[U-Boot] JFFS2 with NAND flash is very SLOW ...

[Stefan Roese]

On Tuesday 02 June 2009 15:23:57 Pierre Savary wrote:
> Is it better to use or not D-cache and I-cache?

Depends a bit on the "application". From my experience I-Cache is most 
important. But for memory intensive applications (JFFS2 might be such a beast) 
D-cache could be very helpful as well. Best is to have both enabled of course.

> Currently, in my config file, I have only
> #define CONFIG_CMD_CACHE
> What do I have to add?

Defining the cache commands doesn't insure that caches are really enabled. 
Some platforms don't support I- and/or D-cache in U-Boot. I can only speak for 
PPC4xx which has I-cache enabled and "usually" D-cache disabled (because of 
cache-coherency issues). This might be different on your platform. Again, just 
enabling the cache commands will most likely not help here.

Best regards,
Stefan

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