diff --git a/lib/psci/psci_off.c b/lib/psci/psci_off.c
index 231deea..944f8bf 100644
--- a/lib/psci/psci_off.c
+++ b/lib/psci/psci_off.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -40,14 +40,15 @@
  ******************************************************************************/
 int psci_do_cpu_off(unsigned int end_pwrlvl)
 {
-	int rc = PSCI_E_SUCCESS, idx = plat_my_core_pos();
+	int rc = PSCI_E_SUCCESS;
+	int idx = (int) plat_my_core_pos();
 	psci_power_state_t state_info;
 
 	/*
 	 * This function must only be called on platforms where the
 	 * CPU_OFF platform hooks have been implemented.
 	 */
-	assert(psci_plat_pm_ops->pwr_domain_off);
+	assert(psci_plat_pm_ops->pwr_domain_off != NULL);
 
 	/* Construct the psci_power_state for CPU_OFF */
 	psci_set_power_off_state(&state_info);
@@ -57,17 +58,16 @@
 	 * level so that by the time all locks are taken, the system topology
 	 * is snapshot and state management can be done safely.
 	 */
-	psci_acquire_pwr_domain_locks(end_pwrlvl,
-				      idx);
+	psci_acquire_pwr_domain_locks(end_pwrlvl, idx);
 
 	/*
 	 * Call the cpu off handler registered by the Secure Payload Dispatcher
 	 * to let it do any bookkeeping. Assume that the SPD always reports an
 	 * E_DENIED error if SP refuse to power down
 	 */
-	if (psci_spd_pm && psci_spd_pm->svc_off) {
+	if ((psci_spd_pm != NULL) && (psci_spd_pm->svc_off != NULL)) {
 		rc = psci_spd_pm->svc_off(0);
-		if (rc)
+		if (rc != 0)
 			goto exit;
 	}
 
@@ -120,8 +120,7 @@
 	 * Release the locks corresponding to each power level in the
 	 * reverse order to which they were acquired.
 	 */
-	psci_release_pwr_domain_locks(end_pwrlvl,
-				      idx);
+	psci_release_pwr_domain_locks(end_pwrlvl, idx);
 
 	/*
 	 * Check if all actions needed to safely power down this cpu have
@@ -154,7 +153,7 @@
 		    PMF_NO_CACHE_MAINT);
 #endif
 
-		if (psci_plat_pm_ops->pwr_domain_pwr_down_wfi) {
+		if (psci_plat_pm_ops->pwr_domain_pwr_down_wfi != NULL) {
 			/* This function must not return */
 			psci_plat_pm_ops->pwr_domain_pwr_down_wfi(&state_info);
 		} else {
diff --git a/lib/psci/psci_on.c b/lib/psci/psci_on.c
index 325346e..f38900c 100644
--- a/lib/psci/psci_on.c
+++ b/lib/psci/psci_on.c
@@ -55,22 +55,22 @@
  * platform handler as it can return error.
  ******************************************************************************/
 int psci_cpu_on_start(u_register_t target_cpu,
-		      entry_point_info_t *ep)
+		      const entry_point_info_t *ep)
 {
 	int rc;
-	unsigned int target_idx = plat_core_pos_by_mpidr(target_cpu);
 	aff_info_state_t target_aff_state;
+	int target_idx = plat_core_pos_by_mpidr(target_cpu);
 
 	/* Calling function must supply valid input arguments */
-	assert((int) target_idx >= 0);
+	assert(target_idx >= 0);
 	assert(ep != NULL);
 
 	/*
 	 * This function must only be called on platforms where the
 	 * CPU_ON platform hooks have been implemented.
 	 */
-	assert(psci_plat_pm_ops->pwr_domain_on &&
-			psci_plat_pm_ops->pwr_domain_on_finish);
+	assert((psci_plat_pm_ops->pwr_domain_on != NULL) &&
+	       (psci_plat_pm_ops->pwr_domain_on_finish != NULL));
 
