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    SubjectRe: [PATCH v2 2/4] Documentation: Add documentation for APM X-Gene SoC PMU DTS binding
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    Hi all,

    It's been weeks.
    I just want to ping again if you have any more comments on this patch set?

    Thanks,
    Tai

    On Tue, May 10, 2016 at 4:43 PM, Tai Tri Nguyen <ttnguyen@apm.com> wrote:
    > Hi Rob/Mark,
    >
    > Do you have any more comments, please?
    >
    > Thanks,
    > Tai
    >
    > On Mon, May 2, 2016 at 2:46 PM, Tai Tri Nguyen <ttnguyen@apm.com> wrote:
    >> Hi Rob,
    >>
    >> On Mon, May 2, 2016 at 1:56 PM, Rob Herring <robh@kernel.org> wrote:
    >>> On Wed, Apr 20, 2016 at 12:31:22PM +0100, Will Deacon wrote:
    >>>> On Mon, Apr 18, 2016 at 01:04:53PM -0700, Tai Tri Nguyen wrote:
    >>>> > >> +Required properties for MCB subnode:
    >>>> > >> +- compatible : Shall be "apm,xgene-pmu-mcb".
    >>>> > >> +- reg : First resource shall be the MCB PMU resource.
    >>>> > >> +- index : Instance number of the MCB PMU.
    >>>> > >> +
    >>>> > >> +Required properties for MC subnode:
    >>>> > >> +- compatible : Shall be "apm,xgene-pmu-mc".
    >>>> > >> +- reg : First resource shall be the MC PMU resource.
    >>>> > >> +- index : Instance number of the MC PMU.
    >>>> > >
    >>>> > > Don't use indexes. You probably need phandles to the nodes these are
    >>>> > > related to.
    >>>> > >
    >>>> > > How many variations of child nodes do you expect to have? 2, 10, 50? You
    >>>> > > might want to just collapse all this down to a single node and put this
    >>>> > > information in the driver if it is fixed for each SoC and there's only a
    >>>> > > handful.
    >>>> > >
    >>>> >
    >>>> > For each kind of PMU, for example memory controller PMU, I expect to
    >>>> > have the number of instances up to 8.
    >>>> > They are actually all independent PMU nodes and have their own CSR memory bases.
    >>>> > The indexes are used for exposing the devices to perf user only. It
    >>>> > doesn't have an impact on the programming model.
    >>>> > Mark also had the same concern.
    >>>>
    >>>> Regardless, I'll need an ack from Rob or Mark before I can merge this.
    >>>
    >>> I still have a concern with this. Needing an index to expose to the user
    >>> is generally not a valid reason. That's OS specific and therefore
    >>> doesn't belong in DT.
    >>>
    >>> Rob
    >>
    >> I can use device name here. However, the perf event names will be
    >> different between DT and ACPI which I want to avoid.
    >> And the names don't look good at all.
    >> Also, specifically for MC and MCB PMUs, the indexes are compared
    >> against the active MC/MCB mask to find out whether they are populated
    >> or not.
    >> Without using the index property, I will also need a mapping function
    >> of physical device addresses and their physical ids.
    >>
    >> Thanks,
    >> --
    >> Tai
    >
    >
    >
    > --
    > Tai



    --
    Tai

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