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    SubjectRe: [PATCH v7 6/9] interconnect: qcom: rpm: Handle interface clocks
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    On 21.03.2023 14:58, Georgi Djakov wrote:
    > Hi,
    >
    > On 11.03.23 17:26, Dmitry Baryshkov wrote:
    >> On 11/03/2023 16:38, Bryan O'Donoghue wrote:
    >>> On 11/03/2023 14:35, Dmitry Baryshkov wrote:
    >>>>> Its probably worthwhile experimenting to see if the*ufs*_clk can/should
    >>>>> be added to the UFS device list of clocks.
    >>>> While we were doing this for some of the clocks (PCIe and USB, if I'm
    >>>> not mistaken), I think that generally this is not fully correct. In my
    >>>> opinion it should be in the interconnect driver, who turns
    >>>> corresponding clocks on and off. These clocks correspond to the SoC
    >>>> topology, rather than the end-device.
    >>>>
    >>>
    >>> True enough, they are interconnect clocks.
    >>>
    >>> The question is how to only turn them on when the device that depends on them wants them.
    >>
    >> I think we can turn them on an off from qcom_icc_set(). Each node can list required clocks.
    >>
    >
    > Yes, this is a bit weird, but looks like these are the interface clocks
    > required for programming the qos box of the respective peripheral and
    > nothing else. Maybe we can even configure QoS just once (eg. on the first
    > bandwidth request) and not every time we call qcom_icc_set().
    Would that persist a full bus reset - if we e.g. shut down MMNoC
    after the display stack is turned off in preparation for a power
    collapse, would we have to reprogram it?

    Another thing is, do we know "how persistent" the QoS settings are?
    What could reset them? Would a bandwidth request for a node that
    belongs to the same path do so?

    Konrad
    >
    > BR,
    > Georgi

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