fdtdec: Add API to read pci bus-range property

Add fdtdec_get_pci_bus_range to read bus-range property
values.

Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/include/fdtdec.h b/include/fdtdec.h
index bc79389..152eb07 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -445,6 +445,19 @@
 			 u32 *bar);
 
 /**
+ * Look at the bus range property of a device node and return the pci bus
+ * range for this node.
+ * The property must hold one fdt_pci_addr with a length.
+ * @param blob		FDT blob
+ * @param node		node to examine
+ * @param res		the resource structure to return the bus range
+ * @return 0 if ok, negative on error
+ */
+
+int fdtdec_get_pci_bus_range(const void *blob, int node,
+			     struct fdt_resource *res);
+
+/**
  * Look up a 32-bit integer property in a node and return it. The property
  * must have at least 4 bytes of data. The value of the first cell is
  * returned.
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index 30a1c6a..d3b22ec 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -243,6 +243,22 @@
 
 	return 0;
 }
+
+int fdtdec_get_pci_bus_range(const void *blob, int node,
+			     struct fdt_resource *res)
+{
+	const u32 *values;
+	int len;
+
+	values = fdt_getprop(blob, node, "bus-range", &len);
+	if (!values || len < sizeof(*values) * 2)
+		return -EINVAL;
+
+	res->start = fdt32_to_cpu(*values++);
+	res->end = fdt32_to_cpu(*values);
+
+	return 0;
+}
 #endif
 
 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,