[PATCH v6 02/13] coresight: etm4x: fix underflow for nrseqstate

Leo Yan leo.yan at arm.com
Tue May 5 09:19:05 PDT 2026


On Wed, Apr 22, 2026 at 02:21:52PM +0100, Yeoreum Yun wrote:
> TCRSEQEVR<n> is implemented only when TCRIDR5.NUMSEQSTATE is 0b100,
> in which case n ranges from 0 to 2; otherwise, TCRIDR5.NUMSEQSTATE is 0b000.
> 
> Therefore, drvdata->nrseqstate should be checked before entering the loop.

Since TRCSEQEVRn (n=0~2), to avoid confusion, we also need to rename
ETM_MAX_SEQ_STATES to ETM_MAX_SEQ_TRANSITIONS and define it as 3:

   #define ETM_MAX_SEQ_TRANSITIONS      3

Then we don't allocate 4 items but use only 3 of them.

Thanks,
Leo



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