Intel is mulling the development of a new 64-bit mode-only architecture called x86S, according to a white paper that the company has published online to solicit feedback for the project and outline its benefits, which aim to reduce “the overall complexity of the software and hardware architecture.” A roadmap that surfaced online today would also suggest that Intel has canceled its 6P+8E Meteor Lake-S desktop CPUs, although the person who leaked it, @OneRaichu, has claimed that this family has been canceled entirely, with Arrow Lake-S CPUs being their replacement. Arrow Lake-S CPUs aren’t expected to release in 2024 and will reportedly max out at only 14 cores and 20 threads, substantially less than what the current Raptor Lake-S family has to offer.
Intel: Benefits of a 64-Bit Mode-Only Architecture
- Using the simplified segmentation model of 64-bit for segmentation support for 32-bit applications, matching what modern operating systems already use.
- Removing ring 1 and 2 (which are unused by modern software) and obsolete segmentation features like gates.
- Removing 16-bit addressing support.
- Eliminating support for ring 3 I/O port accesses.
- Eliminating string port I/O, which supported an obsolete CPU-driven I/O model.
- Limiting local interrupt controller (APIC) use to X2APIC and remove legacy 8259 support.
- Removing some unused operating system mode bits.
From an Intel post:
This whitepaper details the architectural enhancements and modifications that Intel is currently investigating for a 64-bit mode-only architecture referred to as x86S (for simplification). Intel is publishing this paper to solicit feedback from the ecosystem while exploring the benefits of extending the ISA transition to a 64-bit mode-only solution.
A 64-bit mode-only architecture removes some older appendages of the architecture, reducing the overall complexity of the software and hardware architecture. By exploring a 64-bit mode-only architecture, other changes that are aligned with modern software deployment could be made.