Reviving FPU Emulation for i486SX on NetBSD 10

In a remarkable feat of retro-computing engineering, Mikhail Zakharov has successfully resurrected support for x87 floating-point unit (FPU) emulation in the NetBSD kernel, targeting legacy 486SX-class processors without hardware FPUs. This groundbreaking project renews the original MATH_EMULATE option in NetBSD 10.x and beyond, bringing back a crucial feature that was thought to be lost forever.

As part of this initiative, Zakharov has also revised and reverted changes introduced in commit dfe83e0, which inadvertently removed FPU emulation support from the kernel. This reversal is a testament to the dedication and expertise of the NetBSD community, as well as Zakharov's own perseverance in the face of technical challenges.

It is essential to note that this project is still in its infancy, and users are advised to exercise caution when using it. The author acknowledges that the code may contain bugs or incomplete functionality, and therefore disclaims any responsibility for issues caused by its use.

A highlight of this project is the inclusion of logarithmic and special math operations check releases for the compiled NetBSD kernel with FPU-emulation as well as a drive image. This ensures that users can enjoy seamless performance with their 486SX-class processors, now equipped with the functionality they once had.

For those interested in contributing to or exploring this project further, Zakharov invites suggestions, questions, and bug reports through an issue tracker or direct contact. The author is grateful for any help that can be provided to improve the quality and stability of this innovative work.

Finally, it's worth mentioning that Zakharov's modifications to the original code by Linus Torvalds, William "Bill" Jolitz, and NetBSD are licensed under the BSD-2-Clause license. This ensures that the work remains accessible and open-source, allowing others to build upon and contribute to this exciting project.

Get Involved

If you have any ideas, questions, or concerns about this project, please don't hesitate to reach out. Zakharov is committed to continuing this work and appreciates all forms of support and collaboration.

Contact Information

Mikhail Zakharov - mikhail.zakharov@gmail.com