ARM: 7015/1: ARM errata: Possible cache data corruption with hit-under-miss enabled

This patch is a workaround for the 364296 ARM1136 r0p2 erratum (possible
cache data corruption with hit-under-miss enabled). It sets the
undocumented bit 31 in the auxiliary control register and the FI bit in
the control register, thus disabling hit-under-miss without putting the
processor into full low interrupt latency mode.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 12 insertions, 0 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 5ebc5d922ea1..3269576dbfa8 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1271,6 +1271,18 @@ config ARM_ERRATA_754327
           This workaround defines cpu_relax() as smp_mb(), preventing correctly
           written polling loops from denying visibility of updates to memory.
 
+config ARM_ERRATA_364296
+        bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
+        depends on CPU_V6 && !SMP
+        help
+          This options enables the workaround for the 364296 ARM1136
+          r0p2 erratum (possible cache data corruption with
+          hit-under-miss enabled). It sets the undocumented bit 31 in
+          the auxiliary control register and the FI bit in the control
+          register, thus disabling hit-under-miss without putting the
+          processor into full low interrupt latency mode. ARM11MPCore
+          is not affected.
+
 endmenu
 
 source "arch/arm/common/Kconfig"