On Thu, Aug 21, 2014 at 09:26:52AM +1000, Anton Blanchard wrote:

From: Douglas Lehr <redacted>

The Crocodile chip occasionally comes up with 4k and 8k BAR sizes.
Due to an errata, 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.

This quirk will force Linux to allocate the resource as a full page,
which will avoid the overlap.

Cc: <redacted> 
Signed-off-by: Douglas Lehr <redacted>
Signed-off-by: Anton Blanchard <redacted>
Acked-by: Milton Miller <redacted>

Applied to pci/misc for v3.18, thanks!

I tweaked it to print the expanded resource, see below.

commit 86b6431a306ab5a5204c436a45a3337fb17efa21
Author: Douglas Lehr [off-list ref]
Date:   Thu Aug 21 09:26:52 2014 +1000

    PCI: Increase IBM ipr SAS Crocodile BARs to at least system page size
    
    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 [off-list ref]
    Signed-off-by: Anton Blanchard [off-list ref]
    Signed-off-by: Bjorn Helgaas [off-list ref]
    Acked-by: Milton Miller [off-list ref]
    CC: stable@vger.kernel.org

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 80c2d014283d..e73960311fb4 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c

@@ -24,6 +24,7 @@
 #include <linux/ioport.h>
 #include <linux/sched.h>
 #include <linux/ktime.h>
+#include <linux/mm.h>
 #include <asm/dma.h>	/* isa_dma_bridge_buggy */
 #include "pci.h"
 

@@ -287,6 +288,25 @@ static void 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",
+				 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.