Subject: Re: ROM glue
To: Olivier GALIBERT <Olivier.Galibert@mines.u-nancy.fr>
From: Allen Briggs <briggs@puma.bevd.blacksburg.va.us>
List: port-mac68k
Date: 12/14/1995 09:04:03
> I'm in the process of porting macbsd to a performa 630 (yeah, the one
> with the IDE drive...)
Fantastic!
> - To find out vectors for the 630, I get the asm code at the ROM
> entry points for a LCIII and look for then in the 630's one (I
> just love Rommie ;-). A problem is that vectors for the LC
> series are of the form 408xxxxx and 40Axxxxx. Since the ROM
> is 1Mo and starts at 40800000, they should stop at 408FFFFF. So
> how is the MMU mapping the rom ?
Hmm... Good question. The ROM itself is actually mapping 16MB. Why?
"Because that's plenty for any mac." That could probably be dropped
back to 1MB since I think the only macs to use more than that are the
PowerMacs.
> - I noticed in the code that some vectors are said "verified" and
> others not. What should I test to know if my guesses can achieve
> the verified status ?
I'm afraid I can't answer this other than, "if they work, they're
verified." Many of them can be checked with MacsBug, though. At
least, ReadXPRam is a symbol that my MacsBug can find....
> - I hacked with a battleaxe mkfs, install and the 1.8 booter
Neat. They were forged with a battleaxe, too... ;-) If the Performa
630 is an 040-based machine, you'll want to pick up the 1.9 booter--at
least the called to flush the instruction caches. I had a number of
bizarre problems while working on the Q700 until I found that bug...
-allen
--
Allen Briggs - end killing - allen.briggs@bev.net ** MacBSD == NetBSD/mac68k **
Where does all my time go? <a href="http://www.netbsd.org/">Guess.</a>