2011-03-04 12:31:58     Slow networking on BF527 Svn

Document created by Aaronwu Employee on Aug 26, 2013
Version 1Show Document
  • View in full screen mode

2011-03-04 12:31:58     Slow networking on BF527 Svn

Ciaran Watterson (IRELAND)

Message: 98653   


Working on adding a new 527 target to ucLinux. I've built up the board files for the latest release version and I've just updated to the SVN trunk version. I've been testing the USB ethernet gadget driver and an SMSC network chip with a simple TCP/IP sockets based application.


This works just fine on the Release version about 5MB/s for usb and 12MB/s meaningful throughput for ethernet. However with the SVN version, the usb barely works at all, and some kind of exception happens when loading the g_ether module. Rebooting the system and testing with ethernet only (therefore clean I should think) - the board only manages about 3MB/s.


Settings were copied from the old version. There is also a warning about a missing dependency for USB-OTG which is USB_SUSPEND. Net-tools causes a build issue also, but since these are already in Busybox I disabled them.  I've checked through the various config options for anything new/wrongly set and I can't find anything. Will come back with some debug messages, but they're not very meaningful.




2011-03-04 16:30:02     Re: Slow networking on BF527 Svn

Mike Frysinger (UNITED STATES)

Message: 98659   


you're only seeing issues with the USB network driver ?  or are you seeing issues with the on-chip EMAC too ?  you say "SMSC network chip", but it isnt clear what exactly that is ... async mapped EMAC/PHY ?  just a PHY that's connected to the on-chip EMAC ?  something else ?




2011-03-07 11:02:32     Re: Slow networking on BF527 Svn

Ciaran Watterson (IRELAND)

Message: 98684   


Hi Mike I did this test again and there's no issue with the real networking, the network board I'm using just uses the bfin_mac driver module. No the issue seems to be only with the g_ether driver. I can ping as per usual, but when I run the socket app it fails after only a few messages. I'll get you some more verbose messages on that, for the moment I've included the error messages when the g_ether module is loaded.






2011-03-07 11:51:36     Re: Slow networking on BF527 Svn

Mike Frysinger (UNITED STATES)

Message: 98685   


we'll have someone look at it, but for people who want a stable release to work on, we suggest you use the 2010R1 branch rather than trunk


please run `make bugreport` and post the tarball as an attachment too




2011-03-07 22:53:24     Re: Slow networking on BF527 Svn

Sonic Zhang (CHINA)

Message: 98698   


A bug is filed at   blackfin.uclinux.org/gf/tracker/6503


We will take a look.




2011-03-08 04:07:02     Re: Slow networking on BF527 Svn

Ciaran Watterson (IRELAND)

Message: 98719   


Actually have both on the go at the moment, but I wanted to see did the latest version work also if the changes I made were added.


The bug report attached is run without net-tools enabled. Testing the socket app again with usb - there are no errors, just it is very slow and eventually blocks on reading from the socket - while the client (PC) shortly after times out trying to write.






2011-03-15 23:20:44     Re: Slow networking on BF527 Svn

Bob Liu (CHINA)

Message: 98954   


I think patch "usb: musb: disable double buffering when it's broken"

haven't updated in our svn trunk currently caused this problem.

The patch link is:



There are two solution:

1. Waitting for kernel update

2. Try attached patch for drivers/usb/musb/musb_gadget.c