Research record

Evidence cutoff: 2026-07-17. Only primary upstream repositories and release metadata are used below. Each statement is labelled FACT, INFERENCE, or UNKNOWN.

Evidence snapshot

PS5 Payload SDK

FACT: release v0.41 maps to commit d2e2e585740362976a39fdd5ccf390f199a7bc37 and was published on 2026-06-28. Release
FACT: GitHub's releases/latest endpoint still resolved to v0.41 on 2026-07-17.
FACT: GitHub release metadata reports ps5-payload-sdk.zip SHA-256 ebfb0acb5260511951a80e17db41650c62d20a8caf8659a230b928dc85005984.
FACT: sce_stubs/libSceGnmDriver.c contains 158 export stubs, including submit, draw, dispatch, compute-queue, embedded-shader, resource-registration, and synchronization-related names. The file is assembly labels only and does not establish C signatures. Pinned stub
FACT: the pinned SDK tree has no public GNM header and no GNM/GPU sample. Its only GNM-named source files are the driver stub sets.
FACT: the SDK's hello_dlfcn sample demonstrates dlopen, dlsym, and dlclose; hello_so demonstrates shared-object linking/loading. Dynamic-loading sample
FACT: the pinned payload CRT calls __patch_init before main; crt/patch.c writes process credential capability/attribute fields and syscall-address bounds through SDK kernel read/write primitives. Pinned CRT startup Pinned patch code
FACT: the pinned rtld's SPRX path can call sceKernelLoadStartModule/sceKernelStopUnloadModule; the SPRX-specific init and fini callbacks are empty in SDK source, but the system calls' internal side effects are not established. Pinned SPRX loader
FACT: crt/Makefile partially links 12 source objects into crt1.o; the other six installed CRT-named files are empty archives at v0.41.
FACT: the prospero-clang wrapper omits crt1.o for -nostartfiles and omits libc/kernel/Sce default libraries for -nodefaultlibs. An offline -### trace confirms both suppressions without producing an ELF.
FACT: the SDK README points to external ELF-loader projects, but the exact loader used for firmware 9.60 and its caller source are not part of the SDK or the pinned local evidence set.
FACT: unless otherwise marked, the SDK is GPLv3-or-later; FreeBSD headers retain their BSD licenses. SDK README

PS5 SDL2 fork

FACT: inspected commit 0baf4ac49382b537ba449901b5b6d0d189bb1fbb, dated 2026-07-07. Commit
FACT: src/video/ps5 implements a CPU framebuffer/VideoOut path and an OSMesa context path. VideoOut registration and flip occur in the SDL backend, not in chimera-gfx Phase 0. PS5 video
FACT: that backend owns direct-memory allocation, buffer tiling, registration, flip submission, event waiting, and cleanup. Its public source declares opaque VideoOut structures with junk fields; those layouts are not copied into this project.
FACT: SDL is Zlib-licensed at the pinned commit. The PacBrew recipe's license=('LGPL') metadata conflicts with upstream LICENSE.txt; this project follows the primary upstream license file.
FACT: the native audio backend forces 48 kHz and uses AudioOut. PS5 audio
FACT: native PS5 source directories exist for joystick, keyboard/IME, filesystem, audio, video, and main; joystick code includes vibration and light-bar operations. PS5 joystick

PacBrew

FACT: inspected commit c2abcfcb60f569128abd0e8e70ad03a67bee5ea7, dated 2026-07-07. Repository
FACT: the SDL2 recipe enables SDL_OPENGL and SDL_LOADSO but follows an unpinned Git source with sha256sums=('SKIP'); this project therefore does not treat that recipe as reproducible pinning. SDL2 recipe
FACT: the Mesa 22.1.7 recipe enables OSMesa and gallium swrast, while Vulkan, EGL, GBM, GLX, and GLES are disabled. Mesa recipe
FACT: package recipes exist for FBNeo, LakeSnes, Mednafen, DevilutionX, and EDuke32. Their presence proves port work, not native GPU acceleration.

RetroArch

FACT: inspected commit 32ee70cef5d4bdc32a4ca3b3b261209ce74b6e81, dated 2026-07-16. Commit
FACT: the tree contains an SDL2 video driver and dynamic-library support used for libretro cores. SDL2 driver
FACT: Makefile.orbis, platform_orbis.c, and an Orbis context driver are available as PS4 integration references.
INFERENCE: those PS4 files are useful for frontend lifecycle and build concepts only. Their GPU assumptions must not be transferred to PS5.

PS5 Linux

FACT: inspected ps5-linux-loader commit 8e7dd40df6144bed6194d165d48aa9468a7e13f3, dated 2026-07-10. Repository
FACT: the loader targets a Linux kernel/initramfs boot flow and references patched Linux components.
INFERENCE: Linux amdgpu/RADV progress demonstrates that the hardware can be driven under a custom Linux stack; it does not provide a native PS5 userland ABI or a reusable driver implementation for this project.

