Re: Not enough IRQs for multiple PCMCIA cards

[Nils Faerber <nils-t93Ne7XHvje5bSeCtf/tX7NAH6kLmebB@public.gmane.org>]

On Sat, 10 May 2003 01:48:07 +0100
Chris Howells <chrish-puGfsi27rH1aa/9Udqfwiw@public.gmane.org> wrote:
> Hi,
Hi!

> I'm having huge problems trying to get enough IRQs for me to be able
> to use a PCMCIA modem (D-Link 560) and a Wifi card (Netgear MA401)
> simultaneously.

For the record:
	I have exactly the same problem.

[...]
> For example, if I plug my modem in, it gets assigned IRQ 7. If I
> remove it, and plug the Wifi card in, it gets assigned IRQ 7. If I put
> both in simultaneously, the last one to be inserted does not get an
> IRQ.
> 
> I have tried with ACPI enabled and with pci=noacpi.

> Regrettably, my BIOS (Award Asus L3800C BIOS) does not give me any
> control how IRQs are designed or PnP OS settings.

I have even the same machine :)

[...]
> Thanks for any ideas

OK.
It is quite important to know a litle more about your setup.
Why?
I have tried with several kernels, pcmcia packages and configurations.
Some worked, some not.
Do you use kernel pcmcia or the PCMCIA drivers from pcmcia-cs?
	I currently use kernel pcmcia which currently does not work with twi
cards.

Which PCMCIA (cardbus) chipset driver do you use?
	I strongly recommend to use the kernel yenta socket driver! This gives
best results with cardbus cards.

Some earlier kernel version with ACPI patch applied worked with
pci=noacpi but this seems to have almost no effect on more recent
kernels. I currently use 2.4.21-pre4 with ACPI 20030228.

Then there are some problems with certain PCMCIA drivers.
In theory they should be able to share the one assigned interrupt. The
serial_cs driver does so AFAIK. But many other drivers don't, like
ide_cs. So some combinations may work, some not.

This whole situation is, like you said, very unsatisfying :(
It is a real pain that there is no decent APIC in uniprocessor systems
in order to have more than those shitty 15 IRQs... it's a shame... x86
hardware is really crappy at times but there is not much of an
alternative especially for notebooks :( (Oh oh ... no flame war start
please!)

> Cheers, Chris Howells -- chris-NvB7AskkBIqIudiWw5vspbVCufUGDwFn@public.gmane.org, howells@kde.org
CU
  nils faerber

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