[PATCH v2 2/9] perf cs-etm: Initialise architecture based on TRCIDR1

[Suzuki K Poulose]

On 06/08/2021 14:41, James Clark wrote:
> Currently the architecture is hard coded as ARCH_V8, but from ETMv4.4
> onwards this should be ARCH_AA64.
> 
> Signed-off-by: James Clark <james.clark at arm.com>
> ---
>   tools/perf/util/cs-etm-decoder/cs-etm-decoder.c | 16 +++++++++++++++-
>   1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> index 187c038caa19..787b19642e78 100644
> --- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> +++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> @@ -126,6 +126,20 @@ static int cs_etm_decoder__gen_etmv3_config(struct cs_etm_trace_params *params,
>   	return 0;
>   }
>   
> +#define TRCIDR1_TRCARCHMIN_SHIFT 4
> +#define TRCIDR1_TRCARCHMIN_MASK  GENMASK(7, 4)
> +#define TRCIDR1_TRCARCHMIN(x)    (((x) & TRCIDR1_TRCARCHMIN_MASK) >> TRCIDR1_TRCARCHMIN_SHIFT)

minor nit: Please add a blank line here

> +static enum _ocsd_arch_version cs_etm_decoder__get_etmv4_arch_ver(u32 reg_idr1)
> +{
> +	/*
> +	 * For ETMv4 if the trace minor version is 4 or more then we can assume
> +	 * the architecture is ARCH_AA64 rather than just V8.
> +	 * ARCH_V8 = V8 architecture
> +	 * ARCH_AA64 = Min v8r3 plus additional AA64 PE features

Does this need to be >= 3 then, to be accurate ?

The comment "reads", minimum v8.3 and any additional features.

Otherwise looks good to me.

Suzuki