[vortex] hardware TCP/IP checksum

[Donald Becker]

On Wed, 24 Jan 2001, Pierre Phaneuf wrote:

> Donald Becker wrote:
> > > Does the 3Com Vortex driver for Linux supports the TCP/IP checksumming
> > > using the card ASIC?
> > 
> > Old version of 3c59x.c do not, but the driver has supported it for several
> > years.
> 
> Really? This means that the version in current Linux kernels (2.2 and
> onward) have it, or do I have to download a different line of drivers?

Yes, the current drivers have it.  The central code looks like

	skb->protocol = eth_type_trans(skb, dev);
	{		/* Use hardware checksum info. */
		int csum_bits = rx_status & 0xee000000;
		if (csum_bits &&
			(csum_bits == (IPChksumValid | TCPChksumValid) ||
			 csum_bits == (IPChksumValid | UDPChksumValid))) {
			skb->ip_summed = CHECKSUM_UNNECESSARY;
			rx_csumhits++;
		}
	}

> > Second Generation Beowulf Clusters
> 
> Hmm, competition! I work for HNSX Supercomputers... :-)

Watch the supercomputing press releases next week, and let us know when
NEC plans your cluster product. 

Donald Becker				becker@scyld.com
Scyld Computing Corporation		http://www.scyld.com
410 Severn Ave. Suite 210		Second Generation Beowulf Clusters
Annapolis MD 21403			410-990-9993