Re: [PATCH 1/2] ARM: Add Kconfig option to use mkimage -T kernel_noload

[Andre Renaud <andre-7Wk5F4Od5/oYd5yxfr4S2w@public.gmane.org>]

On 01/03/12 08:59, Stephen Warren wrote:
> Uwe Kleine-König wrote at Wednesday, February 29, 2012 12:44 PM:
> ...
>> If you want to give incentive for U-Boot to improve, drop the target
>> today. And note that at least people caring about boot time must not use
>> the kernel's uImage target anyhow.
> 
> If you enable the new config option in this patch, then the performance
> issue is solved; U-Boot doesn't copy the kernel image any more, and the
> kernel decompressor can write directly to the appropriate location without
> moving the image first (assuming your board boot script loads the uImage
> to a non-conflicting address).

I may have missed part of this, but isn't one of the points regarding
this that the zImage decompressor always runs with data cache disabled,
resulting in a slow decompress, where as if the U-Boot decompressor is
used (ie, gzipping the Image, and telling U-Boot to decompress), then it
can run with caches enabled, improving boot speed?

Thus the relocation issue is not really the speed hit, rather it is the
image decompression.

Regards,
Andre