diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
index 8013afc..fc5b36f 100644
--- a/arch/arm/mm/proc-v7.S
+++ b/arch/arm/mm/proc-v7.S
@@ -166,7 +166,9 @@ ENTRY(cpu_v7_set_pte_ext)
  ARM(	str	r3, [r0, #2048]! )
  THUMB(	add	r0, r0, #2048 )
  THUMB(	str	r3, [r0] )
-	mcr	p15, 0, r0, c7, c10, 1		@ flush_pte
+	mrc	p15, 0, r3, c0, c1, 7		@ read ID_MMFR3
+	tst	r3, #0xf << 20			@ check the coherent walk bits
+	mcreq	p15, 0, r0, c7, c10, 1		@ flush_pte
 #endif
 	mov	pc, lr
 ENDPROC(cpu_v7_set_pte_ext)