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DFAR

DFAR, Data Fault Address Register

The DFAR characteristics are:

Purpose

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

Configuration

This register is banked between DFAR and DFAR_S and DFAR_NS.

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

AArch32 System register DFAR bits [31:0] (DFAR_S) are architecturally mapped to AArch32 System register HDFAR[31:0] when FEAT_AA32EL2 is implemented and FEAT_AA32EL3 is implemented.

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

Attributes

DFAR 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 Data Abort exception.

The reset behavior of this field is:

Accessing DFAR

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

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

coprocopc1CRnCRmopc2
0b11110b0000b01100b00000b000

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) = DFAR_NS(); else R(t) = DFAR(); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) then R(t) = DFAR_NS(); else R(t) = DFAR(); end; elsif PSTATE.EL == EL3 then if SCR().NS == '0' then R(t) = DFAR_S(); else R(t) = DFAR_NS(); end; end;

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

coprocopc1CRnCRmopc2
0b11110b0000b01100b00000b000

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 DFAR_NS() = R(t); else DFAR() = R(t); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) then DFAR_NS() = R(t); else DFAR() = R(t); end; elsif PSTATE.EL == EL3 then if SCR().NS == '0' then DFAR_S() = R(t); else DFAR_NS() = R(t); end; end;


2026-03-26 20:27:25, 2026-03_rel

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