HDFAR, Hyp Data Fault Address Register

The HDFAR characteristics are:

Purpose

Holds the virtual address of the faulting address that caused a synchronous Data Abort exception that is taken to Hyp mode.

Configuration

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] (S) when EL2 is implemented, EL3 is implemented and the highest implemented Exception level is using AArch32 state.

This register is present only when AArch32 is supported at any Exception level. Otherwise, direct accesses to HDFAR are UNDEFINED.

If EL2 is not implemented, this register is RES0 from EL3.

Attributes

HDFAR is a 32-bit register.

Field descriptions

The HDFAR bit assignments are:

313029282726252423222120191817161514131211109876543210
VA of faulting address of synchronous Data Abort exception taken to Hyp mode

Bits [31:0]

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.

On a Warm reset, this field resets to an architecturally UNKNOWN value.

Accessing the HDFAR

Accesses to this register use the following encodings:

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

coprocopc1CRnCRmopc2
0b11110b1000b01100b00000b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T6 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T6 == '1' then AArch32.TakeHypTrapException(0x03); else UNDEFINED; elsif PSTATE.EL == EL2 then return HDFAR; elsif PSTATE.EL == EL3 then if SCR.NS == '0' then UNDEFINED; else return HDFAR;

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

coprocopc1CRnCRmopc2
0b11110b1000b01100b00000b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T6 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && 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];




30/09/2020 15:07; ccead0cb9f089f9ceec50268e82aec9e71047211

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