Re: [PATCH v7 6/9] interconnect: qcom: rpm: Handle interface clocks

[Bryan O'Donoghue]

On 11/03/2023 14:01, Dmitry Baryshkov wrote:
> > Limit the number of bus_clocks to 2 (which is the maximum that SMD
> > RPM interconnect supports anyway) and handle non-scaling clocks
> > separately. Update MSM8996 and SDM660 drivers to make sure they do
> > not regress with this change.
> >
> > This unfortunately has to be done in one patch to prevent either
> > compile errors or broken bisect.
>
> Can we determine somehow if the intf clocks are required for the whole 
> NoC or just for a single node? I don't think that clocks like a0noc_ufs 
> are requiered to be up for the whole aggre_noc. Instead they probably 
> have to be enabled only when UFS makes use of the NoC (in other words 
> when is has voted for the bandwidth).

Its probably worthwhile experimenting to see if the *ufs*_clk can/should 
be added to the UFS device list of clocks.

I hadn't realised we were talking about enabling the intf clocks always 
but, actually that is what we are talking about isn't it ?

It seems pretty unlikely that other devices would depend on clocks named 
*ufs*

OTOH "clk-aggre2-noc-clk-no-rate" may be used across different nodes, 
seems like a pretty generic name, though still suspicious it is bundled 
with UFS, likely it is only required for UFS ?!?

Konrad can you try:

1. Moving the intf_clks/QoS clocks be contained to UFS alone ?
2. If that doesn't work just the *ufs* clocks be put there with
2a. "clk-aggre2-noc-clk-no-rate" alone added to the intf_clk list

It seems wrong to be enabling ufs related NoC clocks unless we are 
actually switching on UFS.

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bod