I'm encountering a strange problem trying to run recent versions of u-boot from RAM on my DockStar.

I have version 2011.03 in NAND flash, and it boots OK and launches Linux OK. But if I use it to load u-boot.bin into RAM (at TEXT_BASE = 0x600000) and type "go 600000", it hangs soon after the relocation step. I've checked using crc32 that the image is correct in RAM, and I've used both tftpboot and fatload, with identical results.

But here's the strange part: if I use openocd to load the same image to the same location using JTAG, and do "resume 0x600000", it works correctly.

I'm not sure what the difference could be. Does anyone have any ideas? It's a lot more convenient to use TFTP to test out new images than JTAG, so I'd like to get this working.