Linux/AM3352: using newest sdk in my custom board cannot start and print no log message!

Part Number:AM3352

Tool/software: Linux

hi，all

    my custom board is just the same as the beableoneblack but with no eeprom.  I use the newest sdk PROCESSOR-SDK-LINUX-AM335X 04_01_00_06，and I use the sdcard boot the beableoneblack board successfully, but when I use the same sdcard to boot my custom board ,there is no log and I don't know what is wrong with it . in the past ,I used porting the sdk6.0 to my custom board , I used the prebuild sdk, It will print log, but now ,there is no log? how can I fix this problem??