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AT S1E3A

AT S1E3A, Address Translate Stage 1 EL3 Without Permission checks

The AT S1E3A characteristics are:

Purpose

Performs stage 1 address translation as defined for EL3, while ignoring permissions checks from the given virtual address.

Configuration

This instruction is present only when FEAT_ATS1A is implemented and FEAT_AA64 is implemented. Otherwise, direct accesses to AT S1E3A are UNDEFINED.

Attributes

AT S1E3A is a 64-bit System instruction.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
IA
IA

IA, bits [63:0]

Input address for translation. The resulting address can be read from the PAR_EL1.

Executing AT S1E3A

This system instruction is an alias of the SYS instruction.

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

AT S1E3A, <Xt>

op0op1CRnCRmop2
0b010b1100b01110b10010b010

if !(IsFeatureImplemented(FEAT_ATS1A) && 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 AArch64_AT(X{64}(t), TranslationStage_1, EL3, ATAccess_Any); end;


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

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