InterruptAttachEvent Failure

I am using the powerpc with an AMD AM79C973 network chip
and the driver is failing to mount within io-net claiming that it is “Unable
to attach interrupt” according to slogger. This is using QNX v6.1.
I have the source provided with the network ddk so I can see the point
at which the driver fails (it is in init.c at pcnet_init_start_thread) but I
am using a built version of the driver provided with the bsp for the Artesyn
PPC board that we have.
What is the best way to try and find out why this error is occuring?



P.S. If it helps, I have access to the PCI transactions via a PCI
analyser and what I see are config writes to the Base Address registers:

xxxxxx10: 00800001
xxxxxx14: 9FFFFFC0

followed by reads and writes of the Interrupt Line register:

2 reads xxxxxx3C: FF060160
write xxxxxx3C: FF060109
2 reads xxxxxx3C: FF060109
write xxxxxx3C: FF060160
read xxxxxx3C: FF060160
write xxxxxx3C: FF060194

followed by reads then writes to status/command to enable Memory/I_O/Bus

2 reads xxxxxx04: 02900004
write xxxxxx04: 02900007
2 reads xxxxxx04: 02900007
write xxxxxx04: 02900007

finally, the Base Address registers are cleared and the I_O/Memory disabled:

write xxxxxx10: 00000000
write xxxxxx14: 00000000
2 reads xxxxxx04: 02900007
write xxxxxx04: 02900004