4.1.1. Enabling the protection unit

Before the protection unit is enabled, you must program at least one valid protection region. If you do not do this the ARM946E-S can enter a state that is recoverable only by reset.

Setting bit 0 of the CP15 register 1, the control register, enables the protection unit.

When the protection unit is disabled, all instruction fetches are noncachable and all data accesses are noncachable and nonbufferable.

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