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From:   Arnd Bergmann <arnd@kernel.org>
Date:   Sun, 10 Jan 2021 20:20:36 +0100
Message-ID: <CAK8P3a1ggCWBEVP6qYS_p1bHdG1cbHvrN7iR8SfkhWrZ=jDzeQ@mail.gmail.com>
Subject: Re: Old platforms: bring out your dead
To:     Fabian Vogt <fabian@ritter-vogt.de>
Cc:     Daniel Tang <dt.tangr@gmail.com>, Baruch Siach <baruch@tkos.co.il>,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        Neil Armstrong <narmstrong@baylibre.com>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Linus Walleij <linus.walleij@linaro.org>,
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On Sun, Jan 10, 2021 at 7:12 PM Fabian Vogt <fabian@ritter-vogt.de> wrote:
> Am Samstag, 9. Januar 2021, 23:20:48 CET schrieb Arnd Bergmann:
> > On Sat, Jan 9, 2021 at 1:06 AM Daniel Tang <dt.tangr@gmail.com> wrote:
> > >
> > > Hi Arnd,
> > >
> > > On 9 Jan 2021, at 9:55 am, Arnd Bergmann <arnd@kernel.org> wrote:
> > >
> > > * nspire -- added in 2013, no notable changes after 2015
>
> Most of the platform is just the DT sources and some small drivers around it,
> so it's actually fairly low maintenance. So far the migration away from
> panel-simple in 2019
> (https://lore.kernel.org/linux-arm-kernel/20190805085847.25554-1-linus.walleij@linaro.org)
> was the biggest required change so far.

Sure, there is no problem in keeping it around as long as it is used.
There were a couple of platforms that had not seen a lot of changes
in the past five years but that are still in active use, I just used it as
an indication that I should ask about the status. A lot of the other
platforms that list only ever had an incomplete port and were
abandoned before they were fully supported in upstream kernels.

> > Would either of you already have a guess for how long it makes
> > sense to update kernels on it?
> >
> > I see that this is one of the more limited platforms with just 32MB
> > of RAM (64MB in case of CX), and kernels only get more bloated over
> > time, so I expect at some point you will be stuck with running old
> > software.
>
> The kernel overhead isn't actually that bad. I just built today's 2ff90100ace8
> and booted it with a busybox-based initrd. free -m reports:
> total used free shared buffers
>    58   12   46      0       0
>
> Relatively speaking, still mostly unused ;-) The stock OS actually uses more!
> With 32MiB, the situation is definitely worse, but still manageable. Should
> that change in the future, dropping just the Classic/CM variants would be a
> possible option, but that still seems far enough away.

Ok, makes sense.

> > Wikipedia tells me that new models came out recently. Are you
> > planning to add support for those as well?
>
> Yes, someone from the community actually managed to boot Linux on a CX II-T,
> and I'm hoping to get that upstreamed soon. Most of the hardware changes are
> supported by drivers already and so this is mainly just another device tree.

Nice!

       Arnd