SPRUJC6A December 2024 – July 2025 AM2752-Q1 , AM2754-Q1
AM275x Interrupt Architecture includes information on how to utilize various interrupts and events in the system and relationships between interrupts and events.
An interrupt is defined as a physical signal which can be routed to the interrupt controller of various processors, which can cause the Interrupt Service Routine (ISR). This physical signal can be either a pulse or level and the polarity can be either negative or positive. And an interrupt is correspondent to an individual wire.
An event is defined as information transported by the event bus or PSI_L bus. Events are coded using an event index. The same event bus or PSI_L bus is used to transport multiple events. An event can also be routed and multiplexed to different locations. Events can’t trigger a processor’s ISR directly. They must go through the Interrupt Aggregator (IA) to convert the event into an interrupt line. For more information, see Interrupt Aggregator (INTAGGR).
The DMA transfer using BCDMA and PktDMA in AM275x can only be triggered using an event. The SoC level interrupt could be used as a BCDMA trigger using L2G logic. Interrupts in the SoC level can’t be used to trigger a pktDMA transfer.
| Processors | Interrupt Controllers |
|---|---|
| R5 core inside R5FSS | Dedicated VIM inside R5FSS |
| HSM | Dedicated NVIC for HSM. HSM receives the same sets of interrupt as TIFS |
AM275x also contains multiple SoC level interrupt routers. The main function of those SoC level interrupt routers is to provide flexibility to select interrupt sources from a large group of interrupt sources. Many places use this feature, such as GPIO interrupts and some time synchronization related interrupts.
AM275x contains two ESM modules. ESM is used to consolidate/monitor the error events in the device. In this document, ESM may also be referred to as ESM0 and WKUP_ESM0.
AM275x also has some chip level glue logic to convert some miscellaneous signals used as interrupt sources. Those miscellaneous signals are normally self-clear signals and do not need to clear after the Interrupt Service Routine (ISR) like the normal interrupts generated by the peripherals.
Interrupt Architecture shows the high level interrupt architecture in AM275x.
