[1383] in linux-net channel archive
Re: eth0: Bus master arbitration failure, status 88f2.
daemon@ATHENA.MIT.EDU (Carlos Carvalho)
Thu Nov 16 06:51:37 1995
Date: Wed, 15 Nov 1995 11:16:17 -0200
From: Carlos Carvalho <carlos@snfep1.if.usp.br>
To: linux-net@vger.rutgers.edu
In-Reply-To: <9511150154.AA12968@rhett.3do.com>
Dave Platt (dplatt@rhett.3do.com) wrote on 14 November 1995 17:54:
>> I have a system with Triton chipset and the following cards: Adaptec
>> 2940UW, Diamond Stealth Video VRAM and Adtron 650E plus (uses the AMD
>> Lance PCI chip). They're all PCI cards; there are no ISA ones.
>> I'm getting the msg. eth0: Bus master arbitration failure, status 88f2
>> quite often. The ethernet card is on slot 0. If I move it to another
>> PCI slot it simply doesn't work.
>>
>> Any clues? Is this a hardware defect or a problem intrinsic to this
>> combination of cards?
>
>I'm not certain. The 88F2 status indicates that a memory-access error
>occurred. The PCnet-PCI '970 chip reports a busmaster error if it asks
>for PCI-bus memory access with /REQ, and doesn't get a /GNT grant within
>50 microseconds. This really shouldn't happen in a PCI machine unless you've
>got something pathological taking place.
>
>Any or all of the following might be taking place:
>
>[1] Your motherboard's PCI controller may be defective (either in design, or
> just a bit toasted) and it might not be "seeing" the /REQ requests.
>
> The fact that your ethercard doesn't work in other slots is suspicious.
> Are all of your PCI slots supposed to be busmaster-capable, or are some
> of them slave-only?
The manual says "Four PCI master slots that are fully compliant with
the PCI 2.0 specification". This seems to mean that they're all
busmaster, no?
> Diagnosis method: swap out the motherboard for a different model and
> see if things get better.
Did it, and the same thing happens.
>[2] The Adaptec controller might be hogging the bus in a pathological fashion
> (although I'd be surprised if the PCI controller would permit it
> to do so).
>
> Diagnosis method: swap in a different disk controller model (e.g. an
> ISA type).
I don't have one, but the "arbitration failure" msg also appears
without it. The difference is that without the Adaptec card the ether
card works in other slots as well.
>[3] The Diamond Stealth card might be doing something really strange.
>
> I mention this because certain other PCI busmaster peripherals
>(specifically the NCR 53c810 SCSI controllers) seem to have
>difficulty working in PCI systems that have certain Diamond Stealth
>cards installed. Symbios had to put a workaround in their latest
>SDMS BIOS for the '810.
>
> Diagnosis method: swap in another video card (preferably _not_ a
> Diamond).
I don't have another PCI card, and using a ISA one doesn't help
because we know it's PCI related. I'll try another Diamond card with a
later revision.
>[4] You might have a bad ethercard. The '970 chip is known to require _very_
> careful attention to power-supply and ground-plane layout and bypassing,
> or it can run into trouble on either the PCI bus or the Ethernet due to
> noise and ground bounce. At least one vendor (Boca, may dogs grub up
> their bones) ignored AMD's design recommendations and built their card
> in a way which makes it very unreliable. If you don't see at least
> half-a-dozen surface-mount chip capacitors near the '970 chip, and at
> least a couple of surface-mount tantalums on the board, then your board
> may not meet the AMD recommendations and might be noise-prone.
>
> Diagnosis: swap in a different Ethercard (e.g. an ISA-based Lance, which
> uses the same driver) and see if matters improve.
If only I had one...
>Good luck. Chasing down this sort of problem is a rather nasty job.
Thanks.
