PCI SCSI interrupt clash

PCI SCSI interrupt clash

[Glenn Geers]

Hi,
	I check the kernel archive and found reference to the PCI interrupt clash 
between the 2940 (aic7xxx) and other cards. I also have the problem and it 
can lock up my entire machine.
The problem really rears its head when I  overclock my box (BX400 dual PIII 
450 MHZ) by as little as 10% (504 MHz, 112 MHZ bus). Both my soundblaster 
live and my onboard AIC7891 are assigned IRQ 19. My PCI slots are full 
(ethernet, 1394 card, soundblaster live, tv card, and Matrox G400). I 
enclose the win2k interrupt allocation for your perusal and comment (it's 
weird!)

Current kernel version is 2.4.17 but the problem has been evident since 
2.4.5 (at least). The 2.2 series does not exhibit the problem.

System Information report written at: 08/01/2002 08:44:11 PM
[IRQs]

IRQ Number	Device
5	Sound Blaster 16 or AWE32 or compatible (WDM)
128	Matrox Millennium G400 DualHead MAX
14	Primary IDE Channel
15	Secondary IDE Channel
11	Intel 82371AB/EB PCI to USB Universal Host Controller
36	Adaptec AHA-2940U2/U2W PCI SCSI Controller
52	Realtek RTL8139/810X Family PCI Fast Ethernet NIC
56	Hauppauge Win/TV 878/9 VFW Video Driver
56	Hauppauge Win/TV 878/9 VFW Audio Driver
60	Creative SB Live! Value (WDM)
64	Texas Instruments OHCI Compliant IEEE 1394 Host Controller
1	PC/AT Enhanced PS/2 Keyboard (101/102-Key)
4	Communications Port (COM1)
3	Communications Port (COM2)
6	Standard floppy disk controller
8	System CMOS/real time clock
13	Numeric data processor
12	Other Logitech Mouse PS/2

I hope someone can shed some light on the very high (>20) interrupt 
numbers. I'd really like and will help to get to the bottom of the problem.

Regards,
	Glenn

Re: PCI SCSI interrupt clash

[Reid Hekman]

On Tue, 2002-01-08 at 03:46, Glenn Geers wrote:
> enclose the win2k interrupt allocation for your perusal and comment (it's 
> weird!)
...
> System Information report written at: 08/01/2002 08:44:11 PM
> [IRQs]
> 
> IRQ Number    Device
> 5     Sound Blaster 16 or AWE32 or compatible (WDM)
> 128   Matrox Millennium G400 DualHead MAX
> 14    Primary IDE Channel
> 15    Secondary IDE Channel
> 11    Intel 82371AB/EB PCI to USB Universal Host Controller
> 36    Adaptec AHA-2940U2/U2W PCI SCSI Controller
> 52    Realtek RTL8139/810X Family PCI Fast Ethernet NIC
> 56    Hauppauge Win/TV 878/9 VFW Video Driver
> 56    Hauppauge Win/TV 878/9 VFW Audio Driver
> 60    Creative SB Live! Value (WDM)
> 64    Texas Instruments OHCI Compliant IEEE 1394 Host Controller
> 1     PC/AT Enhanced PS/2 Keyboard (101/102-Key)
> 4     Communications Port (COM1)
> 3     Communications Port (COM2)
> 6     Standard floppy disk controller
> 8     System CMOS/real time clock
> 13    Numeric data processor
> 12    Other Logitech Mouse PS/2
> 
> I hope someone can shed some light on the very high (>20) interrupt 
> numbers. I'd really like and will help to get to the bottom of the problem.

Win2k with the ACPI HAL will reroute IRQ's to 256 "virtual" IRQ's, hence
the high numbers.

What happens if you twiddle ACPI/PnP OS in the BIOS?

And do you really expect a PCI bus overclocked past 37MHz to survive
with 5 PCI cards? You get 40 lashes with a wet noodle >:-(

Regards,
Reid