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From:   Stephen Boyd <swboyd@chromium.org>
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Date:   Mon, 6 Nov 2023 13:55:58 -0800
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Subject: Re: [PATCH] soc: qcom: llcc: Fix dis_cap_alloc and retain_on_pc configuration
To:     Atul Dhudase <quic_adhudase@quicinc.com>,
        Bjorn Andersson <quic_bjorande@quicinc.com>,
        Mukesh Ojha <quic_mojha@quicinc.com>
Cc:     agross@kernel.org, andersson@kernel.org, konrad.dybcio@linaro.org,
        isaacm@codeaurora.org, dianders@chromium.org,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org
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Quoting Mukesh Ojha (2023-11-05 22:54:28)
>
>
> On 11/4/2023 1:03 AM, Bjorn Andersson wrote:
> > On Fri, Nov 03, 2023 at 04:27:12PM +0530, Atul Dhudase wrote:
> >> While programming dis_cap_alloc and retain_on_pc, set a bit
> >> corresponding to a specific SCID without disturbing the
> >> previously configured bits.
> >>
> >
> > As far as I can see, the only invocation of _qcom_llcc_cfg_program()
> > comes from qcom_llcc_cfg_program(), which is only called once, from
> > qcom_llcc_probe(), and here also seems to only be the single write to
> > these two registers.
>
> It does not look to be single write but the write is for each slice
> in the same register which was overriding other slices values.

Can you add that detail to the commit text? What's the seriousness of
the issue? Why should it be backported to stable? Is something seriously
broken because a slice configuration is overwritten? Does it mean that
some allocation made in a slice is being lost over power collapse (pc)
when it shouldn't be?