PCI: Increase IBM ipr SAS Crocodile BARs to at least system page size

commit 9fe373f9 upstream.

The Crocodile chip occasionally comes up with 4k and 8k BAR sizes.  Due to
an erratum, setting the SR-IOV page size causes the physical function BARs
to expand to the system page size.  Since ppc64 uses 64k pages, when Linux
tries to assign the smaller resource sizes to the now 64k BARs the address
will be truncated and the BARs will overlap.

Force Linux to allocate the resource as a full page, which avoids the
overlap.

[bhelgaas: print expanded resource, too]
Signed-off-by: Douglas Lehr <dllehr@us.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Milton Miller <miltonm@us.ibm.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/pci/quirks.c

@@ -26,6 +26,7 @@
 #include <linux/dmi.h>
 #include <linux/pci-aspm.h>
 #include <linux/ioport.h>
+#include <linux/mm.h>
 #include <asm/dma.h>	/* isa_dma_bridge_buggy */
 #include "pci.h"
 
@@ -352,6 +353,25 @@ static void __devinit quirk_citrine(struct pci_dev *dev)
 }
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_IBM,	PCI_DEVICE_ID_IBM_CITRINE,	quirk_citrine);
 
+/*  On IBM Crocodile ipr SAS adapters, expand BAR to system page size */
+static void quirk_extend_bar_to_page(struct pci_dev *dev)
+{
+	int i;
+
+	for (i = 0; i < PCI_STD_RESOURCE_END; i++) {
+		struct resource *r = &dev->resource[i];
+
+		if (r->flags & IORESOURCE_MEM && resource_size(r) < PAGE_SIZE) {
+			r->end = PAGE_SIZE - 1;
+			r->start = 0;
+			r->flags |= IORESOURCE_UNSET;
+			dev_info(&dev->dev, "expanded BAR %d to page size: %pR\n",
+				 i, r);
+		}
+	}
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_IBM, 0x034a, quirk_extend_bar_to_page);
+
 /*
  *  S3 868 and 968 chips report region size equal to 32M, but they decode 64M.
  *  If it's needed, re-allocate the region.