u-boot migrate promble

Dear Sir/Miss,
When I migrate u-boot-1.1.3 to LPC2294, the board and terminal can not display any information of u-boot-1.1.3, whether or not my serial port have problem? Because I study u-boot just now, I do not know how to study it and solve the problems that when I migrate it to LPC2294 board, please you help me, thank you very much!
I have some questions
1.
#define FLASH_SST200A 0x0040 /* SST 39xF200A ID ( 2M = 128K x 16 ) */ #define FLASH_SST400A 0x0042 /* SST 39xF400A ID ( 4M = 256K x 16 ) */ #define FLASH_SST800A 0x0044 /* SST 39xF800A ID ( 8M = 512K x 16 ) */ #define FLASH_SST160A 0x0046 /* SST 39xF160A ID ( 16M = 1M x 16 ) */ #define FLASH_SST320 0x0048 /* SST 39xF160A ID ( 16M = 1M x 16 ) */ #define FLASH_SST640 0x004A /* SST 39xF160A ID ( 16M = 1M x 16 ) */ #define FLASH_SST040 0x000E /* SST 39xF040 ID (512KB = 4Mbit x 8 ) */ what these define comes? is in the produce datasheet? I couldn't find in the datasheet ,I just find the
device id and Manfacturer's ID.
and I use the nor flash sst339vf1601.
2.
which file's are define the CPU frequency set ?
3.
how can I debug the u-boot? I can't display any information of through the serial port ?
4.
is the any doc about the source cold struct of the u-boot?

Thank you very much!!!
Yours sincerely,
Yong xu