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AFSR0_EL3

AFSR0_EL3, Auxiliary Fault Status Register 0 (EL3)

The AFSR0_EL3 characteristics are:

Purpose

Provides additional IMPLEMENTATION DEFINED fault status information for exceptions taken to EL3.

Configuration

This register is present only when EL3 is implemented and FEAT_AA64 is implemented. Otherwise, direct accesses to AFSR0_EL3 are UNDEFINED.

Attributes

AFSR0_EL3 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
IMPLEMENTATION DEFINED
IMPLEMENTATION DEFINED

IMPLEMENTATION DEFINED, bits [63:0]

IMPLEMENTATION DEFINED.

The reset behavior of this field is:

Accessing AFSR0_EL3

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

MRS <Xt>, AFSR0_EL3

op0op1CRnCRmop2
0b110b1100b01010b00010b000

if !(HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then Undefined(); elsif PSTATE.EL == EL2 then Undefined(); elsif PSTATE.EL == EL3 then X{64}(t) = AFSR0_EL3(); end;

MSR AFSR0_EL3, <Xt>

op0op1CRnCRmop2
0b110b1100b01010b00010b000

if !(HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then Undefined(); elsif PSTATE.EL == EL2 then Undefined(); elsif PSTATE.EL == EL3 then if IsFeatureImplemented(FEAT_FGWTE3) && FGWTE3_EL3().AFSR0_EL3 == '1' then AArch64_SystemAccessTrap(EL3, 0x18); else AFSR0_EL3() = X{64}(t); end; end;


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

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