[PATCH v3 03/42] linker_lists: Allow use in data structures

[Simon Glass]

At present linker lists are designed for use in code. They make use of
statements within expressions ({...}), for example.

It is possible to generate a reference to a linker_list entry that can
be used in data structures, where such features are not permitted. It
requires that the reference first be declared as extern. In other
words the existing macro needs to be split into two parts.

Add new macros to support this.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

Changes in v3:
- Drop the decl() variant since it is just as easy to use extern

 include/linker_lists.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/linker_lists.h b/include/linker_lists.h
index fd98ecd297c..0ca30da4172 100644
--- a/include/linker_lists.h
+++ b/include/linker_lists.h
@@ -211,6 +211,18 @@
 		_ll_result;						\
 	})
 
+/**
+ * ll_entry_ref() - Get a reference to a linker-generated array entry
+ *
+ * Once ll_entry_decl() has been used to declare the reference, this macro
+ * allows the entry to be accessed.
+ *
+ * This is like ll_entry_get(), but without the extra code, so it is suitable
+ * for putting into data structures.
+ */
+#define ll_entry_ref(_type, _name, _list)				\
+	((_type *)&_u_boot_list_2_##_list##_2_##_name)
+
 /**
  * ll_start() - Point to first entry of first linker-generated array
  * @_type:	Data type of the entry
-- 
2.30.0.478.g8a0d178c01-goog