Wait for interrupt with timeout
This instruction provides a hint that the PE can enter a low-power state and remain there until either a local timeout event or a wakeup event occurs. For more information, see Wait For Interrupt.
As described in Wait For Interrupt, the execution of a WFIT instruction that would otherwise cause entry to a low-power state can be trapped to a higher Exception level.
| 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 |
| 1 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | Rd | ||||
| CRm | op2 | ||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_WFxT) then EndOfDecode(Decode_UNDEF); end; let d : integer = UInt(Rd);
let localtimeout : integer = UInt(X{64}(d)); if Halted() && ConstrainUnpredictableBool(Unpredictable_WFxTDEBUG) then ExecuteAsNOP(); end; Hint_WFIT(localtimeout);
2026-03_rel 2026-03-26 20:48:11
Copyright © 2010-2026 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.