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PCI Express*, Networking and Connectivity, Memory Interfaces, DSP IP, and Video IP
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Legacy interrupt issue in pcie hard_ip

Honored Contributor II


we are using altera Pcie hard ip (stratix-4GX). 

We have generated an interrupt using legacy i.e in hard ip we have controlled an interrupt using app_int_req,app_int_ack variables In hard ip. 

we are using Dell 6850 server with linux Os. when we are working with single pcie card our functionality working properly but when we are working with two pcie cards in same server we are getting issue of Non Maskable interrupt and system is going to hang. 

please help us how to handle this issue.
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Honored Contributor II

PCIe core configuration space register address 0x3D defined Interrupt Pin as below: 

- 0x00: No INT x# pin used 

- 0x01: INTA# used 

- 0x02: INTB# used 

- 0x03: INTC# used 

- 0x04: INTD# used 


The Interrupt Pin is default to 0x01: INTA# used. 

When have multiple legacy interrupts, this field might needs to change to avoid conflict.