[U-Boot] How to boot a newer version of u-boot from a older one?

[Lingfeng Xiong <xionglingfeng@gmail.com>]

hi there,
I bought a Freescale MPC8313E-RDB some days before. The version of 
u-boot on that board is quite old and I wanna run a newer one. I have 
already built the latest git version of u-boot for that board. But I 
found there are several configuration files:
> MPC8313ERDB_33               powerpc     mpc83xx     mpc8313erdb         freescale      -           MPC8313ERDB:SYS_33MHZ
> MPC8313ERDB_66               powerpc     mpc83xx     mpc8313erdb         freescale      -           MPC8313ERDB:SYS_66MHZ
> MPC8313ERDB_NAND_33          powerpc     mpc83xx     mpc8313erdb         freescale      -           MPC8313ERDB:SYS_33MHZ,NAND_U_BOOT
> MPC8313ERDB_NAND_66          powerpc     mpc83xx     mpc8313erdb         freescale      -           MPC8313ERDB:SYS_66MHZ,NAND_U_BOOT

My board is Rev C and all switches are in factory default, could you 
tell me which configuration should I use?

For I have no USBTAP, there are no way for me to flush either NOR Flash 
or NAND Flash, so I am afraid if I install my u-boot to NOR Flash and 
that u-boot cannot run correctly, my board would be unavailable. So I 
wanna boot the latest version of u-boot from the original one. I tried 
these:
=> tftp 0x01000000 u-boot.bin
=> go 0x01000000

But my board reset automatically. Could you tell me how to do with this? 
Thanks.



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