Implementing pseudo non-masking interrupts behavior using a priority interrupt controller

摘要

A method is provided for handling interrupts in a processor, the interrupts including regular interrupts having a range of priorities and a pseudo non-maskable interrupt (PNMI) that is of a higher priority than any of the regular interrupts. The method includes obtaining an interrupt vector corresponding to a received interrupt, and if the received interrupt is a PNMI, executing a PNMI interrupt handler. If the received interrupt is a regular interrupt, the method further comprises reading a mask flag that indicates whether regular interrupts are enabled in an interrupt controller and further: if the mask flag indicates that regular interrupts are enabled, enabling interrupts in the processor so that a PNMI can be received while handling the regular interrupt, executing, a regular interrupt handler, and disabling interrupts in the processor; and if the mask flag indicates that regular interrupts are disabled, saving the interrupt vector for subsequent handling.