From 96a56244a5df7eff60252890f7c4bb6ce8fee19a Mon Sep 17 00:00:00 2001
From: Damjan Marion <damarion@cisco.com>
Date: Tue, 8 Oct 2024 20:47:38 +0200
Subject: [PATCH] vppinfra: devicetree improvements

Type: improvement
Change-Id: If20ae74658702399f626b1af7bd3519e05a5d422
Signed-off-by: Damjan Marion <damarion@cisco.com>
---
 .clang-format             |  2 ++
 src/vppinfra/devicetree.c | 17 +++++++++----
 src/vppinfra/devicetree.h | 50 +++++++++++++++++++++++++++++++++++++--
 3 files changed, 63 insertions(+), 6 deletions(-)

diff --git a/.clang-format b/.clang-format
index 798a8c39a35..e4855fce047 100644
--- a/.clang-format
+++ b/.clang-format
@@ -35,6 +35,8 @@ ForEachMacros:
   - 'foreach_vnet_dev_port'
   - 'foreach_vnet_dev_args'
   - 'foreach_vnet_dev_port_args'
+  - 'foreach_clib_dt_tree_node'
+  - 'foreach_clib_dt_child_node'
 
 StatementMacros:
   - 'CLIB_MULTIARCH_FN'
diff --git a/src/vppinfra/devicetree.c b/src/vppinfra/devicetree.c
index b725d5a0aed..df5a24f198e 100644
--- a/src/vppinfra/devicetree.c
+++ b/src/vppinfra/devicetree.c
@@ -192,9 +192,16 @@ done:
 }
 #endif
 
-clib_dt_node_t *
-clib_dt_get_child_node (clib_dt_node_t *n, char *name)
+__clib_export clib_dt_node_t *
+clib_dt_get_child_node (clib_dt_node_t *n, char *fmt, ...)
 {
+  u8 *s;
+  va_list va;
+  va_start (va, fmt);
+  s = va_format (0, fmt, &va);
+  va_end (va);
+  vec_add1 (s, 0);
+
   vec_foreach_pointer (cn, n->child_nodes)
     {
       u8 *p = cn->path + vec_len (cn->path) - 1;
@@ -206,15 +213,17 @@ clib_dt_get_child_node (clib_dt_node_t *n, char *name)
       if (p[-1] != '/')
 	continue;
 
-      while (p[i] == name[i] && name[i] != 0)
+      while (p[i] == s[i] && s[i] != 0)
 	i++;
 
-      if (name[i] != 0)
+      if (s[i] != 0)
 	continue;
 
+      vec_free (s);
       return cn;
     }
 
+  vec_free (s);
   return 0;
 }
 
diff --git a/src/vppinfra/devicetree.h b/src/vppinfra/devicetree.h
index 21c2e0f7006..db7d8411a11 100644
--- a/src/vppinfra/devicetree.h
+++ b/src/vppinfra/devicetree.h
@@ -42,6 +42,8 @@ typedef struct clib_dt_main
   uword *node_by_phandle;
 } clib_dt_main_t;
 
+__clib_export clib_dt_node_t *clib_dt_get_child_node (clib_dt_node_t *n,
+						      char *fmt, ...);
 clib_dt_node_t *clib_dt_get_node_with_path (clib_dt_main_t *dm, char *fmt,
 					    ...);
 clib_dt_property_t *clib_dt_get_node_property_by_name (clib_dt_node_t *,
@@ -56,7 +58,7 @@ format_function_t format_clib_dt_desc;
 format_function_t format_clib_dt_property_data;
 
 static_always_inline int
-clib_dt_proprerty_is_u32 (clib_dt_property_t *p)
+clib_dt_property_is_u32 (clib_dt_property_t *p)
 {
   if (p == 0 || p->size != 4)
     return 0;
@@ -64,9 +66,53 @@ clib_dt_proprerty_is_u32 (clib_dt_property_t *p)
 }
 
 static_always_inline u32
-clib_dt_proprerty_get_u32 (clib_dt_property_t *p)
+clib_dt_property_get_u32 (clib_dt_property_t *p)
 {
   return clib_net_to_host_u32 (*(u32u *) p->data);
 }
 
+static_always_inline char *
+clib_dt_property_get_string (clib_dt_property_t *p)
+{
+  return (char *) p->data;
+}
+
+static_always_inline clib_dt_node_t *
+clib_dt_get_root_node (clib_dt_node_t *n)
+{
+  return n->dt_main->root;
+}
+
+static_always_inline clib_dt_node_t *
+foreach_clib_dt_tree_node_helper (clib_dt_node_t *first, clib_dt_node_t **prev,
+				  clib_dt_node_t *n)
+{
+  clib_dt_node_t *next;
+
+again:
+  if ((!*prev || (*prev)->parent != n) && vec_len (n->child_nodes) > 0)
+    next = n->child_nodes[0];
+  else if (n->next)
+    next = n->next;
+  else
+    {
+      next = n->parent;
+      *prev = n;
+      n = next;
+      if (n == first)
+	return 0;
+      goto again;
+    }
+
+  *prev = n;
+  return next == first ? 0 : next;
+}
+
+#define foreach_clib_dt_child_node(_cn, _n)                                   \
+  vec_foreach_pointer (_cn, (_n)->child_nodes)
+
+#define foreach_clib_dt_tree_node(_n, _first)                                 \
+  for (clib_dt_node_t *__last = 0, *(_n) = _first; _n;                        \
+       _n = foreach_clib_dt_tree_node_helper (_first, &__last, _n))
+
 #endif /* CLIB_DEVICETREE_H_ */