Re: [PATCH] soc: qcom: llcc: Fix dis_cap_alloc and retain_on_pc configuration

[Mukesh Ojha]

On 11/7/2023 3:25 AM, Stephen Boyd wrote:
> 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?

@Atul will update the commit text as per suggestion.

And yes, without this change, retention feature will not work properly.

-Mukesh