Re: Linux 2.6.17: IRQ handler mismatch in serial code?

Russell King
2006-06-19T19:44:17Z

On Mon, Jun 19, 2006 at 08:40:24PM +0100, Chris Rankin wrote:
> --- Russell King <rmk+lkml@arm.linux.org.uk> wrote:
> > This seems to be an invalid situation - you appear to have an _ISA_
> > NE2000 card using IRQ3, trying to share the same interrupt as a
> > serial port.
> >
> > ISA interrupts aren't sharable without additional hardware support
> > or specific software support in the Linux kernel interrupt
> > architecture.
>
> Hmm, I see what you mean. Except that I thought that I'd manually disabled the motherboard's
> serial device on IRQ 3, via the BIOS:
>
> Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing enabled
> serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
> pnp: Device 00:07 activated.
> 00:07: ttyS2 at I/O 0x3e8 (irq = 4) is a 16550A
> pnp: Device 00:08 activated.
> 00:08: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
>
> Does Linux reenable all motherboard devices, regardless?

Question for Adam Belay.

>From the messages above, ttyS1 was not accessible when we probed it
via the legacy ISA table, but was in the PnP table and became
accessible when it was activated via PnP.

--
Russell King
Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/
maintainer of: 2.6 Serial core