Linux on the Sega 32X. Who needs hardware synchronization primitives anyway?

After testing the waters with a Linux for Jaguar port; I basically set myself to get similar results on the 32X add-on for the Sega Genesis. Turns out that, even without hardware synchronization primitives, you can get smp-ready Linux: https://github.com/cakehonolulu/linux_ports

Neat to see this on HN after discussing this a bit with you on the Emudev discord (I'm Mask of Destiny there). I'm curious if you tested this on hardware. I think I mentioned this previously, but my understanding is that the SH-2s are incapable of writing to the cartridge area [0]. This would seem to preclude using the cart as RAM even with the extended "SSF2" mapper. Did you find that to be not the case or was this only tested in an emulator?

[0] - See this Spritesmind forum thread https://web.archive.org/web/20190209161834/http://gendev.spr... (Internet Archive link because the live site is mostly unusable due to the scraper deluge)

For those unfamiliar with the Hitachi SuperH architecture, imagine THUMB. ARM even had to license some of the patents from Hitchai when they developed THUMB. SuperH architecture is not the same thing as THUMB, but it has a lot in common, mainly use of 16-bit instructions, and instructions that only specify two registers rather than three.

But it also has some RISC jank of the era, such as branch delay slots.

These recent posts remind me of an earlier time in the 2000s when people were trying to boot Linux from anything computer-like

This is exciting! I didn’t see anything about I/O, but could the serial port be used for terminal access (or to drive keyboard input for the console). Lots of untapped potential.

With the Sega CD you’d get more RAM and a second, faster 68k