Re: [PATCH v2 19/19] ARM64: dts: r8a77965: Add EtherAVB device node

From: Sergei Shtylyov
Date: Thu Feb 22 2018 - 14:08:57 EST


Hello!

On 02/22/2018 06:54 PM, Simon Horman wrote:

>>> ...
>>>
>>>>>>>>>> + clocks = <&cpg CPG_MOD 812>;
>>>>>>>>>> + power-domains = <&sysc 32>;
>>>>>>>>>> + resets = <&cpg 812>;
>>>>>>>>>> + phy-mode = "rgmii-txid";
>>>>>>>>>
>>>>>>>>> Why not just "rgmii"? TX delay is a board specific detail, no?
>>>>>>>>>
>>>>>>>> I admit I took this one straight from r8a7796 dtsi.
>>>>>>>> Would you like to me resend and change this?
>>>>>>>
>>>>>>> Yes, unless Simon would fix it while merging...
>>>>>>
>>>>>> Can I confirm the desired change is s/rgmii-txid/rgmii/ ?
>>>>>
>>>>> Yes.
>>>>
>>>> Apparently that means that this prop should be overridden in the board file
>>>> (which may not be an easy task given the board is Salvator-XS again).
>>>>
>>>> [...]
>>>
>>> Can we override it in r8a77965-salvator-x.dts or r8a77965-salvator-xs.dts?
>>
>> In salvator-common.dtsi most probably -- it has the PHY data for Ether AVB.
>>
>>> I feel that I'm missing an important point here.
>>
>> Well, r8a779{5|6}.dtsi also have phy-mode = "rgmii-txid" (which was
>> unjustified in my current understanding). Thus such board override
>> wouldn't hurt them. But we lack a patch modifying salvator-common.dtsi
>> in htis series, so I'm now thinking a respin of this series is needed
>> anyway... sorry for being unclear. :-)
>
> While I've applied other patches in this series I have
> not applied this one - mainly to allow this discussion to conclude.
>
> Is an appropriate solution to do the following?
>
> 1) Atomically update
> a) r8a779{5|6}.dtsi to use "rgmii" and
> b) salvator-common.dtsi to use "rgmii-txid"
> 2) Update this patch to use "rgmii"

Yeah, I was thinking about doing exactly this...

> Sorry if I'm still missing the point.

I was referring to what the 2nd paragraph of [1] said about the internal delays
(perhaps I just misunderstood it)...

[1] https://en.wikipedia.org/wiki/Media-independent_interface#Reduced_gigabit_media-independent_interface

MBR, Sergei