Samsung S5PC110 Manual page 376

S5PC110_UM
Executing wfi instruction is a mandatory step when entering low-power mode. To make sure the
Caution:
processor does not ignore wfi instruction, it is recommended to make a loop statement around the wfi
instruction. The loop repeatedly calls wfi instruciton until SYSCON_INT_DISABLE field of OTHERS
register to become LOW, which indicates low-power mode entering sequence is completed.
4 POWER MANAGEMENT
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