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ICC_RPR
AArch32 Registers
AArch64 Registers
AArch32 Instructions
AArch64 Instructions
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External Registers
External Registers by Offset
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Proprietary Notice

ICC_RPR, Interrupt Controller Running Priority Register

The ICC_RPR characteristics are:

Purpose

Indicates the Running priority of the CPU interface.

Configuration

AArch32 System register ICC_RPR bits [31:0] performs the same function as AArch64 System register ICC_RPR_EL1[31:0].

This register is present only when FEAT_AA32EL1 is implemented and GICv3 is implemented. Otherwise, direct accesses to ICC_RPR are UNDEFINED.

Attributes

ICC_RPR is a 32-bit register.

Field descriptions

313029282726252423222120191817161514131211109876543210
RES0Priority

Bits [31:8]

Reserved, RES0.

Priority, bits [7:0]

The current running priority on the CPU interface. This is the group priority of the current active interrupt.

The priority returned is the group priority as if the BPR for the current Exception level and Security state was set to the minimum value of BPR for the number of implemented priority bits.

Note

If 8 bits of priority are implemented the group priority is bits[7:1] of the priority.

Accessing ICC_RPR

If there are no active interrupts on the CPU interface, or all active interrupts have undergone a priority drop, the value returned is the Idle priority.

Software cannot determine the number of implemented priority bits from a read of this register.

Accesses to this register use the following encodings in the System register encoding space:

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

coprocopc1CRnCRmopc2
0b11110b0000b11000b10110b011

if !(IsFeatureImplemented(FEAT_AA32EL1) && IsFeatureImplemented(FEAT_GICv3)) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then Undefined(); elsif HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SCR().[IRQ,FIQ] == '11' then Undefined(); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HSTR_EL2().T12 == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HSTR().T12 == '1' then AArch32_TakeHypTrapException(0x03); elsif ICC_SRE().SRE == '0' then Undefined(); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && ICH_HCR_EL2().TC == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && ICH_HCR().TC == '1' then AArch32_TakeHypTrapException(0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HCR_EL2().FMO == '1' then R(t) = ICV_RPR(); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HCR_EL2().IMO == '1' then R(t) = ICV_RPR(); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HCR().FMO == '1' then R(t) = ICV_RPR(); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HCR().IMO == '1' then R(t) = ICV_RPR(); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x03); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SCR().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch32_TakeMonitorTrapException(); end; else R(t) = ICC_RPR(); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then Undefined(); elsif HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SCR().[IRQ,FIQ] == '11' then Undefined(); elsif ICC_HSRE().SRE == '0' then Undefined(); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x03); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SCR().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch32_TakeMonitorTrapException(); end; else R(t) = ICC_RPR(); end; elsif PSTATE.EL == EL3 then if ICC_MSRE().SRE == '0' then Undefined(); else R(t) = ICC_RPR(); end; end;

AArch32 Registers
AArch64 Registers
AArch32 Instructions
AArch64 Instructions
Index by Encoding
External Registers
External Registers by Offset
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2026-03-12 12:23:09, 2025-09_rel_asl1

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