dt: Add helper function for last_phandle updates

Add helper functions for "last_phandle" access/update and
modify functions to use helper functions.

Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>

core/device.c

@@ -57,7 +57,7 @@ static struct dt_node *new_node(const char *name)
 	list_head_init(&node->properties);
 	list_head_init(&node->children);
 	/* FIXME: locking? */
-	node->phandle = ++last_phandle;
+	node->phandle = new_phandle();
 	return node;
 }
 
@@ -469,7 +469,7 @@ struct dt_property *dt_add_property(struct dt_node *node,
 		assert(size == 4);
 		node->phandle = *(const u32 *)val;
 		if (node->phandle >= last_phandle)
-			last_phandle = node->phandle;
+			set_last_phandle(node->phandle);
 		return NULL;
 	}
 

core/fdt.c

@@ -191,11 +191,11 @@ void *create_dtb(const struct dt_node *root, bool exclusive)
 {
 	void *fdt = NULL;
 	size_t len = DEVICE_TREE_MAX_SIZE;
-	uint32_t old_last_phandle = last_phandle;
+	uint32_t old_last_phandle = get_last_phandle();
 	int ret;
 
 	do {
-		last_phandle = old_last_phandle;
+		set_last_phandle(old_last_phandle);
 		fdt_error = 0;
 		fdt = malloc(len);
 		if (!fdt) {
@@ -244,10 +244,10 @@ static int64_t opal_get_device_tree(uint32_t phandle,
 		return OPAL_PARAMETER;
 
 	fdt_error = 0;
-	old_last_phandle = last_phandle;
+	old_last_phandle = get_last_phandle();
 	ret = __create_dtb(fdt, len, root, true);
 	if (ret) {
-		last_phandle = old_last_phandle;
+		set_last_phandle(old_last_phandle);
 		if (ret == -FDT_ERR_NOSPACE)
 			return OPAL_NO_MEM;
 

include/device.h

@@ -61,6 +61,22 @@ struct dt_node *dt_new_root(const char *name);
 /* Graft a root node into this tree. */
 bool dt_attach_root(struct dt_node *parent, struct dt_node *root);
 
+/* Wrappers for last_phandle operations */
+static inline u32 get_last_phandle(void)
+{
+	return last_phandle;
+}
+
+static inline void set_last_phandle(u32 phandle)
+{
+	last_phandle = phandle;
+}
+
+static inline u32 new_phandle(void)
+{
+	return ++last_phandle;
+}
+
 /* Add a child node. */
 struct dt_node *dt_new(struct dt_node *parent, const char *name);
 struct dt_node *dt_new_addr(struct dt_node *parent, const char *name,