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From: Terry Lambert <terry@lambert.org>
Message-Id: <199509061954.MAA00541@phaeton.artisoft.com>
Subject: Re: Cyrix cache enable patches?
To: gibbs@freefall.freebsd.org (Justin T. Gibbs)
Date: Wed, 6 Sep 1995 12:54:58 -0700 (MST)
Cc: hackers@freefall.freebsd.org
In-Reply-To: <199509061746.KAA14927@freefall.freebsd.org> from "Justin T. Gibbs" at Sep 6, 95 10:46:40 am
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> 
> Did anyone look at integrating these patches?

Cyrix doesn't honor the non-cacheable bit.

It would be silly to integrate patches to turn it on without integrating
detect as a global setting and doing a BINVD when a read is issued to
get around it not honoring the non-cacheable bit.

You *aren't* going to get a cache update, since the motherboard chipset
doesn't notify the chip of a bus mastering DMA causing a cache invalidation
to be necessary (no pin on the chip for it).


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.