diff --git a/include/bl31/ehf.h b/include/bl31/ehf.h
index 142b4c0..be8c957 100644
--- a/include/bl31/ehf.h
+++ b/include/bl31/ehf.h
@@ -55,6 +55,9 @@
 
 	/* Priority mask value before any priority levels were active */
 	uint8_t init_pri_mask;
+
+	/* Non-secure priority mask value stashed during Secure execution */
+	uint8_t ns_pri_mask;
 } __aligned(sizeof(uint64_t)) pe_exc_data_t;
 
 typedef int (*ehf_handler_t)(uint32_t intr_raw, uint32_t flags, void *handle,
@@ -79,6 +82,8 @@
 void ehf_activate_priority(unsigned int priority);
 void ehf_deactivate_priority(unsigned int priority);
 void ehf_register_priority_handler(unsigned int pri, ehf_handler_t handler);
+void ehf_allow_ns_preemption(void);
+unsigned int ehf_is_ns_preemption_allowed(void);
 
 #endif /* __ASSEMBLY__ */
 
diff --git a/include/drivers/arm/gic_common.h b/include/drivers/arm/gic_common.h
index 9e126a8..efa9703 100644
--- a/include/drivers/arm/gic_common.h
+++ b/include/drivers/arm/gic_common.h
@@ -34,10 +34,10 @@
 #define GIC_INTR_CFG_EDGE		1
 
 /* Constants to categorise priorities */
-#define GIC_HIGHEST_SEC_PRIORITY	0
-#define GIC_LOWEST_SEC_PRIORITY		127
-#define GIC_HIGHEST_NS_PRIORITY		128
-#define GIC_LOWEST_NS_PRIORITY		254 /* 255 would disable an interrupt */
+#define GIC_HIGHEST_SEC_PRIORITY	0x0
+#define GIC_LOWEST_SEC_PRIORITY		0x7f
+#define GIC_HIGHEST_NS_PRIORITY		0x80
+#define GIC_LOWEST_NS_PRIORITY		0xfe /* 0xff would disable all interrupts */
 
 /*******************************************************************************
  * GIC Distributor interface register offsets that are common to GICv3 & GICv2