I am implementing A53 dual core processor with GIC-400. I would like to connect the watchdog timer interrupt request to a non-maskable A53 or GIC-400 interrupt input but I realize there isn't one. Should I use nSEI [1:0]?
The A53 processor does not have a non-maskable interrupt (NMI) input. If you need to connect the watchdog timer interrupt to a non-maskable interrupt input, you could consider using the nFIQ (nFast Interrupt Request) signal. However, keep in mind that the nFIQ signal is not recommended for normal interrupt handling.
Alternatively, you could use a regular interrupt input and configure the interrupt priority appropriately. The A53 processor has several interrupt inputs, including IRQ and FIQ, which can be used for this purpose. You could consult the processor's documentation to determine which interrupt input is most appropriate for your specific use case.
In summary, there is no specific A53 interrupt signal that is designed for watchdog timeout. You could use a regular interrupt input and configure the interrupt priority, or consider using the nFIQ signal if necessary.