Ok,I will try it by setting "direct" mode.
My linuxbios version don't support CONFIG_COMPRESS option. I have get it from the cwlinux packages.
So,I have checked out the latest cvs version,but I failed to compile it successfully. The file "Liuxbios_c.o" failed to resolve symbol "console_tx_al" and "console_tx_hex8" in the "_start" function when my linker linked these files.Maybe somewhere goes wrong.