Knowledge Base Article
RX buffer credit allocation - performance for received requests" (rxbuffer_rxreq_hwtcl) <selection>" is out of range: "Minimum", "Low", "Balanced"
Description
This error message is displayed when opening a Quartus® II v13.1.4 Qsys system in Quartus® II v14.0 or later if the system has an Altera® Avalon®-MM Hard IP for PCI Express® with High or Maximum RX Buffer Credit Allocation chosen.
In addition, when parameterizing the Avalon-MM Hard IP for PCI Express in Quartus® II v14.0 or later, the High and Maximum settings for the Rx Buffer Credit Allocation are not available.
Resolution
Altera® found performance issues with the High and Maximum settings in the Avalon-MM variants. Consequently, these settings have been removed for Arria® V GZ, Arria® 10, and Stratix® V devices from Quartus® II software version 14.0.
These same parameters are scheduled to be removed for Avalon-MM variants in Arria® V and Cyclone® V devices in a future software release.
This change will be reflected in a future version of the user guides.