fix: correct supafaust PPU thread affinity for tg5050#784
Closed
carroarmato0 wants to merge 1 commit into
Closed
Conversation
On tg5050 (Smart Pro S), only CPUs 0, 1, and 4 are online at game launch time. The SUPA pak default.cfg was copied from the tg5040 config which sets supafaust_thread_affinity_ppu to 0xc (CPUs 2+3), but those CPUs are offline on tg5050. supafaust's Thread_SetAffinity calls pthread_setaffinity_np with the requested mask. When any CPU in the mask is offline, the call fails and the core throws Mednafen::MDFN_Error during retro_load_game, crashing the emulator before the game can start. Fix by setting the PPU thread affinity to 0x10 (CPU 4), which is online on tg5050. The emulation thread stays on 0x3 (CPUs 0+1), preserving the same emu/PPU separation as on tg5040. The bug was introduced in 89158fe when tg5050 support was added and the tg5040 affinity values were used verbatim without accounting for the different CPU topology.
carroarmato0
commented
Jul 18, 2026
carroarmato0
left a comment
carroarmato0
left a comment
Collaborator
Author
There was a problem hiding this comment.
I realized this might require some more thinking through as the governor might dynamically disable the CPU we just added, not solving the core problem. Created an issue instead to discuss
carroarmato0
added a commit
to carroarmato0/NextUI
that referenced
this pull request
Jul 26, 2026
Two related fixes: 1. skeleton/EXTRAS/Emus/tg5050/SUPA.pak/default.cfg: change supafaust_thread_affinity_ppu from 0xc (CPUs 2+3, offline on tg5050) to 0x10 (CPU 4, online). Mirrors the upstream fix in PR LoveRetro#784. 2. workspace/all/minarch/ma_core.cpp: wrap retro_load_game in try/catch in Core_load(). A core that throws during load now logs the exception and exits cleanly instead of hitting std::terminate with no context. (C++ only; upstream's ma_core.c has no equivalent guard available.)
carroarmato0
added a commit
to carroarmato0/NextUI
that referenced
this pull request
Jul 26, 2026
The C++20 migration PR must not change behavior. Commit 8f873ec had slipped in a tg5050-specific crash workaround (supafaust_thread_affinity_ppu 0xc->0x10, the LoveRetro#785/LoveRetro#784 fix) that belongs in its own change, not this migration. Restore it to upstream's 0xc so the PR stays behavior-neutral.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
SNES games crash immediately on launch on the Smart Pro S (tg5050). The emulator exits with
terminate called after throwing an instance of 'Mednafen::MDFN_Error'before the game loop starts.On tg5050 (sun55iw3 / Allwinner T527), only CPUs 0, 1, and 4 are online at game launch time:
The SUPA pak
default.cfgwas copied from the tg5040 config when tg5050 support was added (89158fe), using the same affinity values tuned for tg5040's quad-core layout:supafaust's
Thread_SetAffinitycallspthread_setaffinity_npwith the requested mask. When any CPU in the mask is offline,EINVALis returned and the core throwsMednafen::MDFN_Errorfrom insideretro_load_game, which propagates up and crashes the emulator before the game starts.Changed the tg5050 PPU thread affinity to
0x10(CPU 4), which is reliably online on tg5050:This preserves the same principle as tg5040 (emulation and PPU threads on separate CPUs) while using the correct CPU for the tg5050 topology.
Tested on physical Smart Pro S hardware. SNES games that previously crashed immediately now launch and run correctly.