2000-11-18 16:04:38

by Marc Lehmann

Subject: reordering pci interrupts?

I have a motherboard with a broken bios that is unable to set interrupts
correctly, i.e. it initializes the devices corerctly but swaps the
interrupts for slot1/slot3 and slot2/slot4.

Now, is there a way to forcefully re-order the pci-interrupts? I do not
have an io-apic (thus no pirq=xxx), and I tried to poke the interrupt
values directly into /proc/bus/pic/*/*, but the kernel has it's own idea.

Thanks a lot for any info (I guess I'll just patch the kernel).

--
-----==- |
----==-- _ |
---==---(_)__ __ ____ __ Marc Lehmann +--
--==---/ / _ \/ // /\ \/ / [email protected] |e|
-=====/_/_//_/\_,_/ /_/\_\ XX11-RIPE --+
The choice of a GNU generation |
|

2000-11-19 19:52:45

by Martin Mares

Subject: Re: reordering pci interrupts?

Hello!

> I have a motherboard with a broken bios that is unable to set interrupts
> correctly, i.e. it initializes the devices corerctly but swaps the
> interrupts for slot1/slot3 and slot2/slot4.
>
> Now, is there a way to forcefully re-order the pci-interrupts? I do not
> have an io-apic (thus no pirq=xxx), and I tried to poke the interrupt
> values directly into /proc/bus/pic/*/*, but the kernel has it's own idea.
>
> Thanks a lot for any info (I guess I'll just patch the kernel).

Please try this patch and boot with "pci=autoirq" on the kernel command line.

Have a nice fortnight
--
Martin `MJ' Mares <[email protected]> <[email protected]> http://atrey.karlin.mff.cuni.cz/~mj/
"veni, vidi, nuclei deceiri - I came, I saw, I core dumped"


--- arch/i386/kernel/pci-pc.c.mj Sun Nov 19 20:18:14 2000
+++ arch/i386/kernel/pci-pc.c Sun Nov 19 20:18:14 2000
@@ -1035,6 +1035,9 @@
} else if (!strncmp(str, "lastbus=", 8)) {
pcibios_last_bus = simple_strtol(str+8, NULL, 0);
return NULL;
+ } else if (!strcmp(str, "autoirq")) {
+ pci_probe |= PCI_AUTOIRQ;
+ return NULL;
}
return str;
}
--- arch/i386/kernel/pci-i386.h.mj Sun Nov 19 20:18:32 2000
+++ arch/i386/kernel/pci-i386.h Sun Nov 19 20:18:32 2000
@@ -18,6 +18,7 @@
#define PCI_NO_SORT 0x100
#define PCI_BIOS_SORT 0x200
#define PCI_NO_CHECKS 0x400
+#define PCI_AUTOIRQ 0x800
#define PCI_ASSIGN_ROMS 0x1000
#define PCI_BIOS_IRQ_SCAN 0x2000

--- arch/i386/kernel/pci-irq.c.mj Sun Nov 19 20:18:50 2000
+++ arch/i386/kernel/pci-irq.c Sun Nov 19 20:18:50 2000
@@ -487,7 +487,7 @@
* If the BIOS has set an out of range IRQ number, just ignore it.
* Also keep track of which IRQ's are already in use.
*/
- if (dev->irq >= 16) {
+ if (dev->irq >= 16 || (pci_probe & PCI_AUTOIRQ)) {
DBG("%s: ignoring bogus IRQ %d\n", dev->slot_name, dev->irq);
dev->irq = 0;
}