WFI

Wait For Interrupt is a hint instruction that indicates that the PE can enter a low-power state and remain there until a wakeup event occurs. For more information, see Wait For Interrupt.

As described in Wait For Interrupt, the execution of a WFI instruction that would otherwise cause entry to a low-power state can be trapped to a higher Exception level. See:

313029282726252423222120191817161514131211109876543210
11010101000000110010000001111111
CRmop2

System

WFI

// Empty.

Operation

if !InterruptPending() then if PSTATE.EL == EL0 then // Check for traps described by the OS which may be EL1 or EL2. AArch64.CheckForWFxTrap(EL1, FALSE); if EL2Enabled() && PSTATE.EL IN {EL0, EL1} && !IsInHost() then // Check for traps described by the Hypervisor. AArch64.CheckForWFxTrap(EL2, FALSE); if HaveEL(EL3) && PSTATE.EL != EL3 then // Check for traps described by the Secure Monitor. AArch64.CheckForWFxTrap(EL3, FALSE); WaitForInterrupt();


Internal version only: isa v30.25, AdvSIMD v27.01, pseudocode v85-xml-00bet8_rc3 ; Build timestamp: 2018-09-13T13:25

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