Just how fast is barebox?

[Sascha Hauer]

Hi Geoff,

On Mon, Mar 28, 2011 at 01:25:18PM +1000, Geoff Smith wrote:
> Apologies for the newbie question. I am looking for a fastboot option for
>  the i.MX27
> 
> I want to be capturing video data from a cold start within 300ms (preferably
> 200ms).

The best I could get out of an i.MX27 was about 700ms. The main limiting
factor is how fast you can load an image from the boot medium (Nand
flash in my case). Given that I can read from Nand with 16MB/s a 5MB
image takes about 300ms to load. I think you'll need many dirty tricks
doing this with Linux, like a massively stripped down kernel and perhaps
starting the capture in the kernel (not in the application).

I wouldn't say it's not possible, but it's definitely a hard task.

Sascha


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