Is Psp Emulation Really Feasible?

[filiphhh]

Also; I believe that is the emulator that was being referred to. The PSP is normally incapable of booting from ISOs, so it is likely that some form of emulation would be required to get around the expected drive configuration of the PSP.

No. You just have to patch some functions, I believe.

It was really just a typo, I believe Squidge was referring to one of the PSP emulators for PC.

It's basicly an image loader, and patched functions to "mount" the contents of the image as contents of the umd.

 

[Adventus]

QUOTE
PSP claims to be able to handle far more triangles than SGX 530 to begin with
http://forums.ps2dev.org/viewtopic.php?t=4703&highlight=

These benchmarks were unable to get above ~13M vertices/sec optimised thoughput. From memory, the max i've read in game is ~7M/sec. According to dmdm, we should be able to sustain a realworld ~10M vertices/sec. Again not sure how far i should read into these numbers, considering the obvious architectural differences. You seem to be very worried about the SGX....

Anyway fantastic project, I would love to be able to do this stuff, even more so now that it appears we could get decent speed on a few games.

 

[Exophase]

QUOTE
PSP claims to be able to handle far more triangles than SGX 530 to begin with
http://forums.ps2dev.org/viewtopic.php?t=4703&highlight=

These benchmarks were unable to get above ~13M vertices/sec optimised thoughput. From memory, the max i've read in game is ~7M/sec. According to dmdm, we should be able to sustain a realworld ~10M vertices/sec. Again not sure how far i should read into these numbers, considering the obvious architectural differences. You seem to be very worried about the SGX....

Anyway fantastic project, I would love to be able to do this stuff, even more so now that it appears we could get decent speed on a few games.


I wonder how the maximum number of polygons used in a game was determined. You would think that games could get the same 13M/sec vertices as in this benchmark (games running at 333MHz anyway, which would just be more recent ones) - although the benchmark was done w/o lighting I imagine the lighting could be done on the VFPU if it did bring performance down. If not that then it makes you wonder what the VFPU is even being used for.

It begs the consideration in general, how and why typical games actually stress the VFPU (if they do).

 

[hlidegp2x]

I wonder how the maximum number of polygons used in a game was determined. You would think that games could get the same 13M/sec vertices as in this benchmark (games running at 333MHz anyway, which would just be more recent ones) - although the benchmark was done w/o lighting I imagine the lighting could be done on the VFPU if it did bring performance down. If not that then it makes you wonder what the VFPU is even being used for.

It begs the consideration in general, how and why typical games actually stress the VFPU (if they do).

When MrMr[iCE] was around, both were working on VFPU for his vfpu libmath and his demo. Using vfpu to compute vectors and lights through VFPU allows us largely to boost the number of triangles to draw in his demo. He was so excited.

 

[hlidegp2x]

The only fear is that the games heavily use the Allegrex's FPU in a way such that it does not map well to NEON. And you'd want to throw NEON at VFPU emulation as much as possible, so would not want to tie up resources in register caching FPU for it, etc.

FPU has a major problem CPU hasn't : latencies. For instance, a simple ADD.S has a 4-cycle latency, so it means you can use the result only after running the next 3 instructions. So I hope the game doesn't abuse them. Don't think we can easily cache NEON registers for VFPU. The fact that there are potential prefixes (swizzle, neg, abs, constant insertion, etc.) for a VFPU operation, that a vector register can be accessed as a column or a row from a matrix register and so on, let me think mapping VFPU instructions on NEON instructions is a big hassle.

Although there are only two types of RAM, there are more than one region for each because of cached vs. uncached. However, because none of these read/writes have any side effects this is a perfect opportunity to use mmap to emulate it directly. You just need to make sure that the address space the emulator needs is placed somewhere where user mode on PSP cannot access, and this can most likely be guaranteed with a proper linker script.

True, I also thought this possibility, without the certainty it would be doable in Linux.

Although there are only two types of With both memory and I/O out of the way you're free to make a very efficient recompiler. Having direct memory accesses means that you can do complex conversions say from series of loads/stores to ldm/stm. I would love to see constant, move, and shift propagation employed to better take advantage of the strengths of the ARM architecture over MIPS32 (and help fight some of the disadvantages). This would work well for addressing especially, IE converting "shl r1, r3, 2; add r2, r2, r1; ld r1, (r2)" into "ldr r1, [r2, r3, lsl #2]" at least. Also some kind of efficient global register allocation.. it could all get very complex, be sure to write a dissertation on it when you're done. But you've already been doing MIPS->ARM recompilation anyway.

and
CODE

shl $s1, $s2, 2
addiu $s4, $s4, 1
addu $s3, $s3, $s1
addiu $s5, $s5, -1
lw $s1, 4($s3)
lw $s2, 0($s3)


?
besides, you'll need to be sure that r2 is not persistent (imagine this being used in a loop). In fact you must turn a basic block into an IR tree then compile it into a native binary. Yeah a dissertation would be necessary.

 

[Tozarian]

Psp emulation would be amazing! It is definitely not impossible.

 

[flammablepiss]

It would be amazing in technical terms.
But whats the bloody point ? Just go buy a psp if you want to play psp games, you gonad !

