Re: Strange EHCI/OHCI IRQ and other PCI errors on boot with 2.6.32(which 2.6.26 did not see) on Geode LX/CS5536.

From: Lennart Sorensen
Date: Wed Jan 20 2010 - 15:01:38 EST

On Wed, Jan 20, 2010 at 02:42:01PM -0500, Lennart Sorensen wrote:
> On Wed, Jan 20, 2010 at 11:37:07AM -0500, Alan Stern wrote:
> > It's true that the USB controllers appear to be the only devices using
> > IRQ 5. But your startup log shows that only two of the three
> > controllers have an associated driver. Maybe the third controller is
> > generating the unwanted interrupts?
> Could be. But I never saw the problem with 2.6.26. That's puzzling me.
> Now I think the 3rd controller may be a client mode interface on the
> Geode LX, which I certainly don't use if it has such a thing.
> I know what EHCI and OHCI mean. I don't know what UDC is. I see mention
> of UDC under USB gadget support. I will try enabling that driver and
> see what it does.

So the only difference is that now it happens 3 times instead of 2.
Once each for ehci, ohci and amd5536udc.

Interestingly the number of interrupts listed in /proc/interrupts is
exactly 300000.

0: 62675 XT-PIC-XT timer
2: 0 XT-PIC-XT cascade
3: 7 XT-PIC-XT
4: 772 XT-PIC-XT serial
5: 300000 XT-PIC-XT ehci_hcd:usb1, ohci_hcd:usb2, amd5536udc
7: 1 XT-PIC-XT
8: 2 XT-PIC-XT rtc0
10: 1 XT-PIC-XT geode-mfgpt, eth2
11: 68 XT-PIC-XT eth1
14: 2237 XT-PIC-XT pata_cs5536
NMI: 0 Non-maskable interrupts
LOC: 0 Local timer interrupts
SPU: 0 Spurious interrupts
PMI: 0 Performance monitoring interrupts
PND: 0 Performance pending work
ERR: 1
MIS: 0

That's a lot of interrupts for a system that was just booted.

Hmm, I just tried booting 2.6.26 again, and now it too is failing.
I think my box just broke. Aghhh!

So I think that means there is no problem, I just have to go get
another box. I hate hardware problems. :)

Len Sorensen
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