Hyp Data Fault Address Register
Holds the virtual address of the faulting address that caused a synchronous Data Abort exception that is taken to Hyp mode.
AArch32 System register HDFAR bits [31:0] are architecturally mapped to AArch64 System register FAR_EL2[31:0].
AArch32 System register HDFAR bits [31:0] are architecturally mapped to AArch32 System register DFAR[31:0] (DFAR_S) when EL2 is implemented, EL3 is implemented, and FEAT_AA64 is not implemented.
This register is present only when FEAT_AA32EL2 is implemented. Otherwise, direct accesses to HDFAR are UNDEFINED.
If EL2 is not implemented, this register is RES0 from EL3.
HDFAR 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 |
| VA | |||||||||||||||||||||||||||||||
VA of faulting address of synchronous Data Abort exception taken to Hyp mode.
On a Prefetch Abort exception, this register is UNKNOWN.
Any execution in a Non-secure EL1 or Non-secure EL0 mode makes this register UNKNOWN.
The reset behavior of this field is:
Accesses to this register use the following encodings in the System register encoding space:
MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
(coproc = 0b1111, opc1 = 0b100, CRn = 0b0110, CRm = 0b0000, opc2 = 0b000)
if !IsFeatureImplemented(FEAT_AA32EL2) 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); else UNDEFINED; elsif PSTATE.EL == EL2 then R[t] = HDFAR; elsif PSTATE.EL == EL3 then if SCR.NS == '0' then UNDEFINED; else R[t] = HDFAR;
MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
(coproc = 0b1111, opc1 = 0b100, CRn = 0b0110, CRm = 0b0000, opc2 = 0b000)
if !IsFeatureImplemented(FEAT_AA32EL2) 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); else UNDEFINED; elsif PSTATE.EL == EL2 then HDFAR = R[t]; elsif PSTATE.EL == EL3 then if SCR.NS == '0' then UNDEFINED; else HDFAR = R[t];
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