移植UBOOT1.20到EP9302的CPU

hunter103

在移植UBOOT1.20到EP9302的CPU时出现以下的错误码是原因呢,望请高手们赐教,谢谢.
/home/dev/edb9302/u-boot2/common/exports.c:30: undefined reference to `udelay'
common/libcommon.a(xyzModem.o): In function `CYGACC_COMM_IF_GETC_TIMEOUT':
/home/dev/edb9302/u-boot2/common/xyzModem.c:110: undefined reference to `udelay'
common/libcommon.a(xyzModem.o): In function `xyzModem_get_hdr':
/home/dev/edb9302/u-boot2/common/xyzModem.c:414: undefined reference to `udelay'
common/libcommon.a(xyzModem.o): In function `xyzModem_stream_open':
/home/dev/edb9302/u-boot2/common/xyzModem.c:598: undefined reference to `udelay'
common/libcommon.a(xyzModem.o): In function `xyzModem_stream_terminate':
/home/dev/edb9302/u-boot2/common/xyzModem.c:801: undefined reference to `udelay'
lib_generic/libgeneric.a(vsprintf.o):/home/dev/edb9302/u-boot2/lib_generic/vspri ntf.c:382: more undefined references to `udelay' follow
cpu/arm920t/libarm920t.a(cpu.o): In function `do_reset':
/home/dev/edb9302/u-boot2/cpu/arm920t/cpu.c:135: undefined reference to `reset_c pu'
make: *** [u-boot] 错误 1