romstage_handoff: provide common logic for setup
The romstage_handoff structure can be utilized from different components
of the romstage -- some in the chipset code, some in coreboot's core
libarary. To ensure that all users handle initialization of a newly
added romstage_handoff structure properly, provide a common function to
handle structure initialization.
Change-Id: I3998c6bb228255f4fd93d27812cf749560b06e61
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/2795
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
diff --git a/src/include/romstage_handoff.h b/src/include/romstage_handoff.h
index 0cadfb5..13dc979 100644
--- a/src/include/romstage_handoff.h
+++ b/src/include/romstage_handoff.h
@@ -20,6 +20,8 @@
#define ROMSTAGE_HANDOFF_H
#include <stdint.h>
+#include <string.h>
+#include <cbmem.h>
/* It is the chipset's responsbility for maintaining the integrity of this
* structure in CBMEM. For instance, if chipset code adds this structure
@@ -31,5 +33,30 @@
uint32_t reserve_size;
};
+#if defined(__PRE_RAM__)
+/* The romstage_handoff_find_or_add() function provides the necessary logic
+ * for initializng the romstage_handoff structure in cbmem. Different components
+ * of the romstage may be responsible for setting up different fields. Therefore
+ * that same logic flow should be used for allocating and initializing the
+ * structure. A newly allocated structure will be memset to 0. */
+static inline struct romstage_handoff *romstage_handoff_find_or_add(void)
+{
+ struct romstage_handoff *handoff;
+
+ /* cbmem_add() first does a find and uses the old location before the
+ * real add. However, it is important to know when the structure is not
+ * found so it can be initialized to 0. */
+ handoff = cbmem_find(CBMEM_ID_ROMSTAGE_INFO);
+
+ if (handoff == NULL) {
+ handoff = cbmem_add(CBMEM_ID_ROMSTAGE_INFO, sizeof(*handoff));
+ if (handoff != NULL)
+ memset(handoff, 0, sizeof(*handoff));
+ }
+
+ return handoff;
+}
+#endif
+
#endif /* ROMSTAGE_HANDOFF_H */