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From: Andre Puschman <andre.puschmann@imms.de>
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Subject: Re: flash read performance
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Jamie Lokier schrieb:
> I don't know much about this area, but will _writing_ to the flash
> work reliably if ioremap_cached() is used?
>
> -- Jamie
>   

Good point. I only was into reading and so I totally forgot writing ;-)
I gave it a try, although it was terribly slow (only a few kb/s), it worked.
I just did a cp uImage /dev/mtd3. On the other hand, I never tried writing
with the old driver. So I don't know if this is faster.

I also did some more testing with my improved flash-timing parameters,
which yields to read speeds of up to 18-19MB/s, which is really fast 
compared
to 1,3MB/s at the beginning :-)

So for now, this is my result:
- cache and well chosen flash-timings have great impact on (at least) 
read performance

But I think transfer rates > 20MB are possible ..

Anyway, with these results, booting the complete system in nearly (or 
even less than) 2s should be possible.

Regards,
Andre