of/address: merge of_iomap()

Merge common code between Microblaze and PowerPC.  This patch creates
new of_address.h and address.c files to containing address translation
and mapping routines.  First routine to be moved it of_iomap()

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Michal Simek <monstr@monstr.eu>
CC: Stephen Rothwell <sfr@canb.auug.org.au>
diff --git a/drivers/of/address.c b/drivers/of/address.c
new file mode 100644
index 0000000..258528d
--- /dev/null
+++ b/drivers/of/address.c
@@ -0,0 +1,22 @@
+
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/of_address.h>
+
+/**
+ * of_iomap - Maps the memory mapped IO for a given device_node
+ * @device:	the device whose io range will be mapped
+ * @index:	index of the io range
+ *
+ * Returns a pointer to the mapped memory
+ */
+void __iomem *of_iomap(struct device_node *np, int index)
+{
+	struct resource res;
+
+	if (of_address_to_resource(np, index, &res))
+		return NULL;
+
+	return ioremap(res.start, 1 + res.end - res.start);
+}
+EXPORT_SYMBOL(of_iomap);