[microblaze-uclinux] Ethernet performance with xps_ll_temac

["Terry ONeal" <terryoneal3@xxxxxxxxx>]

Hi All, I'm working on a Microblaze system (MMU enabled) that uses xps_ll_temac, and I'm seeing poor network performance when running netperf.  The phy is in 100Mb mode and I'm seeing around 2.5Mb/s with the netperf TCP_STREAM test. Microblaze caches are 16K, temac buffers are 4k, barrell shifter and HW multiplier are turned on. I'm using petalinux sources I pulled from the svn repository on 10/16/08.

What is interesting is that it appears that the kernel is losing timer ticks - if I configure netperf to run the test for 10 seconds, it actually takes 20 seconds (per my watch) to run, but the kernel only thinks it's been runnning for 10 seconds. So it appears the the ll_temac driver is hogging the CPU. 

I also put togther my own application that simply creates a UDP socket and sends data through it as fast as it can - the performance is a bit better than the netperf TCP test but still way off from what I'm expecting (at least 25Mb/s). 

Has anyone had better luck with xps_ll_temac performance? Any suggestions as to what may be going that is limiting the performance?

Thanks,
Terry