Re: [PATCH v4 02/15] arm64: errata: Add detection for TRBE overwrite in FILL mode

[Randy Dunlap]

Hi,

On 10/12/21 6:17 AM, Suzuki K Poulose wrote:
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 077f2ec4eeb2..404f56e87e93 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -666,6 +666,47 @@ config ARM64_ERRATUM_1508412
>   
>   	  If unsure, say Y.
>   
> +config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
> +	bool
> +
> +config ARM64_ERRATUM_2119858
> +	bool "Cortex-A710: 2119858: workaround TRBE overwriting trace data in FILL mode"
> +	default y
> +	depends on COMPILE_TEST # Until the CoreSight TRBE driver changes are in
> +	depends on CORESIGHT_TRBE
> +	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
> +	help
> +	  This option adds the workaround for ARM Cortex-A710 erratum 2119858.
> +
> +	  Affected Cortex-A710 cores could overwrite upto 3 cache lines of trace

	                                             up to

> +	  data at the base of the buffer (ponited by TRBASER_EL1) in FILL mode in

	                                  pointed to by

> +	  the event of a WRAP event.
> +
> +	  Work around the issue by always making sure we move the TRBPTR_EL1 by
> +	  256bytes before enabling the buffer and filling the first 256bytes of

	  256 bytes                                                 256 bytes

> +	  the buffer with ETM ignore packets upon disabling.
> +
> +	  If unsure, say Y.
> +
> +config ARM64_ERRATUM_2139208
> +	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
> +	default y
> +	depends on COMPILE_TEST # Until the CoreSight TRBE driver changes are in
> +	depends on CORESIGHT_TRBE
> +	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
> +	help
> +	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
> +
> +	  Affected Neoverse-N2 cores could overwrite upto 3 cache lines of trace

	                                             up to

> +	  data at the base of the buffer (ponited by TRBASER_EL1) in FILL mode in

	                                  pointed to by

> +	  the event of a WRAP event.
> +
> +	  Work around the issue by always making sure we move the TRBPTR_EL1 by
> +	  256bytes before enabling the buffer and filling the first 256bytes of

	  256 bytes                                                 256 bytes

> +	  the buffer with ETM ignore packets upon disabling.
> +
> +	  If unsure, say Y.


--
~Randy