dm: core: Add a place to put extra device-tree reading functions

Some functions deal with structured data rather than simple data types.
It makes sense to have these in their own file. For now this just has a
function to read a flashmap entry. Move the data types also.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/dm/of_extra.h b/include/dm/of_extra.h
new file mode 100644
index 0000000..01b6ebe
--- /dev/null
+++ b/include/dm/of_extra.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2017 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _DM_OF_EXTRA_H
+#define _DM_OF_EXTRA_H
+
+#include <dm/ofnode.h>
+
+enum fmap_compress_t {
+	FMAP_COMPRESS_NONE,
+	FMAP_COMPRESS_LZO,
+};
+
+enum fmap_hash_t {
+	FMAP_HASH_NONE,
+	FMAP_HASH_SHA1,
+	FMAP_HASH_SHA256,
+};
+
+/* A flash map entry, containing an offset and length */
+struct fmap_entry {
+	uint32_t offset;
+	uint32_t length;
+	uint32_t used;			/* Number of bytes used in region */
+	enum fmap_compress_t compress_algo;	/* Compression type */
+	enum fmap_hash_t hash_algo;		/* Hash algorithm */
+	const uint8_t *hash;			/* Hash value */
+	int hash_size;				/* Hash size */
+};
+
+/**
+ * Read a flash entry from the fdt
+ *
+ * @param node	Reference to node to read
+ * @param name		Name of node being read
+ * @param entry		Place to put offset and size of this node
+ * @return 0 if ok, -ve on error
+ */
+int of_read_fmap_entry(ofnode node, const char *name,
+		       struct fmap_entry *entry);
+
+#endif