arm64: gic-v3: Implement arch support for priority masking

Implement architecture specific primitive allowing the GICv3 driver to
use priorities to mask interrupts.
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/include/asm/arch_gicv3.h

@@ -22,6 +22,7 @@
 
 #ifndef __ASSEMBLY__
 
+#include <linux/irqchip/arm-gic-common.h>
 #include <linux/stringify.h>
 #include <asm/barrier.h>
 #include <asm/cacheflush.h>
@@ -162,14 +163,13 @@ static inline bool gic_prio_masking_enabled(void)
 
 static inline void gic_pmr_mask_irqs(void)
 {
-	/* Should not get called yet. */
-	WARN_ON_ONCE(true);
+	BUILD_BUG_ON(GICD_INT_DEF_PRI <= GIC_PRIO_IRQOFF);
+	gic_write_pmr(GIC_PRIO_IRQOFF);
 }
 
 static inline void gic_arch_enable_irqs(void)
 {
-	/* Should not get called yet. */
-	WARN_ON_ONCE(true);
+	asm volatile ("msr daifclr, #2" : : : "memory");
 }
 
 #endif /* __ASSEMBLY__ */