 	/* Protect against multiple CPUs trying to turn ON the same target CPU */
 	psci_spin_lock_cpu(target_idx);
@@ -91,7 +91,8 @@
 	 * target CPUs shutdown was not seen by the current CPU's cluster. And
 	 * so the cache may contain stale data for the target CPU.
 	 */
-	flush_cpu_data_by_index(target_idx, psci_svc_cpu_data.aff_info_state);
+	flush_cpu_data_by_index((unsigned int)target_idx,
+				psci_svc_cpu_data.aff_info_state);
 	rc = cpu_on_validate_state(psci_get_aff_info_state_by_idx(target_idx));
 	if (rc != PSCI_E_SUCCESS)
 		goto exit;
@@ -101,7 +102,7 @@
 	 * to let it do any bookeeping. If the handler encounters an error, it's
 	 * expected to assert within
 	 */
-	if (psci_spd_pm && psci_spd_pm->svc_on)
+	if ((psci_spd_pm != NULL) && (psci_spd_pm->svc_on != NULL))
 		psci_spd_pm->svc_on(target_cpu);
 
 	/*
@@ -110,7 +111,8 @@
 	 * turned OFF.
 	 */
 	psci_set_aff_info_state_by_idx(target_idx, AFF_STATE_ON_PENDING);
-	flush_cpu_data_by_index(target_idx, psci_svc_cpu_data.aff_info_state);
+	flush_cpu_data_by_index((unsigned int)target_idx,
+				psci_svc_cpu_data.aff_info_state);
 
 	/*
 	 * The cache line invalidation by the target CPU after setting the
@@ -122,9 +124,11 @@
 	if (target_aff_state != AFF_STATE_ON_PENDING) {
 		assert(target_aff_state == AFF_STATE_OFF);
 		psci_set_aff_info_state_by_idx(target_idx, AFF_STATE_ON_PENDING);
-		flush_cpu_data_by_index(target_idx, psci_svc_cpu_data.aff_info_state);
+		flush_cpu_data_by_index((unsigned int)target_idx,
+					psci_svc_cpu_data.aff_info_state);
 
-		assert(psci_get_aff_info_state_by_idx(target_idx) == AFF_STATE_ON_PENDING);
+		assert(psci_get_aff_info_state_by_idx(target_idx) ==
+		       AFF_STATE_ON_PENDING);
 	}
 
 	/*
@@ -136,15 +140,16 @@
 	 * steps to power on.
 	 */
 	rc = psci_plat_pm_ops->pwr_domain_on(target_cpu);
-	assert(rc == PSCI_E_SUCCESS || rc == PSCI_E_INTERN_FAIL);
+	assert((rc == PSCI_E_SUCCESS) || (rc == PSCI_E_INTERN_FAIL));
 
 	if (rc == PSCI_E_SUCCESS)
 		/* Store the re-entry information for the non-secure world. */
-		cm_init_context_by_index(target_idx, ep);
+		cm_init_context_by_index((unsigned int)target_idx, ep);
 	else {
 		/* Restore the state on error. */
 		psci_set_aff_info_state_by_idx(target_idx, AFF_STATE_OFF);
-		flush_cpu_data_by_index(target_idx, psci_svc_cpu_data.aff_info_state);
+		flush_cpu_data_by_index((unsigned int)target_idx,
+					psci_svc_cpu_data.aff_info_state);
 	}
 
 exit:
@@ -157,8 +162,7 @@
  * are called by the common finisher routine in psci_common.c. The `state_info`
  * is the psci_power_state from which this CPU has woken up from.
  ******************************************************************************/
-void psci_cpu_on_finish(unsigned int cpu_idx,
-			psci_power_state_t *state_info)
+void psci_cpu_on_finish(int cpu_idx, const psci_power_state_t *state_info)
 {
 	/*
 	 * Plat. management: Perform the platform specific actions
@@ -199,7 +203,7 @@
 	 * Dispatcher to let it do any bookeeping. If the handler encounters an
 	 * error, it's expected to assert within
 	 */
-	if (psci_spd_pm && psci_spd_pm->svc_on_finish)
+	if ((psci_spd_pm != NULL) && (psci_spd_pm->svc_on_finish != NULL))
 		psci_spd_pm->svc_on_finish(0);
 
