arch: arm: use data & instruction barrier before invalidating tlb

Make sure that all the data and instruction fetch are complete before
invalidating the tlbi.

Change-Id: I60ec904f3420fc8215b3b2e9928d505e2f470fb1
diff --git a/arch/arm/ops.S b/arch/arm/ops.S
index 4cfd180..517ade1 100644
--- a/arch/arm/ops.S
+++ b/arch/arm/ops.S
@@ -1,7 +1,7 @@
 /*
  * Copyright (c) 2008 Travis Geiselbrecht
  *
- * Copyright (c) 2014, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2014-2015 The Linux Foundation. All rights reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files
@@ -245,6 +245,8 @@
 
 /* void arm_invalidate_tlb(void) */
 FUNCTION(arm_invalidate_tlb)
+	dsb
+	isb
 	mov		r0, #0
 	mcr	p15, 0, r0, c8, c7, 0
 #if ARM_CPU_CORTEX_A8