sio: lots of silo overflows on Asus K8V with Moxa Smartio C104H/PCI solved

[Burkard Meyendriesch]

On Fri, 30 Apr 2004 10:51:41 -0700 othermark wrote:
>
> Burkard Meyendriesch wrote:
> > 
> > Meanwhile I plugged the Moxa board into another PCI slot of my
> > motherboard and the conflict with the ata6 interrupt seems to be
> > solved. The silo over- flows are still there.
> > 
> > By the way: How should I set the BIOS parameters "PCPI 2.0 yes/no"
> > and"ACPI APIC yes/no"? Do they have anything to do with the PCI
> > interrupt behaviour?
> 
> I had to enable APIC to get my puc supported card to work.  W/o it the
> interrupts were shared and I received a ton of silo overflows and lost
> data on line.
> 
> so try the following in your kernel and rebuild
> 
> options COM_MULTIPORT
> options PUC_FASTINTR
> 
> device apic
> 
Thanks for the hint, this solves my problem. I now have a constant
char input flow rate of about 11000 chars/s at 115200 bps. This
makes an average interupt rate of 1400 ints/s, so each interrupt
service gets about 8 input chars of the silo. With a 16[45]50 silo
size of 16 chars this seems to be a reasonable rate. All the silo
overflow warnings disappeared.

Btw, "device apic" doesn't exist; did you mean "device acpi"?

Burkard

--
Burkard Meyendriesch
Stevern 2
D-48301 Nottuln