VIA PCI routing problem

From: Nick Piggin
Date: Thu Jul 28 2005 - 07:11:47 EST


Hi,

Sorry in taking so long to track this down. I just got motivated
today.

I have a VIA SMP system and somewhere between 2.6.12-rc3 and 2.6.12
the USB mouse started moving around really slowly. Anyway, it turns
out that the attached patch (against 2.6.13-rc3-git8) fixes the problem.

Let me know if any info is needed or if you would like me to test a
patch.

This is a regression versus 2.6.11 so it would be good to have a fix in
2.6.13.

Thanks,
Nick

--
SUSE Labs, Novell Inc.

Index: linux-2.6/arch/i386/pci/irq.c
===================================================================
--- linux-2.6.orig/arch/i386/pci/irq.c 2005-07-28 19:03:48.000000000 +1000
+++ linux-2.6/arch/i386/pci/irq.c 2005-07-28 21:58:52.000000000 +1000
@@ -1132,6 +1132,7 @@ static int pirq_enable_irq(struct pci_de
printk(KERN_WARNING "PCI: No IRQ known for interrupt pin %c of device %s.%s\n",
'A' + pin, pci_name(dev), msg);
}
+ pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq & 15);
return 0;
}

Index: linux-2.6/drivers/pci/quirks.c
===================================================================
--- linux-2.6.orig/drivers/pci/quirks.c 2005-07-28 21:41:56.000000000 +1000
+++ linux-2.6/drivers/pci/quirks.c 2005-07-28 21:59:35.000000000 +1000
@@ -499,6 +499,7 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_V
*/
static void quirk_via_irq(struct pci_dev *dev)
{
+#if 0
u8 irq, new_irq;

new_irq = dev->irq & 0xf;
@@ -509,6 +510,7 @@ static void quirk_via_irq(struct pci_dev
udelay(15); /* unknown if delay really needed */
pci_write_config_byte(dev, PCI_INTERRUPT_LINE, new_irq);
}
+#endif
}
DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_VIA, PCI_ANY_ID, quirk_via_irq);

Index: linux-2.6/drivers/acpi/pci_irq.c
===================================================================
--- linux-2.6.orig/drivers/acpi/pci_irq.c 2005-07-28 19:04:00.000000000 +1000
+++ linux-2.6/drivers/acpi/pci_irq.c 2005-07-28 21:58:14.000000000 +1000
@@ -444,6 +444,8 @@ acpi_pci_irq_enable (
}
}

+ pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq & 15);
+
dev->irq = acpi_register_gsi(irq, edge_level, active_high_low);

printk(KERN_INFO PREFIX "PCI Interrupt %s[%c] -> ",