[PATCH v4 1/2] dt-bindings: i3c: Add adi-i3c-master

[Conor Dooley]

On Wed, Jul 02, 2025 at 12:58:00PM +0200, Jorge Marques wrote:
> On Fri, Jun 27, 2025 at 06:02:26PM +0200, Jorge Marques wrote:
> > On Fri, Jun 27, 2025 at 04:49:19PM +0200, Krzysztof Kozlowski wrote:
> > > On 27/06/2025 16:38, Jorge Marques wrote:
> > > > On Fri, Jun 27, 2025 at 08:56:55AM +0200, Krzysztof Kozlowski wrote:
> > > >> On Thu, Jun 26, 2025 at 12:07:36PM +0200, Jorge Marques wrote:
> > > >>> Add bindings doc for ADI I3C Controller IP core, a FPGA synthesizable IP
> > > >>> core that implements the MIPI I3C Basic controller specification.
> > > >>
> > > >> How did you resolve my last comment? I don't see any explanation -
> > > >> neither here nor in the binding description. Binding description is
> > > >> actually better place, I think now.
> > > >>
> > > >> Best regards,
> > > >> Krzysztof
> > > >>
> > > > 
> > > > Hi Krzysztof,
> > > > 
> > > > I forgot to condense out discussion on v4.
> > > > What about this binding description:
> > > > 
> > > >   description: |
> > > >     FPGA-based I3C controller designed to interface with I3C and I2C
> > > >     peripherals, implementing a subset of the I3C-basic specification.
> > > >     The IP core is tested on arm, microblaze, and arm64 architectures.
> > > >     It takes one or two clocks, axi and i3c. If only axi is provided,
> > > >     then there is no clock signal to the i3c input clock pin and axi
> > > 
> > > This is obvious from the schema, drop.
> > Ack.
> > 
> > > 
> > > >     clock drives the whole IP. The compatible is suffixed by 1.00.a
> > > >     foreseeing future controllers by Analog Devices Inc. and breaking
> > > >     changes.
> > > 
> > > I don't understand that. How are you breaking any changes? And how
> > > 1.00.a predicts future? I don't think this reflects previous discussion.
> > > Why you were asked to go with v1.00.a?
> > The -1.00.a suffix came from this discussion:
> >   
> >   https://lore.kernel.org/linux-i3c/ildi2pup2zkyv4stuknkrjysex3yzsbrrsrwbgcc4xgvdhwrdd@7qh4y6mutgy2/
> > 
> > Other adi bindings use this suffix. I personally wouldn't add any suffix
> > unless told otherwise, as I expressed on the thread. Should I drop it?
> > or suffix it with something else?

> 
> I went after the reason of the historically -1.00.a suffix and
> discovered that they came into existence due to AMD Xilinx auto
> generation devicetree tool SDTGen
> https://github.com/Xilinx/system-device-tree-xlnx
> that would automatically suffix with the IP version, defaulting to 1.00.a,
> and for a seamless experience, the were copied over to the dt-bindings.
> 
> The adi,axi-pwmgen dt-binding went more creative and suffixed with
> -2.00.a, while never enforcing Vivado to yield the devicetree with such
> value (Major version is asserted in the driver through reg access, the
> current core version is v2.1.1)
> 
> Testing on my side (AMD Xilinx Vivado 2024.2), it seems Vivado now
> defaults to 1.0, so the previous bindings from the other IPs are not
> accurate anymore, either, (axi-pwmgen auto gens
> `compatible = "xlnx,axi-pwm-gen-1.0";` (`xlnx` instead of `adi`, also)).
> 
> For fun, the current Vivado version thinks the devicetree node for the
> i3c master should be as follows:
> 
>   i3c_host_interface: i3c_controller_host_interface at 44a00000 {
>           compatible = "xlnx,i3c-controller-host-interface-1.0";
>           reg = <0x44a00000 0x10000>;
>           clocks = <&clkc 15>;
>           clock-names = "s_axi_aclk";
>   };
> 
> Let me know if we can drop the suffix, or replace with something else.
> The current register defined core version is v0.1.0.

Please, as I requested in the original thread, add versioning
information. I'm clearly not asking you to make up some garbage version
number, or to add "1.00a" if that's not an accurate version (and never
did AFAICT). If 0.1.0 is the version of the IP core, I'd like you to use
that.

If other ADI IP cores are using crap version numbers that came from
some Xilinx tooling that don't represent the actual versions of the IPs,
that's probably something you should mention to your colleagues that
maintain those bindings.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 228 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-i3c/attachments/20250702/2b126f71/attachment-0001.sig>