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PFAR_EL2: Physical Fault Address Register (EL2)

Purpose

Records the faulting physical address for a synchronous External abort, or SError exception taken to EL2.

Configuration

This register is present only when FEAT_PFAR is implemented. Otherwise, direct accesses to PFAR_EL2 are UNDEFINED.

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

Attributes

PFAR_EL2 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
NSNSERES0PA[55:52]PA[51:48]PA
PA

NS, bit [63]

When FEAT_RME is implemented:

Together with PFAR_EL2.NSE, reports the physical address space of the access that triggered the exception.

NSENSMeaning
0b00b0When Secure state is implemented, Secure. Otherwise reserved.
0b00b1Non-secure.
0b10b0Reserved.
0b10b1Realm.

The reset behavior of this field is:



When EL3 is implemented:

Non-secure. Reports the physical address space of the access that triggered the exception.

NSMeaning
0b0

Secure physical address space.

0b1

Non-secure physical address space.

The reset behavior of this field is:



Otherwise:

Reserved, RES0.

NSE, bit [62]

When FEAT_RME is implemented:

Together with PFAR_EL2.NS, reports the physical address space of the access that triggered the exception.

For a description of the values derived by evaluating NS and NSE together, see MFAR_EL3.NS.

The reset behavior of this field is:



Otherwise:

Reserved, RES0.

Bits [61:56]

Reserved, RES0.

PA[55:52], bits [55:52]

When FEAT_D128 is implemented:

When FEAT_D128 is implemented, extension to PFAR_EL2.PA[47:0].

The reset behavior of this field is:



Otherwise:

Reserved, RES0.

PA[51:48], bits [51:48]

When FEAT_LPA is implemented:

When FEAT_LPA is implemented, extension to PFAR_EL2.PA[47:0].

The reset behavior of this field is:



Otherwise:

Reserved, RES0.

PA, bits [47:0]

Physical Address. Bits [47:0] of the aborting physical address.

For implementations with fewer than 48 physical address bits, the corresponding upper bits in this field are RES0.

The recorded address can be any address within the same naturally-aligned fault granule as the faulting physical address, where the size of the fault granule is IMPLEMENTATION DEFINED and no larger than the larger than:

The reset behavior of this field is:

Accessing PFAR_EL2

When the Effective value of HCR_EL2.E2H is 1, without explicit synchronization, accesses from EL2 using the register name PFAR_EL2 or PFAR_EL1 are not guaranteed to be ordered with respect to accesses using the other register name.

PFAR_EL2 is not valid and reads UNKNOWN if ESR_EL2.PFV is recorded as 0.

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

MRS <Xt>, PFAR_EL2

op0op1CRnCRmop2
0b110b1000b01100b00000b101

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EffectiveHCR_EL2_NVx() IN {'xx1'} then AArch64.SystemAccessTrap(EL2, 0x18); else UNDEFINED; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.PFAREn == '0' then UNDEFINED; elsif HaveEL(EL3) && SCR_EL3.PFAREn == '0' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else X[t, 64] = PFAR_EL2; elsif PSTATE.EL == EL3 then X[t, 64] = PFAR_EL2;

MSR PFAR_EL2, <Xt>

op0op1CRnCRmop2
0b110b1000b01100b00000b101

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EffectiveHCR_EL2_NVx() IN {'xx1'} then AArch64.SystemAccessTrap(EL2, 0x18); else UNDEFINED; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.PFAREn == '0' then UNDEFINED; elsif HaveEL(EL3) && SCR_EL3.PFAREn == '0' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else PFAR_EL2 = X[t, 64]; elsif PSTATE.EL == EL3 then PFAR_EL2 = X[t, 64];