Seyyed Mohammad Sajjadi wrote:
Hi
I am trying to use u-boot on a Xilinx V4FX12 FPGA, in which a ppc405 system is running. The board includes an ST SPI Flash, which I have to use as the only non-volatile memory available (in case important, its Atmark Techno suzaku_v sz410).
I have been able to add the board configuration in u-boot and build an image. But, as ppc405 in xilinx fpga can't but from spi flash, I have to use a first stage bootloader to load u-boot. This seems to be normal in xilinx FPGAs as u-boot in petalinux is loaded to. I thaught, if that's the case, I should be able to load u-boot directly to DDR and test it. But when I do so, u-boot hangs after it reaches relocate_code. I should be missing sth, but don't find it. Could anybody help me?
Hi Seyyed,
I'm not familiar with your hardware (including using the ppc405), but if I understand you correctly, you are trying to manually (e.g. via a debugger) load a test u-boot into DDR and then run it from there.
The typical problem with this approach is that your code does the DDR initialization *while running out of DDR*. While DDR is being initialized, it doesn't work as RAM, which causes your program to crash.
You need to find all of your DDR and processor initialization that causes u-boot initialization to crash, and disable it. There are board configurations that do this with #if constructs, but I don't remember which ones.
For the discouraging discussion, see: http://www.denx.de/wiki/view/DULG/CanUBootBeConfiguredSuchThatItCanBeStartedInRAM
Best regards, gvb