Fix bogus PCI quirk for e100

Linas reported me that some machines were crashing at boot in
quirk_e100_interrupt. It appears that this quirk is doing an ioremap
directly on a PCI BAR value, which isn't legal and will cause all sorts
of bad things to happen on architectures where PCI BARs don't directly
match processor bus addresses.

This fixes it by using the proper PCI resources instead which is possible
since the quirk has been moved by a previous commit to happen late enough
for that.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/pci/quirks.c

@@ -1444,7 +1444,6 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_NETMOS, PCI_ANY_ID, quirk_netmos);
 static void __devinit quirk_e100_interrupt(struct pci_dev *dev)
 {
 	u16 command;
-	u32 bar;
 	u8 __iomem *csr;
 	u8 cmd_hi;
 
@@ -1476,12 +1475,12 @@ static void __devinit quirk_e100_interrupt(struct pci_dev *dev)
 	 * re-enable them when it's ready.
 	 */
 	pci_read_config_word(dev, PCI_COMMAND, &command);
-	pci_read_config_dword(dev, PCI_BASE_ADDRESS_0, &bar);
 
-	if (!(command & PCI_COMMAND_MEMORY) || !bar)
+	if (!(command & PCI_COMMAND_MEMORY) || !pci_resource_start(dev, 0))
 		return;
 
-	csr = ioremap(bar, 8);
+	/* Convert from PCI bus to resource space.  */
+	csr = ioremap(pci_resource_start(dev, 0), 8);
 	if (!csr) {
 		printk(KERN_WARNING "PCI: Can't map %s e100 registers\n",
 			pci_name(dev));