PCI: Support BAR sizes up to 8GB

This is needed for some of the Xeon Phi type systems.

[bhelgaas: added Nikhil, use ARRAY_SIZE() to connect with decl, folded in
Kevin's "order < 0" fix to ARRAY_SIZE() usage]
Signed-off-by: Nikhil P Rao <nikhil.rao@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 10 insertions, 5 deletions

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 138bdd6393be..9b3498c9b739 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -921,7 +921,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
 {
         struct pci_dev *dev;
         resource_size_t min_align, align, size, size0, size1;
-        resource_size_t aligns[12];     /* Alignments from 1Mb to 2Gb */
+        resource_size_t aligns[14];     /* Alignments from 1Mb to 8Gb */
         int order, max_order;
         struct resource *b_res = find_free_bus_resource(bus, type);
         unsigned int mem64_mask = 0;
@@ -957,10 +957,17 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
                                 continue;
                         }
 #endif
-                        /* For bridges size != alignment */
+                        /*
+                         * aligns[0] is for 1MB (since bridge memory
+                         * windows are always at least 1MB aligned), so
+                         * keep "order" from being negative for smaller
+                         * resources.
+                         */
                         align = pci_resource_alignment(dev, r);
                         order = __ffs(align) - 20;
-                        if (order > 11) {
+                        if (order < 0)
+                                order = 0;
+                        if (order >= ARRAY_SIZE(aligns)) {
                                 dev_warn(&dev->dev, "disabling BAR %d: %pR "
                                          "(bad alignment %#llx)\n", i, r,
                                          (unsigned long long) align);
@@ -968,8 +975,6 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
                                 continue;
                         }
                         size += r_size;
-                        if (order < 0)
-                                order = 0;
                         /* Exclude ranges with size > align from
                            calculation of the alignment. */
                         if (r_size == align)