Why does the Arria 10 Hard IP for PCI Express, configured in Gen3 mode, enter Recovery several times when changing speed to Gen3?

Description

The Arria® 10 Hard IP for PCI Express® core configured in Gen3 mode may undergo several Recovery cycles when changing speed to Gen3.  After a few Recovery cycles, the link stabilizes in the L0 state.  Initial link up to Gen3 is not affected. The Recovery cycles only occur in subsequent speed changes after initial link training to Gen3.

Resolution

This problem will be fixed in a future Quartus® Prime release.