kamb205--KB-RPCS3/README.md

KB-RPCS3

Unofficial RPCS3 Port for PlayStation 5.

KB-RPCS3 runs RPCS3, the open-source PlayStation 3 emulator, as a native PS5 homebrew title. Its Mesa/RADV Vulkan renderer talks to the console directly, RPCS3's emulator core does the PlayStation 3 work, and a PS5-native shell provides the home screen, per-game settings and installers.

Alpha 0.1.0 is a source release. There is no downloadable PS5 package yet — the title's licence mix is unresolved, so a binary cannot be distributed. The source, the RPCS3 patch series and the build instructions are public. See Licensing status.

Unofficial. KB-RPCS3 is not made, endorsed or supported by the RPCS3 project or by Sony Interactive Entertainment. Please do not ask the RPCS3 team for help with it. "PlayStation", "PS3" and "PS5" are trade marks of Sony Interactive Entertainment Inc.

Contents

Downloads · Status · Features · Compatibility · Screenshots · Requirements · Installation · Performance · Building from source · Support · Credits · Licensing · Contributing · Disclaimer

Downloads

Source code (recommended)	KB-RPCS3-0.1.0-Source.tar.gz — the repository at tag v0.1.0-alpha, including the RPCS3 patch series, the PS5 title shell, tools and documentation
Repository	github.com/kamb205/KB-RPCS3
PS5 installable package	Not available. Distribution is pending a licence resolution (why); no binary is published, tested or promised

The source archive ships SHA-256 checksums on the release page.

Status of Alpha 0.1.0

KB-RPCS3 is an early alpha. This release publishes what exists — a working development build's source and a tested port — and is explicit about what has not been done yet.

• No PS5 binary is distributed. The title links RPCS3's GPL-2.0-only core with GPL-3.0 PS5 components; those licences cannot be combined in one distributed program. The current combined executable has an unresolved GPL compatibility issue and has not passed final PS5 testing.
• The exact Alpha 0.1.0 source has not finished console regression testing. Games were verified with the development build this release is based on; Alpha 0.1.0 adds speed/timing logging and off-by-default experimental options on top of that build.
• No performance improvement is claimed. The experimental SPU options are off by default and have not been measured at normal game speed.

Features

• RPCS3 on the console — the emulator core built for the PS5, rendering through Mesa/RADV Vulkan directly on the hardware.
• Native home screen (PPSA99303) with Games, Install, Settings and System tabs.
• Global and per-game settings, with recommended settings pulled from RPCS3's public configuration database when it is available.
• Installers for PS3 firmware (PS3UPDAT.PUP), PSN packages (.pkg) and licences (.rap).
• PS5 home-screen tiles that launch a game directly.
• DualSense controls, vibration, save data and trophy notifications.
• Benchmark tooling that records the effective game speed, so results can be shown to have been taken at normal speed.

Game compatibility

Verified on one PS5 Slim (firmware 13.60, etaHEN, kstuff lite, ShadowMountPlus) with the development build Alpha 0.1.0 is based on, at normal game speed (Clocks scale 100, Frame limit Auto):

Game	Serial	Result
LIMBO	HPEB00564	Playable — picture, sound and controls.
WWE '12	BLES01439	Playable — menus run near 60 FPS; matches slow down during big moves (CPU-limited).
Grand Theft Auto IV	BLES01128	Boots and plays, with substantial performance limitations — cutscenes at the game's own 30 FPS cap; roughly 13–27 FPS when driving, with occasional audio stutter. Needs "SPU XFloat Accuracy: Accurate" or cars fall through the road.

Every other PS3 game is untested on KB-RPCS3. RPCS3's own compatibility list is a hint, but the PS5's CPU is much slower than the PCs that list is based on. See COMPATIBILITY.md for the full qualification of these results, and KNOWN_ISSUES.md for limitations.

On older FPS numbers. During development some GTA IV benchmarks ran with Clocks scale 300 and Frame limit Off so the game's 30 FPS cap would not hide CPU cost; in that mode the game runs about three times too fast, so those numbers (around 20–22 FPS) are not normal-play results and are not quoted as such.

Screenshots

KB-RPCS3 does not publish fabricated screenshots. Genuine hardware captures will be added here once the Alpha 0.1.0 candidate has finished console regression testing and screenshots have been taken on a real console (L3 + R3 on the home screen saves one to rpcs3/screenshots/ on the title).

Until then, the safest visual reference is the title icon, shown here and shipped in the source at app/ps5/sce_sys/icon0.png:

_{Original KB-RPCS3 icon (alpha 0.1.0). Not a screenshot of gameplay.}

System requirements

To run a build (on the console):

Requirement	Notes
Jailbroken PS5	Developed and tested on a PS5 Slim, firmware 13.60
Homebrew enabler	etaHEN (FTP on port 1337, ELF loader on port 9021)
Kernel extension	kstuff lite — load once per console boot
Folder-title loader	ShadowMountPlus for titles under /data/homebrew/
Your own PS3 firmware	PS3UPDAT.PUP from Sony's PS3 update page
Your own games	PS3 discs as .iso/folders; PSN titles as .pkg + .rap

KB-RPCS3 includes none of the above. Other firmware versions and loaders may work but are untested.

To build from source: a Linux/arm64 host with the PS5 toolchain — see Building from source.

