Re: [PATCH 01/27] ARM: pxa: remove unused board files

[Dmitry Baryshkov]

пт, 6 янв. 2023 г. в 11:47, Arnd Bergmann <arnd@xxxxxxxx>:
>
> On Thu, Jan 5, 2023, at 23:45, Richard Purdie wrote:
> > On Thu, 2023-01-05 at 23:16 +0100, Arnd Bergmann wrote:
> >> On Thu, Jan 5, 2023, at 18:05, Richard Purdie wrote:
> >> > On Thu, 2023-01-05 at 17:50 +0200, Dmitry Baryshkov wrote:
> >>
> >> In the long run, I expect we will remove all the remaining
> >> legacy boardfiles and only keep the DT support. Ideally
> >> if someone is motivated to convert spitz to DT, supporting
> >> corgi the same way is also easy.
> >
> > Personally, I'm not that interested in tosa (or poodle/collie).

I think I was one of the last devs having interest in tosa. It worked
mostly fine except the offline charging.

> >
> > The other zaurus devices are interesting for me as I know the platform,
> > they have qemu emulation, there are set of devices which are similar
> > but also have differences and there were one of the original targets
> > for OpenEmbedded and Yocto Project. I did quite a bit of work to get
> > one kernel which could run on multiple devices, as best you could at
> > the time! I'd actually forgotten about the qemu emulation.
> >
> > There is a need for better automated testing around DT in OE/YP and
> > this is making me wonder about a few potential ideas.
>
> Ok
>
> > Is there any conversion to DT you can easily point at as an example of
> > the kinds of changes needed?
>
> Robert Jarzmik and Daniel Mack worked on the conversion of the
> PXA platform to DT. Daniel contributed the port for Raumfeld,
> which should be complete, while Robert worked on more driver
> conversions and mentioned[1] that he had converted additional
> boards in the past but did not merge it upstream. They
> can probably point you to whatever is missing. I would expect
> the generic PXA drivers (spi, mmc, nand, i2c, audio, fb, gpio,
> keypad) to  basically work work a correct DT description,
> while the machine specific drivers (scoop and pcmcia mainly)
> will need DT support in the driver.
>
> In addition, Linus Walleij and Marc Zyngier have both expressed
> interest in keeping sa1100 (h3600, collie, assabet, jornada720)
> alive, but those don't have any DT support yet and require
> much more work. Also note that while you can now build a kernel
> that includes support for all little-endian ARMv4T and ARMv5
> machines, StrongARM machine still require a separate kernel
> build.

I looked into converting collie to use DT several years ago. The major
problem was not in the StrongARM itself , but rather in the locomo
(platform-specific ASIC) and PCMCIA. Unfortunately I abandoned that
work ages ago. RMK didn't seem to be very interested, if I remember
correclty.

I suspect that the platforms might need to be rebootstrapped from the
ground up. This sounds like a fun project for the next Connect demo :D

BTW: collie is also supported by the qemu (in fact at some point I
mostly used qemu for debugging collie). I don't think that the LCD
emulation works, but the rest should be mostly good.

>
>      Arnd
>
> [1] https://lore.kernel.org/all/803778517.2279639.1667493436959.JavaMail.open-xchange@xxxxxxxxxxxxxxxxxxxxx.intraorange/

-- 
With best wishes
Dmitry