I'm trying to test the cache on my beagle with a snapshot from the git tree today. I tried it out by loading a file from the mmc with dcache off and then dcache on. I didn't see any difference in speed. After reading this commit (http://git.denx.de/?p=u-boot.git;a=commit;h=95c6f6d), I expected to see a performance improvement.
This is a capture of how I tested it...
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OMAP3 beagleboard.org # mmc init 1 mmc1 is available OMAP3 beagleboard.org # dcache Data (writethrough) Cache is OFF OMAP3 beagleboard.org # fatload mmc 0:1 0x80000000 uImage.bin reading uImage.bin
3852836 bytes read OMAP3 beagleboard.org # dcache on Data (writethrough) Cache is ON OMAP3 beagleboard.org # fatload mmc 0:1 0x80000000 uImage.bin reading uImage.bin
3852836 bytes read OMAP3 beagleboard.org #
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