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68030 CPU cache

Random question...
In the Atari OS (TOS) for the TT030 there's a way to view/set the state of the 68030 cache. I've been curious to find out if the CPU cache is enabled when I'm in NetBSD. Anyone know, or know a quick way to to get the info at runtime w/o learning 68030 assembler? =)

David Ross

----- Original Message ----- From: "Ignatios Souvatzis" <is%netbsd.org@localhost>
To: <port-atari%netbsd.org@localhost>; <port-amiga%netbsd.org@localhost>
Sent: Sunday, January 18, 2009 11:05 PM
Subject: Re: gcc -m68060 option in kernel Makefiles


On Sun, Jan 18, 2009 at 05:45:42PM +0000, David Brownlee wrote:

I though the 040 added Move16? Whether or not thats useful in kernel or
even used by gcc is another matter...

Yes, 68040 and 68060 have MOVE16. We use them in the kernel's memcpy
for large blocks, I think, depending on CPU, but I hope they're not
directly used by gcc - they hook into the cache line write pipeline,
so effectively block normal writes why they execute. I don't know by
heart how they're ordered with respect to normal reads and writes.

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