irq conflict with any pcmcia nic

[Kevin Oberman]

> From: "Zhang Weiwu" <weiwuzhang at hotmail.com>
> Date: Fri, 17 Oct 2003 11:08:40 +0800
> Sender: owner-freebsd-mobile at freebsd.org
> 
> Hello. I have 4.9-RC2 running on my Thinkpad R30. Last month the built-in 
> NIC (EtherExpress) stopped working (it's another long story) so I begin to 
> use pcmcia NIC. 
> 
> The problem is that I tried two different NICs, both use ed and report 
> "device timeout". Tracking dmesg I found: (both cards show similiar dmesg)
> 
> pcic0 <02micro 6912 PCI-Cardbus Birdge> irq 6 at device 19.0 on pci0
> ed0 at port 0x300-0x31f irq 6 slot 0 on pccard0
> 
> This shows an irq conflict. But I am not able to assign another irq to 
> pcic, compiling a "device pcic0 at isa? irq 10" kernel havn't changed 
> anything, irq 6 still goes to pcic0.
> 
> Neither can I assign a different irq to the nic. The pccard.conf doesn't 
> have irq 6 in it (actually "irq 3 5 10"). I don't know why pccardd assign 
> irq 6 when it is not reserved in pccard.conf. 
> 
> Help really appreciated. Thank you.

This is a common point of confusion. As of 4.6(?) support for PCI
routing of PCMCIA cards was added and with it, the PCI capability to
share interrupts. As a result you can expect that any PCcard will (and
must) use the same IRQ as the PC-CardBus bridge uses. This is not a
conflict but normal behavior.

On my system I see:
> vmstat -i
interrupt                   total       rate
mux irq11                17398112         52
ata0 irq14               12700324         38
ata1 irq15                     38          0
pcm0 irq10                 811751          2
fdc0 irq6                       2          0
atkbd0 irq1                 82547          0
psm0 irq12                1790028          5
sio0 irq4                   35881          0
clk irq0                 33203802         99
rtc irq8                 42503604        128
Total                   108526089        326

The "mux" device is the shared PCI IRQ and covers any PCI devices that
choose to use it. In my case, the network interface, xl, is using this
shared IRQ and operating perfectly fine.

Unfortunately, I don't have any idea what your real problem with
PCMCIA cards might be.
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634