dm: core: Introduce support for multiple trees
At present ofnode only works with a single device tree, for the most part.
This is the control FDT used by U-Boot.
When booting an OS we may obtain a different device tree and want to
modify it. Add some initial support for this into the ofnode API.
Note that we don't permit aliases in this other device tree, since the
of_access implementation maintains a list of aliases collected at
start-up. Also, we don't need aliases to do fixups in the other FDT. So
make sure that flat tree and live tree processing are consistent in this
area.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/dm/of_access.h b/include/dm/of_access.h
index ec6e6e2..078f2ea 100644
--- a/include/dm/of_access.h
+++ b/include/dm/of_access.h
@@ -197,6 +197,11 @@
/**
* of_find_node_opts_by_path() - Find a node matching a full OF path
*
+ * Note that alias processing is only available on the control FDT (gd->of_root).
+ * For other trees it is skipped, so any attempt to obtain an alias will result
+ * in returning NULL.
+ *
+ * @root: Root node of the tree to use. If this is NULL, then gd->of_root is used
* @path: Either the full path to match, or if the path does not start with
* '/', the name of a property of the /aliases node (an alias). In the
* case of an alias, the node matching the alias' value will be returned.
@@ -210,12 +215,13 @@
*
* Return: a node pointer or NULL if not found
*/
-struct device_node *of_find_node_opts_by_path(const char *path,
+struct device_node *of_find_node_opts_by_path(struct device_node *root,
+ const char *path,
const char **opts);
static inline struct device_node *of_find_node_by_path(const char *path)
{
- return of_find_node_opts_by_path(path, NULL);
+ return of_find_node_opts_by_path(NULL, path, NULL);
}
/**