CONFIG_DRAM_BASE undeclared

HEllo,

in recent kernels CONFIG_DRAM_BASE is undeclared:
./linux/asm/memory.h:175: error: 'CONFIG_DRAM_BASE' undeclared (first
use in this function)

How can I solve this problem? I write a little program wich needs
kernel headers and get this error when I try to compile it.

R.