Re: [PATCH 0/4] Atari kernel-in-FastRAM patches, take three

Geert Uytterhoeven
2014-04-01T07:50:25Z

Hi Michael,

On Tue, Apr 1, 2014 at 9:45 AM, schmitz
<schmitz@biophys.uni-duesseldorf.de> wrote:
>>>>> do we know the size of the first memory chunk early enough in head.S?
>>>>> Maybe it's time to increase INIT_MAPPED_SIZE at least in cases where
>>>>> we know that there's more than 4 MB in the first memchunk ...
>>>>
>>>> How do you know? You would have to reimplement the check paging_init
>>>> does.
>>>
>>> I see - as a heuristic, we can probably assume that the first memchunk is
>>> the relevant one, and especially in the case of FastRAM, also the larger
>>> one.
>>> Does this hold for Amiga/Mac/VME as well?
>>
>> People want to run the kernel in the fastest memory chunk, which is
>> typically
>> also the largest (slow Amiga mainboard memory may be 2 - 16 MiB for
>> Linux-capable machines, accelerator memory may be larger).
>
> And the chunk the kernel runs from would always be the first chunk listed in
> bootinfo, since that's the one mapped at virtual address zero?

The kernel always runs in the first chunk.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@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