From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-out.m-online.net (mail-out.m-online.net [212.18.0.9]) by ozlabs.org (Postfix) with ESMTP id 9AE11DDFB7 for ; Thu, 7 May 2009 08:12:53 +1000 (EST) To: Grant Likely From: Wolfgang Denk Subject: Re: [PATCH 03/12] fs_enet: Add FEC TX Alignment workaround for MPC5121. Mime-version: 1.0 Content-type: text/plain; charset=ISO-8859-1 In-reply-to: References: <1241640919-4650-1-git-send-email-wd@denx.de> <1241640919-4650-4-git-send-email-wd@denx.de> Date: Thu, 07 May 2009 00:12:50 +0200 Message-Id: <20090506221250.C977183420E8@gemini.denx.de> Cc: Piotr Ziecik , Detlev Zundel , netdev@vger.kernel.org, linuxppc-dev@ozlabs.org, John Rigby List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Dear Grant Likely, In message you wrote: > > > The FEC on 5121 has problems with misaligned tx buffers. > > The RM says any alignment is ok but empirical results > > show that packet buffers ending in 0x1E will sometimes > > hang the FEC. Other bad alignment does not hang but will > > cause silent TX failures resulting in about a 1% packet > > loss as tested by ping -f from a remote host. > > > > This patch is a work around that copies every tx packet > > to an aligned skb before sending. > > OUCH! Yes :-( > > +#else > > +#define tx_skb_align_workaround(dev, skb) (skb) > > +#endif > > Another use of #ifdef blocks. What is the multiplatform impact? Hm... Can you recommend a better way to solve the problem? Suggestions are welcome. Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de You don't have to worry about me. I might have been born yesterday... but I stayed up all night.