 

[Mistabeen]

the point would be not having to carry along both your pandora and PSP ^^
following your way of reasoning, you could drop all portable system emulators (GBA, gameboy, gamegear,) hell you could even drop PSX seeing as you can run those on the PSP at full speed

 

[WizardStan]

the point would be not having to carry along both your pandora and PSP ^^

My reasoning there goes: if you're going somewhere short, you don't need two gaming systems anyway. One that does a lot of stuff, even if it doesn't do everything, should be sufficient.
If you're going on a longer trip where having everything would be good, you're probably packing a lot anyway, so what's another little game system?
If you're going out shopping with the missus and really, really need to swap between SNES, Gameboy, PSP, and MAME games, then I suggest you fill up your "medication that reduces symptoms of ADD" prescription.

edit: apparently there's been some problems with spam in the past?

 

[emil10001]

I don't think that being stuck in a mall for hours on end and getting bored with one or two systems warrants ADD medication. OTOH, I usually just bring a book. =)

 

[God Ginrai]

the point would be not having to carry along both your pandora and PSP ^^

My reasoning there goes: if you're going somewhere short, you don't need two gaming systems anyway. One that does a lot of stuff, even if it doesn't do everything, should be sufficient.
If you're going on a longer trip where having everything would be good, you're probably packing a lot anyway, so what's another little game system?
If you're going out shopping with the missus and really, really need to swap between SNES, Gameboy, PSP, and MAME games, then I suggest you fill up your "medication that reduces symptoms of ADD" prescription.

edit: apparently there's been some problems with spam in the past?


How about this reasoning then: Not everyone has the money to buy BOTH the Pandora and the PSP.

And this reasoning: The Pandora will have a better Dpad than the PSP

And even this reasoning: The Pandora has a better screen than the PSP (which shouldn't have those damn ghosting problems either)

-God Ginrai

 

[Mistabeen]

you forgot bragging rights: oh... you got a psp there, nice.... My Pandora can f*ing EMULATE your psp, KNEEL BEFORE ME NOW AND DO MY BIDDING (or something among those lines, perhaps a bit less powerhungry )

 

[MagicPants]

the point would be not having to carry along both your pandora and PSP ^^
following your way of reasoning, you could drop all portable system emulators (GBA, gameboy, gamegear,) hell you could even drop PSX seeing as you can run those on the PSP at full speed

This is my main gripe with the PSP, Sony wants me to carry around a whole bag of cr*p with it, UMD games, UMD movies, extra batteries, earphones, etc... The thing that appeals to me about the Pandora is everything goes into the SD cards, and I don't have to carry a bag of cr@p with me.

 

[God Ginrai]

you forgot bragging rights: oh... you got a psp there, nice.... My Pandora can f*ing EMULATE your psp, KNEEL BEFORE ME NOW AND DO MY BIDDING (or something among those lines, perhaps a bit less powerhungry )

No I didn't. I already mentioned it 2 pages ago. See?:

[...]
I would want PSP emulation to brag to my PSP-toting friends, [...]

-God Ginrai

 

[WizardStan]

How about this reasoning then: Not everyone has the money to buy BOTH the Pandora and the PSP.

If so, you probably don't have the funds with which to purchase the UMDs that you would be obligated to buy in order to make ISO playing even remotely legal.
*cough cough* h34r:

QUOTE

And this reasoning: The Pandora will have a better Dpad than the PSP


That's debatable. I've ne'er had problems with my PSP pads.

QUOTE

And even this reasoning: The Pandora has a better screen than the PSP (which shouldn't have those damn ghosting problems either)


Ok, you win this round.

 

[n8archer_XI]

The PSP is cheaper than the Pandora, so why?

 

[atomicthumbs]

It would be amazing in technical terms.
But whats the bloody point ? Just go buy a psp if you want to play psp games, you gonad !

portable integration

(you win the award for creative insults)

 

[Tinnus]

How about this reasoning then: Not everyone has the money to buy BOTH the Pandora and the PSP.

If so, you probably don't have the funds with which to purchase the UMDs that you would be obligated to buy in order to make ISO playing even remotely legal.
*cough cough* h34r:
Not to mention you actually need a PSP to dump the image files.

 

[God Ginrai]

How about this reasoning then: Not everyone has the money to buy BOTH the Pandora and the PSP.

If so, you probably don't have the funds with which to purchase the UMDs that you would be obligated to buy in order to make ISO playing even remotely legal.
*cough cough* h34r:


Do you plan on emulating anything? Because if you do, I really doubt you'd adhere to those standards yourself, and therefore have no right to make that remark.

QUOTE

And this reasoning: The Pandora will have a better Dpad than the PSP

That's debatable. I've ne'er had problems with my PSP pads.


Sony is on record for always having one of the Shittiest Dpads money can buy. Only the PSPhreaks may argue otherwise.

-God Ginrai

 

[WizardStan]

How about this reasoning then: Not everyone has the money to buy BOTH the Pandora and the PSP.

If so, you probably don't have the funds with which to purchase the UMDs that you would be obligated to buy in order to make ISO playing even remotely legal.
*cough cough* h34r:


Do you plan on emulating anything? Because if you do, I really doubt you'd adhere to those standards yourself, and therefore have no right to make that remark.

Dude. Sarcasm. Heavy sarcasm. NINJA heavy sarcasm.
And of course all emulated games I will play will be personally owned and ripped, because to suggest otherwise would be quite illegal, and I would never do anything illegal, as I'm sure no one else here would consider doing either.