Restricting memory area for linux kernel

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Restricting memory area for linux kernel

I am running ltib linux on P1022RDK (P1022 Core) platform. I have 512 MB = 0x20000000 memory. I want my linux kernel to use second half of the board memory (i.e from 256 MB to 512 MB) and want first half of memory to be reserved for some other purpose. For this I am building linux kernel using ltib. For that purpose I am setting following kernel configuration. Please suggest if I am doing it the right way.

CONFIG_LOWMEM_SIZE = 0x10000000 # 256 MB 
CONFIG_PHYSICAL_START = 0x10000000 # Starting from 256MB (second half of memory)

On the Uboot I am loading the kernel as following way

setenv loadaddr 0x11000000 # Kernel base = 0x10000000 + 0x01000000 (offset)
setenv fdtaddr     0x10c00000 # Kernel base = 0x10000000 + 0x00c00000 (offset)
bootm $loadaddr - $fdtaddr 

My kernel Load address is 0x10000000 & kernel entry point is 0x10000000

Doing above configuration / steps my kernel stuck at following on Uboot

## Booting kernel from Legacy Image at 11000000 ...
Image Name: Linux-2.6.32.13
Image Type: PowerPC Linux Kernel Image (gzip compressed)
Data Size: 3352851 Bytes = 3.2 MB
Load Address: 10000000
Entry Point: 10000000
Verifying Checksum ... OK
## Flattened Device Tree blob at 10c00000
Booting using the fdt blob at 0x10c00000
Uncompressing Kernel Image ... OK
================ >> It should uncompress FDT here & continue ==============

Any thoughts ?