coverity: Fix MISRA null pointer violations

Fix code that violates the MISRA rule:
MISRA C-2012 Rule 11.9: Literal "0" shall not be used as
null pointer constant.

The fix explicitly checks whether a pointer is NULL.

Change-Id: Ibc318dc0f464982be9a34783f24ccd1d44800551
Signed-off-by: Zelalem <zelalem.aweke@arm.com>

bl1/aarch64/bl1_context_mgmt.c

 /*
- * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -69,7 +69,7 @@ void bl1_prepare_next_image(unsigned int image_id)
 	security_state = GET_SECURITY_STATE(next_bl_ep->h.attr);
 
 	/* Setup the Secure/Non-Secure context if not done already. */
-	if (!cm_get_context(security_state))
+	if (cm_get_context(security_state) == NULL)
 		cm_set_context(&bl1_cpu_context[security_state], security_state);
 
 	/* Prepare the SPSR for the next BL image. */

bl1/bl1_main.c

 /*
- * Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -26,7 +26,7 @@
 
 /* BL1 Service UUID */
 DEFINE_SVC_UUID2(bl1_svc_uid,
-	0xd46739fd, 0xcb72, 0x9a4d, 0xb5, 0x75,
+	U(0xd46739fd), 0xcb72, 0x9a4d, 0xb5, 0x75,
 	0x67, 0x15, 0xd6, 0xf4, 0xbb, 0x4a);
 
 static void bl1_load_bl2(void);
@@ -172,7 +172,7 @@ static void bl1_load_bl2(void)
 
 	/* Get the image descriptor */
 	image_desc = bl1_plat_get_image_desc(BL2_IMAGE_ID);
-	assert(image_desc);
+	assert(image_desc != NULL);
 
 	/* Get the image info */
 	image_info = &image_desc->image_info;
@@ -276,7 +276,7 @@ register_t bl1_smc_wrapper(uint32_t smc_fid,
 {
 	register_t x1, x2, x3, x4;
 
-	assert(handle);
+	assert(handle != NULL);
 
 	get_smc_params_from_ctx(handle, x1, x2, x3, x4);
 	return bl1_smc_handler(smc_fid, x1, x2, x3, x4, cookie, handle, flags);

bl2/bl2_image_load_v2.c

 /*
- * Copyright (c) 2016-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -35,13 +35,13 @@ struct entry_point_info *bl2_load_images(void)
 	 * Get information about the images to load.
 	 */
 	bl2_load_info = plat_get_bl_image_load_info();
-	assert(bl2_load_info);
-	assert(bl2_load_info->head);
+	assert(bl2_load_info != NULL);
+	assert(bl2_load_info->head != NULL);
 	assert(bl2_load_info->h.type == PARAM_BL_LOAD_INFO);
 	assert(bl2_load_info->h.version >= VERSION_2);
 	bl2_node_info = bl2_load_info->head;
 
-	while (bl2_node_info) {
+	while (bl2_node_info != NULL) {
 		/*
 		 * Perform platform setup before loading the image,
 		 * if indicated in the image attributes AND if NOT
@@ -91,11 +91,11 @@ struct entry_point_info *bl2_load_images(void)
 	 * Get information to pass to the next image.
 	 */
 	bl2_to_next_bl_params = plat_get_next_bl_params();
-	assert(bl2_to_next_bl_params);
-	assert(bl2_to_next_bl_params->head);
+	assert(bl2_to_next_bl_params != NULL);
+	assert(bl2_to_next_bl_params->head != NULL);
 	assert(bl2_to_next_bl_params->h.type == PARAM_BL_PARAMS);
 	assert(bl2_to_next_bl_params->h.version >= VERSION_2);
-	assert(bl2_to_next_bl_params->head->ep_info);
+	assert(bl2_to_next_bl_params->head->ep_info != NULL);
 
