When enabling CONFIG_OF on a platform where of_root is not populated by
firmware, we end up without a root node. In order to apply overlays and
create subnodes of the root node, we need one. This commit creates an
empty root node if not present.
Co-developed-by: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Clément Léger <clement.leger@xxxxxxxxxxx>
---
drivers/of/base.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index e7d92b67cb8a..6b8584c39f73 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -177,6 +177,19 @@ void __init of_core_init(void)
pr_err("failed to register existing nodes\n");
return;
}
+
+ if (!of_root) {
+ of_root = kzalloc(sizeof(*of_root), GFP_KERNEL);
+ if (!of_root) {
+ mutex_unlock(&of_mutex);
+ pr_err("failed to create root node\n");
+ return;
+ }
+
+ of_root->full_name = "/";
+ of_node_init(of_root);
+ }
+
for_each_of_allnodes(np) {
__of_attach_node_sysfs(np);
if (np->phandle && !phandle_cache[of_phandle_cache_hash(np->phandle)])
@@ -185,8 +198,7 @@ void __init of_core_init(void)
mutex_unlock(&of_mutex);
/* Symlink in /proc as required by userspace ABI */
- if (of_root)
- proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base");
+ proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base");
}
static struct property *__of_find_property(const struct device_node *np,
--
2.34.1
