Hi
I search for this solution as well 45 minutes ago.
Before this i have ported uclinux on the stratix II developement board.
I took the DE3_150_DDR2_1G_1RANK reference design from the de3 system design cd and try port uclinux on that system. First problem i encounter is that the nios2-terminal hang after this display on the terminal:
nios2-terminal: connected to hardware target using JTAG UART on cable
nios2-terminal: "USB-Blaster [USB 4-1.2]", device 1, instance 0
nios2-terminal: (Use the IDE stop button or Ctrl-C to terminate)
Then i checked the system design again and found that the cpu reset vector and Exception vector are on onchip_mem
Then I disable the onchip_mem and connect the cpu instruction master and data master to the altmemddr which is the high performance DDR2 SDRAM. Then i reconfigure the cpu reset vector and exception vector to altmemddr, regenerate and recompile the design.
After all the configuration, the uClinux amazingly boots up. :D
hope this helps.