 	/* Populate arg0 for the next BL image if not already provided */
 	if (bl2_to_next_bl_params->head->ep_info->args.arg0 == (u_register_t)0)

common/desc_image_load.c

 /*
- * Copyright (c) 2016-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -301,9 +301,9 @@ void bl31_params_parse_helper(u_register_t param,
 			image_info_t *bl33_image_info;
 		} *v1 = (void *)(uintptr_t)param;
 		assert(v1->h.type == PARAM_BL31);
-		if (bl32_ep_info_out)
+		if (bl32_ep_info_out != NULL)
 			*bl32_ep_info_out = *v1->bl32_ep_info;
-		if (bl33_ep_info_out)
+		if (bl33_ep_info_out != NULL)
 			*bl33_ep_info_out = *v1->bl33_ep_info;
 		return;
 	}
@@ -311,12 +311,12 @@ void bl31_params_parse_helper(u_register_t param,
 
 	assert(v2->h.version == PARAM_VERSION_2);
 	assert(v2->h.type == PARAM_BL_PARAMS);
-	for (node = v2->head; node; node = node->next_params_info) {
+	for (node = v2->head; node != NULL; node = node->next_params_info) {
 		if (node->image_id == BL32_IMAGE_ID)
-			if (bl32_ep_info_out)
+			if (bl32_ep_info_out != NULL)
 				*bl32_ep_info_out = *node->ep_info;
 		if (node->image_id == BL33_IMAGE_ID)
-			if (bl33_ep_info_out)
+			if (bl33_ep_info_out != NULL)
 				*bl33_ep_info_out = *node->ep_info;
 	}
 }

drivers/console/multi_console.c

 /*
- * Copyright (c) 2018-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2018-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -90,7 +90,7 @@ int console_putc(int c)
 	console_t *console;
 
 	for (console = console_list; console != NULL; console = console->next)
-		if ((console->flags & console_state) && console->putc) {
+		if ((console->flags & console_state) && (console->putc != NULL)) {
 			int ret = do_putc(c, console);
 			if ((err == ERROR_NO_VALID_CONSOLE) || (ret < err))
 				err = ret;
@@ -107,7 +107,7 @@ int console_getc(void)
 	do {	/* Keep polling while at least one console works correctly. */
 		for (console = console_list; console != NULL;
 		     console = console->next)
-			if ((console->flags & console_state) && console->getc) {
+			if ((console->flags & console_state) && (console->getc != NULL)) {
 				int ret = console->getc(console);
 				if (ret >= 0)
 					return ret;
@@ -125,7 +125,7 @@ int console_flush(void)
 	console_t *console;
 
 	for (console = console_list; console != NULL; console = console->next)
-		if ((console->flags & console_state) && console->flush) {
+		if ((console->flags & console_state) && (console->flush != NULL)) {
 			int ret = console->flush(console);
 			if ((err == ERROR_NO_VALID_CONSOLE) || (ret < err))
 				err = ret;

lib/utils/mem_region.c

 /*
- * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2017-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -32,7 +32,7 @@ void clear_mem_regions(mem_region_t *tbl, size_t nregions)
 {
 	size_t i;
 
-	assert(tbl);
+	assert(tbl != NULL);
 	assert(nregions > 0);
 
 	for (i = 0; i < nregions; i++) {
@@ -114,7 +114,7 @@ int mem_region_in_array_chk(mem_region_t *tbl, size_t nregions,
 	uintptr_t region_start, region_end, start, end;
 	size_t i;
 
-	assert(tbl);
+	assert(tbl != NULL);
 	assert(nbytes > 0);
 	assert(!check_uptr_overflow(addr, nbytes-1));
 

plat/arm/common/arm_bl2_setup.c

 /*
- * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -150,7 +150,7 @@ int arm_bl2_handle_post_image_load(unsigned int image_id)
 	bl_mem_params_node_t *pager_mem_params = NULL;
 	bl_mem_params_node_t *paged_mem_params = NULL;
 #endif
-	assert(bl_mem_params);
+	assert(bl_mem_params != NULL);
 
 	switch (image_id) {
 #ifdef __aarch64__