Booting images with uboot get stuck after execution of rtems

[Jan Sommer]

Hi,

I currently try to load my rtems binaries through uboot and tftp for the raspberry pi, because I am getting tired of the sd-card switching.
I used this tutorial to build uboot from Stephen Warren's branch: http://elinux.org/RPi_U-Boot
uboot boots fine and the tftp transfer works too.
However if I try to boot the transferred image it get stuck after a short time (see below).
If I copy the same image file onto the sd-card and run it directly (without uboot) it executes normally.
I used the commands from https://rtime.felk.cvut.cz/hw/index.php/Raspberry_Pi#RTEMS_Boot_with_use_of_U-boot to create the image file:

arm-rtems4.11-objcopy -R -S --strip-debug -O binary ticker.exe ticker.bin || exit 1
cat ticker.bin | gzip -9 >ticker.gz
mkimage -A arm -O rtems -T kernel -a 0x00008000 -e 0x00008000 -n "RTEMS" -d ticker.gz ticker.img

Do I need to do something else before booting, e.g. set some environment variable?

Best regards,

    Jan

U-Boot> dhcp ${kernel_addr_r} ticker.img
Filename 'ticker.img'.

Load address: 0x1000000

Loading: *\0x08#####

\0x09 1.5 MiB/s

done

Bytes transferred = 69269 (10e95 hex)

U-Boot> bootm ${kernel_addr_r}

## Booting kernel from Legacy Image at 01000000 ...

   Image Name:   RTEMS

   Image Type:   ARM RTEMS Kernel Image (gzip compressed)

   Data Size:    69205 Bytes = 67.6 KiB

   Load Address: 00008000

   Entry Point:  00008000

   Verifying Checksum ... OK

   Uncompressing Kernel Image ... OK

## Transferring control to RTEMS (at address 00008000) ...

*** CLOCK TICK TEST ***
TA1  - rtems_clock_get_tod - 09:00:00   12/31/1988
TA2  - rtems_clock_get_tod - 09:00:00   12/31/    <--- Execution gets stuck