Installation

Alpha 0.1.0 has no downloadable build. Installation today means building it yourself from source, for your own use, then deploying the title folder. The full procedure is in INSTALL.md; in short:

1. Build the title (see Building from source).
2. Copy the built dist/PPSA99303/ folder to /data/homebrew/PPSA99303/ on the console (for example over etaHEN's FTP server).
3. Let ShadowMountPlus register it — KB-RPCS3 appears on the home screen.
4. Put PS3UPDAT.PUP in rpcs3/ inside the title folder and use Install → PS3 firmware.
5. Add games to rpcs3/games/ (disc images) or packages/ + exdata/ (PSN), then Install → Packages.

Do not redistribute a build you make: a combined binary cannot be distributed today (why).

Performance and known limitations

• CPU-bound, not GPU-bound. Demanding games are limited by how fast the PS5 runs emulated SPU code. GTA IV runs at roughly 13–27 FPS while driving.
• First-visit stutter. Entering a new area compiles SPU code and shaders; both are cached, so later visits are smoother.
• Normal speed needs Clocks scale 100 and Frame limit Auto. Per-game configs live in rpcs3/custom_configs/; other values change how fast games run.
• Native TLS does not work on the PS5 yet — KB-RPCS3 uses emulated TLS. Do not build with -fno-emulated-tls.
• It is an alpha: expect crashes. Keep a known-good build to fall back to (ROLLBACK.md).

The complete list is in KNOWN_ISSUES.md.

Building from source

KB-RPCS3 has two separately licensed parts, combined only at build time on your own machine:

Part	Folder	Licence
RPCS3 + the KB-RPCS3 core patches	port/rpcs3-patches/, applied to upstream RPCS3	GPL-2.0-only (RPCS3's licence)
The PS5 title shell (home screen, settings, installers, platform glue)	app/	mixed — MIT base, GPL-3.0-or-later UI and title code (app/LICENSING.md)

# 1. Fetch and patch upstream RPCS3 (revision 46aee28f8, 47 patches)
port/apply-rpcs3-patches.sh /path/to/rpcs3

# 2. Build the emulator core (about two hours on 8 cores)
SRC_DIR=/path/to/rpcs3 BUILD_DIR=/path/to/rpcs3-build JOBS=8 port/rpcs3-build.sh rpcs3_ps5

# 3. Build the PS5 title
APP_DIR=/path/to/app-build-copy RPCS3_BUILD_DIR=/path/to/rpcs3-build tools/vm-build-app.sh

The build scripts currently expect the PS5 toolchain and dependencies at fixed paths inside a build VM; BUILDING.md documents the exact layout, the dependencies and their licences, and the off-by-default experimental options. Read Licensing status before distributing anything you build.

Support KB-RPCS3

KB-RPCS3 is a free, open-source project developed in my spare time. If you'd like to support its ongoing development, you can buy me a coffee.

Support is entirely optional. KB-RPCS3 remains free and open source.

Credits

KB-RPCS3 stands entirely on other people's work:

• RPCS3 — the PlayStation 3 emulator, by the RPCS3 team and its many contributors. KB-RPCS3 is a port of it and does not exist without it.
• Mihawk — PS5_Vulkan (RADV/Mesa for PS5, the link recipe and libc.prx), the PS5 Vulkan Template and the PS5 platform layer.
• BlackBearReloaded — the ps5-homebrew-ui kit the home screen is drawn with.
• ps5-payload-dev — the PS5 payload SDK.
• Sascha Willems — the Vulkan example base the template builds on.
• The Mesa/RADV developers — the Vulkan driver.

Full authorship and licence details are in THIRD_PARTY_NOTICES.md.

Licensing

KB-RPCS3 is made of separately licensed parts:

• The RPCS3 patch series (port/rpcs3-patches/) is GPL-2.0-only, like RPCS3.
• The PS5 title shell in app/ is MIT and GPL-3.0-or-later per file.
• KB's own scripts are GPL-3.0-or-later unless a file says otherwise.

Because GPL-2.0-only and GPL-3.0 code cannot be combined in a distributed program, this release ships source only and no binary. The reasoning, the component inventory and the route to a lawful binary are in LICENSING_STATUS.md; the licence texts are in LICENSES/ and COPYING; per-file details are in app/LICENSING.md and THIRD_PARTY_NOTICES.md.

No PS3 or PS5 firmware, games, keys, system files or other Sony content is included. Use your own legally obtained firmware and games.

Contributing

Contributions are welcome once there is something concrete to work on. Read CONTRIBUTING.md first, then use the issue templates for bug reports and feature requests, or open a pull request with the template. Please report vulnerabilities privately as described in SECURITY.md, and follow the Code of Conduct. Planned work is in ROADMAP.md.

Disclaimer

KB-RPCS3 is an unofficial, non-commercial project. It is not affiliated with, authorised by, endorsed by or sponsored by Sony Interactive Entertainment Inc. or the RPCS3 project. "PlayStation", "PlayStation 3", "PS3" and "PS5" are trade marks of Sony Interactive Entertainment Inc.; "RPCS3" is the name of the RPCS3 project. No Sony logo, firmware, key or system file is included, and no endorsement by any party is implied. KB-RPCS3 does not provide, condone or support piracy — use your own legally obtained games and firmware.