Add core support for ARMv6/v7 big-endian

Starting with ARMv6, the CPUs support the BE-8 variant of big-endian
(byte-invariant). This patch adds the core support:

- setting of the BE-8 mode via the CPSR.E register for both kernel and
  user threads
- big-endian page table walking
- REV used to rotate instructions read from memory during fault
  processing as they are still little-endian format
- Kconfig and Makefile support for BE-8. The --be8 option must be passed
  to the final linking stage to convert the instructions to
  little-endian

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index b55cb033180..366e5097a41 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -210,6 +210,9 @@ ENTRY(vector_swi)
   A710(	teq	ip, #0x0f000000						)
   A710(	bne	.Larm710bug						)
 #endif
+#ifdef CONFIG_CPU_ENDIAN_BE8
+	rev	r10, r10			@ little endian instruction
+#endif
 
 #elif defined(CONFIG_AEABI)