Firewire resets/performance problems

[Brian Candler]

On Sat, Jun 28, 2003 at 02:35:12AM +0900, Hidetoshi Shimokawa wrote:
> > My system also has a SCSI card with a couple of CD-ROMs on it, so that's
> > scbus0 and the firewire is scbus1.
> > 
> > I just tried removing the SCSI card and the firewire is zooming along (8MB
> > per second!)
> > 
> > This may or may not be a red herring - perhaps it's just the fact that I did
> > a reboot - but is it possible that something is wrongly assuming the device
> > to be on scbus0 when it's on scbus1 ?
> > 
> > Regards,
> > 
> > Bran.
> 
> I thinks there is no difference between scbus0 and scbus1 at CAM
> layer. I suspect you have problem in PCI bus and removing the SCSI card
> hides the problem.
> 
> You can easily exchange scbus 0 and 1 without removing the card by
> adding the following line into the kernel config file.
> 
> device        scbus0 at sbp0

Cheers. I have actually done some further reboots, with the SCSI card in
place, and it's intermittent. Sometimes when I boot everything works fine;
sometimes when I boot, and then attach the iPod, I get what appears to be an
infinite loop of:

fwohci0: BUS reset
fwohci0: node_id = 0xc800ffc0, CYCLEMASTER mode
firewire0: 1 nodes, maxhop <= 0, cable IRM = 0 (me)

(logged once per second). In that case it never gets as far as making
detecting da0 and making it available. I did a hard power-cycle of the
machine, without unplugging any cards, and it worked after that.

So now my best guess is that there's something in the Lucent chipset which
is not getting properly initialised.

It seems to work more often than it doesn't, and it works really well when
it does.

Regards,

Brian.