[U-Boot] Need help to get u-boot running on the taskit stamp9g20

[Andreas Bießmann]

Dear Markus Hubig,

On 11.07.2012 21:28, Markus Hubig wrote:
> Hello @all,
> 
> as part of my bachelor thesis I'm working with the stamp9g20 / portuxg20
> board from taskit (http://www.taskit.de/produkte/stamp9g20/index.htm). I
> have a patch for a older version (2010.somewhat) of u-boot to get it running
> on this board, but this patch is not working anymore.

well, there where a lot of architectural changes (renames, drop of old
code, ...) in at91 around 2011. This is still work in progress, however
nothing happened since Reinhard gave up. I hope to bring this to an end
this year.

> Now I'm in the process of adapting this patch to the new u-boot. Up to now
> I can compile a u-boot.bin and download it to the board. But after starting up
> the new u-boot I just see this on the serial port
> 
> ---8<------------------------------------------
> U-Boot 2012.04.01-00001-gadcb359-dirty (Jul 11 2012 - 19:24:58)
> 
> CPU: AT91SAM9G20
> Crystal frequency:   18.432 MHz
> CPU clock        :  396.288 MHz
> Master clock     :  132.096 MHz
> DRAM:  64 MiB
> WARNING: Caches not enabled
> NAND:  RomBOOT
> ---8<------------------------------------------

So something went wrong in nand_init()? Two things you should do:
 a) as Wolfgung suggested previously: disable the Watchdog
 b) check for the 'NAND Ready' Pin (use some oscilloscope);
    alternatively just remove the CONFIG_SYS_NAND_READY_PIN R/B should
    be handled by the nand_base driver in another way then.

> and the board is rebooting every some seconds. I'm not able to give it some
> input via the keyboard. I think maybe there are just some small bits missing
> but I'm a bit lost now ... maybe some of you can have a look and can give me
> some advice. ;-)

enable debug for all the drivers/mtd/nand files, put in some more debug
printouts where necessary.

> I include the old patch (portuxg20.patch) and the three patches I made in this
> email. My patches are based on u-boot v2012.04.01.

Please send the patches in line, Wolfgang already sent a pointer
describing ho to achieve this.

Another not related question: What is your Bachelor thesis about? Is
there some space to implement some basic SPL for u-boot on at91?

I'm looking forward to get proper patches for the stamp9g20 to have this
device mainlined. Unfortunately Taskit has not tried to bring their
devices to mainline in the past. Therefore I think this would be your
task if you (or the company you working for) want this device supported
by u-boot mainline code. I don't want to summarize all the advantages,
you just hit one problem of out of tree code ...


Best regards

Andreas Bießmann