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Too Many Calls To host's MSI Interrupt Handler When Using MSI Interface app_msi_req Signal...


I'm currently using the app_msi_req interface to generate MSI interrupts on the host. 

Should I be using that interface if I'm implementing an Avalon-MM endpoint or should I be using the rxm_irq[0] interface? I ask because I do see my host-driver's interrupt handler called, but it gets call a total of 12 times for a single interrupt pulse.  The clock running the state-machine logic that drives the request signal high is 125 MHz,  which is the same rate as the PCIe core clock.  Why am I seeing these extra calls to the interrupt handler?

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I figured out now that I should be using the rxm_irq lines to drive interrupts from my MM master through the PCIe core to the PCIe interface.  Now, I just need to know the rxm_irq line's signal timing.  Should I pulse it and trust the PCIe core to handle send and ack protocol with the root complex or do I need to implement some logic that will clear the interrupt through the CRA slave interface?