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

Thierry Reding thierry.reding at avionic-design.de
Thu Apr 26 14:54:51 CEST 2012


* 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>

Before:

	Tegra2 (Medcom) # time ext2load mmc 0 0x17000000 /boot/uImage
	Loading file "/boot/uImage" from mmc device 0:1 (xxa1)
	5609104 bytes read

	time: 4.638 seconds, 4638 ticks
	Tegra2 (Medcom) # crc32 0x17000000 559690
	CRC32 for 17000000 ... 1755968f ==> 158788be

After:

	Tegra2 (Medcom) # time ext2load mmc 0 0x17000000 /boot/uImage
	Loading file "/boot/uImage" from mmc device 0:1 (xxa1)
	5609104 bytes read

	time: 0.317 seconds, 317 ticks
	Tegra2 (Medcom) # crc32 0x17000000 559690
	CRC32 for 17000000 ... 1755968f ==> 158788be

I can also successfully load the loaded uImage to a prompt, so:

Tested-by: Thierry Reding <thierry.reding at avionic-design.de>
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