of: Add cpu node iterator for_each_of_cpu_node()
Iterating thru cpu nodes is a common pattern. Create a common iterator
which can find child nodes either by node name or device_type == cpu.
Using the former will allow for eventually dropping device_type
properties which are deprecated for FDT.
Cc: Frank Rowand <frowand.list@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rob Herring <robh@kernel.org>
diff --git a/drivers/of/base.c b/drivers/of/base.c
index a055cd1..4807db0 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -742,6 +742,45 @@ struct device_node *of_get_next_available_child(const struct device_node *node,
EXPORT_SYMBOL(of_get_next_available_child);
/**
+ * of_get_next_cpu_node - Iterate on cpu nodes
+ * @prev: previous child of the /cpus node, or NULL to get first
+ *
+ * Returns a cpu node pointer with refcount incremented, use of_node_put()
+ * on it when done. Returns NULL when prev is the last child. Decrements
+ * the refcount of prev.
+ */
+struct device_node *of_get_next_cpu_node(struct device_node *prev)
+{
+ struct device_node *next = NULL;
+ unsigned long flags;
+ struct device_node *node;
+
+ if (!prev)
+ node = of_find_node_by_path("/cpus");
+
+ raw_spin_lock_irqsave(&devtree_lock, flags);
+ if (prev)
+ next = prev->sibling;
+ else if (node) {
+ next = node->child;
+ of_node_put(node);
+ }
+ for (; next; next = next->sibling) {
+ if (!(of_node_name_eq(next, "cpu") ||
+ (next->type && !of_node_cmp(next->type, "cpu"))))
+ continue;
+ if (!__of_device_is_available(next))
+ continue;
+ if (of_node_get(next))
+ break;
+ }
+ of_node_put(prev);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
+ return next;
+}
+EXPORT_SYMBOL(of_get_next_cpu_node);
+
+/**
* of_get_compatible_child - Find compatible child node
* @parent: parent node
* @compatible: compatible string
