PPC Linux start address on XUPV2P board

Hi,

  I am running the Linux 2.6.24 kernel from the git.xilinx.com source
  tree.
  
  I am just wondering what is the start address that is used for
  the Linux kernel in RAM/SDRAM on the Xilinx XUPV2P board and
  where is this defined in the Linux kernel sources?
  
  Also does the PPC Linux kernel support true 64-bit write/read access
  to peripherals on the XUPV2P board or similar boards?

  Any info. appreciated,
  Regards,
  Alan.