2006-11-07 00:52:06

by Joseph Mathewson

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Subject: Strange PCI behaviour on Via K8M800CE chipset Shuttle & sata fails with noapic

Hi

I have a Shuttle SK21G with a Via K8M800CE chipset which has very
strange PCI behaviour on the 2.6.18.1 kernel (stock and Fedora 6). I
have tried both x86_64 and i386 architectures.

There is one PCI slot in which I ultimately want to use a D-Link 580TX
4-port ethernet card (Intel bridge + 4 x sundance driver controllers).
However, even with a simple one-port ethernet card (natsemi driver)
similar behaviour is seen, so I am loathe to blame the card.
Interestingly, the onboard (presumably also PCI) via-rhine card works fine.

The problem is that seemingly randomly, the card in the PCI slot will
either:

1) Work fine (doesn't happen very often unfortunately, when it does will
happen for a few boots in a row). Appears in lspci and /proc/interrupts
and sends packets.
2) Appear in lspci but not appear in /proc/interrupts. Loading the
driver will result in no card found. No interface.

Weirdly, sometimes unloading the NIC module and reloading it causes the
card to be seen. Sometimes not. The behaviour with the 4-port card is
more subtle because of the PCI-PCI bridge aspect, I suspect. With this
behaviour is one of:

1) Works fine.
2) Bridge appears in lspci. None of the bridged network cards appear.
(This is most common of the 3).
3) Bridge appears in lspci. Too many network cards appear! One doesn't
really exist and can't be ifconfig'ed.

My highly technical diagnosis is that Linux is very unhappy about PCI on
this box. As a result I have tried:

pci=routeirq
acpi=off
nolapic
noapic

options. The first three don't work. Unfortunately I don't know
whether the last one would work, because when enabled (or even APIC
disabled in BIOS), the sata_via driver hangs. The boot disk is sata so
I can't get any further... I don't know if this is a separate or
related problem.

Have the latest BIOS etc etc. Apologies for the length, it's just very
weird and difficult to explain because of the randomness.

Joe.


2006-11-07 01:29:12

by Alan

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Subject: Re: Strange PCI behaviour on Via K8M800CE chipset Shuttle & sata fails with noapic

Ar Maw, 2006-11-07 am 00:52 +0000, ysgrifennodd Joseph Mathewson:
> 2) Appear in lspci but not appear in /proc/interrupts. Loading the
> driver will result in no card found. No interface.

In this case does lspci show different values particularly of device or
vendor id. If so you've got a dodgy PCI connector or link somewhere.


2006-11-07 01:33:40

by Joseph Mathewson

[permalink] [raw]
Subject: Re: Strange PCI behaviour on Via K8M800CE chipset Shuttle & sata fails with noapic

Alan Cox wrote:
> Ar Maw, 2006-11-07 am 00:52 +0000, ysgrifennodd Joseph Mathewson:
>
>> 2) Appear in lspci but not appear in /proc/interrupts. Loading the
>> driver will result in no card found. No interface.
>>
>
> In this case does lspci show different values particularly of device or
> vendor id. If so you've got a dodgy PCI connector or link somewhere.
>
>
No, lspci shows _correct_ values. With the single NIC, it will show the
correct device/vendor ID of the NIC. With the multi-port NIC/bridge, it
will show just the Intel bridge (correctly) and not the devices behind
it. It's like it knows it is there but can't talk to it.

Joe.