Emulator

With full MMU, BAT and PPC Emulation set to interpreter, the first screen fades to black.

After that, we get the attached message via OSREPORT.

Woo mmu and/or interpreter issue!!! Where is booootooooooo.

Do you get that osreport when not using mmu ?

Skid is the MMU guy, CC him first. :p

He isn't, booto secretly is!

But sshhh, don't tell anyone!

MMU Speed hack makes it just freeze at the opening screen. No MMU => crash.

This game uses real virtual memory, that is, it maps a portion of physical memory to varying addresses in the 0x7fxxxxxx range(thus needing a fully emulated MMU). The game uncompresses data on demand in some fault-handler for the "virtual" addresses. It is this handler, that gives the osreport, after it worked correctly for a while.

I suspect the problem is in the TLB cache. The number of entries in the cache and how they are being flushed is not accurate to the real hardware.

Actually this game is extra clever, it creates a virtual range of 32MB and segments it for both code and data:

--- GSYS VM init ---
Original arena: 0x800ac900 - 0x817fe7c0
Found compressed VM data at 80200000 (2152886 bytes)
Found boot user data at 80680000 (473728 bytes)
VM memory management table is at 0x800ad000
ARAM management at 0x800b3a80, effective address ARAM mapping at 0x800bbe80
33554432 bytes of virtual memory setup at 0x7e000000 using 4653056 bytes of physical memory at 0x000e0000
VM physical page priority evaluation active.
Adding 57344 bytes of physcial memory to VM system (PageTable gap)...
Decompressing VM data... (2152886 bytes -> 6307168 bytes)
Copying 4617568 bytes of text section data to 0x7f200000...
Copying 124480 bytes of data section data to 0x7f668000...
Copying 1564864 bytes of data section data to 0x7f687000...
Clearing VM BSS area at 0x7f806000 (428704)...
VM Data copy finished.
User VM heap reserved from 0x7e000000 to 0x7f200000
Truncated arena: 0x80550000 - 0x817fe6c0
--- GSYS VM init done ---

Exactly how it manages to map 32MB of VMEM to 16MB of ARAM I'm not sure. Maybe it just never uses more than ~9MB of the "User VM heap".

Accurate emulation of the TLB cache shouldn't be necessary, but what does need to be correct is updating the R and C bits of PTEs - the C bit is used to know if a page has been modified and needs to be written when paged out (this is common) and this game also seems to play with the R bit as part of an algorithm (see the reference to "page priority") to decide which pages to switch out (not so common).

Thanks, tueidj. I will work on the R and C bit emulation as that is also not accurate in the current MMU emulation.

Something else I just thought of that may or may not be relevant for this game (but definitely is for others e.g. Ultimate Spider Man): pages can be mapped as read-only, in which case any stores to those pages should set bit 4 in DSISR (protection violation) instead of bit 1 (page fault) when taking the DSI exception.

tueidj, why u no join the dolphin side O:)

Are you suggesting this worked in r4?

FOREVER AND EVER!!!

Thanks for the input, marcos. :p

Issue 6024 has been merged into this issue.

I was really excited to read these developer comments below the submitted issue report, but what isn't clear is if this game works or not. On the official dolphin game thread it says that the game is broken. Is that still true? Please, for the love of everything co-op, outsmart r2d2 and hack this thing. i will send a reward of 10 argentine pesos in the mail as soon as it's done ;)

joining the question above

Issue 6530 has been merged into this issue.

I´m a totally neofit player that use your amazing emulator.
Do you think that the game will work properly anytime?
Thanks for your efforts and your work.
Greetings from Spain.

Still broken as of 3.5, and even worse the fix (albeit less than ideal) recommended in the Wiki for Dolphin on the page for this game, (that worked supposedly back in version 3.0 of Dolphin, by using MMU, MMU Speed Hack, and Interpreter) doesn't work in 3.5 Dolphin.

PLEASE FIX THIS!

NTSC Versions fixed as of 4.0-3473 (https://dolphin-emu.org/download/dev/19fbefd9bd11536b797542f763a53d5aaeb27893/)