Re: VIA KT400 + Kernel 2.6.12 + IO-APIC + uhci_hcd = IRQ trouble

From: Michel Bouissou
Date: Mon Jul 25 2005 - 17:30:59 EST

Le Lundi 25 Juillet 2005 22:44, Alan Stern a écrit :
> Now that's strange.  When you plug the high-speed device into the
> integrated ports, which IRQ counter changes?  Since nothing is using IRQ
> 21, it should be disabled and its counter should remain constant.  Does
> this mean the interrupts show up on IRQ 19 (used by ehci-hcd), or do they
> not show up at all (i.e., is the USB connection just being polled)?

I assume it's IRQ 19.

cat /proc/interrupts doesn't show IRQ21 at all when uhci isn't loaded.

IRQ 19 being shared with 4 IDE controllers that controls my hard drives,
that's hard to isolate interrupts counts due to USB activity from interrupts
counts due to disks activity...

Michel Bouissou <michel@xxxxxxxxxxxx> OpenPGP ID 0xDDE8AC6E
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