[U-Boot-Users] uboot source level debugging in TI CCS？

I compiled uboot with debug option -gcoff and downloaded the code into my board successfully through TI OMAP CCS.In the disassembly window, I can see some symbols, such as function name. But I still can't see the soucecode,and don't know how to connect the sourcecode with the executable code. If any one with such experience, please tell me how.Thanks