 	PUBLISH_EVENT(psci_cpu_on_finish);
diff --git a/lib/psci/psci_private.h b/lib/psci/psci_private.h
index 7eb2fc0..ac99876 100644
--- a/lib/psci/psci_private.h
+++ b/lib/psci/psci_private.h
@@ -295,22 +295,20 @@
 
 /* Private exported functions from psci_on.c */
 int psci_cpu_on_start(u_register_t target_cpu,
-		      entry_point_info_t *ep);
+		      const entry_point_info_t *ep);
 
-void psci_cpu_on_finish(unsigned int cpu_idx,
-			psci_power_state_t *state_info);
+void psci_cpu_on_finish(int cpu_idx, const psci_power_state_t *state_info);
 
 /* Private exported functions from psci_off.c */
 int psci_do_cpu_off(unsigned int end_pwrlvl);
 
 /* Private exported functions from psci_suspend.c */
-void psci_cpu_suspend_start(entry_point_info_t *ep,
+void psci_cpu_suspend_start(const entry_point_info_t *ep,
 			unsigned int end_pwrlvl,
 			psci_power_state_t *state_info,
 			unsigned int is_power_down_state);
 
-void psci_cpu_suspend_finish(unsigned int cpu_idx,
-			psci_power_state_t *state_info);
+void psci_cpu_suspend_finish(int cpu_idx, const psci_power_state_t *state_info);
 
 /* Private exported functions from psci_helpers.S */
 void psci_do_pwrdown_cache_maintenance(unsigned int pwr_level);
@@ -319,7 +317,7 @@
 /* Private exported functions from psci_system_off.c */
 void __dead2 psci_system_off(void);
 void __dead2 psci_system_reset(void);
-int psci_system_reset2(uint32_t reset_type, u_register_t cookie);
+u_register_t psci_system_reset2(uint32_t reset_type, u_register_t cookie);
 
 /* Private exported functions from psci_stat.c */
 void psci_stats_update_pwr_down(unsigned int end_pwrlvl,
diff --git a/lib/psci/psci_suspend.c b/lib/psci/psci_suspend.c
index a77972d..e00819d 100644
--- a/lib/psci/psci_suspend.c
+++ b/lib/psci/psci_suspend.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -23,7 +23,7 @@
  * This function does generic and platform specific operations after a wake-up
  * from standby/retention states at multiple power levels.
  ******************************************************************************/
-static void psci_suspend_to_standby_finisher(unsigned int cpu_idx,
+static void psci_suspend_to_standby_finisher(int cpu_idx,
 					     unsigned int end_pwrlvl)
 {
 	psci_power_state_t state_info;
@@ -64,8 +64,8 @@
  * operations.
  ******************************************************************************/
 static void psci_suspend_to_pwrdown_start(unsigned int end_pwrlvl,
-					  entry_point_info_t *ep,
-					  psci_power_state_t *state_info)
+					  const entry_point_info_t *ep,
+					  const psci_power_state_t *state_info)
 {
 	unsigned int max_off_lvl = psci_find_max_off_lvl(state_info);
 
@@ -85,7 +85,7 @@
 	 * Dispatcher to let it do any book-keeping. If the handler encounters an
 	 * error, it's expected to assert within
 	 */
-	if (psci_spd_pm && psci_spd_pm->svc_suspend)
+	if ((psci_spd_pm != NULL) && (psci_spd_pm->svc_suspend != NULL))
 		psci_spd_pm->svc_suspend(max_off_lvl);
 
 #if !HW_ASSISTED_COHERENCY
@@ -95,7 +95,7 @@
 	 * HW_ASSISTED_COHERENCY = 0 platforms that can safely perform these
 	 * actions with data caches enabled.
 	 */
-	if (psci_plat_pm_ops->pwr_domain_suspend_pwrdown_early)
+	if (psci_plat_pm_ops->pwr_domain_suspend_pwrdown_early != NULL)
 		psci_plat_pm_ops->pwr_domain_suspend_pwrdown_early(state_info);
 #endif
 
