From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rask Ingemann Lambertsen Subject: Re: RFC: Enabling ethernet drivers to return FCS in the skb? Date: Mon, 24 Nov 2003 01:05:05 +0100 Sender: netdev-bounce@oss.sgi.com Message-ID: <20031124010501.C1657@sygehus.dk> References: <3FB94311.10004@candelatech.com> <20031119123556.A7622@sygehus.dk> <3FBB8D61.6010106@candelatech.com> <20031120173404.A1538@sygehus.dk> <3FC077B1.1050807@candelatech.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: To: Linux netdev mailing list Content-Disposition: inline In-Reply-To: <3FC077B1.1050807@candelatech.com>; from greearb@candelatech.com on Sun, Nov 23, 2003 at 01:02:41AM -0800 Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org On Sun, Nov 23, 2003 at 01:02:41AM -0800, Ben Greear wrote: [Intel i82557/8/9 Ethernet chips] Saving bad frames to memory is controlled by CB_CFIG_SAVE_BAD_FRAMES in byte 6. Saving the FCS to memory is controlled by CB_CFIG_CRC_IN_MEM in byte 18. See drivers/net/e100/e100_config.h. > It's less clear what happens when you turn off the FCS generation. One part of > the document mentions it gets it from RAM, which I assume means it uses the last > part of the DMA'd packet??? Yes. The last four octets from the skb will be interpreted as an FCS by whichever board receives that frame. > Another explanation of the transmit state machine does > not mention that you can disable FCS generation... I'm going to print this out > and read it again in detail... There is a bit in the command word of a TX command which disables FCS generation. I can't find that bit defined in drivers/net/e100/e100.h, so you'll have to find it in the docs. -- Regards, Rask Ingemann Lambertsen