IRQ problem with VIA chipset on Presario 700

[smeets_marc]

Posting here is kinda my last hope before I switch this machine back to Windows. I have been battling with it for about 2 months now, and basicly I just want my laptop to connected to my network on the go. The battle has been so hard that I'm almost on the point that the OS doesn't make any difference anymore...although I truly and deeply hate Windows. This issue is really making me "aaargh". Any help is welcome!

The laptop is a Compaq presario 700 (723EA to be more specific). It has a
1.1GHz duron cpu
VIA VT82C686B southbridge
integrated AC97 Audio controller
Texas Instruments PCI1410 PC Card Controller with 1 slot

That southbridge has a bug and VIA has admitted it but this has been taking care of in the Linux kernel (bug has been around for quite some time now) This laptop has no problems running Linux accoring to the many succes storys on internet. Clearly nobody has ever tryed to insert a 3Com 3CRWE154G72 wlan card. This wlan card has the prism chip, which is supported. I even saw a driver for it in gentoo-dev-sources 2.6.3. On the prism54.org site it is clearl that the card is one of the best supported cards. The card itself is working properly in other laptop.

When I insert the card it gets recognized well and the prism driver gets loaded. After that, hotplug gets called, the firmware should be loaded and the the card should get a soft reset. I gets stuck right there. The reset failes. I have been going through the prism code and updated the hotplug package and narrowed the problem down to a "assuming someone elsed called the irq". That error is generated in the prism code at this point which tells me that there is a bus problem. The prism code checks if the device is on a shared irq line (which it is) and whether it is in sleep mode, which it isn't because the device isn't even started yet.

cat /proc/interrupts tells me that on IRQ 11 (the irq of the card bus and the pc card) are the only one on that irq. If the onboard realtek gets configurerd, it also operates on IRQ11. Going through the messages in dmesg telles me that there is a "IRQ routing conflict" between the pc card controller and the integrated sound card. The sound card wants IRQ 11 but it gets IRQ 5. Even if I have completely no kernel support or modules loaded for the soundcard. The sound card is operating just fine even with that IRQ routing conflict, but the wlan card not. I get these exact same errors in 2.4.25 and 2.6.3.

The VIA southbridge bug is beeing work around according to this kernel message
Applying VIA Southbridge workaround
PCI: Disabling Via external APIC routing

What that apic does, I don't know. To be honest I don't know if apic is a good thing or a bad thing. I tryed with apic support and without but it doesn't make a difference.
Reading on internet I see many people suggest turning off acpi. I truned it off, but that also doesn't make a difference.

From where I stand, it looks like the souncard devices want irq 11 that bad it just takes it. Although /proc/interrupts tells me the sound device hasn't even got a irq yet (because no modules is loaded) I still get a irq conflict on irq 11.
The laptop's BIOS is the worst I have ever seen. You can adjust the time and the boot order and that's it. No BIOS update available. No more comaq for me, but I still want Linux on this one.

Forcing the card with ifconfig is useless beacuase ifconfig doesn't even get a right mac address from the device (00:00:00 etc is not right)

I simply don't know what to do anymore. I have tryed about everything and have no options left. The $%&^@ just won't work. Any help, ideas or suggestions is welcome!!!

[smeets_marc]

Nobody has a hint or an idea?

[cliffrowley]

Having the same problem on an IBM T40. Did you get any further? I'm still poking around, but no luck so far