Interrupt handling via OpenPIC

Tim Moloney moloney at
Thu Apr 12 03:24:57 EST 2001

I am writing a device driver for a custom PMC card, and I'm having
trouble with the interrupt service routine.

Although the PCI configuration block says that the board's interrupt
is 9, I am receiving interrupt 3.  I know that the OpenPIC is supposed
to remap the interrupts but I don't quite understand the process.
I've looked at the board's users manual and skimmed the Linux kernel
but I can't find a good example of what to do.

Can anyone provide pointers to documentation, example code, etc. that
shows how I can reconcile what the kernel thinks the interrupt is with
what in actually being generated?

Additional info:
I am developing on a Synergy Microsystems VSS4 board.  This is a
quad-G4 VME board that has the following:
  IBM MPIC-2 interrupt controller
  Motorola MPC106 Grackle PCI bridge/memory controller
  Symbios 53c885 Ethernet/SCSI controller
  Tundra Universe II PCI-VME64 bridge
  DEC/Intel 21554 PCI-PCI bridge

Thanks for any help.

Tim Moloney

ManTech Real-time Systems Laboratory
2015 Cattlemen Road
Sarasota, FL  34232
(941) 377-6775 x208

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