Configure 8xx_io in 2.4.21-pre3

The 8xx CPM configuration in 2.4.4 release from DENX has more options than any other release, including 2.4.21-pre3. For example, CONFIG_SMC1_UART is in 2.4.4 (DENX). My board uses SMC1 as UART. I almost needn't to change anything in 2.4.4-denx to make my 8xx CPM working. I'm trying to migrate the kernel to 2.4.21 and the kernel is stuck in my_console_write() and no any message is shown on the console. So I think the problem is in CPM settings. I enabled the following configuations for MPC8xx CPM.
CONFIG_FEC_ENET=y
CONFIG_USE_MDIO=y
CONFIG_FEC_LXT971=y
CONFIG_8xx_COPYBACK=y
CONFIG_UCODE_PATCH=y

How can I set CPM correctly in 2.4.21? Any hints are greatly appreciated.

- Shawn.

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