Hi All, Am able to get some messages on serial port but it is hanging after DRAM initialization i.e. during relocate_code function, below is the debug messages on serial port. I tried configuring SDRAM (DDR2) for 256 and 128 MB, but still the problem is same. I am facing one typical problem in u-boot i.e. whenever i power on the board I will get below debug messages on serial port after 5 to 8 seconds and hangs at stack pointer. U-Boot 2010.03 (May 14 2010 - 16:41:46) Linux Advanced AVN Platform CPU: Au1350, id: 0x80, rev: 0x01 DRAM: 256 MB Address value =90000000Top of RAM usable for U-Boot at: 90000000 Reserving 161k for U-Boot at: 8ffd4000 Reserving 192k for malloc() at: 8ffa4000 Reserving 36 Bytes for Board Info at: 8ffa3fdc Reserving 36 Bytes for Global Data at: 8ffa3fb8 Reserving 128k for boot params() at: 8ff83fb8 Stack Pointer at: 8ff83f98 U-Boot 2010.03 (May 14 2010 - 16:49:00) Linux Advanced AVN Platform CPU: Au1350, id: 0x80, rev: 0x01 DRAM: 128 MB Address value =88000000Top of RAM usable for U-Boot at: 88000000 Reserving 161k for U-Boot at: 87fd4000 Reserving 192k for malloc() at: 87fa4000 Reserving 36 Bytes for Board Info at: 87fa3fdc Reserving 36 Bytes for Global Data at: 87fa3fb8 Reserving 128k for boot params() at: 87f83fb8 Stack Pointer at: 87f83f98 U-Boot 2010.03 (May 14 2010 - 16:53:58) Linux Advanced AVN Platform CPU: Au1350, id: 0x80, rev: 0x01 DRAM: 256 MB Address value =90000000Top of RAM usable for U-Boot at: 90000000 Reserving 161k for U-Boot at: 8ffd4000 Reserving 192k for malloc() at: 8ffa4000 Reserving 36 Bytes for Board Info at: 8ffa3fdc Reserving 36 Bytes for Global Data at: 8ffa3fb8 Reserving 128k for boot params() at: 8ff83fb8 Stack Pointer at: 8ff83f98 Can you please share me your board config file and lowlevel_init.S file which you have ported u-boot for Au1550. I need it for the reference. I am doing DDR2 initialization in u-boot as per YAMON source code that will create any problem? please help me out to resolve the above issues. Thanks in Advance Regards, Gurumurthy Gowdar KPIT Cummins Infosystems Pvt Ltd