I am porting Linux 2.4.27 on a powerpc MPC8248 based board.
Board Details:
Memory Region Size Address Range Port Size
SDRAM 32MByte 0000_0000 -- 01FF_FFFF 64 bit
InternalMemory 384KByte F000_0000 -- 0F05_FFFF
PCI 1GByte 1000_0000 -- 4FFF_FFFF 32 bit
Flash 32MByte FF00_0000 -- FFFF_FFFF 32 bit

1.SDRAM device size is 16MByte and 32 bit wide .We have used two SDRAMs
for total size of 32MByte and 64bit wide.(P/N:MT48LC4M32B2TG-6)
2.Flash device size is 8MByte and 16 bit wide. We have used two Flashes
for total size of 16MByte and 32bit wide. (P/N: M29W640DB90N6T)

I am using Metrowerks CodeWarrior to debug our kernel code.So code
execution when reaches to :
/* Now turn on the MMU for real! */
lis r3,start_kernel@h
ori r3,r3,start_kernel@l
mtspr SRR0,r3
mtspr SRR1,r4
--> RFI
this part at instruction "RFI" execution reaches to Instruction access
exception and never come back to start_kernel funtion..
Beside these things when i simply look into logbuffer It shows:0
OOPs:Kernel Access of Bad area sig<11>:
and sometime it shows pagefault:

Please help me . I am really struggling .If anyone needs more info
,please ask.