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Re: [MiNT] 68030 MMU crash course?

"George (HOL, IMAP)" <ggn@hol.gr> writes:

>   Could someone from the list help? I don't request anything too fancy,
> just something like "to map memory range from x to y do this: ....".

The 68030 MMU works like any other MMU: the root descriptor points to a
descriptor table that is indexed by the top N1 bits of the virtual
address.  This entry points to the second level table that is indexed by
the next N2 bits.  This is repeated until as much bits are left to
represent the page size.  The last entry thus determined defines the
physical address of the containing page, adding in the remaining bits of
the virtual address gives the final physical address.

The page size and the number of bits that are consumed at each level is
determined by the mmu configuration register.


Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
PGP key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."