This sounds exactly like a problem we (and our customers) have seen
here. One of our guys coded-up a fix. I'm attaching it as a diff
against the fec.c that shipped with the 2.4.2_hhl20 kernel (i.e. HardHat
2.0 from MontaVista). I've included 10 lines of context in either
direction to help you place it in your own fec.c version.
I didn't code this myself, so don't blame me if it causes problems! :-)
John
NBLIST at sbcglobal.net wrote:
>
> Hello all,
>
> I am using the fec on the MPC855T on my custom board.
> I seem to be having some weird ethernet configuration
> problems. My eth0 interface comes up only the first
> time. If I "ifconfig down" the eth0 and bring it back
> up by doing "ifconfig up", the eth0 interface shows up
> fine. But ethernet doesnt work anymore. After a couple
> of minutes, I get "tx buffer full" error messages. But
> it always works the first time I boot the linux kernel
> and bring up etho using ifconfig.
>
> What's going on here? Any ideas, clues, tips????
>
> Thank you,
> NB
>
--
John W. Linville
LVL7 Systems, Inc.
-------------- next part --------------
--- fec.c.old Thu May 23 09:34:27 2002
+++ fec.c Thu May 23 09:34:38 2002
@@ -1861,20 +1861,26 @@
bdp->cbd_sc = 0;
bdp->cbd_bufaddr = 0;
bdp++;
}
/* Set the last buffer to wrap.
*/
bdp--;
bdp->cbd_sc |= BD_SC_WRAP;
+ /* Since we have re-initialized the buffer pool, the ring is no longer
+ * full.
+ */
+ fep->tx_full = 0;
+ netif_wake_queue(dev);
+
/* Enable MII mode.
*/
if (duplex) {
fecp->fec_r_cntrl = FEC_RCNTRL_MII_MODE; /* MII enable */
fecp->fec_x_cntrl = FEC_TCNTRL_FDEN; /* FD enable */
}
else {
fecp->fec_r_cntrl = FEC_RCNTRL_MII_MODE | FEC_RCNTRL_DRT;
fecp->fec_x_cntrl = 0;
}
