[U-Boot] [PATCH] ext2load: increase read speed

[Eric Nelson]

On 03/28/2012 07:37 AM, Jason Cooper wrote:
> This patch dramatically drops the amount of time u-boot needs to read a
> file from an ext2 partition.  On a typical 2 to 5 MB file (kernels and
> initrds) it goes from tens of seconds to a couple seconds.
>
> All we are doing here is grouping contiguous blocks into one read.
>
> Boot tested on Globalscale Technologies Dreamplug (Kirkwood ARM SoC)
> with three different files.  sha1sums were calculated in Linux
> userspace, and then confirmed after ext2load.
>
> Signed-off-by: Jason Cooper<u-boot at lakedaemon.net>

Tested-by: Eric Nelson <eric.nelson at boundarydevices.com>

Tested on i.MX6 Sabre Lite board loading a file of ~900k:

Without patch:

	MX6QSABRELITE U-Boot > time ext2load sata 0:1 12000000 
/usr/lib/libperl.so.5.12.4 && crc32 12000000 $filesize
	Loading file "/usr/lib/libperl.so.5.12.4" from sata device 0:1 (hda1)
	958032 bytes read
	
	time: 0.414 seconds, 414 ticks
	CRC32 for 12000000 ... 120e9e4f ==> 550deec9
	
With patch:
	MX6QSABRELITE U-Boot > time ext2load sata 0:1 12000000 
/usr/lib/libperl.so.5.12.4 && crc32 12000000 $filesize
	Loading file "/usr/lib/libperl.so.5.12.4" from sata device 0:1 (hda1)
	958032 bytes read

	time: 0.205 seconds, 205 ticks
	CRC32 for 12000000 ... 120e9e4f ==> 550deec9