From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerry Van Baren Date: Tue, 8 Mar 2005 11:00:35 -0500 Subject: [U-Boot-Users] RE: Ethernet loopback command In-Reply-To: References: Message-ID: <422DCC23.1090502@smiths-aerospace.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Thomas Sch?fer wrote: > Hi, > >>-----Original Message----- >>From: wd at denx.de [mailto:wd at denx.de] [snip] >>I also don't understand why specific ethernet packet types >>must be invented. I don't like such non-standard solutions. >> > > The PROT_IP part of the NetReceive function examines the complete IP > header which is not necessary here. I introduced that packet type to > achieve a proper separtion from all other packet types. Normally the > generated packet would remain on the board because PHY or EMAC are > switched into loopback mode, but i agree that those non-standard packets > could be problematic when sent to a network. Just a thought... I have not looked at the code, so I don't know how practical/reasonable this thought is... If you sent a "ping" (ICMP echo-request) packet and had your loopback responder return a "ping" response (ICMP echo-reply) this will be a standard packet and may be useful elsewhere. * Ping packet (echo-request) generation and parsing (echo-reply) is already present in u-boot. If you can reuse this code, you are that much further ahead. * If you add a handler for echo-request packets, returning echo-reply packets, this would potentially be useful for responding to external computers "ping" requests (currently not implemented because of limited usefulness and implementation issues). [snip] > Best regards, > > Thomas Sch?fer gvb