Access to DPPI channels can be restricted. A channel can be declared as secure so that only secure peripherals can access it.
The security attribute of a DPPI channel is configured in DPPI[n].PERM (n=0..0). When the secure attribute is set for a channel, only peripherals that have the secure attribute set will be able to publish events to this channel or subscribe to this channel to receive tasks.
The DPPI controller peripheral (DPPIC) is a split security peripheral, i.e., its security behavior depends on the security attributes of both the DPPIC and the accessing party. See Special considerations regarding the DPPIC configuration registers for more information about the DPPIC security behavior.
If a non-secure peripheral wants to publish an event on a secure DPPI channel, the channel will ignore the event. If a non-secure peripheral subscribes to a secure DPPI channel, it will not receive any events from this channel. The following figure illustrates the principle of operation of the security logic for a subscribed channel:
No error reporting mechanism is associated with the DPPI access control logic.