[U-Boot] [PATCH v2] ext2load: increase read speed

[Wolfgang Denk]

Dear Jason Cooper,

In message <1338566090-15008-1-git-send-email-u-boot at lakedaemon.net> you 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.
> 
> The following test results were provided by Eric Nelson:
> 
> 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
> 
> And, the following results were reported by Thierry Reding:
> 
> 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
> 
> End results.
> 
> Signed-off-by: Jason Cooper <u-boot at lakedaemon.net>
> Tested-by: Eric Nelson <eric.nelson at boundarydevices.com>
> Tested-by: Thierry Reding <thierry.reding at avionic-design.de>
> ---
> Changes since v1:
>   - updated commit entry to include test results from Eric Nelson and Thierry
>     Reding
> 
> Based against tag 2012.04.01
> 
>  fs/ext2/ext2fs.c |   26 ++++++++++++++++++++++++--
>  1 files changed, 24 insertions(+), 2 deletions(-)

Applied, thanks.

Best regards,

Wolfgang Denk

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