[meta-xilinx] u-boot SPL from QSPI flash

[Mike Looijmans]

On 02/25/2014 09:13 AM, Alan DuBoff wrote:
>
> On Mon, February 24, 2014 11:10 pm, Mike Looijmans wrote:
>> The SPL removes the need for the "fsbl" and the whole image can now be
>> generated from source code without the annoying manual fifty-mouseclicks step
>> of creating the FSBL.
>
> Mike,
>
> One thing I was going to ask you but forgot...can you get into the u-boot
> prompt on this sd_boot version?

Yes, press and hold ENTER while booting the board. I've configured u-boot for 
a zero boot delay, but it will stop when there's a character in the serial buffer.

The zedboard has a fault in its design, it powers the usb-to-uart chip from 
the board instead of from the USB connector, causing the port to disappear 
when you switch it off, and making it hard to diagnose the bootloader.

What usually works is switch it on, when output appears, hold enter and press 
the reset button on the board.

> Maybe that is why it seems so fast to boot, it bypasses the u-boot sequence it
> seems. I'm ok with that, but the u-boot prompt is needed to flash the images
> to the SPI.

I'm not a big fan of a boot sequence that goes: "I'll just sit here and wait 
for three seconds for you to press a key, and then all of Linux takes less 
than those three seconds to boot."

What I noticed is that the terminal starts showing characters at a further 
stage in the kernel boot process than it used to. That's why I think it's faster.

Mike.


Met vriendelijke groet / kind regards,

Mike Looijmans

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