Re: [Qemu-devel] [RFC][PATCH 000/111] QEMU m68k core additions

[Natalia Portillo]

El 19/08/2011, a las 09:55, François Revol escribió:

> Le 19/08/2011 04:14, Natalia Portillo a écrit :
>> Hi,
>> 
> 
> [...]
> (no need to quote the full thread!)
> 
>>>> 
>>>> He worked on emulating an abandoned, strange, difficult to get, and 
>>>> undocumented hardware, using your 111 patches, and finished it before the 
>>>> wholy more experienced MESS team.
>>> 
>>> The next-cube emulation is really working ?
>> 
>> Yes, it is, absolutely.
> 
> Cool I need to add this target to my Haiku port... where are the docs for the 
> boot process ?

NetBSD sources :D

> 
>>>>>> Why are you planning to port a hack instead of making a full machine
>>>>>> emulation?
>>>>> 
>>>>> Because I'm lazy and dumb: the work is already done, I like cut'n'paste.
>>>> 
>>>> Yeah, you said it!
>>>> The work is already done, we have all the hardware emulation that Basilisk 
>>>> substitutes for hacks.
>>> 
>>> I'm not sure of that... no MMU emulation, no Nubus, no ethernet card, no
>>> video card, no SWIM, no SCSI, ... useless with a patched ROM.
>> 
>> Macs do not have videocards :p, only the Mac II and we're not forced to 
>> emulate that one.
>> SWIM is a piece of cake that can be even implemented without ICs, just some 
>> logical arrays.
>> NuBus is not required for almost anything, only the video card uses it, and 
>> it's present only on the Mac II, a stub will suffice to make Toolbox be 
>> happy.
>> Most m68k didn't include a network card, third party ones are stock chips 
>> (probably almost all are NE2000, 3COM and PCNET), and Apple integrated ones 
>> are also stock, easy to do :p
> 
> NIC isn't really necessary at first, those things don't netboot anyway, do 
> they ?

AFAIK, none of them did until PowerPC, and that was OpenFirmware.

>> The MMU is your part I won't discuss on it.
> 
> There is 040 mmu support in ARAnyM (Atari Running on Any Machine), enough to 
> run Linux, that has been backported to UAE (ARAnyM is based on the UAE core), 
> that should give some hints:
> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=201442
> http://www.amigaemulator.org/patches
> http://www.amigaemulator.org/bin/patches/mmu/uae-0.8.20.2-mmu.diff.gz
> (though I fixed a bug in handling TTR1 in ARAnyM)
> 
> It's why I chose to go Falcon first and use ARAnyM for the 68k Haiku port.
> 
> The 030 or 68551 ones are much more complex though (the 040 one has a fixed 
> table layout, others have fully configurable table size for all the 4 
> levels). The 060 one is just the 040 with some cache restrictions.
> 
>> I know it's not perfect, but right now, it's better than nothing.
>> There is no 68k cpu emulation complete afaik, I discussed with Ray 
>> Arachelian a lot on that when he was working on LisaEm.
>> However emulators are live, Aranym, UAE, LisaEm, BasiliskII.
>> 
>> qemu-m68k is quite complete to go live (when it does not break mcoldfire) 
>> right now.
>> Bugs are easy to be corrected by more people when they are in main than in a 
>> developer's own clone.
>> 
>> Leave your little kid go wild, it's old and big enough :p
> 
> Release early, release often :p

+1

> François.