Solved Interrupt Problem with PGC-GR290K

I'm reporting on the problem and it's solution in case this might help 
others.  Earlier I had sent a long message describing the interrupt 
problems.  If you are interested in the specific details see the message 
to this list with subject, "Interrupt problem with PCG-GR290K", dated 
08/11/2003.

To review the problem: the machine is a Sony Vaio PGC-GR290K. The 
ohci1394 module wasn't loading (i.e., 'modprobe ohci1394' failed).  The 
problem was that PCI wasn't mapping interrupts for the IEEE 1394 device 
(as well as several other devices - modem, one USB port, etc.).

I got into the PCI code and was a bit dismayed at the ad hoc methods 
used to map interrupts.  However, the most current ACPI patch does 
wonders for interrupt mapping and handling.

I had tried building several different kernels, some with code from 
RedHat, some from kernel.org.  The RedHat kernels were a problem because 
patches from other places (e.g., linux1394.org, and 
sourceforge.net/projects/acpi couldn't be applied because of RedHat 
changes.  I tried an Alan Cox 2.5.65 kernel from kernel.org, but there 
were many problems just building the kernel.  The module building and 
management code has changed in 2.5 which required changing some of the 
module utilities on my machine.  After much struggle, I finally got the 
2.5.65 kernel to build and load, but the 2.5.65 PCI and ACPI didn't fix 
any problems.  That was probably because I didn't turn of the APM code 
in xconfig.  When APM is running, ACPI exits.  Didn't learn that till 
much later.  Sigh.

Earlier this week, I tried building the 2.4.20-19.7 kernel from RedHat. 
  Still no luck.

Finally, I built the 2.4.21 kernel from kernel.org.  Here's where I 
learned about ACPI, APM, and APIC (don't know if APIC figures as part of 
the solution, but it had some interesting things to say in dmesg which 
I'll relate later).

Turned off APM in xconfig which allowed ACPI to run.  Still no luck.

Here's the important stuff ....

I applied the acpi-20030619-2.4.21 patch from 
soruceforge.net/projects/apci.  Now ACPI discovered the interrupts for 
the modem, third USB port, and the Firewire port and mapped them to IRQ 
9 (along with a lotta other stuff).

Now the following works just fine:

modprobe ieee1394
modprobe ohci1394
modprobe sbp2

The devices still don't show up in /proc/scsi/scsi, but I ran 
'rescan-scsi-bus.sh' (http://linux1394.org/sbp2.html) and the Firewire 
devices showed up (a Maxtor disk and a Sony DVD R/RW drive).

'mount -t vfat /dev/sdb1 /mnt/tmp' mounted the Maxtor and
'mount -t iso9660 /dev/scd1 /mnt/tmp2' mounted the DVD drive.

Copied my home directory, nearly 8 GB, to the Maxtor with no apparent 
difficulties (no complaints in /var/log/messages, anyway) - the data 
seems to be all there.  Was able to read a CD from the DVD drive. 
Haven't tried writing to it yet.

PS about APIC.  When it came up it said that the APIC had been disabled 
by the BIOS (now why would it do that?), and APIC had re-enabled it. 
Interesting.

Regards,
Roy