[LEDE-DEV] LEDE TODO: Convert ar71xx to devicetree

[Antony Pavlov]

On Tue, 10 May 2016 12:54:58 +0200
John Crispin <john at phrozen.org> wrote:


> On 10/05/2016 11:39, Antony Pavlov wrote:
> > Hi All!
> > 
> > I have just seen https://www.lede-project.org/todo.html
> > 
> > There is the "Convert ar71xx to devicetree" entry.
> > 
> > I'm working on this topic. You can see my patchseries
> > in the mips-linux mailing list:
> > 
> >   https://www.linux-mips.org/archives/linux-mips/2016-03/msg00256.html).
> > 
> > The patchseries is accepted by Ralf.
> > 
> > Please describe LEDE community plans on this topic.
> > 
> > LEDE TODO list contains the "Bump all kernels to v4.4" entry.
> > Are you planning add ar71xx devicetree support for linux-4.4
> > inside LEDE project?
> > 
> > I suppose I have to add some ar71xx kernel LEDE developers
> > to Cc in my future ar71xx patches for linux-mips.
> > Could you please recommend me somebody?
> > 
> 
> Hi Antony,
> 
> i have been keeping an eye on your upstream activity. thanks for the effort.
> 
> making use of the dts support in the tree consists of 2 parts
> 
> 1) backport any changes you sent upstream to our tree or simply build a
> staging tree based on 4.6/7
> 
> 2) convert the large number of mach-* files we currently have into dts files
> 
> when we converted ralink to dts, we built a framework to run the mac
> files init code on a x86 machine in batches. this framework then
> remembered what the mach files registered as devices and quirks and
> converted this into dts syntax. this worked for 80% of files, but a few
> quirks required us to extend some of_ callbacks in various drivers.

Hi John!

Is this ralink dts converting framework still available?
How can I get it?

> in the case of ar71xx i would suggest that we o a migration path where
> we start to convert a few boards at a time.
> 
> as for adding people into Cc: i think everyone is on the linux-mips
> mailing list already. this whole idea was spawned by the patches you
> have been submitting.
> 
> my question to you would be, how big is the delta between v4.4 and 4.6/7
> in regard to ath79 dts support patches ?

I have just finished work on rebasing an out-of-tree MIPS SoC (unrelated to Qualcom/Athros)
linux support code from v4.4 to v4.6-rc7. I suppose very few problems
with downgrading ar71xx devicetree code from v4.6 to v4.4.

The problem with ar71xx is that only very basic functionality is covered by devicetree.
The key LEDE ar71xx interconnect interfaces (wifi, ethernet, ethernet switch)
are not currently covered by devicetree.

-- 
Best regards,
  Antony Pavlov