Re: [bug] e100 bug: checksum mismatch on 82551ER rev10

[Auke Kok <auke-jan.h.kok@intel.com>]

Molle Bestefich wrote:
> I'm trying to get Linux running on a Nokia IP130 box.
> 
> The 3x Intel i82551ER NICs doesn't work.
> 
> Apply this patch which just removes the error return path (and adds a
> little debug info):
> 
> ===============================================================
> --- drivers/net/e100.c.orig     2006-07-09 12:03:14.000000000 +0200
> +++ drivers/net/e100.c  2006-07-09 12:03:22.000000000 +0200
> @@ -756,8 +756,7 @@
>         * the sum of words should be 0xBABA */
>        checksum = le16_to_cpu(0xBABA - checksum);
>        if(checksum != nic->eeprom[nic->eeprom_wc - 1]) {
> -               DPRINTK(PROBE, ERR, "EEPROM corrupted\n");
> -               return -EAGAIN;
> +               DPRINTK(PROBE, ERR, "EEPROM corrupted (stored: %4.4x, 
> calc'ed: %
> 4.4x)\n", nic->eeprom[nic->eeprom_wc - 1], checksum);
>        }
> 
>        return 0;
> ===============================================================
> 
> And everything works!
> 
> I think I've heard about this bug before, but I don't know why it occurs.
> So the best I can do is the above (ignore failed EEPROM checksum test).

[removed scott feldman since he's not maintained e100 for a long time now]

Hi,


If you have received a motherboard or card with a broken EEPROM then your card 
is in a limbo state - it might work but results are unreliable and may cause 
your entire system to break (and even data corruption).

You should contact the hardware vendor and have the board replaced or upgraded 
with a proper EEPROM. Continuing to work with the corrupted EEPROM image that 
you have now can seriously hurt you later on.

Cheers,

Auke