[libre-riscv-dev] LibreSOC - RISCV and POWER dual architecture feasibility

[Jacob Lifshay]

On Mon, Mar 16, 2020, 00:13 Lauri Kasanen <cand at gmx.com> wrote:

> On Sun, 15 Mar 2020 12:43:45 -0700
> Jacob Lifshay <programmerjake at gmail.com> wrote:
>
> > Later (for Libre-SOC v2 or v3), it might be a good idea to add support
> for
> > x86 and x86_64 user-mode since the patents for the base ISA will have
> > expired by then. This would help give us an advantage since it would
> allow
> > us to run legacy software.
>
> 486 and 586 patents had expired years ago, and we had Chinese 1 GHz
> implementations of those (vortex86). Now they have 686 models, so I
> take pentium pro patents are also up for use.
>
> x86_64 should become free around 2022 by my estimation.
>

The amd64 spec was first published in august 2000 according to wikipedia,
so that may mean the base ISA patents expire in 2020.

Jacob