[U-Boot] Faster boot time

[Simon Schwarz]

On 09/26/2011 04:30 PM, Dat Tran wrote:
> Sorry for my ignorance on this issue. My current system (Overo) does
> this when it boots:
>
>      ROM Code -> X-Load (MLO) -> U-Boot -> Linux Kernel -> Root File System
>
> Does the SPL patch allow me to do this?:
>
>      ROM Code -> U-Boot (MLO) -> Linux Kernel -> Root File System
		    ^U-Boot SPL
>
>
> Also running the latest X-Loader 1.50 and U-Boot 2011.09-rc1, it takes
> about 2 seconds from power on to starting the Linux Kernel. My Kernel
> takes 1 second to load and my file system takes another 1.5 seconds for
> a total of 4.5 seconds from power on to the login prompt on serial. I
> assume the U-Boot-SPL will only speed up the first half of my boot time.
correct.

> If so, how much of a difference do you think I will see with this patch.
I can't say it for your case.

I did this on a devkit8000 loading from NAND. The U-Boot (unoptimized) 
took 3189 ms and Xloader took 1170 ms. By using the SPL this was reduced 
to 850 ms. Another patch I'am working on ATM is utilizing DMA to copy 
the Linux images - this reduces the time spend in SPL to 220 ms.

>
> Thanks.
>

Regards
Simon

> On Mon, Sep 26, 2011 at 7:40 AM, Simon Schwarz
> <simonschwarzcor at googlemail.com <mailto:simonschwarzcor at googlemail.com>>
> wrote:
>
>     Stands for Second Program Loader.
>
>     It loads the U-Boot and runs it - or with this patch a Linux Kernel.
>
>     Regards
>     Simon
>
>
>     On 09/26/2011 02:30 PM, Dat Tran wrote:
>
>         What does SPL stand for again? It looks really interesting.
>
>         Thanks.
>
>         On Mon, Sep 26, 2011 at 3:56 AM, Simon Schwarz
>         <simonschwarzcor at googlemail.__com
>         <mailto:simonschwarzcor at googlemail.com>
>         <mailto:simonschwarzcor at __googlemail.com
>         <mailto:simonschwarzcor at googlemail.com>>>
>
>         wrote:
>
>             On 09/25/2011 10:03 PM, dtran11 wrote:
>
>
>                 I am trying to make uboot boot as fast as possible for
>         my omap3
>                 Overo board.
>                 I add the below to my config header file. Does anyone see
>                 anything I can add
>                 to it to make the build smaller and faster?  Thank you.
>
>
>             [SNIP]
>
>             This may be of interest to you:
>         http://article.gmane.org/____gmane.comp.boot-loaders.u-____boot/108814
>         <http://article.gmane.org/__gmane.comp.boot-loaders.u-__boot/108814>
>         <http://article.gmane.org/__gmane.comp.boot-loaders.u-__boot/108814
>         <http://article.gmane.org/gmane.comp.boot-loaders.u-boot/108814>>
>
>             But will take some hacking to adapt.
>
>             Regards
>             Simon
>
>
>
>