Specifically, 'Scooby-Doo! Mystery Mayhem', 'Scooby-Doo! Unmasked', 'Ed, Edd n Eddy: The Mis-Edventures', and the Wii version of 'Happy Feet'.
The JIT cache causes problems with emulated icache invalidation in these games, resulting in areas failing to load.
These games are erroneously zeroing buffers before they can be fully copied to ARAM by DMA. The responsible memset() calls are followed by a call to DVDRead() which issues dcbi instructions that effectively cancel the memset() on real hardware. Because Dolphin lacks dcache emulation, the effects of the memset() calls are observed, which causes missing audio.
In a comment on the original bug, phire noted that the issue can be corrected by simply nop'ing out the offending memset() calls. Because the games dynamically load different .rel executables based on the character and/or language, the addresses of these calls can vary.
To deal generally with the problem of code being dynamically loaded to fixed, known addresses, the patch engine is extended to support conditional patches which require a match against a known value. This sort of thing is already achievable with Action Replay/Gecko codes, but their use depends on enabling cheats globally in Dolphin, which is not a prerequisite shared by patches.
Patches are included for every region, character, and language combination. They are enabled by default.
The end result is an approximation of the games' behavior on real hardware without the associated complexity of proper dcache emulation.
https://bugs.dolphin-emu.org/issues/9840
This game can deadlock the CPU and GPU by setting FIFO breakpoints too infrequently, provided the CPU gets too far ahead, as can happen under Dolphin due to timing inaccuracies. The game never clears breakpoints, and it will skip setting them if the previous one has not been hit by the GPU. If the CPU gets far enough ahead it will reach the FIFO high water mark and trigger an overflow interrupt, causing the render thread to be suspended. The GPU will make forward progress until it hits the last set breakpoint. However, if the distance between that breakpoint and the FIFO write pointer is greater than the low water mark, then the GPU will never generate an underflow interrupt and the render thread will never be resumed. This patch forces the game to update the breakpoint unconditionally and has been tested on real hardware with no apparent ill effect.
This patch covers the US release (GLSE64), but there are three more (GLSD64, GLSF64, GLSP64) that will likely require similar patches.
This fixes the crash at Goblin Wall: https://bugs.dolphin-emu.org/issues/9915
A patch (for the US release only) that fixes the game's buffer overrun bug is included as an alternative with lower performance cost. It is disabled by default.
The first call to GXCopyDisp() corrupts game data, but on real hardware it isn't observed thanks to the data cache. Skipping the call works too, preventing a crash on boot.
This patch is enabled by default.
This enables patches for game-breaking problems by default.
My criterion for which patches to select was that the patch
has to make the game's behavior closer to how the game acts
on console. So workarounds for Dolphin not emulating caches
accurately are enabled by default, but not things like
Twilight Princess's minimap speedhack or patches for
disabling memory card checks in Pokémon games.
This game requires EFB turned off, otherwise every game will black screen, and it requires Safe Texture Cache to Safe, otherwise the cursor in game won't update, making it really hard to navigate the menu's
JMC47