From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eugene Surovegin Subject: Re: [PATCH] net: EMAC: Fix problem with mtu > 4080 on non TAH equipped 4xx PPC's Date: Tue, 15 Jan 2008 12:00:19 -0800 Message-ID: <20080115200019.GA2598@gate.ebshome.net> References: <1200400809-19720-1-git-send-email-sr@denx.de> <20080115173202.GA1268@gate.ebshome.net> <200801152046.01881.sr@denx.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linuxppc-dev@ozlabs.org, netdev@vger.kernel.org, benh@kernel.crashing.org To: Stefan Roese Return-path: Received: from gate.ebshome.net ([208.106.21.240]:59433 "EHLO gate.ebshome.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751823AbYAOUAU (ORCPT ); Tue, 15 Jan 2008 15:00:20 -0500 Content-Disposition: inline In-Reply-To: <200801152046.01881.sr@denx.de> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, Jan 15, 2008 at 08:46:01PM +0100, Stefan Roese wrote: > On Tuesday 15 January 2008, Eugene Surovegin wrote: > > On Tue, Jan 15, 2008 at 01:40:09PM +0100, Stefan Roese wrote: > > > Currently, all non TAH equipped 4xx PPC's call emac_start_xmit() upon > > > xmit. This routine doesn't check if the frame length exceeds the max. > > > MAL buffer size. > > > > > > This patch now changes the driver to call emac_start_xmit_sg() on all > > > platforms and not only the TAH equipped ones (440GX). This enables an > > > MTU of 9000 instead 4080. > > > > > > Tested on Kilauea (405EX) with gbit link -> jumbo frames enabled. > > > > > > Signed-off-by: Stefan Roese > > > --- > > > Eugene & Ben, do you see any problems with this patch? If not, then I'll > > > send another version for the newemac driver too. > > > > Hmm, so why not make GigE support a condition to hook SG version of > > xmit then? I don't like when you change behaviour for chips where it > > perefectly legal not to do this check because you cannot change MTU > > anyways. > > OK. But how do we detect GigE support? Seems like GigE enabled devices have > CONFIG_IBM_EMAC4 defined. If nobody objects I'll fix up another version > tomorrow. Look couple of lines down where I set MTU changing hook. If you cannot change MTU you cannot get big frames. -- Eugene