Re: [PATCH] coresight: etm4x: Skip setting LPOVERRIDE bit for qcom,skip-power-up

[Sai Prakash Ranjan]

Hi Suzuki,

On 2020-10-16 16:51, Suzuki Poulose wrote:
> Hi Sai,
>
> On 10/16/20 11:10 AM, Sai Prakash Ranjan wrote:
> > There is a bug on the systems supporting to skip power up
> > (qcom,skip-power-up) where setting LPOVERRIDE bit(low-power
> > state override behaviour) will result in CPU hangs/lockups
> > even on the implementations which supports it. So skip
> > setting the LPOVERRIDE bit for such platforms.
> >
> > Fixes: 02510a5aa78d ("coresight: etm4x: Add support to skip trace unit 
> > power up")
> > Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@xxxxxxxxxxxxxx>
>
> The fix is fine by me. Btw, is there a hardware Erratum assigned for
> this ? It would be good to have the Erratum documented somewhere,
> preferrably ( Documentation/arm64/silicon-errata.rst )

No, afaik we don't have any erratum assigned to this bug.
It was already present in downstream kernel and since we
support these targets with the previous HW bug
(qcom,skip-power-up) now in upstream, we would need this
fix in upstream kernel as well.

Thanks,
Sai

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