ARM Cortex-A35 User Manual

A4.14 Event communication using WFE or SEV
An external agent can use the EVENTI pin to participate in a WFE or SEV event communication with
the Cortex‑A35 processor.
When this pin is asserted, it sends an event message to all the cores in the device. This is similar to
executing a SEV instruction on one core in the cluster. This enables the external agent to signal to the
cores that it has released a semaphore and that the cores can leave the WFE low-power state. The
EVENTI input pin must remain HIGH for at least one CLKIN clock cycle to be visible by the cores.
The external agent can determine that at least one of the cores in the cluster has executed an SEV
instruction by checking the EVENTO pin. When SEV is executed by any of the cores in the cluster, an
event is signaled to all the cores in the device, and the EVENTO pin is asserted. This pin is asserted
HIGH for three CLKIN clock cycles when any core in the cluster executes an SEV instruction.
A4 Power Management
A4.14 Event communication using WFE or SEV
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ARM Cortex-A35 Specifications

General

Brand	ARM
Model	Cortex-A35
Category	Computer Hardware
Language	English