SPRUI30H November 2015 – May 2024 DRA745 , DRA746 , DRA750 , DRA756
A wake-up dependency is a dependency between the clock domain of a module that owns one or several wake-up signals toward the clock domain of another module needed to service the associated wake-up event. As a result of this dependency, the wake-up event to a module activates not only its clock domain but also the clock domain of the servicing module.
To ensure that the clock domain of the servicing module remains active, the wake-up signal that triggers a wake-up dependency stays active as long as the source of the event is not serviced.
Wake-up dependencies allow acceleration of the wake-up transition of multiple domains needed to service the wake-up event by initiating their transition in parallel. The static and dynamic dependencies can allow the wake-up of related domains, but the complete wake-up transition of all the associated domains is slower because of the sequential cascading of their wake-up transitions.
In the device, the source event of the wake-up signal to a slave module can be either of following types:
Upon wake-up by these types of wake-up events, and for as long as they remain asserted, the PRCM module takes the following actions:
On assertion of a wake-up event of a stand-alone master module, and as long as it remains asserted, the PRCM module takes the following action:
For slave modules, the static and dynamic dependencies of a clock domain are not affected by its wake-up dependency settings. For master modules, the static dependencies are not affected.
Hence, in addition to the activation of the clock domains previously described, all clock domains associated by static dependencies are also activated.
However, the clock domains associated with the wake-up clock domain through dynamic dependencies are activated only if a transaction is initiated to these clock domains.
For each wake-up signal coming from a slave module, the type of the corresponding event can be configured in the PM_<Power domain>_<Originator Module> _WKDEP[x] WKUPDEP_<Originator Module>_[IRQ/DMA]_<Servicing Module> bit of the PRCM module, where <Power domain> is the name of the power domain of the originator module of the wake-up event identified as <Originator Module>. Servicing Module refers to the module servicing the wake-up event.
When only one event type is associated with the wake-up signal of a slave module, the wake-up dependency (WKUPDEP) for the module clock domain is not configurable and may be hardwired in the PRCM module.
For the master modules, there is no configurable wake-up dependency. Their power domain is switched on and their clock domain is activated by the PRCM module when they assert their wake-up signal.