@@ -73,6 +73,16 @@ static void add_deps(struct node *dt, struct node *node, struct property *prop)
is_parent_of(target, source))
continue;
phandle = get_node_phandle(dt, target);
+ prop_deps = get_property(node, "no-dependencies");
+ if (prop_deps) {
+ /* avoid adding non-dependencies */
+ cell = (cell_t *)prop_deps->val.val;
+ for (i = 0; i < prop_deps->val.len/4; ++i)
+ if (*cell++ == cpu_to_fdt32(phandle))
+ break;
+ if (i < prop_deps->val.len/4)
+ continue;
+ }
prop_deps = get_property(source, "dependencies");
if (!prop_deps) {
add_property(source,
@@ -102,9 +112,21 @@ static void process_nodes_props(struct node *dt, struct node *node)
process_nodes_props(dt, child);
}
+static void del_prop_no_dependencies(struct node *node)
+{
+ struct node *child;
+
+ if (!node)
+ return;
+ delete_property_by_name(node, "no-dependencies");
+ for_each_child(node, child)
+ del_prop_no_dependencies(child);
+}
+
void add_dependencies(struct boot_info *bi)
{
process_nodes_props(bi->dt, bi->dt);
+ del_prop_no_dependencies(bi->dt);
}
/*
In some rare cases it might make sense for not wanting an automatic dependency for some used phandles. E.g. if a cpu depends on a regulator which depends on i2c which depends on some bus and you want that the bus depends on the cpu. That would end up in a cycle. Usually such doesn't make sense because the hw doesn't support such circular dependencies too (you always have to start somewhere with initializing things). But e.g. in the case of the regulator the cpu depends on, it's very likely that the regulator was initialized automatically (otherwise the cpu won't run), so there is no real need to initialize the regulator before the cpu. But that's just an example for one of such rare cases where it might make sense to avoid an otherwise automatically added dependency. The syntax is like bar: whatever { ... }; foo { my-option = <&bar 1 2 3>; no-dependencies = <&bar>; }; Without that 'no-dependencies' property dtc would automatically add a dependency to bar to the property 'dependencies' of the node foo. But with that 'no-dependencies' it will not automatically add the listed dependencies. The property 'no-dependencies' is virtual property and will not be added to any output file. Signed-off-by: Alexander Holler <holler@ahsoftware.de> --- scripts/dtc/dependencies.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)