Hi, Does anybody already succeeded in getting full TX bandwidth on a TSEC interface, transmitting 1500 bytes frames at netdev level (ie calling directly dev_queue_xmit(skb)) for instance ?
With default Gianfar driver parameters, I can transmit only around 870Mb/s (while reception side is idle). The other TSEC interface is used only to control a telnet terminal (~1Kb/s), the CPU is idle 60%, 6000irq/s. I must decrease TX threshold value from 1024 to 128 to get 960Mb/s. The problem is that decreasing the TX threshold under 512 bytes has a dramatic side effect: the Gianfar driver generates "TX underrun" events as soon as I start, in parallel, a DMA transfer from memory to memory. Rather disappointing behavior from a PQ3 at 825MHz :-( Any idea how to get full TX bandwidth _without_ modifying this parameter? Thanks. -- sylvain
