8.0-RC1: AMD CS5536 (Geode) USB 2.0 controller strange behavour

Eugene Grosbein eugen at kuzbass.ru
Mon Sep 28 17:29:54 UTC 2009


On Mon, Sep 28, 2009 at 08:49:21AM +0200, Hans Petter Selasky wrote:

> > > If the USB stack puts the new job into the schedule and the USB
> > > controller does not pick it up, it is not an USB stack problem ...
> >
> > If so, any workarounds possible?
> 
> None which I know about.

I've just found one. I noticed that USB controller here uses IRQ10
and shares it with NIC and FireWire. This system does not support IO-APIC.
I've disabled ACPI and NIC has moved to another IRQ,
USB and FireWire still share one IRQ but now there are no stalled transfers.
I get stable 16.2 megabyte/s writing speed to USB HDD.

Now I wonder if there is another way to assign distinct IRQ for USB,
BIOS Setup does not help.

Eugene Grosbein.


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