Subject: bge(4) tcp4csum problem -- driver problem or chip problem???
To: None <tech-kern@netbsd.org>
From: Brian Buhrow <buhrow@lothlorien.nfbcal.org>
List: tech-kern
Date: 12/07/2006 11:40:10
	Hello.  I have a series of Sun V20Z servers with the following
Broadcom chips on them, as reported by the bge(4) driver.

bge0 at pci2 dev 2 function 0: Broadcom BCM5703X Gigabit Ethernet
bge0: interrupting at irq 5
bge0: ASIC BCM5703 A2 (0x1002), Ethernet address 00:09:3d:00:18:26
brgphy0 at bge0 phy 1: BCM5703 1000BASE-T media interface, rev. 2

	This is under NetBSD-3, with the driver revision:
$NetBSD: if_bge.c,v 1.87.2.4 2005/11/22 20:44:22 tron Exp

	With hardware tcp4 checksumming enabled, I see a large number of tcp
packets discarded for checksum errors.  With tcp4csum turned off, I still
see occasional errors, but more like I'm used to seeing on various servers
on the Net.  Is this a possible bug in the bge(4) driver, a bug on the chip
itself, and how can I tell the difference?
For the record, ip4csum and udp4csum seem to work fine with this driver and
chip revision.
Any help would be greatly appreciated.
-thanks
-Brian