Open Source Summit + Embedded Linux Conference + OSPOCon 2021

Interrupt and interrupts handlers are important part of embedded system’s efficient functioning. Linux provide a robust subsystem to effectively handle various interrupt type and trigger levels. A good understanding of the IRQ subsystem helps in implementation of low latency and better performing device drivers. The generic interrupt handling layer is designed to provide a complete abstraction of interrupt handling for device drivers. It is able to handle all the different types of interrupt controller hardware. Device drivers use generic API functions to request, enable, disable and free interrupts. The drivers do not have to know anything about interrupt hardware details, so they can be used on different platforms without code changes. In this session Priya will talk about internals of Linux IRQ subsystem (IRQ domain, IRQ descriptors, high level IRQ handlers etc.), how different interrupt controllers are mapped to this generic interrupt subsystem, what APIs are exposed to Device drivers etc. This session will also cover the robust debugfs system of Linux IRQ subsystem and how it will help developers in debugging interrupt related issues. This will help audience to understand the subsystem and intern help in writing efficient interrupt handlers for the devices.