@@ -147,20 +147,20 @@
  * the state transition has been done, no further error is expected and it is
  * not possible to undo any of the actions taken beyond that point.
  ******************************************************************************/
-void psci_cpu_suspend_start(entry_point_info_t *ep,
+void psci_cpu_suspend_start(const entry_point_info_t *ep,
 			    unsigned int end_pwrlvl,
 			    psci_power_state_t *state_info,
 			    unsigned int is_power_down_state)
 {
 	int skip_wfi = 0;
-	unsigned int idx = plat_my_core_pos();
+	int idx = (int) plat_my_core_pos();
 
 	/*
 	 * This function must only be called on platforms where the
 	 * CPU_SUSPEND platform hooks have been implemented.
 	 */
-	assert(psci_plat_pm_ops->pwr_domain_suspend &&
-			psci_plat_pm_ops->pwr_domain_suspend_finish);
+	assert((psci_plat_pm_ops->pwr_domain_suspend != NULL) &&
+	       (psci_plat_pm_ops->pwr_domain_suspend_finish != NULL));
 
 	/*
 	 * This function acquires the lock corresponding to each power
@@ -175,7 +175,7 @@
 	 * introduced by lock contention to increase the chances of early
 	 * detection that a wake-up interrupt has fired.
 	 */
-	if (read_isr_el1()) {
+	if (read_isr_el1() != 0U) {
 		skip_wfi = 1;
 		goto exit;
 	}
@@ -192,7 +192,7 @@
 	psci_stats_update_pwr_down(end_pwrlvl, state_info);
 #endif
 
-	if (is_power_down_state)
+	if (is_power_down_state != 0U)
 		psci_suspend_to_pwrdown_start(end_pwrlvl, ep, state_info);
 
 	/*
@@ -214,10 +214,10 @@
 	 */
 	psci_release_pwr_domain_locks(end_pwrlvl,
 				  idx);
-	if (skip_wfi)
+	if (skip_wfi == 1)
 		return;
 
-	if (is_power_down_state) {
+	if (is_power_down_state != 0U) {
 #if ENABLE_RUNTIME_INSTRUMENTATION
 
 		/*
@@ -232,7 +232,7 @@
 #endif
 
 		/* The function calls below must not return */
-		if (psci_plat_pm_ops->pwr_domain_pwr_down_wfi)
+		if (psci_plat_pm_ops->pwr_domain_pwr_down_wfi != NULL)
 			psci_plat_pm_ops->pwr_domain_pwr_down_wfi(state_info);
 		else
 			psci_power_down_wfi();
@@ -269,15 +269,15 @@
  * are called by the common finisher routine in psci_common.c. The `state_info`
  * is the psci_power_state from which this CPU has woken up from.
  ******************************************************************************/
-void psci_cpu_suspend_finish(unsigned int cpu_idx,
-			     psci_power_state_t *state_info)
+void psci_cpu_suspend_finish(int cpu_idx, const psci_power_state_t *state_info)
 {
 	unsigned int counter_freq;
 	unsigned int max_off_lvl;
 
 	/* Ensure we have been woken up from a suspended state */
-	assert(psci_get_aff_info_state() == AFF_STATE_ON && is_local_state_off(\
-			state_info->pwr_domain_state[PSCI_CPU_PWR_LVL]));
+	assert((psci_get_aff_info_state() == AFF_STATE_ON) &&
+		(is_local_state_off(
+			state_info->pwr_domain_state[PSCI_CPU_PWR_LVL]) != 0));
 
