[U-Boot] Image copy to ram

[Mike Frysinger <vapier@gentoo.org>]

On Tuesday, April 12, 2011 14:47:46 Matthias Weisser wrote:
> Am 12.04.2011 18:20, schrieb Mike Frysinger:
> > On Tuesday, April 12, 2011 04:01:18 Matthias Wei?er wrote:
> >> I looked into the documentation but I can't find a command which copies
> >> an image from one address to another.
> > 
> > you mean 'cp' ?
> 
> Well, not exactly. cp doesn't know anything about the size of an image
> and is, compared to a simple memcpy or even an optimized version of
> memcpy, painfully slow which would eat up my expected performance
> improvements. A quick hack showed that a "imcpy" command could save me
> some 400ms on boot time which is about 50% of the total time spend in
> u-boot.

it prob makes more sense to make it an optional subcommand to bootm.  however, 
i wonder why even bother with the double reads.  if we assume that a valid crc 
is going to happen the vast majority of the time, we should tailor to that, 
and taking a perf hit in the edge cases where the crc is invalid is fine.

in other words, let's see about merging the decompression and verification 
steps so that there is only ever one read.

dont compression routines have crc checking built into them anyways ?
-mike
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