diff --git a/Data/Sys/GameSettings/RX4E4Z.ini b/Data/Sys/GameSettings/RX4E4Z.ini new file mode 100644 index 0000000000..007e8d255b --- /dev/null +++ b/Data/Sys/GameSettings/RX4E4Z.ini @@ -0,0 +1,26 @@ +# Casper's Scare School: Spooky Sports Day (RX4E4Z) + +[OnFrame] +# Work around a dcache issue by preventing the game from doing something pointless. +# +# The game's DVD read function writes 0x87654321 to the entire read buffer and 0x12345678 to the +# last 4 bytes. It then calls DVDReadAsync() and without waiting for the read to complete at all, +# it checks if the last 4 bytes are still 0x12345678. If they are, then the game fails. +# +# The check always passes on console because DVDReadAsync() -> issueCommand() calls +# DCInvalidateRange() (dcbi) on the read buffer. +# +# Dolphin cannot emulate this without an extremely significant performance hit. +# +# .text:800D2E64 lis r7, game_dvd_read_callback@ha +# .text:800D2E68 stw r0, 0(r17) # write 0x12345678 to the end of the buffer +# .text:800D2E6C mr r5, read_length # length +# .text:800D2E70 mr r6, read_offset # offset +# .text:800D2E74 addi r3, this, file.file_info # file_info +# .text:800D2E78 addi r4, r4, dvd_read_buf@l # addr +# .text:800D2E7C addi r7, r7, game_dvd_read_callback@l # callback +# .text:800D2E80 li r8, 2 # unknown +# .text:800D2E84 bl DVDReadAsync +# +$Fix file reads (dcache bypass) +0x800d2e68:dword:0x60000000