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Altera_Forum
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10 years ago

How to configure MSI interrupt

Hi, For PCIe Hard IP, how to setup/configure MSI interrupts? For example, I have DMA read and DMA write transactions, setting up through descriptors. At the last PTR, it sends MSI interrupts....
Altera_Forum's avatar
Altera_Forum
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10 years ago

You need to read *Avalon-MM to PCI Express Interrupt Status Register* to figure out who caused the interrupt.

Normally the root port driver needs to read the Interrupt Status Register port AVL_IRQ_ASSERTED[15:0] at (CRA+0x40) to know which IRQ was active,

each AVL_IRQ_ASSERTED[] bit reflects the value on the corresponding IRQ input port.

Value 0 means Avalon-MM IRQ is not being signaled, value 1 means Avalon-MM IRQ is being signaled.