[patch 2.5] 2-pass PCI probing, i386 USB quirk

[Ivan Kokshaysky]

Untested, but it might work. Perhaps this needs to be chip specific (VIA?).

Ivan.

--- 2.5.55/arch/i386/pci/fixup.c	Thu Jan  9 07:04:19 2003
+++ linux/arch/i386/pci/fixup.c	Thu Jan  9 15:10:34 2003
@@ -187,6 +187,24 @@ static void __devinit pci_fixup_transpar
 		dev->transparent = 1;
 }
 
+/*
+ * On certain systems with legacy USB support, the USB controller does
+ * access the system memory while we boot, so disconnecting the host
+ * bridge (along with system memory) from PCI bus during the PCI window
+ * sizing causes immediate crash.
+ * To avoid this, clear the MASTER bit before we start probing the BARs.
+ */
+static void __devinit pci_fixup_usb_dma(struct pci_dev *dev)
+{
+	u16 cmd;
+
+	if ((dev->class >> 8) == PCI_CLASS_SERIAL_USB) {
+		pci_read_config_word(dev, PCI_COMMAND, &cmd);
+		pci_write_config_word(dev, PCI_COMMAND,
+				      cmd & ~PCI_COMMAND_MASTER);
+	}
+}
+
 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 +223,6 @@ 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_EARLY,	PCI_ANY_ID,		PCI_ANY_ID,			pci_fixup_usb_dma },
 	{ 0 }
 };