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Altera_Forum's avatar
Altera_Forum
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15 years ago

legacy support freeze PCIe

I'm try to implement legacy interrupt support in Arria 2 GX. MSI-X working good. But when I try to generate legacy interrupt it's freeze whole PC.

I'm use only two signals from PCIe core. Input is app_int_ack and output app_int_sts. When I need a make interrupt I'm set app_int_sts to 1 and wait for app_int_ack became to 1. After I'm set app_int_sts to 0. But It's don't work.

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    I've tried legacy interrupt in cyclone4 starter kit, and I get the same result. I can only receive 1 interrupt after the logic triggered 10-20.

  • Altera_Forum's avatar
    Altera_Forum
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    I think that the second app_int_ack is the problem, it assert to soon. This means the pcie ip send deassert_inta message right after assert_inta message, a small pulse high of inta may not interrupt the system. Maybe it's a bug of pcie ip core, even the app_int_sts remains high, the app_int_ack will go high twice in a very small period.

  • Altera_Forum's avatar
    Altera_Forum
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    The problem was saved when I used quartus12.1 and regenerated code in qsys.