Need the FIQ to run at 20Mhz. How?

[smsavage32]

I Need the FIQ (Fast interrupt) to run at 20Mhz.

I can find all sorts of docs that say "When an FIQ interrupt is detected, the ARM core..."

But I haven't been able to find any sources of documentation that tell me how to activate the interrupt.

(Internal clock?, external I/O, counter, timer... ? What)

Does anyone know.

[MarkF]

From what I've read in the 88F6281 documents on this page, the interrupt controller can assert two TYPES of interrupts: either IRQ or FIQ.  The mask bits of each type define which type is generated on each interrupt cause.  That is, based on the FIQ low/high mask settings, a FIQ can be caused by any interrupt source, internal or external.

I don't know if this helps and, of course, I could be completely wrong.