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IFAR

IFAR, Instruction Fault Address Register

The IFAR characteristics are:

Purpose

Holds the virtual address of the faulting address that caused a synchronous Prefetch Abort exception.

Configuration

This register is banked between IFAR and IFAR_S and IFAR_NS.

AArch32 System register IFAR bits [31:0] are architecturally mapped to AArch64 System register FAR_EL1[63:32].

AArch32 System register IFAR bits [31:0] (IFAR_S) are architecturally mapped to AArch32 System register HIFAR[31:0] when EL2 is implemented and EL3 is implemented.

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

Attributes

IFAR is a 32-bit register.

This register has the following instances:

Field descriptions

313029282726252423222120191817161514131211109876543210
VA

VA, bits [31:0]

VA of faulting address of synchronous Prefetch Abort exception.

The reset behavior of this field is:

Accessing IFAR

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

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

coprocopc1CRnCRmopc2
0b11110b0000b01100b00000b010

if !IsFeatureImplemented(FEAT_AA32EL1) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HSTR_EL2().T6 == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HSTR().T6 == '1' then AArch32_TakeHypTrapException(0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HCR_EL2().TRVM == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HCR().TRVM == '1' then AArch32_TakeHypTrapException(0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) then R(t) = IFAR_NS(); else R(t) = IFAR(); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) then R(t) = IFAR_NS(); else R(t) = IFAR(); end; elsif PSTATE.EL == EL3 then if SCR().NS == '0' then R(t) = IFAR_S(); else R(t) = IFAR_NS(); end; end;

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

coprocopc1CRnCRmopc2
0b11110b0000b01100b00000b010

if !IsFeatureImplemented(FEAT_AA32EL1) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HSTR_EL2().T6 == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HSTR().T6 == '1' then AArch32_TakeHypTrapException(0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HCR_EL2().TVM == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HCR().TVM == '1' then AArch32_TakeHypTrapException(0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) then IFAR_NS() = R(t); else IFAR() = R(t); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) then IFAR_NS() = R(t); else IFAR() = R(t); end; elsif PSTATE.EL == EL3 then if SCR().NS == '0' then IFAR_S() = R(t); else IFAR_NS() = R(t); end; end;


2026-03-12 12:23:09, 2025-09_rel_asl1

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