Subject: Re: PowerPC 601 versus the others
To: Lloyd Parkes <firstname.lastname@example.org>
From: Bill Studenmund <email@example.com>
Date: 01/15/2002 09:39:39
On Tue, 15 Jan 2002, Lloyd Parkes wrote:
> I have been reading through the MPC601 manual and some PowerPC manuals,
> and I can't see much standing in the way of NetBSD on the 601. The only
> changes that I spotted were in some bit definitions in the MMU.
> Am I missing something, or is that the only thing preventing NetBSD from
> being ported to 601 based machines.
There are a number of PPC instructions which aren't implimented. According
to my 601 manual (MPC601UM/AD Rev 1), they are:
fres, frsqrtefsel, fsqrt, fsqrts, mfspr(*), mftb, mtspr(*), stfiwx, tlbia,
(*) some of the spr's are different. Mainly the BAT ones and TB & TBU.
tlbia and tlbsync are supervisor instructions, so we don't need to emulate
There are also a number of 64-bit ppc instructions not implimented, but I
think they would cause exceptions now, so we don't need to emulate them.