Re: [Vice-emu-mail] cartridge subsystem mmu stuff

[Kajtár Z. <so...@c6...>]

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>>> this stuff should be reverted NOW and COMPLETELY.
>> 
>> This is a bit strong. I'm not in the mood to go into the flame war 
>> direction. Give details where it's wrong and if I see it's not a simple
>> fix I'll revert it myself right away.
> 
> sorry for my outburst - i had a stressfull day and blablainsertlameexcuse
> =P

I'm sure it happens to everyone once in a while ;)

> the reality is that i didnt (and still dont) really have the time to test
>  everything, and i feel these changes at least have the potential to
> break things and/or introduce bad hackery into the cartsystem.

Understandable, usually I'm also not happy at first when I see someone
messed with code I'm more familiar with ;) Therefore I tried to minimize the
chance of breaking things and use a familiar design.

> however, it would be nice if you would comment (in one of the main files
> of the cartsystem) how to migrate a cartridge to make use of your
> changes, and how to deal with things like the "ultimax mode hack"
> described in the comments.

I've added comments above cartridge_mmu_translate how things work, and not
too long ago added hooks to more cartridges which can be used as examples.

The ultimax hack as far as I understand is switching permanently to ultimax
mode to be able to supervise access to part of the address space for special
mappings while being mostly transparent. Usually it's implemented in
hardware by manipulating the game line in real-time depending on the address
bus content, at least on the few cartridges I've looked at.

The easiest is to use the current fallback, that is to not cache anything
and always go through hooks. But I think it's possible to speed it up as
there are ROMs and transparent areas which could be translated. I'll have a
look if I can find a cartridge image for testing and implement the
translation hook for it.

- -- 
						    -soci-
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