6.2-RELEASE em0 watchdog timeouts -- sometimes (w/ partial workaround)

[Jack Vogel]

On 1/16/07, Jeremy Chadwick <koitsu at freebsd.org> wrote:
> On Tue, Jan 16, 2007 at 10:53:04AM -0800, Jack Vogel wrote:
> > There are some management related issues with this NIC, first if you
> > have not done so make a DOS bootable device, and run this app I
> > am enclosing, it fixes the prom setting that is wrong on some devices.
> > It will do no harm, and it may solve things.
>
> Jack,
>
> Can you expand on what this application changes in the PROM?  I have
> an Intel motherboard which suffers from similar to what the OP has
> reported (em0 watchdog timeouts), and was curious what the utility
> does before firing up the board and trying it.  Others may be curious
> to know, too.

Hmmm, I'm rusty on this, its now been a year or more since I was
first involved in the details, so I may need to amend this later :)

But from memory, the issue is the value programmed into the MANC
register by the PROM, I don't remember what bit it was, but one bit
is mistakenly set, it causes the hardware to incorrectly intercept some
packets.

I was snowbound today, but I'll doublecheck on the detail tomorrow
and amend if needed.

Everyone note that this ONLY effects an 82573 NIC, so make sure of
that before anything else.

Cheers,

Jack