[PATCH v5 04/12] coresight: etm4x: exclude ss_status from drvdata->config

Yeoreum Yun yeoreum.yun at arm.com
Tue Apr 21 03:03:20 PDT 2026


Hi Mike,

> Hi,
>
> This register [bit 31] indicates if a single shot comparator has matched. So
> read-back provides information to the user post run to determine which if
> any of the comparators set in this way has actually matched.

Okay. so after disable sysfs session, to check former session
check whether comprator has matched.

>
> Moreover, the specification states "Software must reset this bit to 0 to
> re-enable single-shot control" and "Reset state is unknown. STATUS must be
> written to set an initial state...."
>
> Therefore this register must be written as part of any configuration so
> should be available in the drvdata->config for both read and write,

But I don't think this is the reason for locate ss_status into "config"
since its write purpose is not to configure but the "clear" former bit.
That's why I think it's enough to clear when the new sysfs session starts.

Am I missing something?

Thanks!

--
Sincerely,
Yeoreum Yun



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