Re: [PATCH v2 13/23] coresight: trbe: Simplify wrap status handling

[James Clark <james.clark@linaro.org>]

On 16/10/2026 17:55, Leo Yan wrote:
> After explicitly decoding the TRBSR_EL1 EC/BSC values, unsupported or
> unexpected stop reasons are handled before the WRAP check. And the
> erratum and pointer checks is no longer relevant when deciding the
> buffer wrap.
> 
> Remove the redundant checks and treat any remaining TRBSR_EL1.WRAP
> status as a wrap event. This also means WRAP with BSC_NOT_STOPPED is
> reported as an overflow instead of a spurious event, which prepares for
> for TRBE wrap mode where collection continues and a maintenance
> interrupt is raised on current write pointer wrap.
> 
> Signed-off-by: Leo Yan <leo.yan@arm.com>
> ---
>   drivers/hwtracing/coresight/coresight-trbe.c | 11 +----------
>   1 file changed, 1 insertion(+), 10 deletions(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c
> index a851f09d806a6b6a6386d6f7547b01a17f61b88e..4aeed1a17c4bf1653fb41731ac15f31feec7ed2e 100644
> --- a/drivers/hwtracing/coresight/coresight-trbe.c
> +++ b/drivers/hwtracing/coresight/coresight-trbe.c
> @@ -661,8 +661,6 @@ static enum trbe_fault_action trbe_get_fault_act(struct perf_output_handle *hand
>   	const char *err_str;
>   	int ec = get_trbe_ec(trbsr);
>   	int bsc = get_trbe_bsc(trbsr);
> -	struct trbe_buf *buf = etm_perf_sink_config(handle);
> -	struct trbe_cpudata *cpudata = buf->cpudata;
>   
>   	WARN_ON(is_trbe_running(trbsr));
>   
> @@ -710,14 +708,7 @@ static enum trbe_fault_action trbe_get_fault_act(struct perf_output_handle *hand
>   		goto out_fatal;
>   	}
>   
> -	/*
> -	 * If the trbe is affected by TRBE_WORKAROUND_OVERWRITE_FILL_MODE,
> -	 * it might write data after a WRAP event in the fill mode.
> -	 * Thus the check TRBPTR == TRBBASER will not be honored.
> -	 */
> -	if ((is_trbe_wrap(trbsr) && (ec == TRBSR_EL1_EC_OTHER) && (bsc == TRBSR_EL1_BSC_FILLED)) &&
> -	    (trbe_may_overwrite_in_fill_mode(cpudata) ||
> -	     get_trbe_write_pointer() == get_trbe_base_pointer()))
> +	if (is_trbe_wrap(trbsr))
>   		return TRBE_FAULT_ACT_WRAP;
>   
>   	return TRBE_FAULT_ACT_SPURIOUS;
> 
Reviewed-by: James Clark <james.clark@linaro.org>