Merge pull request #834 from douglas-raillard-arm/dr/use_dc_zva_zeroing

Use DC ZVA instruction to zero memory

1 files changed, 31 insertions, 0 deletions

diff --git a/include/lib/utils.h b/include/lib/utils.h
index b6bc9af6..69bbb430 100644
--- a/include/lib/utils.h
+++ b/include/lib/utils.h
@@ -80,4 +80,35 @@
 # define ULL(_x)	(_x##ull)
 #endif
 
+/*
+ * C code should be put in this part of the header to avoid breaking ASM files
+ * or linker scripts including it.
+ */
+#if !(defined(__LINKER__) || defined(__ASSEMBLY__))
+
+#include <types.h>
+
+/*
+ * Fill a region of normal memory of size "length" in bytes with zero bytes.
+ *
+ * WARNING: This function can only operate on normal memory. This means that
+ *          the MMU must be enabled when using this function. Otherwise, use
+ *          zeromem.
+ */
+void zero_normalmem(void *mem, u_register_t length);
+
+/*
+ * Fill a region of memory of size "length" in bytes with null bytes.
+ *
+ * Unlike zero_normalmem, this function has no restriction on the type of
+ * memory targeted and can be used for any device memory as well as normal
+ * memory. This function must be used instead of zero_normalmem when MMU is
+ * disabled.
+ *
+ * NOTE: When data cache and MMU are enabled, prefer zero_normalmem for faster
+ *       zeroing.
+ */
+void zeromem(void *mem, u_register_t length);
+#endif /* !(defined(__LINKER__) || defined(__ASSEMBLY__)) */
+
 #endif /* __UTILS_H__ */