Subject: Re: CVS commit: syssrc
To: Ignatios Souvatzis <firstname.lastname@example.org>
From: David Brownlee <email@example.com>
Date: 06/03/2000 15:42:55
On Mon, 15 May 2000, Ignatios Souvatzis wrote:
> On Mon, May 15, 2000 at 12:29:47AM -0400, Kevin P. Neal wrote:
> > On Sun, May 14, 2000 at 06:37:53PM -0700, Jason R Thorpe wrote:
> > > Do the systems that have problems with `tas' also have problems with
> > > `cas'? If `cas' is okay, I can write a version that uses `cas' (tho
> > > I think it might be one or two instructions longer :-)
> > I think the restriction, at least on the Amiga, was that no instruction
> > should be used that used the "special read-modify-write bus cycle."
> Yes. This is correct. For _the_ Amiga. (later called Amiga 1000), which has
> only chipmem. (that is, memory controlled by the Fancy Amiga DMA Engine).
> Machines with seperated fastmem and chipmem (e.g. any with cpu accellerators
> that also provide memory, and A3000 and A4000 (and the DraCo, which has no
> "real" chipmem) are safe as long as fastmem ist used.
Would it make sense to leave this as a compile time option, so
specifically targetted kernels can take advantage of tas where
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