Re: MOL

[Alan B. <al...@ms...>]

hi,

> I'm currently considering porting MOL to other platforms
> than Linux/PPC (primarily *BSD and Darwin). Before doing that 
> however, I though it might be nice to have it working on APUS.

good idea :-)
 
> - Does the BK kernels at fsmlabs contain working APUS support?

dont know.... BK changes get integrated into the APUS CVS (held at
sourceforge)...i dont think theres a reversal.
 
> - Any special quirks? In particular, why is the kernel
> *not* located at physical address 0?

LinuxAPUS-capable Amigas are of two varieties.... those with 2Mb of
ChipRAM and those with 1Mb of ChipRAM. This ChipRAM is what used to make
the Amiga so very good at its sound and gfx..its memory addressable
directly by the custom chips...and therefore if the CPU has to use it, it
falls into contention...having to wait 2 clockcycles for access.. it also
runs at a slow rate and is of slow speed.  A large chunk of that ChipRAM
is also used by the framebuffer for display (if the Amiga concerned does
not have a gfx card) and for sound (ditto - no sound card installed). 
from memory (no pun intended) its 1.2Mb taken up for custom chip
utilisation on an 'AGA' (2Mb installed) machine.

FastRAM is memory only accessible by the CPU..hence its name. there is no
contention with the cusotm chips, its local to the CPU on the PowerPC
cards and its usually the 60ns flavour. 

memory access speeds (measured under AmigaOS) are something like  ~8Mb/s
for ChipRAM and 40Mb/s upwards (depending on operation) for FastRAM
(604 PowerPC cards on Amigas get around 80Mb/s iirC)

 > - Which cpu flavors are used? MOL currently lacks 603(e) support,

no!!!! argh. when did this drop out? Whilst I was looking at MOL there was
603(e) support...but the kernel required a run-time patching...and hooks
were installed into the kernel to allow this.

 > but I intend to add support for this processor shortly. > 

great! this is what I have.

> To be able to add APUS support, I obviously need help with
> testing and debugging since I don't have an APUS box.

I can help you out...having the required machine AND MacOS CD's lying next
to it.
 
alan