[PATCH 07/10] arm64: Add erratum detection for TRBE overwrite in FILL mode

Catalin Marinas catalin.marinas at arm.com
Mon Aug 2 04:22:35 PDT 2021


On Wed, Jul 28, 2021 at 02:52:14PM +0100, Suzuki K Poulose wrote:
> Arm Neoverse-N2 and the Cortex-A710 cores are affected
> by a CPU erratum where the TRBE will overwrite the trace buffer
> in FILL mode. The TRBE doesn't stop (as expected in FILL mode)
> when it reaches the limit and wraps to the base to continue
> writing upto 3 cache lines. This will overwrite any trace that
> was written previously.
> 
> Add the Neoverse-N2 erratumi(#2139208) and Cortex-A710 erratum
> (#2119858) to the  detection logic.
> 
> This will be used by the TRBE driver in later patches to work
> around the issue. The detection has been kept with the core
> arm64 errata framework list to make sure :
>   - We don't duplicate the framework in TRBE driver
>   - The errata detection is advertised like the rest
>     of the CPU errata.
> 
> Note that the Kconfig entries will be added after we have added
> the work around in the TRBE driver, which depends on the cpucap
> from here.
> 
> Cc: Will Deacon <will at kernel.org>
> Cc: Mark Rutland <mark.rutland at arm.com>
> Cc: Anshuman Khandual <anshuman.khandual at arm.com>
> Cc: Catalin Marinas <catalin.marinas at arm.com>
> Cc: Mathieu Poirier <mathieu.poirier at linaro.org>
> Cc: Mike Leach <mike.leach at linaro.org>
> cc: Leo Yan <leo.yan at linaro.org>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>

Acked-by: Catalin Marinas <catalin.marinas at arm.com>



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