[arch][arm64] Fix barriers in startup code
After a TLBI instruction the right thing to do is to execute DSB
followed by ISB. DSB ensures that the TLBI is seen by all observers of
the system and ISB ensures that the DSB has finished before continuing.
@@ -286,8 +286,8 @@ arm_reset:
/* Invalidate TLB */
tlbi vmalle1is
- isb
dsb sy
+ isb
/* Initialize Memory Attribute Indirection Register */
ldr tmp, =MMU_MAIR_VAL
@@ -331,6 +331,7 @@ arm_reset:
/* Invalidate TLB */
tlbi vmalle1
+ dsb sy
isb
#if WITH_SMP
