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dfowlkes's avatar
dfowlkes
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4 years ago

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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  • dfowlkes's avatar
    dfowlkes
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    4 years ago

    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?