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR().[TDE,TDA] != '00' then AArch32_TakeHypTrapException(0x05); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch32_TakeMonitorTrapException(); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; else R(t) = DBGDCCINT(); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch32_TakeMonitorTrapException(); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; else R(t) = DBGDCCINT(); end; elsif PSTATE.EL == EL3 then if PSTATE.M != M32_Monitor && SDCR().TDCC == '1' then AArch32_TakeMonitorTrapException(); else R(t) = DBGDCCINT(); end; end;
MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
(coproc = 0b1110, opc1 = 0b000, CRn = 0b0000, CRm = 0b0010, opc2 = 0b000)
if !IsFeatureImplemented(FEAT_AA32EL1) then Undefined(); elsif Halted() && PSTATE.EL != EL0 && ConstrainUnpredictableBool(Unpredictable_IGNORETRAPINDEBUG) then DBGDCCINT() = R(t); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL2().TDCC == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR().TDCC == '1' then AArch32_TakeHypTrapException(0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && MDCR_EL2().[TDE,TDA] != '00' then AArch64_AArch32SystemAccessTrap(EL2, 0x05); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR().[TDE,TDA] != '00' then AArch32_TakeHypTrapException(0x05); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch32_TakeMonitorTrapException(); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; else DBGDCCINT() = R(t); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsFeatureImplemented(FEAT_FGT) && MDCR_EL3().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR().TDCC == '1' then if EL3SDDUndef() then Undefined(); else AArch32_TakeMonitorTrapException(); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3().TDA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x05); end; else DBGDCCINT() = R(t); end; elsif PSTATE.EL == EL3 then if PSTATE.M != M32_Monitor && SDCR().TDCC == '1' then AArch32_TakeMonitorTrapException(); else DBGDCCINT() = R(t); end; end;
Version 2026.06 — Copyright © 2010-2026 Arm Limited or its affiliates.
This site is provided as a community resource and is NOT affiliated with nor endorsed by Arm Limited.