Port-m68k archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: Question about caching




On Aug 27, 2009, at 12:43 PM, Michael van Elst wrote:

agrier%poofygoof.com@localhost ("Aaron J. Grier") writes:

On Thu, Aug 27, 2009 at 11:03:55AM -0700, Jason Thorpe wrote:
Ping?  Does no one else remember either? :-)

wow, MMU _and_ cache!  :)

which 68k variants we talking about here?

Every single 68k that runs NetBSD.

To answer the question, the chip should generate the bus cycles
that you ask it for. If you use a mapping that inhibits caching
then you get 1:1 bus cycles, if you use a mapping that allows
caching you get cache fill and push cycles. Using two mappings
to the same physical address but with different cache modes
rarely makes no sense.

I'm mostly interested in coherency of regular memory with cached vs uncached mappings.


--
--
                               Michael van Elst
Internet: mlelstv%serpens.de@localhost
"A potential Snark may lurk in every tree."

-- thorpej



Home | Main Index | Thread Index | Old Index