overlay: Add syntactic sugar version of overlays

For simple overlays that use a single target there exists a
simpler syntax version.

&foo { }; generates an overlay with a single target at foo.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 22 insertions, 0 deletions

diff --git a/livetree.c b/livetree.c
index c815176..6846ad2 100644
--- a/livetree.c
+++ b/livetree.c
@@ -216,6 +216,28 @@ struct node *merge_nodes(struct node *old_node, struct node *new_node)
 	return old_node;
 }
 
+void add_orphan_node(struct node *dt, struct node *new_node, char *ref)
+{
+	static unsigned int next_orphan_fragment = 0;
+	struct node *node;
+	struct property *p;
+	struct data d = empty_data;
+	char *name;
+
+	d = data_add_marker(d, REF_PHANDLE, ref);
+	d = data_append_integer(d, 0xffffffff, 32);
+
+	p = build_property("target", d);
+
+	xasprintf(&name, "fragment@%u",
+			next_orphan_fragment++);
+	name_node(new_node, "__overlay__");
+	node = build_node(p, new_node);
+	name_node(node, name);
+
+	add_child(dt, node);
+}
+
 struct node *chain_node(struct node *first, struct node *list)
 {
 	assert(first->next_sibling == NULL);