1 files changed, 60 insertions, 21 deletions

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index fb506137aaee..1e808ca338f8 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -697,6 +697,38 @@ static resource_size_t calculate_memsize(resource_size_t size,
         return size;
 }
 
+resource_size_t __weak pcibios_window_alignment(struct pci_bus *bus,
+                                                unsigned long type)
+{
+        return 1;
+}
+
+#define PCI_P2P_DEFAULT_MEM_ALIGN       0x100000        /* 1MiB */
+#define PCI_P2P_DEFAULT_IO_ALIGN        0x1000          /* 4KiB */
+#define PCI_P2P_DEFAULT_IO_ALIGN_1K     0x400           /* 1KiB */
+
+static resource_size_t window_alignment(struct pci_bus *bus,
+                                        unsigned long type)
+{
+        resource_size_t align = 1, arch_align;
+
+        if (type & IORESOURCE_MEM)
+                align = PCI_P2P_DEFAULT_MEM_ALIGN;
+        else if (type & IORESOURCE_IO) {
+                /*
+                 * Per spec, I/O windows are 4K-aligned, but some
+                 * bridges have an extension to support 1K alignment.
+                 */
+                if (bus->self->io_window_1k)
+                        align = PCI_P2P_DEFAULT_IO_ALIGN_1K;
+                else
+                        align = PCI_P2P_DEFAULT_IO_ALIGN;
+        }
+
+        arch_align = pcibios_window_alignment(bus, type);
+        return max(align, arch_align);
+}
+
 /**
  * pbus_size_io() - size the io window of a given bus
  *
@@ -717,17 +749,12 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
         struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
         unsigned long size = 0, size0 = 0, size1 = 0;
         resource_size_t children_add_size = 0;
-        resource_size_t min_align = 4096, align;
+        resource_size_t min_align, io_align, align;
 
         if (!b_res)
                 return;
 
-        /*
-         * Per spec, I/O windows are 4K-aligned, but some bridges have an
-         * extension to support 1K alignment.
-         */
-        if (bus->self->io_window_1k)
-                min_align = 1024;
+        io_align = min_align = window_alignment(bus, IORESOURCE_IO);
         list_for_each_entry(dev, &bus->devices, bus_list) {
                 int i;
 
@@ -754,8 +781,8 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
                 }
         }
 
-        if (min_align > 4096)
-                min_align = 4096;
+        if (min_align > io_align)
+                min_align = io_align;
 
         size0 = calculate_iosize(size, min_size, size1,
                         resource_size(b_res), min_align);
@@ -785,6 +812,28 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
         }
 }
 
+static inline resource_size_t calculate_mem_align(resource_size_t *aligns,
+                                                  int max_order)
+{
+        resource_size_t align = 0;
+        resource_size_t min_align = 0;
+        int order;
+
+        for (order = 0; order <= max_order; order++) {
+                resource_size_t align1 = 1;
+
+                align1 <<= (order + 20);
+
+                if (!align)
+                        min_align = align1;
+                else if (ALIGN(align + min_align, min_align) < align1)
+                        min_align = align1 >> 1;
+                align += aligns[order];
+        }
+
+        return min_align;
+}
+
 /**
  * pbus_size_mem() - size the memory window of a given bus
  *
@@ -864,19 +913,9 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
                                 children_add_size += get_res_add_size(realloc_head, r);
                 }
         }
-        align = 0;
-        min_align = 0;
-        for (order = 0; order <= max_order; order++) {
-                resource_size_t align1 = 1;
 
-                align1 <<= (order + 20);
-
-                if (!align)
-                        min_align = align1;
-                else if (ALIGN(align + min_align, min_align) < align1)
-                        min_align = align1 >> 1;
-                align += aligns[order];
-        }
+        min_align = calculate_mem_align(aligns, max_order);
+        min_align = max(min_align, window_alignment(bus, b_res->flags & mask));
         size0 = calculate_memsize(size, min_size, 0, resource_size(b_res), min_align);
         if (children_add_size > add_size)
                 add_size = children_add_size;