Handling ECRC on completions with a Stratix V Hard IP PCI Express

Both, you look for discontinuity and for timeout. What the application does in reaction to the missing completions is application-specific: For example, if you already fed some data into a consuming fifo received as part of the completions, followed by a timeout, you might be out of luck rerunning the transaction. But if you buffer the whole request in memory and only forward it internally once it is completed, you can rollback the whole or just the remaining read request to re-issue it.

btw, it might be easier to just wait for the timeout and rollback the whole read request, if possible. If one of a couple of completion TLPs is missing, you will most probably not receive all data and run into the timeout.

– Matthias