[LEDE-DEV] Convert ar71xx to devicetree

[John Crispin]

On 08/12/2016 18:10, Felix Fietkau wrote:
> On 2016-12-08 18:08, John Crispin wrote:
>>
>>
>> On 08/12/2016 18:06, Felix Fietkau wrote:
>>> On 2016-12-08 17:31, John Crispin wrote:
>>>> Hi,
>>>>
>>>> i was planning to start working on this in early 2017. i was hoping that
>>>> rather than converting ar71xx to DT we simply create a new target called
>>>> ath79 and start moving board support over from the legacy to the new
>>>> target. this would allow us to make the ath79 target much cleaner than
>>>> having to worry about legacy cruft.
>>>>
>>>> converting all the mach files to dts files is also a bit tricky. back in
>>>> the day when i converted ramips, i simply create a host lib that
>>>> provided all the platform_*() callbacks used by the mach files. however
>>>> rather than register anything the code simply generated the matching dts
>>>> files. this was really ugly, run once and throw away code.
>>>>
>>>> can you share the patches you have already created ? i think we could
>>>> start working on this now and once the new ath79 target starts to be
>>>> usable we simply refuse to merge patches to ar71xx and only accept ones
>>>> for ath79
>>> I think making this a separate target will make the transition period a
>>> lot more confusing for users. I think it should not be too hard to
>>> support both DT and non-DT devices with the same kernel.
>>>
>>> I fully agree with refusing to accept non-DT device support once a few
>>> devices work with DT.
>>>
>>> - Felix
>>>
>>
>> how would that be confusing ? i would argue the exact opposite
> Because suddenly there are two targets and you have to look up which
> device is supported by which target.
> 
> - Felix
> 

its a tradeoff we need to consider

1) chance to start a new clean target without legacy cruft
2) making it easy to find the snapshot

i would value 1) higher than 2)

	John