Most likely you are using an expression like "x-y" in an instruction, which is not allowed in EABI if both x and y are link-time symbols. You might also be using an expression like "x & 0xffff" or "x >> 1". You'll need to find this instruction; the line number should be given in the full error message text.
See
http://processors.wiki.ti.com/index.php/C6000_EABI_Migration#Relocation_Expressions_Are_Not_Supported