This is normal.
We check for 0xffffffff because that is often how a fault is indicated,
when the memory location is read during or immediately after hotplug (or
if the PCI bus is truly faulty). So for most hardware, you see
tmp = read(irq status)
if (!tmp)
return irq-none /* no irq events raised */
if (tmp == 0xffffffff)
return irq-none /* hot unplug or h/w fault */
and the method that determines no interrupt handling is needed.
Regards,
Jeff
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