Re: M68k backend has landed in LLVM - NetBSD support

[mlelstv%serpens.de@localhost (Michael van Elst)]

john%ziaspace.com@localhost (John Klos) writes:

>Now's the time... I have another Amiga with 336 megabytes - it could have=
>=20
>as much as 912 megs - and a Macintosh Quadra with 520 megabytes, and=20
>neither can use the full amount yet.

This is the current limit:

[   1.0000000] total memory = 2048 MB
[   1.0000000] avail memory = 2019 MB
[   1.0000000] Amiga 4000 (m68040 CPU/MMU/FPU)
[   1.0000000] memory segment 0 at 40000000 size 80000000
[   1.0000000] memory segment 1 at 00000000 size 00200000

but:

memory        (-m kbytes     )       491520

Obviously that's virtual hardware.

>I'd love to find any books, documentation, whatever, about MMU setup on=20
>m68k. I'm learning what I can from NetBSD's Alpha code - it ain't easy!

https://www.nxp.com/docs/en/reference-manual/MC68030UM-P1.pdf
https://www.nxp.com/docs/en/reference-manual/MC68040UM.pdf
https://www.nxp.com/docs/en/data-sheet/MC68060UM.pdf

68040 and 68060 use a simpler MMU.