[meta-xilinx] load bitstream through u-boot

[gmane at reliableembeddedsystems.com]

Hi,

I built the meta-xilinx jethro branch for the zedbaord and was able to 
boot Linux.

Now I would like to load a bitstream through u-boot.

Is this supposed to work?

fatload mmc 0 0x3000000 system_wrapper.bit
fpga load 0 0x3000000 ${filesize}

but I get:

zynq_validate_bitstream: Bitstream is not validated yet (diff 70).

Can someone tell me what this means?

Does my hardware person need to produce the bistream in some different 
way?
If so how?

Is it me using it the wrong way?

Regards,

Robert