In u-boot, code or variable addresses cannot be decided when compiling, GOT is used to solve this problem.
STARG_GOT is used to define the start of the table, END_GOT is used to define the end of the table,
GOT_ENTRY is used to write the offset into the table and "GOT" is used for reading the offset from the table.
Please refer to cpu/mpc83xx/u-boot.lds for _FIXUP_TABLE_ defination.