I suggest that you go to matermost and talk to the devs.
Please keep the Windows classic 9x/2000 look and feel.
The layman's guides - debugging - bug reporting - compiling - ISO remaster.
They may help you with a problem, so do have a look at them.
Feel free to improve the cross-platform things like IPI management, scheduling and whatever. Nobody's working on this, because it comes after all the platform-specific HAL stuff, and that's largely missing on x86 (which is what most devs would be working on when diving into SMP).
But I can't even find tech data like what ports to probe, how to set modes, or other things about how to enter multicore, how to swap between cores, how to communicate between cores, etc.
That sounds x86-specific... https://wiki.osdev.org/Symmetric_Multiprocessing -- you get information about the processors and their local APICs using ACPI (Windows also has an MPS HAL but I see no reason for us to support that), then configure the APICs and send an init IPI to each CPU.
Which means in ROS the first step is to get the APIC HAL into a working state.
But that of course has nothing to do with what the OP was asking about, since an RPi has none of those things.
Yes Thomas, I somehow missed the ARM part... And I can see MPS as useful if the APIC HAL cannot initialize, but the ACPI HAL should obviously be the priority. Thanks, and my apologies for posting in this thread.
I'd say you may as well skip MPS most of the machines that supported this are quite vintage, and often enough fail to even boot or require repairs (I have one or two like this). Nevertheless if it does get supported it would be nice. ACPI HAL and APIC support is where SMP work is needed.
APIC is a chip Advanced Programmable Interrupt Controller... either part of the chipset or internal to the processor not really related to ACPI. Except that you need an ACPI driver to use it typically.