Add TT_000 overlay from PSP (#1113)
TT_000 is the first overlay from PlayStation 1 that we are now able to
compile from the source and produce a 1:1 binary. This lead me to start
exploring the same overlay from the game Castlevania: Dracula X
Chronicles, which contains a PSP re-build of Symphony of the Night.
This PR adds all the infrastructure to add the same flow for a PSP
matching decomp. Use `export VERSION=pspeu` and then the usual `sotn`
command to splat the overlay, build it and check if it matches. Running
`make extract_disk` should not be necessary as the same ISO used from
`VERSION=hd` is also used for `pspeu`, so you will probably have it
extracted already.
Some important notes about the PSP build:
* The whole PSP build seems to be compiled with `-O0`, which makes it
much easier to decompile
* Having ŧhe PSX, PSP and Saturn builds will allow to easily
cross-reference the code and reduce fake matches
* `disks/pspeu/PSP_GAME/USRDIR/res/ps/hdbin/tt_000.bin` is the HD PSX
build
* `disks/pspeu/PSP_GAME/USRDIR/res/ps/PSPBIN/tt_000.bin` has the same
code from the HD build, but for PSP
* `disks/pspeu/PSP_GAME/USRDIR/res/ps/PACK_E/TP00.BIN` is the same as
above, but it packs both overlay and graphics. This is the file the PSP
game seems to actually use
* The PSP build uses the Metrowerk CodeWarrior's C compiler, which is
very different from the GCC one used on PSX.
* Thanks to @mkst lead, we found a way to still use the GNU assembler
and linker
* MWCC uses [wibo](https://github.com/decompals/WiBo/), a think
compatibility layer to run Windows CLI tools on Linux. It is much more
lightweight than Wine.
* MWCC does not support the `INCLUDE_ASM` dialect, so the custom
pre-processor `tools/mwcpp` had to be created
* The exact MWCC compiler version is unknown, but I suspect it is `build
147`
* I am not yet sure of any implications for using GNU AS and GNU LD
instead of the MW correspondent tools
* Not all the functions can be correctly disassembled, spimdisasm will
just produce a bunch of `.word 0x________` due to the in-progress effort
of adding the Allegrex-specific opcodes support
---
TO-DO list before marking the PR as ready:
- [X] Add PSP build to the CI
- [x] Add progress reporting to the PSP build
- [x] Integrate source file from `src/servant/tt_000_psp` to
`src/servant/tt_000` to promote the psp build as first-citizen
---
TO-DO in a follow-up PR:
* Figure out what `header` is: can we extract it as assembly code? or
maybe as custom re-compilable asset via splat? Is it a MW stuff or a
Castlevania-specific file?
* Get rid of the last line in `Makefile.psp.mk`
2024-04-21 01:18:10 +00:00
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