Hi Jyotshna,
Is your u-boot code doing any register initializations?
I am modifying the MPC8260ads configurations to match my board but I don't see any messages being printed on the serial port. I am using Codewarrior USB TAP debugger to debug the u-boot code with an initialization file as follows:
setMMRBaseAddr 0x00000000 writemmr SCCR 0x0000 writemmr SYPCR 0xffffffc3 writemmr RMR 0x0001 # Memory periodic timer prescaler writemmr MPTPR 0x3200 # Internal memory map register writemmr IMMR 0x04700000
With the above initialization file when I define CONFIG_IMMR to 0xF0000000 in u-boot it just doesn't go further and so I modified it to be same as the initilization file ( 0x0470000) and now I am stepping little further into the code but I am getting stuck at a point in cpu_init_f in start.S.
If the debugger has done the processor initialization part, trying to do the same in u-boot might cause problems. I'll suggest you to comment out the initialization from u-boot and try. Most probably, setting OR and BR registers in cpu_init_f might be the issue.
Regards, Jayakrishnan