[realtek] rtl 8139 NIC set to wrong IRQ by Linux

Donald Becker becker@scyld.com
Mon, 21 Aug 2000 23:01:04 -0400 (EDT)


On Mon, 21 Aug 2000, James Palma wrote:

> I have a configuration problem that I hope is simple.  My SMC1211TX NIC, 
> which uses a RealTek 8139 chip, is being set to the wrong IRQ by Linux 
> during start-up.

Linux doesn't assign the IRQ.

Only the BIOS knows how to configure the INT-to-IRQ steering on the
motherboard.
Once this is done the IRQ line is written to a register on the PCI card.

The Linux driver reads this register to learn the IRQ.
  Note: Changing this register has no impact on the actual IRQ steering.

>  Instead of being set to IRQ 11, it is set to IRQ 0.  More 
> annoying, it sometimes is set to the right IRQ, and then the card 
> works...  I am running it 
> as a UMSDOS file system (the "BigSlak" distribution).

I'm guessing it's a PCI power management issue.  If you warm boot from
MS-Windows the card is left in ACPI D3 state.

You'll need the driver with pci-scan support to correct reset the power
state.

 http://www.scyld.com/network/rtl8139.html

> As you can see, all the PCI devices share IRQ 11.  Is this a problem?  As 
> far as I can tell, it shouldn't be.

Not a problem...


Donald Becker				becker@scyld.com
Scyld Computing Corporation		http://www.scyld.com
410 Severn Ave. Suite 210		Beowulf-II Cluster Distribution
Annapolis MD 21403