ABI evidence table

Class	Area	Primary evidence	What the evidence supports	Policy
FACT	Export names	SDK `libSceGnmDriver.c`	names exist in the v0.41 stub set	resolve only
FACT	Target ISA	public SDK toolchain	compile target is x86-64 PS5 userland	does not prove a function ABI
INFERENCE	Runtime module name	stub filename plus SDK `.sprx` convention	`libSceGnmDriver.sprx` is a candidate	load only behind gates
UNKNOWN	GNM signatures	no pinned public header	no callable prototype is proven	never call
UNKNOWN	GNM structures	no pinned public definition	no layout is proven	never construct
UNKNOWN	Firmware stability	no public compatibility matrix	9.60 is a build identifier, not known compatible firmware	9.60 build only; never infer compatibility
FACT	SDK payload startup	pinned `crt/crt.c` and `crt/patch.c`	pre-main kernel process-state writes occur	execution blocked
FACT/UNKNOWN	SPRX loader lifecycle	pinned rtld source/system-module implementation boundary	load/start and stop/unload are requested; system internals unknown	offline audit only
UNKNOWN	Embedded-shader semantics	export names only	no identifier or binary contract	never call
UNKNOWN	Submission/sync semantics	export names only	no ownership or timeout contract	never call
FACT	SDL2 public API	pinned SDL headers and `LICENSE.txt`	application API and Zlib terms at that commit	Phase-1 candidate only
FACT	Pinned SDL implementation	pinned PS5 SDL source	exact source-level VideoOut sequence at that commit	indirect through SDL only
UNKNOWN	SDL runtime behavior	no approved observation	firmware compatibility, timeout, and cleanup on PS5	do not execute
FACT/UNKNOWN	minimal startup	compiler can omit stock CRT; exact loader caller is absent	source-level omission only, not safe return	do not build an ELF

The complete Phase-0 lookup subset and per-symbol evidence are in manifests/ps5_gnm_symbols.json. Symbol presence never upgrades ABI confidence.

Unknowns register

ID	Unknown	Why it blocks progress	Evidence needed
U-001	exact signatures for every candidate GNM export	a wrong call can corrupt memory immediately	acceptable public header/source or independently validated ABI evidence
U-002	command-buffer and packet formats	cannot safely build GPU work	public, licensed format evidence plus review
U-003	GPU-visible memory allocation and cache rules	resources may alias or be incoherent	proven userland allocation contract
U-004	resource registration ownership/lifetime	cleanup and crash safety are unknown	proven signatures and lifecycle evidence
U-005	queue, fence, and timeout semantics	a wait or queue action could hang	bounded synchronization contract
U-006	VideoOut/GNM buffer compatibility	presentation ownership is unknown	separate, minimal Phase-1 evidence
U-007	embedded shader identifiers and binary contract	cannot safely bind a shader	licensed public evidence and test plan
U-008	runtime module name across firmware	even discovery may fail	approved hardware observation per firmware
U-009	system-module initialization side effects	SDK call chain is known; firmware module internals are not public	acceptable public evidence plus separately approved observation
U-010	supported firmware set	no hardware evidence exists	one manually approved probe at a time
U-011	bounded SDL flip-event wait	safe timeout/cleanup cannot be guaranteed	licensed bounded-wait change or proven supervisor semantics
U-012	SDL cleanup after forced process termination	recovery behavior is unknown	approved observation or public lifecycle evidence
U-013	kernelwrite-free PS5 payload startup	SDK v0.41 CRT patches kernel process state before `main`; Phase 0.5 cannot prove a safe replacement	exact pinned loader caller plus complete entry/return/cleanup/crash audit
U-014	loader changes before `_start`	incoming args already expose kernel access, but the creation path is absent	exact loader source and configuration used for firmware 9.60

Unknowns are closed only by updating this file, the relevant ADR, and the firmware matrix with a primary source or an explicitly approved observation.

Assumptions register

Assumptions are design choices, not compatibility claims.

ID	Assumption	Scope	Falsification or review trigger
A-001	`libSceGnmDriver.sprx` is a useful runtime candidate	discovery-only probe	approved lookup fails or a public source establishes another module
A-002	Mock limits of 4096 pixels and 16 live resources are sufficient for lifecycle tests	host tests only	an adapter test requires a larger deterministic bound
A-003	RGBA8 is enough to stabilize the initial public upload contract	mock and software-frame planning	RetroArch/SDL integration proves another minimum format is required
A-004	The existing SDL CPU-framebuffer route is safer than duplicating its opaque VideoOut layout	first Phase-1 design	official public VideoOut headers and bounded lifecycle become available
A-005	1920x1080 and one fixed frame minimize first-test state	disabled Phase-1 candidate	exact firmware/display evidence requires a different supported mode
A-006	A firmware-specific rebuild must receive a new approval because its digest changes	all hardware candidates	never relaxed; enforced artifact-provenance rule

12 KiB Raw Blame History