[tulip] Tulip IRQ problems on FIC / Gericom laptops solved

Arndt Schoenewald abs@src88238x993.mc.schoenewald.de
Thu Apr 11 00:23:06 2002

Hi all,

there were a couple of postings during the last few months from people
trying to get the builtin Accton EN2242 network card of their Gericom
(1st Supersonic M6-T, Supersonic GPRS, Supersonic2) or FIC (A360, A380)
laptops to work. (The same problems were observed by people who owned
other OEM versions of this laptop, such as the Medion MD 9703, which are
equipped with a Realtek 8139 chip.)

The symptoms were that the NIC either did not get an IRQ assigned at all,
or (with an ACPI kernel patch) it would get an IRQ, but transmitting and
receiving packets would still fail, with driver error messages like:

    NETDEV WATCHDOG: eth0: transmit timed out
    eth0: Transmit timed out, status fc67c017, CSR12 00000000, resetting...

Well, I have the pleasure to announce that these problems are finally
resolved in the latest ACPI kernel patch acpi-20020404, which can now
be obtained from http://sourceforge.net/projects/acpi/ for the kernel
versions 2.4.18 and 2.5.7.

The problems were not related to the tulip driver, they were caused by 
improper IRQ activation.

Best regards,

Q: Why doesn't the Accton EN2242 network card get an IRQ with stock Linux

A: These laptops totally rely on ACPI for configuration (the BIOS does
   not have a valid PCI IRQ routing table), and the ACPI implementation
   of current standard Linux kernels is not fully functional yet.

Q: Why did it work with the acpi-20011218 kernel patch (plus updates),
   but not with later versions?

A: Patch acpi-20011218 did not yet include IRQ assignment; this feature
   was contributed by Kai Germaschewski through of a patch posted to the
   ACPI list in January 2002. With these patches the laptops worked fine,
   but unfortunately a subtile aspect of Kai's patch got lost during its
   integration into the ACPI mainline (the call to eisa_set_level_irq()).
   Many thanks to Dominik Brodowski for tracking this problem down and
   fixing it!

 /////    Quelltext AG -- Professional Software Services
//   //   Arndt Schönewald <arndt@quelltext.com>, CEO
//   //   Ostenhellweg 31, 44135 Dortmund, Germany
//  \\/   Tel +49 231 9503750, Fax +49 231 9503751
 ////\\   Web http://quelltext.com