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| author | Catalin Marinas <catalin.marinas@arm.com> | 2009-04-30 17:06:20 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2009-04-30 20:13:00 +0100 |
| commit | 0516e4643cd22fc9f535aef02ad1de66c382c93b (patch) | |
| tree | 8b82945aa5f1ef825656aed2580cacafcd829ac3 | |
| parent | 855c551f5b8cc3815d58e1056c1f1e7c461e2d24 (diff) | |
[ARM] 5489/1: ARM errata: Data written to the L2 cache can be overwritten with stale data
This patch is a workaround for the 460075 Cortex-A8 (r2p0) erratum. It
configures the L2 cache auxiliary control register so that the Write
Allocate mode for the L2 cache is disabled.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| -rw-r--r-- | arch/arm/Kconfig | 12 | ||||
| -rw-r--r-- | arch/arm/mm/proc-v7.S | 5 |
2 files changed, 17 insertions, 0 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 49f85664083..9faccc411c2 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -778,6 +778,18 @@ config ARM_ERRATA_458693 in the ACTLR register. Note that setting specific bits in the ACTLR register may not be available in non-secure mode. +config ARM_ERRATA_460075 + bool "ARM errata: Data written to the L2 cache can be overwritten with stale data" + depends on CPU_V7 + help + This option enables the workaround for the 460075 Cortex-A8 (r2p0) + erratum. Any asynchronous access to the L2 cache may encounter a + situation in which recent store transactions to the L2 cache are lost + and overwritten with stale memory contents from external memory. The + workaround disables the write-allocate mode for the L2 cache via the + ACTLR register. Note that setting specific bits in the ACTLR register + may not be available in non-secure mode. + endmenu source "arch/arm/common/Kconfig" diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index 370baa7a0f0..f2305441e7d 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -194,6 +194,11 @@ __v7_setup: orr r10, r10, #(1 << 9) @ set PLDNOP to 1 mcr p15, 0, r10, c1, c0, 1 @ write aux control register #endif +#ifdef CONFIG_ARM_ERRATA_460075 + mrc p15, 1, r10, c9, c0, 2 @ read L2 cache aux ctrl register + orr r10, r10, #(1 << 22) @ set the Write Allocate disable bit + mcr p15, 1, r10, c9, c0, 2 @ write the L2 cache aux ctrl register +#endif mov r10, #0 #ifdef HARVARD_CACHE mcr p15, 0, r10, c7, c5, 0 @ I+BTB cache invalidate |