5 files changed, 37 insertions, 15 deletions

diff --git a/Documentation/devicetree/bindings/pci/pci.txt b/Documentation/devicetree/bindings/pci/pci.txt
index 41aeed38926d..f8fbe9af7b2f 100644
--- a/Documentation/devicetree/bindings/pci/pci.txt
+++ b/Documentation/devicetree/bindings/pci/pci.txt
@@ -7,3 +7,14 @@ And for the interrupt mapping part:
 
 Open Firmware Recommended Practice: Interrupt Mapping
 http://www.openfirmware.org/1275/practice/imap/imap0_9d.pdf
+
+Additionally to the properties specified in the above standards a host bridge
+driver implementation may support the following properties:
+
+- linux,pci-domain:
+   If present this property assigns a fixed PCI domain number to a host bridge,
+   otherwise an unstable (across boots) unique number will be assigned.
+   It is required to either not set this property at all or set it for all
+   host bridges in the system, otherwise potentially conflicting domain numbers
+   may be assigned to root buses behind different host bridges.  The domain
+   number for each host bridge in the system must be unique.
diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index d292d7cb3417..49dd766852ba 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -444,7 +444,7 @@ static inline int pcie_cap_version(const struct pci_dev *dev)
         return pcie_caps_reg(dev) & PCI_EXP_FLAGS_VERS;
 }
 
-static inline bool pcie_cap_has_lnkctl(const struct pci_dev *dev)
+bool pcie_cap_has_lnkctl(const struct pci_dev *dev)
 {
         int type = pci_pcie_type(dev);
 
diff --git a/drivers/pci/host/pci-xgene.c b/drivers/pci/host/pci-xgene.c
index 9ecabfa8c634..2988fe136c1e 100644
--- a/drivers/pci/host/pci-xgene.c
+++ b/drivers/pci/host/pci-xgene.c
@@ -631,10 +631,15 @@ static int xgene_pcie_probe_bridge(struct platform_device *pdev)
         if (ret)
                 return ret;
 
-        bus = pci_scan_root_bus(&pdev->dev, 0, &xgene_pcie_ops, port, &res);
+        bus = pci_create_root_bus(&pdev->dev, 0,
+                                        &xgene_pcie_ops, port, &res);
         if (!bus)
                 return -ENOMEM;
 
+        pci_scan_child_bus(bus);
+        pci_assign_unassigned_bus_resources(bus);
+        pci_bus_add_devices(bus);
+
         platform_set_drvdata(pdev, port);
         return 0;
 }
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 0601890db22d..4a3902d8e6fe 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -6,6 +6,8 @@
 
 extern const unsigned char pcie_link_speed[];
 
+bool pcie_cap_has_lnkctl(const struct pci_dev *dev);
+
 /* Functions internal to the PCI core code */
 
 int pci_create_sysfs_dev_files(struct pci_dev *pdev);
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 5ed99309c758..c8ca98c2b480 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -407,15 +407,16 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child)
 {
         struct pci_dev *dev = child->self;
         u16 mem_base_lo, mem_limit_lo;
-        unsigned long base, limit;
+        u64 base64, limit64;
+        dma_addr_t base, limit;
         struct pci_bus_region region;
         struct resource *res;
 
         res = child->resource[2];
         pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
         pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
-        base = ((unsigned long) mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
-        limit = ((unsigned long) mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
+        base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
+        limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
 
         if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
                 u32 mem_base_hi, mem_limit_hi;
@@ -429,17 +430,20 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child)
                  * this, just assume they are not being used.
                  */
                 if (mem_base_hi <= mem_limit_hi) {
-#if BITS_PER_LONG == 64
-                        base |= ((unsigned long) mem_base_hi) << 32;
-                        limit |= ((unsigned long) mem_limit_hi) << 32;
-#else
-                        if (mem_base_hi || mem_limit_hi) {
-                                dev_err(&dev->dev, "can't handle 64-bit address space for bridge\n");
-                                return;
-                        }
-#endif
+                        base64 |= (u64) mem_base_hi << 32;
+                        limit64 |= (u64) mem_limit_hi << 32;
                 }
         }
+
+        base = (dma_addr_t) base64;
+        limit = (dma_addr_t) limit64;
+
+        if (base != base64) {
+                dev_err(&dev->dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
+                        (unsigned long long) base64);
+                return;
+        }
+
         if (base <= limit) {
                 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
                                          IORESOURCE_MEM | IORESOURCE_PREFETCH;
@@ -1323,7 +1327,7 @@ static void program_hpp_type2(struct pci_dev *dev, struct hpp_type2 *hpp)
                         ~hpp->pci_exp_devctl_and, hpp->pci_exp_devctl_or);
 
         /* Initialize Link Control Register */
-        if (dev->subordinate)
+        if (pcie_cap_has_lnkctl(dev))
                 pcie_capability_clear_and_set_word(dev, PCI_EXP_LNKCTL,
                         ~hpp->pci_exp_lnkctl_and, hpp->pci_exp_lnkctl_or);