[ 53/68] ARM: 7345/1: errata: update workaround for A9 erratum #743622
From: Greg KH <gregkh@linuxfoundation.org>
Date: 2012-03-09 19:53:59
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3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Will Deacon <redacted> commit efbc74ace95338484f8d732037b99c7c77098fce upstream. Erratum #743622 affects all r2 variants of the Cortex-A9 processor, so ensure that the workaround is applied regardless of the revision. Reported-by: Russell King <redacted> Signed-off-by: Will Deacon <redacted> Signed-off-by: Russell King <redacted> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- arch/arm/Kconfig | 2 +- arch/arm/mm/proc-v7.S | 4 +--- 2 files changed, 2 insertions(+), 4 deletions(-)
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig@@ -1179,7 +1179,7 @@ config ARM_ERRATA_743622 depends on CPU_V7 help This option enables the workaround for the 743622 Cortex-A9 - (r2p0..r2p2) erratum. Under very rare conditions, a faulty + (r2p*) erratum. Under very rare conditions, a faulty optimisation in the Cortex-A9 Store Buffer may lead to data corruption. This workaround sets a specific bit in the diagnostic register of the Cortex-A9 which disables the Store Buffer --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S
@@ -344,9 +344,7 @@ __v7_setup: mcreq p15, 0, r10, c15, c0, 1 @ write diagnostic register #endif #ifdef CONFIG_ARM_ERRATA_743622 - teq r6, #0x20 @ present in r2p0 - teqne r6, #0x21 @ present in r2p1 - teqne r6, #0x22 @ present in r2p2 + teq r5, #0x00200000 @ only present in r2p* mrceq p15, 0, r10, c15, c0, 1 @ read diagnostic register orreq r10, r10, #1 << 6 @ set bit #6 mcreq p15, 0, r10, c15, c0, 1 @ write diagnostic register