On 1/29/2013 9:34 AM, Vikram Narayanan wrote:

On 1/29/2013 1:17 AM, Troy Kisky wrote:

quoted

On 1/28/2013 10:39 AM, Vikram Narayanan wrote:

quoted

Running the latest head <linux-2.6.git> on an i.Mx6Quad based platform
gives me the below error when flooded with ping requests.

== Start log ==
[ 2555.004031] ------------[ cut here ]------------
[ 2555.009740] WARNING: at net/sched/sch_generic.c:254
dev_watchdog+0x298/0x2b8()
[ 2555.018721] NETDEV WATCHDOG: eth0 (fec): transmit queue 0 timed out

I think the tx interrupt status bit was lost. The packets were
transmitted, but the interrupt never
happened. The controller should have been reset here, but perhaps a bug
with the reset code.
Are you using the mainline kernel, or a version Freescale's kernel.

I tried with both the kernels. Freescale's and mainline results in the 
same error.

quoted

mainline fec_restart does not reset tx_full

You can try adding
fep->tx_full = 0;

With this there was no improvement.

I have fixed this bug (and more) on Freescale's kernel 
(imx-3.0.35_1.1.0). I created a branch you can try.
Feel free to port to mainline.

This is the patch that should fix your problem
fec: clear TX_FULL in fec_restart

git://github.com/boundarydevices/linux-imx6.git ethernet_test



Please let me know results.
Thanks
Troy