GTA01 u-boot and loading apps

Harald Welte laforge at
Fri May 11 08:11:46 CEST 2007

[please follow-up to openmoko-uboot, since this question is not really
 kernel related]

On Fri, May 11, 2007 at 10:17:16AM +1000, Carl van Schaik wrote:
> Hi All,
> I'm starting to work on trying to boot some elf files directly from 
> u-boot on the gta01 platform.

i see.

> Firstly, I havn't been able to get the serial port working. I can 
> connect to u-boot with /dev/ttyACM0 but not via the debug board. What 
> are the baud rates etc, I could not find them on the wiki.

it's 115200 by default.  But you have to switch stderr/stdout/stdin from
'usbtty' to 'serial' in u-boots environment first.   u-boot does not
support multiple console devices simultaneously.

please see the u-boot wiki page on

> Secondly, the u-boot version loaded has been configured with few useful 
> upload configs. Ie there is no ymodem support etc. Only "loads" is 
> provided which is quite a pain to use since i need to convert my apps to 
> srec and possibly remove the NOBITS flags in the elf file first (so my 
> bss is zeroed).

you can use DFU to upload into RAM (0x32000000) whihc is the quickest
possible option, way faster than any serial UART.  If you have the time,
you can also use microSD cards, with fat or ext2/ext3 filesystems on

once again, please see the u-boot wiki page on

> Thirdly, when trying to use loads over the usb tty, u-boot stops 
> responding. I think this is due to sending too much data. Ie if i paste 
> the srec file, line by line, u-boot reads the input fine, but if i 
> "upload" the file, u-boot crashes. I think there is a frame overrun or 
> somthing happening. Should I be using any type of flowcontrol??

the usbtty is currently broken for any bulk data transfers, sorry.

bugfixes to the usbtty code are welcome ;)

> Whats the best way to load elf files to the board? I havn't tried JTAG 
> yet due to my serial problems above.


dfu-util -a 0 -D my_object_file -R

on the host.  After that, use usbtty to 'bootm 0x32000000' or bootelf if
its about elf files.

- Harald Welte <laforge at>         
Software for the world's first truly open Free Software mobile phone

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