2 files changed, 13 insertions, 0 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 2f88d8d97701..48c19d44be9a 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1413,6 +1413,16 @@ config PL310_ERRATA_769419
           on systems with an outer cache, the store buffer is drained
           explicitly.
 
+config ARM_ERRATA_775420
+       bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
+       depends on CPU_V7
+       help
+         This option enables the workaround for the 775420 Cortex-A9 (r2p2,
+         r2p6,r2p8,r2p10,r3p0) erratum. In case a date cache maintenance
+         operation aborts with MMU exception, it might cause the processor
+         to deadlock. This workaround puts DSB before executing ISB if
+         an abort may occur on cache maintenance.
+
 endmenu
 
 source "arch/arm/common/Kconfig"
diff --git a/arch/arm/mm/cache-v7.S b/arch/arm/mm/cache-v7.S
index 39e3fb3db801..3b172275262e 100644
--- a/arch/arm/mm/cache-v7.S
+++ b/arch/arm/mm/cache-v7.S
@@ -211,6 +211,9 @@ ENTRY(v7_coherent_user_range)
  * isn't mapped, fail with -EFAULT.
  */
 9001:
+#ifdef CONFIG_ARM_ERRATA_775420
+        dsb
+#endif
         mov     r0, #-EFAULT
         mov     pc, lr
  UNWIND(.fnend          )