[U-Boot] [PATCH v2] env: don't generate callback list entries for SPL

Scott Wood
2012-12-20T21:51:05Z

SPL doesn't write to the environment. These list entries prevent the
functions from being garbage-collected, even though nothing will look at
the list. This caused several SPL builds (e.g. P2020RDB-PC_NAND) to
break due to size limitations and/or unresolved symbols.

A static inline function is used to provide a context in which we
can consume the callback, and thus avoid unused function warnings.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Acked-by: Joe Hershberger <joe.hershberger@gmail.com>
---
v2: Update commit message to reflect that some SPLs do use the
environment, in a read-only fashion. Also update commit message
to indicate that the size of the included functions wasn't the only
problem seen.
---
include/env_callback.h | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/include/env_callback.h b/include/env_callback.h
index 47fdc6f..c583120 100644
--- a/include/env_callback.h
+++ b/include/env_callback.h
@@ -68,8 +68,16 @@ void env_callback_init(ENTRY *var_entry);
* when associated through the ".callbacks" environment variable, the callback
* will be executed any time the variable is inserted, overwritten, or deleted.
*/
+#ifdef CONFIG_SPL_BUILD
+#define U_BOOT_ENV_CALLBACK(name, callback) \
+ static inline void _u_boot_env_noop_##name(void) \
+ { \
+ (void)callback; \
+ }
+#else
#define U_BOOT_ENV_CALLBACK(name, callback) \
ll_entry_declare(struct env_clbk_tbl, name, env_clbk, env_clbk) = \
{#name, callback}
+#endif

#endif /* __ENV_CALLBACK_H__ */
--
1.7.9.5