Re: [PATCH v2 2/3] arm64: dts: ti: Introduce J742S2 SoC family

Andrew Davis
2024-07-31T14:38:10Z

On 7/31/24 8:57 AM, Manorit Chawdhry wrote:
> Hi Nishanth,
>
> On 06:06-20240731, Nishanth Menon wrote:
>> On 09:49-20240731, Manorit Chawdhry wrote:
>>>>> + */
>>>>> +
>>>>> +#include "k3-j784s4.dtsi"
>>>>> +
>>>>> +/ {
>>>>> + model = "Texas Instruments K3 J742S2 SoC";
>>>>> + compatible = "ti,j742s2";
>>>>> +
>>>>> + cpus {
>>>>> + cpu-map {
>>>>> + /delete-node/ cluster1;
>>>>> + };
>>>>> + };
>>>>> +
>>>>> + /delete-node/ cpu4;
>>>>> + /delete-node/ cpu5;
>>>>> + /delete-node/ cpu6;
>>>>> + /delete-node/ cpu7;
>>>>
>>>> I suggest refactoring by renaming the dtsi files as common and split out
>>>> j784s4 similar to j722s/am62p rather than using /delete-node/
>>>>
>>>
>>> I don't mind the suggestion Nishanth if there is a reason behind it.
>>> Could you tell why we should not be using /delete-node/?
>>>
>>
>> Maintenance, readability and sustenance are the reasons. This is a
>> optimized die. It will end up having it's own changes in property
>> and integration details. While reuse is necessary, modifying the
>> properties with overrides and /delete-nodes/ creates maintenance
>> challenges down the road. We already went down this road with am62p
>> reuse with j722s, and eventually determined split and reuse is the
>> best option. See [1] for additional guidance.
>>
>>
>> [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/dts-coding-style.rst#n189
>
> Thank you for giving some reasoning, would do the needful!
>

This refactor will require some interesting naming for the
common SoC files. Based on your name for the EVM, I'm guessing
you will go with

k3-j784s4-common.dtsi

included from the real k3-j784s4.dtsi and the new k3-j742s2.dtsi?

Too bad the Jacinto SoC names don't use a hierarchical naming. :(

J7<family><part><spin><etc>..

Andrew

> Regards,
> Manorit
>
>>
>> --
>> Regards,
>> Nishanth Menon
>> Key (0xDDB5849D1736249D) / Fingerprint: F8A2 8693 54EB 8232 17A3 1A34 DDB5 849D 1736 249D
>