From 7253b85cc62d6ff84143d96fe6cd54f73736f4d7 Mon Sep 17 00:00:00 2001 From: Simon Horman Date: Fri, 28 Sep 2012 02:12:45 +0100 Subject: [PATCH] ARM: 7541/1: Add ARM ERRATA 775420 workaround arm: Add ARM ERRATA 775420 workaround 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. Based on work by Kouei Abe and feedback from Catalin Marinas. Signed-off-by: Kouei Abe [ horms@verge.net.au: Changed to implementation suggested by catalin.marinas@arm.com ] Acked-by: Catalin Marinas Signed-off-by: Simon Horman Signed-off-by: Russell King --- arch/arm/Kconfig | 10 ++++++++++ arch/arm/mm/cache-v7.S | 3 +++ 2 files changed, 13 insertions(+) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 2f88d8d..48c19d4 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 39e3fb3..3b17227 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 ) -- 2.7.4