Old platforms: bring out your dead

[Geert Uytterhoeven]

Hi Adrian,

On Mon, Jan 11, 2021 at 10:26 AM John Paul Adrian Glaubitz
<glaubitz at physik.fu-berlin.de> wrote:
> On 1/11/21 10:20 AM, Geert Uytterhoeven wrote:
> >> Sounds interesting. Do these SoCs come with an MMU? And do they use the
> >> ColdFire instruction set or do they run plain 68k code?
> >
> > No MMU, plain m68k code.
> >
> > 68328 Soc = 68000 core + some peripherals,
> > 68360 SoC = CPU32 core (based on 68020 + some peripherals.
>
> OK, I guess that would be useful for the NoMMU Linux port.

Note that 68360 support was removed from the kernel in 2016, as
Arnd said.

> > Anyone working on integrating m68k (and SPARC and MIPS?) softcores in
> > LiteX? ;-)
>
> I'm personally waiting for the Vampire to gain support for the real 68851
> as the hardware in general looks very attractive [1].

The 68851 is way too complex for what's needed (who needs support for
256 byte pages (https://lwn.net/Articles/839746/)?).
They'd be better off implementing something simpler, like 68040 MMU
support, or perhaps even a software-controlled TLB like most RISC
architectures (incl. ColdFire?).  The latter would require more changes
to Linux, though.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds