Re: [hatari-devel] UAE 68030 MMU + prefetch + instruction and data cache emulation

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 28/07/2017 à 15:25, Nicolas Pomarède a écrit :

> MMU not enabled :
>
> - Cycle Exact    68030 CE + caches (internal mode=4  op_smalltbl_24_ff)
> - Prefetch    68030 prefetch, no cache (internal mode=3  op_smalltbl_22_ff)
> - none        68030 basic, no cache (internal mode=0  op_smalltbl_2_ff)
>
>
> MMU enabled :
>
> - Cycle Exact    68030 MMU + prefetch + cache (internal mode=6 
> op_smalltbl_34_ff)
> - Prefetch    68030 MMU + prefetch + cache (internal mode=6  
> op_smalltbl_34_ff)
> - none        68030 MMU, no cache (internal mode=5  op_smalltbl_32_ff)
>
>
> NOTE :
>
>   - there's no "cycle exact" mode for now in 68030 MMU, it's the same 
> emulation as "prefetch". For "cycle exact" 68030 (instructions tail/head 
> and more accurate cycles) don't use MMU mode.
>
>   - even in "cycle exact" mode without MMU, cycles are not always 
> correct yet, this is still work in progress.

As a followup to this description, a specific opcodes table was added 
for 68030 + MMU in cycle exact mode.

So now, it uses internal mode=7 and table op_smalltbl_35_ff, which 
should basically gives the same cycles results as already available for 
"68030 without MMU + CE" (ie internal mode=4  op_smalltbl_24_ff), but 
with additional MMU support.

Eventually, this mode will be the prefered one to emulate a Falcon (when 
cycle accuracy will be complete for all cases)

Nicolas