This instruction is an alias of HINT.

The equivalent instruction is HINT #3

Usage

Wait For Interrupt is a hint instruction that permits the PE to enter a low-power state until one of a number of asynchronous event occurs. For more information, see Wait For Interrupt in the ARMv8-A Architecture Reference Manual.

As described in Wait For Interrupt in the ARMv8-A Architecture Reference Manual, 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:

• Traps to EL1 of EL0 execution of WFE and WFI instructions.
• Traps to EL2 of Non-secure EL0 and EL1 execution of WFE and WFI instructions.
• Traps to EL3 of EL2, EL1, and EL0 execution of WFE and WFI instructions.