3 files changed, 63 insertions, 1 deletions

diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h
index 42ce570812c1..f7706d722b39 100644
--- a/arch/powerpc/include/asm/machdep.h
+++ b/arch/powerpc/include/asm/machdep.h
@@ -214,6 +214,9 @@ struct machdep_calls {
         /* Called after scan and before resource survey */
         void (*pcibios_fixup_phb)(struct pci_controller *hose);
 
+        /* Called during PCI resource reassignment */
+        resource_size_t (*pcibios_window_alignment)(struct pci_bus *, unsigned long type);
+
         /* Called to shutdown machine specific hardware not already controlled
          * by other drivers.
          */
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index 2aa04f29e1de..43fea543d686 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -99,6 +99,26 @@ void pcibios_free_controller(struct pci_controller *phb)
                 kfree(phb);
 }
 
+/*
+ * The function is used to return the minimal alignment
+ * for memory or I/O windows of the associated P2P bridge.
+ * By default, 4KiB alignment for I/O windows and 1MiB for
+ * memory windows.
+ */
+resource_size_t pcibios_window_alignment(struct pci_bus *bus,
+                                         unsigned long type)
+{
+        if (ppc_md.pcibios_window_alignment)
+                return ppc_md.pcibios_window_alignment(bus, type);
+
+        /*
+         * PCI core will figure out the default
+         * alignment: 4KiB for I/O and 1MiB for
+         * memory window.
+         */
+        return 1;
+}
+
 static resource_size_t pcibios_io_size(const struct pci_controller *hose)
 {
 #ifdef CONFIG_PPC64
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 9cda6a1ad0cf..0e7eccc0f88d 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -855,7 +855,7 @@ static void __devinit pnv_ioda_setup_PEs(struct pci_bus *bus)
                 if (pe == NULL)
                         continue;
                 /* Leaving the PCIe domain ... single PE# */
-                if (dev->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE)
+                if (pci_pcie_type(dev) == PCI_EXP_TYPE_PCI_BRIDGE)
                         pnv_ioda_setup_bus_PE(dev, pe);
                 else if (dev->subordinate)
                         pnv_ioda_setup_PEs(dev->subordinate);
@@ -1139,6 +1139,44 @@ static void __devinit pnv_pci_ioda_fixup_phb(struct pci_controller *hose)
         }
 }
 
+/*
+ * Returns the alignment for I/O or memory windows for P2P
+ * bridges. That actually depends on how PEs are segmented.
+ * For now, we return I/O or M32 segment size for PE sensitive
+ * P2P bridges. Otherwise, the default values (4KiB for I/O,
+ * 1MiB for memory) will be returned.
+ *
+ * The current PCI bus might be put into one PE, which was
+ * create against the parent PCI bridge. For that case, we
+ * needn't enlarge the alignment so that we can save some
+ * resources.
+ */
+static resource_size_t pnv_pci_window_alignment(struct pci_bus *bus,
+                                                unsigned long type)
+{
+        struct pci_dev *bridge;
+        struct pci_controller *hose = pci_bus_to_host(bus);
+        struct pnv_phb *phb = hose->private_data;
+        int num_pci_bridges = 0;
+
+        bridge = bus->self;
+        while (bridge) {
+                if (pci_pcie_type(bridge) == PCI_EXP_TYPE_PCI_BRIDGE) {
+                        num_pci_bridges++;
+                        if (num_pci_bridges >= 2)
+                                return 1;
+                }
+
+                bridge = bridge->bus->self;
+        }
+
+        /* We need support prefetchable memory window later */
+        if (type & IORESOURCE_MEM)
+                return phb->ioda.m32_segsize;
+
+        return phb->ioda.io_segsize;
+}
+
 /* Prevent enabling devices for which we couldn't properly
  * assign a PE
  */
@@ -1306,6 +1344,7 @@ void __init pnv_pci_init_ioda1_phb(struct device_node *np)
          */
         ppc_md.pcibios_fixup_phb = pnv_pci_ioda_fixup_phb;
         ppc_md.pcibios_enable_device_hook = pnv_pci_enable_device_hook;
+        ppc_md.pcibios_window_alignment = pnv_pci_window_alignment;
         pci_add_flags(PCI_PROBE_ONLY | PCI_REASSIGN_ALL_RSRC);
 
         /* Reset IODA tables to a clean state */