Re: [PATCH 1/2] dt-bindings: clk: Add binding for versal clocking wizard

Greg Kroah-Hartman
2022-10-03T14:50:52Z

On Mon, Oct 03, 2022 at 12:41:34PM +0200, Michal Simek wrote:
> Hi again,
>
> On 10/3/22 11:59, Michal Simek wrote:
> > Hi Greg,
> >
> > On 10/3/22 10:16, Greg Kroah-Hartman wrote:
> > > On Mon, Oct 03, 2022 at 10:10:38AM +0200, Krzysztof Kozlowski wrote:
> > > > On 03/10/2022 09:58, Michal Simek wrote:
> > > > >
> > > > >
> > > > > On 10/3/22 09:23, Krzysztof Kozlowski wrote:
> > > > > > On 03/10/2022 09:15, Michal Simek wrote:
> > > > > > > > > And this is new IP. Not sure who has chosen similar name but this targets
> > > > > > > > > Xilinx Versal SOCs. Origin one was targeting previous families.
> > > > > > > >
> > > > > > > > Do we need a whole new schema doc?
> > > > > > >
> > > > > > > It is completely new IP with different logic compare to origin one.
> > > > > > >
> > > > > > > >
> > > > > > > > It is not ideal to define the same property, xlnx,nr-outputs, more than
> > > > > > > > once. And it's only a new compatible string.
> > > > > > >
> > > > > > > I can't see any issue with using dt binding for xlnx,clocking-wizard.yaml
> > > > > > >
> > > > > > > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/Documentation/devicetree/bindings/clock/xlnx,clocking-wizard.yaml
> > > > > > >
> > > > > >
> > > > > > So we already have out of staging document:
> > > > > > devicetree/bindings/clock/xlnx,clocking-wizard.yaml
> > > > >
> > > > > in 6.1 yes.
> > > > >
> > > > > >
> > > > > > and author wants to add one more:
> > > > > > devicetree/bindings/clock/xlnx,clk-wizard.yaml
> > > > >
> > > > > as I said it is completely different IP which requires
> > > > > complete different driver
> > > > > but IP designers choose similar name which is out of developer control.
> > > > >
> > > > > >
> > > > > > Shall we expect in two years, a third document like:
> > > > > > devicetree/bindings/clock/xlnx,clk-wzrd.yaml
> > > > > > ?
> > > > >
> > > > > Developer definitely doesn't know. If new SoC requires for the same purpose
> > > > > different IP with completely different driver is something out of developer
> > > > > control. As of today I am not aware about such a requirement and need and
> > > > > personally I can just hope that if they need to do such a change they will be
> > > > > able to keep current SW driver compatible with new HW IP.
> > > >
> > > > Then please start naming them reasonable, not two (and in future
> > > > x-times) the same names for entirely different blocks. And by name I
> > > > mean compatible, filename and device name.
> > > >
> > > > > > > also for this IP if that's fine with you.
> > > > > > > Only xlnx,speed-grade can be defined for previous IP which is easy to mark.
> > > > > >
> > > > > > That old binding also explained nr-outputs as "Number of outputs".
> > > > > > Perfect... :(
> > > > >
> > > > > Anyway if description should be improved let's just do it. I just want to get
> > > > > guidance if we should update current dt binding for similar IP or just create
> > > > > new one as this one is trying to do.
> > > >
> > > > IMHO, new binding is extremely confusing. We already have support for
> > > > devices named "xlnx,clocking-wizard" and now you add exactly the same
> > > > (clk=clocking) with almost the same properties, named
> > > > "xlnx,clk-wizard-1.0". For a different IP?
> > > >
> > > > How anyone (even Xilinx' customer) can understand which block is for
> > > > what if they have exactly the same name and (almost) the same
> > > > properties, but as you said - these are entirely different IP?
> > >
> > > Maybe we should just delete the staging one (and the staging driver),
> > > and start over?  No one has taken the time to get the staging driver out
> > > of there, so I have no objection to dropping it for 6.1.
> >
> > As I said it is be out of staging in linux-next. When CLK tree is merged
> > in these 2 weeks we are done at least with this driver.
>
> FYI: Here is link where I asked you for your ACK to get the driver out of staging.
> https://lore.kernel.org/all/Ys%2F%2FaPLkLGaooYYw@kroah.com/

Ah, good, I forgot about that, nevermind!

greg k-h