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Date: Thu, 20 Nov 2025 14:25:20 +0000
From: Leo Yan <leo.yan@arm.com>
To: James Clark <james.clark@linaro.org>,
	Mike Leach <mike.leach@linaro.org>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
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Subject: Re: [PATCH v5 03/13] coresight: Refactor
 etm4_config_timestamp_event()
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References: <20251118-james-cs-syncfreq-v5-0-82efd7b1a751@linaro.org>
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On Thu, Nov 20, 2025 at 02:18:21PM +0000, Coresight ML wrote:

[...]

> Maybe define a general macro but with extra checking:
> 
>   #define TRCCNTCTLRn_RLDEVENT_MASK  GENMASK(15, 8)
> 
>   #define ETM4_RS_SEL_EVENT(paired, sel) ({  \
>       if (paired)                            \
>           assert(!(sel & ~GENMASK(3, 0)));   \
>       else                                   \
>           assert(!(sel & ~GENMASK(4, 0)));   \
>       FIELD_PREP(TRCCNTCTLRn_RLDEVENT_MASK,  \
>                  ((paird << 7) | sel));      \
>   })

It'd be better to use BUILD_BUG_ON() instead of assert().