[xen master] xen/device-tree: Add dt_find_node_by_path_from() to find nodes in device tree

[patchbot@xxxxxxx]

commit 25141fed24e0e1a23fa3fef6195d640318c21e64
Author:     Vikram Garhwal <vikram.garhwal@xxxxxxx>
AuthorDate: Tue Sep 5 18:16:18 2023 -0700
Commit:     Stefano Stabellini <stefano.stabellini@xxxxxxx>
CommitDate: Tue Sep 5 18:25:44 2023 -0700

    xen/device-tree: Add dt_find_node_by_path_from() to find nodes in device 
tree
    
    Add dt_find_node_by_path_from() to find a matching node with path for a
    dt_device_node.
    
    Reason behind this function:
        Each time overlay nodes are added using .dtbo, a new fdt (memcpy of
        device_tree_flattened) is created and updated with overlay nodes. This
        updated fdt is further unflattened to a dt_host_new. Next, we need to 
find
        the overlay nodes in dt_host_new, find the overlay node's parent in 
dt_host
        and add the nodes as child under their parent in the dt_host. Thus we 
need
        this function to search for node in different unflattened device trees.
    
    Also, make dt_find_node_by_path() static inline.
    
    Signed-off-by: Vikram Garhwal <vikram.garhwal@xxxxxxx>
    Reviewed-by: Michal Orzel <michal.orzel@xxxxxxx>
    Acked-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
---
 xen/common/device_tree.c      |  5 +++--
 xen/include/xen/device_tree.h | 17 +++++++++++++++--
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/xen/common/device_tree.c b/xen/common/device_tree.c
index b8ef1c7ae2..f38f51ec0b 100644
--- a/xen/common/device_tree.c
+++ b/xen/common/device_tree.c
@@ -358,11 +358,12 @@ struct dt_device_node *dt_find_node_by_type(struct 
dt_device_node *from,
     return np;
 }
 
-struct dt_device_node *dt_find_node_by_path(const char *path)
+struct dt_device_node *dt_find_node_by_path_from(struct dt_device_node *from,
+                                                 const char *path)
 {
     struct dt_device_node *np;
 
-    dt_for_each_device_node(dt_host, np)
+    dt_for_each_device_node(from, np)
         if ( np->full_name && (dt_node_cmp(np->full_name, path) == 0) )
             break;
 
diff --git a/xen/include/xen/device_tree.h b/xen/include/xen/device_tree.h
index a518310a62..44d315c8ba 100644
--- a/xen/include/xen/device_tree.h
+++ b/xen/include/xen/device_tree.h
@@ -570,13 +570,26 @@ struct dt_device_node *dt_find_node_by_type(struct 
dt_device_node *from,
 struct dt_device_node *dt_find_node_by_alias(const char *alias);
 
 /**
- * dt_find_node_by_path - Find a node matching a full DT path
+ * dt_find_node_by_path_from - Generic function to find a node matching the
+ * full DT path for any given unflatten device tree
+ * @from: The device tree node to start searching from
  * @path: The full path to match
  *
  * Returns a node pointer.
  */
-struct dt_device_node *dt_find_node_by_path(const char *path);
+struct dt_device_node *dt_find_node_by_path_from(struct dt_device_node *from,
+                                                 const char *path);
 
+/**
+ * dt_find_node_by_path - Find a node matching a full DT path in dt_host
+ * @path: The full path to match
+ *
+ * Returns a node pointer.
+ */
+static inline struct dt_device_node *dt_find_node_by_path(const char *path)
+{
+    return dt_find_node_by_path_from(dt_host, path);
+}
 
 /**
  * dt_find_node_by_gpath - Same as dt_find_node_by_path but retrieve the
--
generated by git-patchbot for /home/xen/git/xen.git#master