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authorCatalin Marinas <catalin.marinas@arm.com>2009-04-30 18:06:09 +0200
committerRussell King <rmk+kernel@arm.linux.org.uk>2009-04-30 21:12:50 +0200
commit7ce236fcd6fd45b0441a2d49acb2ceb2de2e8a47 (patch)
tree1f092413fbe0c91350e7861638dec7bb475c8435 /arch/arm/Kconfig
parent[ARM] 5488/1: ARM errata: Invalidation of the Instruction Cache operation can... (diff)
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[ARM] 5487/1: ARM errata: Stale prediction on replaced interworking branch
This patch adds the workaround for the 430973 Cortex-A8 (r1p0..r1p2) erratum. The BTAC/BTB is now flushed at every context switch. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/Kconfig')
-rw-r--r--arch/arm/Kconfig16
1 files changed, 16 insertions, 0 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index e28a76bd1793..84e4816362b3 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -749,6 +749,22 @@ config ARM_ERRATA_411920
It does not affect the MPCore. This option enables the ARM Ltd.
recommended workaround.
+config ARM_ERRATA_430973
+ bool "ARM errata: Stale prediction on replaced interworking branch"
+ depends on CPU_V7
+ help
+ This option enables the workaround for the 430973 Cortex-A8
+ (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
+ interworking branch is replaced with another code sequence at the
+ same virtual address, whether due to self-modifying code or virtual
+ to physical address re-mapping, Cortex-A8 does not recover from the
+ stale interworking branch prediction. This results in Cortex-A8
+ executing the new code sequence in the incorrect ARM or Thumb state.
+ The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
+ and also flushes the branch target cache at every context switch.
+ Note that setting specific bits in the ACTLR register may not be
+ available in non-secure mode.
+
endmenu
source "arch/arm/common/Kconfig"