Re: AB and MagiC

From: Doug Little <doug_at_innerworkings.co.uk>
Date: Sun, 18 Jan 1998 23:52:02 -0000

>> What toolkit 5.07 setup will allow me to run MagiC? I've tried with
>> 1 or 2 two SIMMs enabled. The problem is either the MAGXBOOT program
>> runs and then never gets past the initial blank reboot screen, or
>> it aborts on 2 bombs and the Falcon boots without MagiC. Right now
>> I'm getting the blank screen. I know there were/are problems with
>> TK 5.x and MagiC. Have they been resolved?
>
>Ask Magic's authors - Doug said many times that it's MagiC's bug.


It's not a Magic 'bug' - it's just a nasty feature programmed into the
kernel which
stops the fastram buffer from being located by 3rd party software. They've
hidden
the SCSI DMA buffer, so TK cannot modify it's cpu-cacheability until
somebody
finds a way to locate the hidden buffer in a reliable manner.

There is a fudge that lets you get around it, but I can't remember what it
is. I think
it involves using DMASNOOP before MAGXBOOT to make sure all ST-ram is
non-cacheable before Magic tries to grab any of it.

The exact running order I can't recall - but it should be easy enough to
find. It
should only involve TK, MAGXBOOT & DMASNOOP.

Failing that, turn off the CPU caches in the TK driver and fiddle around
until
Magic loads. Then you can worry about fastram-buffer cacheing problems
later.

Doug.
Received on ma. jan. 19 1998 - 10:07:00 CET