fdt: Add fdtdec_get_uint64 to decode a 64-bit value from a property

It decodes a 64-bit value from a property that is at least 8 bytes long.

Signed-off-by: Che-Liang Chiou <clchiou@chromium.org>

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 15 insertions, 0 deletions

diff --git a/include/fdtdec.h b/include/fdtdec.h
index a37cf54a935..b5d7d2f54a2 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -182,6 +182,21 @@ s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
 		s32 default_val);
 
 /**
+ * Look up a 64-bit integer property in a node and return it. The property
+ * must have at least 8 bytes of data (2 cells). The first two cells are
+ * concatenated to form a 8 bytes value, where the first cell is top half and
+ * the second cell is bottom half.
+ *
+ * @param blob	FDT blob
+ * @param node	node to examine
+ * @param prop_name	name of property to find
+ * @param default_val	default value to return if the property is not found
+ * @return integer value, if found, or default_val if not
+ */
+uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
+		uint64_t default_val);
+
+/**
  * Checks whether a node is enabled.
  * This looks for a 'status' property. If this exists, then returns 1 if
  * the status is 'ok' and 0 otherwise. If there is no status property,