For the Arria® V and Cyclone® V device families, to ensure consistent behavior between the Avalon®-MM and Avalon-ST PCI Express® Hard IP, 2 parameters need to be changed from the Avalon-MM wrapper to match the default values in the Avalon-ST wrapper.
In the file altpcie_sv_hip_avmm_hwtcl.v, look for the following parameter definitions near the top of the file (around line 148) and make the changes identified:
parameter rx_cdc_almost_full_hwtcl = 6,
parameter tx_cdc_almost_full_hwtcl = 6,
Change to:
parameter rx_cdc_almost_full_hwtcl = 12,
parameter tx_cdc_almost_full_hwtcl = 12,