1 files changed, 67 insertions, 0 deletions

diff --git a/drivers/of/address.c b/drivers/of/address.c
index 9e69b4f0d204..3c4b2af51611 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -223,6 +223,73 @@ int of_pci_address_to_resource(struct device_node *dev, int bar,
         return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
 }
 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
+
+int of_pci_range_parser_init(struct of_pci_range_parser *parser,
+                                struct device_node *node)
+{
+        const int na = 3, ns = 2;
+        int rlen;
+
+        parser->node = node;
+        parser->pna = of_n_addr_cells(node);
+        parser->np = parser->pna + na + ns;
+
+        parser->range = of_get_property(node, "ranges", &rlen);
+        if (parser->range == NULL)
+                return -ENOENT;
+
+        parser->end = parser->range + rlen / sizeof(__be32);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
+
+struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
+                                                struct of_pci_range *range)
+{
+        const int na = 3, ns = 2;
+
+        if (!range)
+                return NULL;
+
+        if (!parser->range || parser->range + parser->np > parser->end)
+                return NULL;
+
+        range->pci_space = parser->range[0];
+        range->flags = of_bus_pci_get_flags(parser->range);
+        range->pci_addr = of_read_number(parser->range + 1, ns);
+        range->cpu_addr = of_translate_address(parser->node,
+                                parser->range + na);
+        range->size = of_read_number(parser->range + parser->pna + na, ns);
+
+        parser->range += parser->np;
+
+        /* Now consume following elements while they are contiguous */
+        while (parser->range + parser->np <= parser->end) {
+                u32 flags, pci_space;
+                u64 pci_addr, cpu_addr, size;
+
+                pci_space = be32_to_cpup(parser->range);
+                flags = of_bus_pci_get_flags(parser->range);
+                pci_addr = of_read_number(parser->range + 1, ns);
+                cpu_addr = of_translate_address(parser->node,
+                                parser->range + na);
+                size = of_read_number(parser->range + parser->pna + na, ns);
+
+                if (flags != range->flags)
+                        break;
+                if (pci_addr != range->pci_addr + range->size ||
+                    cpu_addr != range->cpu_addr + range->size)
+                        break;
+
+                range->size += size;
+                parser->range += parser->np;
+        }
+
+        return range;
+}
+EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
+
 #endif /* CONFIG_PCI */
 
 /*