diff --git a/plat/arm/common/arm_nor_psci_mem_protect.c b/plat/arm/common/arm_nor_psci_mem_protect.c
index c01e4ed..1b0b1da 100644
--- a/plat/arm/common/arm_nor_psci_mem_protect.c
+++ b/plat/arm/common/arm_nor_psci_mem_protect.c
@@ -51,14 +51,14 @@
  ******************************************************************************/
 int arm_nor_psci_write_mem_protect(int val)
 {
-	int enable = (val != 0);
+	int enable = (val != 0) ? 1 : 0;
 
 	if (nor_unlock(PLAT_ARM_MEM_PROT_ADDR) != 0) {
 		ERROR("unlocking memory protect variable\n");
 		return -1;
 	}
 
-	if (enable != 0) {
+	if (enable == 1) {
 		/*
 		 * If we want to write a value different than 0
 		 * then we have to erase the full block because
@@ -117,14 +117,14 @@
 {
 	int enable;
 
-	arm_psci_read_mem_protect(&enable);
+	(void) arm_psci_read_mem_protect(&enable);
 	if (enable == 0)
 		return;
 
 	INFO("PSCI: Overwriting non secure memory\n");
 	clear_mem_regions(arm_ram_ranges,
 			  ARRAY_SIZE(arm_ram_ranges));
-	arm_nor_psci_write_mem_protect(0);
+	(void) arm_nor_psci_write_mem_protect(0);
 }
 
 /*******************************************************************************
diff --git a/plat/arm/common/arm_pm.c b/plat/arm/common/arm_pm.c
index d0350d6..a8289ff 100644
--- a/plat/arm/common/arm_pm.c
+++ b/plat/arm/common/arm_pm.c
@@ -30,11 +30,11 @@
 int arm_validate_power_state(unsigned int power_state,
 			    psci_power_state_t *req_state)
 {
-	int pstate = psci_get_pstate_type(power_state);
-	int pwr_lvl = psci_get_pstate_pwrlvl(power_state);
-	int i;
+	unsigned int pstate = psci_get_pstate_type(power_state);
+	unsigned int pwr_lvl = psci_get_pstate_pwrlvl(power_state);
+	unsigned int i;
 
-	assert(req_state);
+	assert(req_state > 0U);
 
 	if (pwr_lvl > PLAT_MAX_PWR_LVL)
 		return PSCI_E_INVALID_PARAMS;
@@ -59,7 +59,7 @@
 	/*
 	 * We expect the 'state id' to be zero.
 	 */
-	if (psci_get_pstate_id(power_state))
+	if (psci_get_pstate_id(power_state) != 0U)
 		return PSCI_E_INVALID_PARAMS;
 
 	return PSCI_E_SUCCESS;
diff --git a/plat/common/plat_psci_common.c b/plat/common/plat_psci_common.c
index 6c5cd55..fab3c77 100644
--- a/plat/common/plat_psci_common.c
+++ b/plat/common/plat_psci_common.c
@@ -67,7 +67,7 @@
 void plat_psci_stat_accounting_start(
 	__unused const psci_power_state_t *state_info)
 {
-	assert(state_info);
+	assert(state_info != NULL);
 	PMF_CAPTURE_TIMESTAMP(psci_svc, PSCI_STAT_ID_ENTER_LOW_PWR,
 		PMF_NO_CACHE_MAINT);
 }
@@ -80,7 +80,7 @@
 void plat_psci_stat_accounting_stop(
 	__unused const psci_power_state_t *state_info)
 {
-	assert(state_info);
+	assert(state_info != NULL);
 	PMF_CAPTURE_TIMESTAMP(psci_svc, PSCI_STAT_ID_EXIT_LOW_PWR,
 		PMF_NO_CACHE_MAINT);
 }
@@ -97,12 +97,12 @@
 	unsigned long long pwrup_ts = 0, pwrdn_ts = 0;
 	unsigned int pmf_flags;
 
-	assert(lvl >= PSCI_CPU_PWR_LVL && lvl <= PLAT_MAX_PWR_LVL);
-	assert(state_info);
-	assert(last_cpu_idx >= 0 && last_cpu_idx <= PLATFORM_CORE_COUNT);
+	assert((lvl >= PSCI_CPU_PWR_LVL) && (lvl <= PLAT_MAX_PWR_LVL));
+	assert(state_info != NULL);
+	assert(last_cpu_idx <= PLATFORM_CORE_COUNT);
 
 	if (lvl == PSCI_CPU_PWR_LVL)
-		assert(last_cpu_idx == plat_my_core_pos());
+		assert((unsigned int)last_cpu_idx == plat_my_core_pos());
 
 	/*
 	 * If power down is requested, then timestamp capture will
@@ -110,10 +110,10 @@
 	 * when reading the timestamp.
 	 */
 	state = state_info->pwr_domain_state[PSCI_CPU_PWR_LVL];
-	if (is_local_state_off(state)) {
+	if (is_local_state_off(state) != 0) {
 		pmf_flags = PMF_CACHE_MAINT;
 	} else {
-		assert(is_local_state_retn(state));
+		assert(is_local_state_retn(state) == 1);
 		pmf_flags = PMF_NO_CACHE_MAINT;
 	}
 
@@ -150,14 +150,18 @@
 					     unsigned int ncpu)
 {
 	plat_local_state_t target = PLAT_MAX_OFF_STATE, temp;
+	const plat_local_state_t *st = states;
+	unsigned int n = ncpu;
 
-	assert(ncpu);
+	assert(ncpu > 0U);
 
 	do {
-		temp = *states++;
+		temp = *st;
+		st++;
 		if (temp < target)
 			target = temp;
-	} while (--ncpu);
+		n--;
+	} while (n > 0U);
 
 	return target;
 }