Replace some memset call by zeromem

Replace all use of memset by zeromem when zeroing moderately-sized
structure by applying the following transformation:
memset(x, 0, sizeof(x)) => zeromem(x, sizeof(x))

As the Trusted Firmware is compiled with -ffreestanding, it forbids the
compiler from using __builtin_memset and forces it to generate calls to
the slow memset implementation. Zeromem is a near drop in replacement
for this use case, with a more efficient implementation on both AArch32
and AArch64.

Change-Id: Ia7f3a90e888b96d056881be09f0b4d65b41aa79e
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
diff --git a/plat/arm/common/arm_bl2_setup.c b/plat/arm/common/arm_bl2_setup.c
index 5f30708..007108d 100644
--- a/plat/arm/common/arm_bl2_setup.c
+++ b/plat/arm/common/arm_bl2_setup.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -38,6 +38,7 @@
 #include <plat_arm.h>
 #include <platform_def.h>
 #include <string.h>
+#include <utils.h>
 
 /* Data structure which holds the extents of the trusted SRAM for BL2 */
 static meminfo_t bl2_tzram_layout __aligned(CACHE_WRITEBACK_GRANULE);
@@ -123,7 +124,7 @@
 	 * Initialise the memory for all the arguments that needs to
 	 * be passed to BL31
 	 */
-	memset(&bl31_params_mem, 0, sizeof(bl2_to_bl31_params_mem_t));
+	zeromem(&bl31_params_mem, sizeof(bl2_to_bl31_params_mem_t));
 
 	/* Assign memory for TF related information */
 	bl2_to_bl31_params = &bl31_params_mem.bl31_params;
diff --git a/plat/arm/css/drivers/scpi/css_scpi.c b/plat/arm/css/drivers/scpi/css_scpi.c
index f419abd..65ae978 100644
--- a/plat/arm/css/drivers/scpi/css_scpi.c
+++ b/plat/arm/css/drivers/scpi/css_scpi.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2014-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -34,6 +34,7 @@
 #include <debug.h>
 #include <platform.h>
 #include <string.h>
+#include <utils.h>
 #include "css_mhu.h"
 #include "css_scpi.h"
 
@@ -204,7 +205,8 @@
 	scpi_secure_message_start();
 
 	/* Populate request headers */
-	cmd = memset(SCPI_CMD_HEADER_AP_TO_SCP, 0, sizeof(*cmd));
+	zeromem(SCPI_CMD_HEADER_AP_TO_SCP, sizeof(*cmd));
+	cmd = SCPI_CMD_HEADER_AP_TO_SCP;
 	cmd->id = SCPI_CMD_GET_CSS_POWER_STATE;
 
 	/*