8.2.4. Authentication

The CTI can control access to individual debug events:

Most bits of tinidensel and todbgensel can be tied HIGH, because the components with event interfaces have authentication interfaces and mask the events locally when necessary. This includes connections to other CoreSight components. todbgensel must by tied LOW for trigger outputs that request an interrupt using a direct connection to the processor interrupt request pin, because the processor cannot tell that the interrupt request comes from a debug component.

Most ARM processors either integrate the CTI or ship with a Processor Integration Layer (PIL) that shows how these signals must be connected. For more information, see the documentation for the relevant ARM processor.

When trigger inputs or outputs are masked by this mechanism, they cannot be observed or influenced from the programmer model, including using the integration registers.

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