Re: [PATCH 0/2] fdt: translate address if #size-cells = <0>

[Tero Kristo]

On 07/04/2021 15:52, Rob Herring wrote:
> On Wed, Apr 7, 2021 at 2:07 AM Dario Binacchi <dariobin@xxxxxxxxx> wrote:
> > > Il 07/04/2021 03:16 Rob Herring <robh+dt@xxxxxxxxxx> ha scritto:
> > >
> > >
> > > On Tue, Apr 6, 2021 at 5:02 PM Dario Binacchi <dariobin@xxxxxxxxx> wrote:
> > > > > Il 06/04/2021 16:06 Rob Herring <robh+dt@xxxxxxxxxx> ha scritto:
> > > > >
> > > > >
> > > > > On Fri, Apr 2, 2021 at 2:21 PM Dario Binacchi <dariobin@xxxxxxxxx> wrote:
> > > > > > The series comes from my commit in U-boot
> > > > > > d64b9cdcd4 ("fdt: translate address if #size-cells = <0>")
> > > > > > and from the subsequent exchange of emails at the end of which I was
> > > > > > suggested to send the patch to the linux kernel
> > > > > > (https://patchwork.ozlabs.org/project/uboot/patch/1614324949-61314-1-git-send-email-bmeng.cn@xxxxxxxxx/).
> > > > >
> > > > > It's 'ranges' that determines translatable which is missing from the
> > > > > DT. This should have not had a 0 size either though maybe we could
> > > > > support that.
> > > >
> > > > I have replied to the email you sent to the u-boot mailing list
> > > >
> > > > > Does the DT have to be updated anyways for your spread spectrum support?
> > > >
> > > > The spread spectrum support patch does not need this patch to work. They belong
> > > > to two different series.
> > >
> > > That's not what I asked. Is the spread spectrum support forcing a DT
> > > update for users?
> >
> > Yes, the deltam and modfreq registers must be added to the DPLL clocks.
>
> That's a shame given this dts has been mostly untouched since 2013.

I think technically it would be possible to map these registers within 
the driver also, seeing there are like a handful of the DPLLs for both 
am3/am4 which are impacted. Just add a new compatible or something, or 
alternatively parse the register addresses and populate the 
deltam/modfreq registers based on that.

> > > If the DT has to be changed anyways (not really
> > > great policy), then you could fix this in the DT at the same time.
> >
> > I could put the fix to the device tree in that series, although I wouldn't
> > create a single patch to fix and add the SSC registers. First the size-cells = <0>
> > fix patch and then the SSC patch.
> > Do you agree?
>
> By at the same time, I really just meant within 1 release.
>
> But I'd like to hear TI maintainers' thoughts on this.

I did post a comment on patch #1 questioning the approach from TI clock 
driver perspective, imho I can't see why these two patches would be 
needed right now.

-Tero