[x86] fix lockups with APIC support on nForce2

Add PCI quirk to disable Halt Disconnect and Stop Grant Disconnect
(based on athcool program by Osamu Kayasono).

Spotted by Prakash K. Cheemplavam <prakashpublic@gmx.de>
and Mathieu <cheuche+lkml@free.fr>.

 arch/i386/pci/fixup.c |   17 +++++++++++++++++
 1 files changed, 17 insertions(+)

diff -puN arch/i386/pci/fixup.c~nforce2-disconnect-quirk arch/i386/pci/fixup.c
--- linux-2.6.0-test11/arch/i386/pci/fixup.c~nforce2-disconnect-quirk	2003-12-08 00:09:56.480294672 +0100
+++ linux-2.6.0-test11-root/arch/i386/pci/fixup.c	2003-12-08 00:09:56.484294064 +0100
@@ -187,6 +187,22 @@ static void __devinit pci_fixup_transpar
 		dev->transparent = 1;
 }
 
+/*
+ * Halt Disconnect and Stop Grant Disconnect (bit 4 at offset 0x6F)
+ * must be disabled when APIC is used (or lockups will happen).
+ */
+static void __devinit pci_fixup_nforce2_disconnect(struct pci_dev *d)
+{
+	u8 t;
+
+	pci_read_config_byte(d, 0x6F, &t);
+	if (t & 0x10) {
+		printk(KERN_INFO "PCI: disabling nForce2 Halt Disconnect"
+				 " and Stop Grant Disconnect\n");
+		pci_write_config_byte(d, 0x6F, (t & 0xef));
+	}
+}
+
 struct pci_fixup pcibios_fixups[] = {
 	{ PCI_FIXUP_HEADER,	PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_82451NX,	pci_fixup_i450nx },
 	{ PCI_FIXUP_HEADER,	PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_82454GX,	pci_fixup_i450gx },
@@ -205,5 +221,6 @@ struct pci_fixup pcibios_fixups[] = {
 	{ PCI_FIXUP_HEADER,	PCI_VENDOR_ID_VIA,	PCI_DEVICE_ID_VIA_8367_0,	pci_fixup_via_northbridge_bug },
 	{ PCI_FIXUP_HEADER,	PCI_VENDOR_ID_NCR,	PCI_DEVICE_ID_NCR_53C810,	pci_fixup_ncr53c810 },
 	{ PCI_FIXUP_HEADER,	PCI_VENDOR_ID_INTEL,	PCI_ANY_ID,			pci_fixup_transparent_bridge },
+	{ PCI_FIXUP_HEADER,	PCI_VENDOR_ID_NVIDIA,	PCI_DEVICE_ID_NVIDIA_NFORCE2,	pci_fixup_nforce2_disconnect },
 	{ 0 }
 };

_