Re: [PATCH v2 3/3] clk: meson: a1: add support for Amlogic A1 clock driver

[Jian Hu]

On 2019/11/25 20:30, Jerome Brunet wrote:
> On Mon 25 Nov 2019 at 13:01, Jian Hu <jian.hu@xxxxxxxxxxx> wrote:
>
> > On 2019/11/25 18:14, Jerome Brunet wrote:
> > > On Thu 21 Nov 2019 at 04:21, Jian Hu <jian.hu@xxxxxxxxxxx> wrote:
> > >
> > > > Hi, Jerome
> > > >
> > > > On 2019/11/20 23:35, Jerome Brunet wrote:
> > > > > On Wed 20 Nov 2019 at 10:28, Jian Hu <jian.hu@xxxxxxxxxxx> wrote:
> > > > >
> > > > > > Hi, jerome
> > > > > >
> > > > > > Is there any problem about fixed_pll_dco's parent_data?
> > > > > >
> > > > > > Now both name and fw_name are described in parent_data.
> > > > >
> > > > > Yes, there is a problem.  This approach is incorrect, as I've tried to
> > > > > explain a couple times already. Let me try to re-summarize why this
> > > > > approach is incorrect.
> > > > >
> > > > > Both fw_name and name should be provided when it is possible that
> > > > > the DT does not describe the input clock. IOW, it is only for controllers
> > > > > which relied on the global name so far and are now starting to describe
> > > > > the clock input in DT
> > > > >
> > > > > This is not your case.
> > > > > Your controller is new and DT will have the correct
> > > > > info
> > > > >
> > > > > You are trying work around an ordering issue by providing both fw_name
> > > > > and name. This is not correct and I'll continue to nack it.
> > > > >
> > > > > If the orphan clock is not reparented as you would expect, I suggest you
> > > > > try to look a bit further at how the reparenting of orphans is done in
> > > > > CCF and why it does not match your expectation.
> > > > I have debugged the handle for orphan clock in CCF, Maybe you are missing
> > > > the last email.
> > >
> > > Nope, got it the first time
> > >
> > > > Even though the clock index exit, it will get failed for the orphan clock's
> > > > parent clock due to it has not beed added to the provider.
> > >
> > > If the provider is not registered yet, of course any query to it won't
> > > work. This why I have suggested to this debug *further* :
> > >
> > > * Is the orphan reparenting done when a new provider is registered ?
> > > * If not, should it be done ? is this your problem ?
>
> Apparently, I was not clear enough so I'll rephrase
>
> > Yes, the orphan reparenting is done when the new provider is
> > registered.
>
> No it is not done yet. Please check the code.
>
> The reparenting of orphan is done only on clock registration, not on
> provider registeration. Now that clocks can be specified by DT, this
> probably needs to added.The action of reparenting the orphan is before the provider registration 
with the current code.
> That is your problem.
Yes, if the provider is registered before the clock registration, it
will reparent successfully.
> Please fix the underlying issue, then you can post your series again.
>
> > Reparenting the orphan will be done when each clock is registered by
> > devm_clk_hw_register. And at this time the provider has not been
> > registered. After all clocks are registered by devm_clk_hw_register, the
> > provider will be registered by devm_of_clk_add_hw_provider.
> >
> > Reparenting the orphan will fail when fw_name is added alone, the couse is
> > that devm_clk_hw_register is always running ahead of
> > devm_of_clk_add_hw_provider.
>
> Please stop bringing the topic of "fw_name" and "name" field together, I
> told you 3 times why this is wrong. It is not going to change.
>
> > That is why it will failed to get parent for the orphan clock.
>
> It fails because the provider is not registered when you try to reparent
> the orphan.
>
> It shows that you should try again once the provider is registered.
OK, I have exchanged the position for devm_clk_hw_register and 
devm_of_clk_add_hw_provider in meson-eeclk.c.

It reparents successfully for orphan clock.

Is is ok that put devm_of_clk_add_hw_provider ahead?

As far as I am concerned, there is no any effect.
> > > .
>
> .