 	/*
 	 * Plat. management: Perform the platform specific actions
@@ -302,9 +302,9 @@
 	 * Dispatcher to let it do any bookeeping. If the handler encounters an
 	 * error, it's expected to assert within
 	 */
-	if (psci_spd_pm && psci_spd_pm->svc_suspend_finish) {
+	if ((psci_spd_pm != NULL) && (psci_spd_pm->svc_suspend_finish != NULL)) {
 		max_off_lvl = psci_find_max_off_lvl(state_info);
-		assert (max_off_lvl != PSCI_INVALID_PWR_LVL);
+		assert(max_off_lvl != PSCI_INVALID_PWR_LVL);
 		psci_spd_pm->svc_suspend_finish(max_off_lvl);
 	}
 
diff --git a/lib/psci/psci_system_off.c b/lib/psci/psci_system_off.c
index 13e9f4a..7cac4e9 100644
--- a/lib/psci/psci_system_off.c
+++ b/lib/psci/psci_system_off.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2014-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -16,14 +16,14 @@
 {
 	psci_print_power_domain_map();
 
-	assert(psci_plat_pm_ops->system_off);
+	assert(psci_plat_pm_ops->system_off != NULL);
 
 	/* Notify the Secure Payload Dispatcher */
-	if (psci_spd_pm && psci_spd_pm->svc_system_off) {
+	if ((psci_spd_pm != NULL) && (psci_spd_pm->svc_system_off != NULL)) {
 		psci_spd_pm->svc_system_off();
 	}
 
-	console_flush();
+	(void) console_flush();
 
 	/* Call the platform specific hook */
 	psci_plat_pm_ops->system_off();
@@ -35,14 +35,14 @@
 {
 	psci_print_power_domain_map();
 
-	assert(psci_plat_pm_ops->system_reset);
+	assert(psci_plat_pm_ops->system_reset != NULL);
 
 	/* Notify the Secure Payload Dispatcher */
-	if (psci_spd_pm && psci_spd_pm->svc_system_reset) {
+	if ((psci_spd_pm != NULL) && (psci_spd_pm->svc_system_reset != NULL)) {
 		psci_spd_pm->svc_system_reset();
 	}
 
-	console_flush();
+	(void) console_flush();
 
 	/* Call the platform specific hook */
 	psci_plat_pm_ops->system_reset();
@@ -50,32 +50,34 @@
 	/* This function does not return. We should never get here */
 }
 
-int psci_system_reset2(uint32_t reset_type, u_register_t cookie)
+u_register_t psci_system_reset2(uint32_t reset_type, u_register_t cookie)
 {
-	int is_vendor;
+	unsigned int is_vendor;
 
 	psci_print_power_domain_map();
 
-	assert(psci_plat_pm_ops->system_reset2);
+	assert(psci_plat_pm_ops->system_reset2 != NULL);
 
-	is_vendor = (reset_type >> PSCI_RESET2_TYPE_VENDOR_SHIFT) & 1;
-	if (!is_vendor) {
+	is_vendor = (reset_type >> PSCI_RESET2_TYPE_VENDOR_SHIFT) & 1U;
+	if (is_vendor == 0U) {
 		/*
 		 * Only WARM_RESET is allowed for architectural type resets.
 		 */
 		if (reset_type != PSCI_RESET2_SYSTEM_WARM_RESET)
-			return PSCI_E_INVALID_PARAMS;
-		if (psci_plat_pm_ops->write_mem_protect &&
-		    psci_plat_pm_ops->write_mem_protect(0) < 0) {
-			return PSCI_E_NOT_SUPPORTED;
+			return (u_register_t) PSCI_E_INVALID_PARAMS;
+		if ((psci_plat_pm_ops->write_mem_protect != NULL) &&
+		    (psci_plat_pm_ops->write_mem_protect(0) < 0)) {
+			return (u_register_t) PSCI_E_NOT_SUPPORTED;
 		}
 	}
 
 	/* Notify the Secure Payload Dispatcher */
-	if (psci_spd_pm && psci_spd_pm->svc_system_reset) {
+	if ((psci_spd_pm != NULL) && (psci_spd_pm->svc_system_reset != NULL)) {
 		psci_spd_pm->svc_system_reset();
 	}
-	console_flush();
+	(void) console_flush();
 
-	return psci_plat_pm_ops->system_reset2(is_vendor, reset_type, cookie);
+	return (u_register_t)
+		psci_plat_pm_ops->system_reset2((int) is_vendor, reset_type,
+						cookie);
 }