Re: usb wheel mouse, XF4.0

Hi all,

On  29 Nov, this message from Benjamin Herrenschmidt echoed through cyberspace:

quoted

In addition, yesterday I speculated that the dual IRQ 23 might help
explain why I was having 2.2.18preX boot problems with the aic7xxx.
This can't really be the case because one of the slot summary tests
was to remove the USB card (and all others). There was no difference,
so my boot issue remains a separate one with its odd workaround.

Ok, I found the problem, I think, with the interrupt. I'm still
investigating, but what it looks like is that the OF tree puts the
AAPL,interrupt property in the pci-bridge node, not in the sub-nodes.

I remember seeing this documented somewhere in the kernel sources, I
think.

Also, another 'shot in the dark': might we have a bug in the PCI-bridge
code, that (erronously) rotates interrupts? On Intel machines, the 4 PCI
interrupt lines are BIOS-wired to some IRQs, and are rotated one
position while passing to the next PCI slot. They are also, IIRC,
rotated by each PCI bridge. This _could_ make the USB card be configured
for the wrong interrupt, maybe the adjacent slot: SCSI controller....

Just a thought...

Michel

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