Messages in this thread | | | Date | Thu, 5 Dec 2002 17:06:06 +1100 | From | David Gibson <> | Subject | Re: [RFC] generic device DMA implementation |
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On Thu, Dec 05, 2002 at 12:17:55PM +0900, Miles Bader wrote: > David Gibson <david@gibson.dropbear.id.au> writes: > > It seems the "try to get consistent memory, but otherwise give me > > inconsistent" is only useful on machines which: > > (1) Are not fully consisent, BUT > > (2) Can get consistent memory without disabling the cache, BUT > > (3) Not very much of it, so you might run out. > > > > The point is, there has to be an advantage to using consistent memory > > if it is available AND the possibility of it not being available. > ... > > Are there actually any machines with the properties described above? > > As I mentioned in my previous message, one of my platforms is like that > memory, which is only 2 megabytes in size.
Ok, that starts to make sense then (what platform is it, incidentally). Is using consistent memory actually faster than doing the cache flushes expliticly? Much?
-- David Gibson | For every complex problem there is a david@gibson.dropbear.id.au | solution which is simple, neat and | wrong. http://www.ozlabs.org/people/dgibson - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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