Subject: Re: Antwort: Re: blizzppc.device and NetBSD 1.3.2
To: port-amiga <port-amiga@netbsd.org>
From: Frank Wille <frank@phoenix.owl.de>
List: port-amiga
Date: 09/05/1998 16:42:07
Alexander Pokahr wrote:

> The PowerUp-board is just a PPC-processor, some RAM, and
> the PowerUp-kernel- software, which is the PowerUp-OS, and is different
> from the AmigaOS. The PowerPC is not able to access the DMA-RAM
> (Chip-RAM), so it is not possible to adress the custom-chips.

Nonsense.


> It might
> even be impossible for the PowerPC to adress the Zorro-bus, but i'm not
> sure of this.

The PowerPC on my CSPPC has access to the whole address space,
including Chip-RAM, hardware registers, Zorro bus, graphics
boards, etc...


> So, if you want to port NetBSD to PowerUp, you will have to write two
> kernels! One, that runs on the PowerPC, and one, that runs on the 680x0.

I would prefer a real PowerPC kernel. We can use the startup code
of one of the existing PPC kernels to initialize the PowerPC,
set up the MMU tables, etc. - then try to mix it with the Amiga
68k device drivers (there are only three or four files which con-
tain 68k assembler source, AFAIK). :)

Currently, I see only one big problem: the interrupts! I don't
know how the PPC could handle interrupts from the Amiga hardware.
Rumours say that the CSPPC is able to do that - at least the
developer boards definitely had this feature.


> AFAIK there is a beta-state linux-ppc kernel for PowerUp, but i havent
> tested it, and dont know, how it works. But if anyone is interested in
> doing a PowerUp port of NetBSD, he should have a look at it.

Is the source available? I was not able to find it.

--
   _  Frank Wille (frank@phoenix.owl.de)
_ //  http://fiction.pb.owl.de/~frank/
\X/   Phx @ #AmigaGer