2.4.4 CPU_WAIT control

Each core in the system has an associated CPU_WAIT register. The register controls the core if it starts running boot code when it wakes.

Caution:

The only way for a core to enter a lower-power state is to enter into WFI:

  • If after powering up, CPU_WAIT is held HIGH, the core is not be able to run code to enter WFI, and the core remains powered up.

    To prevent the core from being on indefinitely, if CPU_WAIT is HIGH, ensure that there is at least another agent in the system that can clear this register to allow the core to start up boot.

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