Re: [PATCH v2 0/5] Introduce IEP driver and packet timestamping support

From: Md Danish Anwar
Date: Wed Aug 09 2023 - 01:01:45 EST


On 08/08/23 6:15 pm, Conor Dooley wrote:
> On Tue, Aug 08, 2023 at 06:06:11PM +0530, Md Danish Anwar wrote:
>> On 08/08/23 5:52 pm, Roger Quadros wrote:
>>>
>>>
>>> On 08/08/2023 15:18, Md Danish Anwar wrote:
>>>> On 08/08/23 5:38 pm, Conor Dooley wrote:
>>>>> On Mon, Aug 07, 2023 at 04:30:43PM +0530, MD Danish Anwar wrote:
>>>>>> This series introduces Industrial Ethernet Peripheral (IEP) driver to
>>>>>> support timestamping of ethernet packets and thus support PTP and PPS
>>>>>> for PRU ICSSG ethernet ports.
>>>>>>
>>>>>> This series also adds 10M full duplex support for ICSSG ethernet driver.
>>>>>>
>>>>>> There are two IEP instances. IEP0 is used for packet timestamping while IEP1
>>>>>> is used for 10M full duplex support.
>>>>>>
>>>>>> This is v2 of the series [v1]. It addresses comments made on [v1].
>>>>>> This series is based on linux-next(#next-20230807).
>>>>>>
>>>>>> Changes from v1 to v2:
>>>>>> *) Addressed Simon's comment to fix reverse xmas tree declaration. Some APIs
>>>>>> in patch 3 and 4 were not following reverse xmas tree variable declaration.
>>>>>> Fixed it in this version.
>>>>>> *) Addressed Conor's comments and removed unsupported SoCs from compatible
>>>>>> comment in patch 1.
>>>>>
>>>>> I'm sorry I missed responding there before you sent v2, it was a bank
>>>>> holiday yesterday. I'm curious why you removed them, rather than just
>>>>> added them with a fallback to the ti,am654-icss-iep compatible, given
>>>>> your comment that "the same compatible currently works for all these
>>>>> 3 SoCs".
>>>>
>>>> I removed them as currently the driver is being upstreamed only for AM654x,
>>>> once I start up-streaming the ICSSG driver for AM64 and any other SoC. I will
>>>> add them here. If at that time we are still using same compatible, then I will
>>>> modify the comment otherwise add new compatible.
>>>>
>>>> As of now, I don't see the need of adding other SoCs in iep binding as IEP
>>>> driver up-streaming is only planned for AM654x as of now.
>>>
>>> But, is there any difference in IEP hardware/driver for the other SoCs?
>>> AFAIK the same IP is used on all SoCs.
>>>
>>> If there is no hardware/code change then we don't need to introduce a new compatible.
>>> The comment for all SoCs can already be there right from the start.
>>>
>>
>> There is no code change. The same compatible is used for other SoCs. Even if
>> the code is same I was thinking to keep the compatible as below now
>>
>> - ti,am654-icss-iep # for K3 AM65x SoCs
>>
>> and once other SoCs are introduced, I will just modify the comment,
>>
>> - ti,am654-icss-iep # for K3 AM65x, AM64x SoCs
>>
>> But we can also keep the all SoCs in comment right from start as well. I am
>> fine with both.
>
>> Conor / Roger, Please let me know which approach should I go with in next revision?
>
> IMO, "ti,am564-icss-iep" goes in the driver and the other SoCs get
> specific compatibles in the binding with "ti,am564-icss-iep" as a
> fallback.

Sure. Then as for now, "ti,am654-icss-iep" goes in the driver, I will keep the
dt binding compatible as below (as it was earlier in v1.)

- ti,am654-icss-iep # for K3 AM65x, J721E and AM64x SoCs

When new SoCs are introduced I can add specific bindings for them with
"ti,am654-icss-iep" being the fallback.

--
Thanks and Regards,
Danish.