If homebrew is launched directly after NSMB 2, GPU commands aren't being executed anymore
KonPet opened this issue · comments
To reproduce this bug just launch New Super Mario Bros 2, and afterwards any other homebrew game. Now, after initializing the GPU, no gpu commands (like GX_MemoryFill) seem to go through. The functions also never return any errors. And as soon as you start doing more stuff, like drawing a frame, the gpu crashes completely. Despite trying for quite a while I wasn't able to figure out how to fix the crash, I simply don't know enough about how the GPU works.
While looking into the source code I noticed another oddity by the way. Calling GX_MemoryFill and only using the 2nd buffer doesn't work, as the event for a single memory fill being done on channel two is surpressed in source/gpu/gxqueue.c, line 29. Removing the check for that specific event doesn't seem to affect anything, though I haven't thouroughly tested that and I might be missing something. This doesn't matter much, only if the first buffer is busy for some reason so you want to use the second one.
I think I just reproduced this on my N3DSXL.
- Launched NSMB2
- Pressed Home
- Launched mGBA from the home screen
- Pressed (A) to confirm closing NSMB2 and launching mGBA
- The homebrew animation plays, then a black screen, then the screen is covered in noise.
I was able to take a screenshot with Luma but could not exit the application with the home button and had to use the Luma menu to reboot.
