-/* A lot of complication here is taken away because:
- *
- * 1) We handle one interrupt and return, sitting in a loop and moving across
- * all the pending IRQ bits in the cause register is _NOT_ the answer, the
- * common case is one pending IRQ so optimize in that direction.
- *
- * 2) We need not check against bits in the status register IRQ mask, that
- * would make this routine slow as hell.
- *
- * 3) Linux only thinks in terms of all IRQs on or all IRQs off, nothing in
- * between like BSD spl() brain-damage.
- *