From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 19425 invoked by alias); 3 Jun 2009 14:19:15 -0000 Received: (qmail 19411 invoked by uid 22791); 3 Jun 2009 14:19:14 -0000 X-SWARE-Spam-Status: No, hits=-1.2 required=5.0 tests=AWL,BAYES_00,SARE_MSGID_LONG40,SPF_PASS X-Spam-Check-By: sourceware.org Received: from mail-ew0-f220.google.com (HELO mail-ew0-f220.google.com) (209.85.219.220) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 03 Jun 2009 14:19:07 +0000 Received: by ewy20 with SMTP id 20so8622ewy.33 for ; Wed, 03 Jun 2009 07:19:04 -0700 (PDT) MIME-Version: 1.0 Received: by 10.216.3.195 with SMTP id 45mr356378weh.8.1244038743781; Wed, 03 Jun 2009 07:19:03 -0700 (PDT) In-Reply-To: <20090603135544.GF27508@lunn.ch> References: <5addeae60906030643h354a9c6dq8da568ead5c8c63@mail.gmail.com> <20090603135544.GF27508@lunn.ch> Date: Wed, 03 Jun 2009 14:19:00 -0000 Message-ID: <5addeae60906030719m2848837k2b0099e9cb4d2926@mail.gmail.com> From: Nikolay Marusov To: Nikolay Marusov , ecos-discuss@ecos.sourceware.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact ecos-discuss-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: ecos-discuss-owner@ecos.sourceware.org Subject: Re: [ECOS] ea2468 Ethernet overrun X-SW-Source: 2009-06/txt/msg00018.txt.bz2 2009/6/3 Andrew Lunn : > On Wed, Jun 03, 2009 at 05:43:04PM +0400, Nikolay Marusov wrote: > > Is it an overrun or an underrun? > > I've seen underrun problems before in an intel chipset. The problem > was that the DMA would start transferring the packet from the host RAM > to the ethernet chipset. When X bytes of the packet had arrived at the > ethernet, the ethernet started sending them on the wire. Under heavy > memory load, the DMA was slower than the Ethernet sending bytes on the > wire, and with long packets the ethernet chip would empty its buffer > and then throw an underrun error. I had the change the Ethernet > chipset to have a bigger X so it had more buffered bytes before it > started sending them to the wire. > > Andrew > Yes, it is underrun - sorry. Exactly this case. So thought I. I was interested whether anybody has such a thing at EA2468. If this problem is insuperable, one could use this: In phy_eth_drivers.cdl: cdl_option CYGOPT_DEVS_ETH_PHY_SPEED { display "Preferred speed" flavor data legal_values 10 100 default_value 100 description "This option allows to select the preferred interface speed during auto-negitiation." } In dev/KSZ8001.c: #if CYGOPT_DEVS_ETH_PHY_SPEED == 10 _eth_phy_read(f, PHY_AN_ADV, f->phy_addr, &phy_anadv_reg); _eth_phy_write(f, PHY_AN_ADV, f->phy_addr, (phy_anadv_reg & ~PHY_AN_ADV_100HDX & ~PHY_AN_ADV_100FDX & ~PHY_AN_ADV_100_T4 )| PHY_AN_ADV_10HDX | PHY_AN_ADV_10FDX); #endif Thank you. Nikolay. -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss