Will PS2 Emulation on PS3 be PS2+?

[Fafalada]

Will the Cell SPU architecture be condusive to effecient emulation? I'd have thought not and software PS2 emulation would be handled entirely by PE.

Off hand, I think it depends on how well EE DMA can be mapped to Cell DMA (it's likely the latter is more capable, but we don't really know yet for sure).
If such a mapping is possible, PE could stick to R5900&R3000 emulation + translating the DMA chains to native DMA, passing them off to SPUs which would then emulate the "other" units in the system (VUs, IPU etc.).

 

[Npl]

EE could be used as IO-Processor (including Sound-DSP) similar to the PS1-CPU in the PS2.

You really do wish evil on the poor sound software engineers in nextgen games don't you...

Nay, I merely implied that the EE-Part could be used, I dint meant it really has to be a 1:1 Chip. Could be clocked faster in PS3-Mode and could have additional Stuff too. (Ive literally no experience (nor interest) in Soundprogramming , but I guess the SPU`s would do the heavy DSP-effects and then pass them to a simple hardware-mixer... )

For the IOP-Part:
From what Ive seen, it`s setup as some kind of RPC-Service and the loaded Modules are all from a set of Libraries from Sony. Would it be possible to simply replace the .irx Libraries with corresponding PS3-native( ie running on a PE) Versions during runtime? As long as the Data being sent around is the same it shouldnt matter what kind of Processor is "doing the talk".
I think lowlevel emulation of the IOP wont be necessary for PS2-Games

 

[Fafalada]

I guess the SPU`s would do the heavy DSP-effects and then pass them to a simple hardware-mixer...

Actually I suppose if EE had full access to XDR memory I guess it wouldn't be that bad, since you could always use SPUs to assist when needed. So for most things people could just stick to using R59k&VU0 in macro mode, which would be quite easy.
I'm more worried they'd cook up some intricate solution with extra sound memory attached ONLY to EE or something silly like that.

As for IOP - unfortunately it's not that simple, the thing was always open to write your own code for, and it runs custom modules in many games.

 

[Megadrive1988]

If you're expecting software emulation, then you should expect > 48 GB/s bandwidth somewhere in the PS3 because the GS eDRAM is ~ 48 GB/s.

Therefore, either eDRAM on the GPU or XDR RAM > 48 GB/s!

good point!

 

[j^aws]

If you're expecting software emulation, then you should expect > 48 GB/s bandwidth somewhere in the PS3 because the GS eDRAM is ~ 48 GB/s.

Therefore, either eDRAM on the GPU or XDR RAM > 48 GB/s!

The question is: Would you rather have 4MB edram that wont EVER be used except in PS2-Mode... or just spent the same amount of transistors to place it on the GPU, usable for all games even if it wont have benefits in all cases.
...

Putting a GS with 4MB of eDRAM doesn't seem to efficient as a whole and rather redundant to PS3's design goals, IMO.

I'd rather a see a partial HW emulation solution (i.e. EE core + GS in SW) or fully SW emulation solution. In this way you get the benefits/ flexibility of enhancing PS2 games and you'd also be setting a certain 'minimum' spec for the PS3 aswell. I.e. the dilema would then be should we have eDRAM and/or XDR with > 48 GB/s! 8)

Considering that some believe there's a good chance of NO eDRAM for the GPU and XDR badwidth ~ 25 GB/s, this would be a good thing (TM)! 8)

 

[corysama]

EE could be used as IO-Processor (including Sound-DSP) similar to the PS1-CPU in the PS2.

You really do wish evil on the poor sound software engineers in nextgen games don't you...

For the IOP-Part:
From what Ive seen, it`s setup as some kind of RPC-Service and the loaded Modules are all from a set of Libraries from Sony. Would it be possible to simply replace the .irx Libraries with corresponding PS3-native( ie running on a PE) Versions during runtime? As long as the Data being sent around is the same it shouldnt matter what kind of Processor is "doing the talk".
I think lowlevel emulation of the IOP wont be necessary for PS2-Games

I wouldn't be suprised if they included the SPU for backwards compatibility and then recomended that no one use it for anything but direct output of SPE-mixed PCM. Alternatively, the SPU would probably be one of the easier processors of the PS2 to emulate in software.

As for the IOP:
It is possible for games to create their own IOP modules. Also, the modules provided by Sony have changed slowly over the years. So doing a high-level emulation of the IOP RPC would not be sufficient. By now the PSOne processor should be so small and cheap that Sony shouldn't mind churning them out for yet another ten years.