From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from az33egw01.freescale.net (az33egw01.freescale.net [192.88.158.102]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "az33egw01.freescale.net", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 66F9BDDE01 for ; Tue, 30 Sep 2008 16:03:39 +1000 (EST) Message-ID: <48E0E981.60703@freescale.com> Date: Mon, 29 Sep 2008 09:43:13 -0500 From: Scott Wood MIME-Version: 1.0 To: embedded Subject: Re: FCC1 failing on large packet PINGS, while FCC2 is successful References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: linuxppc-embedded@ozlabs.org List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , embedded wrote: > We've found a way to get ping to fail all of the time by increasing > the size of the ping messages. When we use the max in Windows of > 65500, every ping to the first FCC1 Ethernet is dropped. However, > when we ping with a size of 65500 to the second FCC2 Ethernet > everything is fine and all echos are successful. > > In windows: > ping -l 64000 172.24.100.11 -t > > It definitely seems to be a problem with the mpc, but I'm not sure > where to look. Board? KErnel? boot loader? The two Ethernet devices > should be configured identically, and looking through the kernel code, > it seems that there aren't any preferred treatment differences. Could > the problem be in the bit-banging mdio control, or should I look > within fs_enet? We've got this reproducing on all of our boards and > it could also reside in the board setup... > > Does anyone with experience on the ep8248 and/or mpc8272 family, > fs_enet-* code have any ideas where I should look next? It looks very similar to what I was seeing on ep8248 -- the first ethernet port would fail when attempting to receive back-to-back packets. I didn't look into it too closely since I thought it was probably a board issue (I had only one, and the firmware never generated any traffic that resulted in back-to-back receives). I'd be very interested if you ever figure out what's wrong. -Scott