3.2.4. Rules for changing Exception state

This introduction to moving between Execution states does not consider exceptions caused by debug events.

The Execution state, AArch64 or AArch32, can change only on a change of Exception level, meaning it can change only on either:

Note

The Execution state cannot change if, on taking an exception or on returning from an exception, the Exception level remains the same.

On taking an exception to a higher Exception level, the Execution state:

On returning from an exception to a lower Exception level, the Execution state:

On powerup and on reset, the processor enters EL3, the highest Exception level. The Execution state for this Exception level is controlled by the configuration input signal, AA64nAA32. For the other Exception levels the Execution state is determined as follows:

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